January 2014 An Evidence-Based Approach Volume 16, Number 1 To Emergency Department Authors John R. Marshall, MD Department of , Lincoln Medical and Mental Management Of Health Center, Bronx, NY Jordana Haber, MD Department of Emergency Medicine, Maimonides Medical Center, Acute Urinary Retention Brooklyn, NY Elaine B. Josephson, MD, FACEP Assistant Professor of Emergency Medicine in Clinical Medicine, Abstract Weill Cornell Medical College of Cornell University, New York, NY; Emergency Medicine Residency Program Director, Lincoln Medical and Mental Health Center, Bronx, NY Approximately 10% of men in their 70s and 33% of men in their 80s report at least 1 episode of acute urinary retention, and this urologi- Peer Reviewers cal emergency presents unique assessment and treatment challenges William J. Brady, MD Professor of Emergency Medicine and Medicine, Chair, Medical in the emergency department setting. Patients presenting with Emergency Response Committee, Medical Director, Emergency acute urinary retention are often in severe pain and require urgent Management, University of Virginia Medical Center, Charlottesville, VA diagnosis and prompt treatment. The differential diagnosis of acute Joseph D. Toscano, MD urinary retention is vast, with some causes leading to permanent Chairman, Department of Emergency Medicine, San Ramon Regional Medical Center, San Ramon, CA impairment if not dealt with in a timely manner. Quick recogni-

tion of the cause and timely bladder decompression are of utmost CME Objectives importance in preventing morbidity and relieving pain. This review Upon completion of this article, you should be able to: analyzes the etiology, key historical and physical findings, differen- 1. Describe the pathophysiology and complications of AUR. 2. Distinguish key physical examination findings, including red flags, tial diagnosis, and diagnostic studies for acute urinary retention in that may help identify patients with AUR. both men and women. Treatment algorithms for men and women, 3. Interpret the treatment algorithms for AUR in men and women. current controversies regarding urinary usage, and recom- Prior to beginning this activity, see “Physician CME Information” on the mendations on criteria for disposition are also presented. back page.

Editor-In-Chief of Medicine at Mount Sinai, New Attending Physician, Massachusetts Icahn School of Medicine at Mount Research Editor Andy Jagoda, MD, FACEP York, NY General Hospital, Boston, MA Sinai, New York, NY Michael Guthrie, MD Professor and Chair, Department of Michael A. Gibbs, MD, FACEP Charles V. Pollack, Jr., MA, MD, Scott Silvers, MD, FACEP Emergency Medicine Residency, Emergency Medicine, Icahn School Professor and Chair, Department FACEP Chair, Department of Emergency Icahn School of Medicine at Mount of Medicine at Mount Sinai, Medical of Emergency Medicine, Carolinas Professor and Chair, Department of Medicine, Mayo Clinic, Jacksonville, FL Sinai, New York, NY Director, Mount Sinai Hospital, New Medical Center, University of North Emergency Medicine, Pennsylvania York, NY Carolina School of Medicine, Chapel Hospital, Perelman School of Corey M. Slovis, MD, FACP, FACEP International Editors Professor and Chair, Department Hill, NC Medicine, University of Pennsylvania, Peter Cameron, MD Associate Editor-In-Chief Philadelphia, PA of Emergency Medicine, Vanderbilt Steven A. Godwin, MD, FACEP University Medical Center; Medical Academic Director, The Alfred Kaushal Shah, MD, FACEP Professor and Chair, Department Michael S. Radeos, MD, MPH Emergency and Trauma Centre, Associate Professor, Department of Director, Nashville Fire Department and of Emergency Medicine, Assistant Assistant Professor of Emergency International Airport, Nashville, TN Monash University, Melbourne, Emergency Medicine, Icahn School Dean, Simulation Education, Medicine, Weill Medical College Australia of Medicine at Mount Sinai, New University of Florida COM- of Cornell University, New York; Stephen H. Thomas, MD, MPH York, NY George Kaiser Family Foundation Giorgio Carbone, MD Jacksonville, Jacksonville, FL Research Director, Department of Chief, Department of Emergency Emergency Medicine, New York Professor & Chair, Department of Gregory L. Henry, MD, FACEP Medicine Ospedale Gradenigo, Editorial Board Hospital Queens, Flushing, NY Emergency Medicine, University of William J. Brady, MD Clinical Professor, Department of Oklahoma School of Community Torino, Italy Professor of Emergency Medicine Emergency Medicine, University Ali S. Raja, MD, MBA, MPH Medicine, Tulsa, OK Amin Antoine Kazzi, MD, FAAEM and Medicine, Chair, Medical of Michigan Medical School; CEO, Director of Network Operations and Ron M. Walls, MD Associate Professor and Vice Chair, Emergency Response Committee, Medical Practice Risk Assessment, Business Development, Department Professor and Chair, Department of Department of Emergency Medicine, Medical Director, Emergency Inc., Ann Arbor, MI of Emergency Medicine, Brigham University of California, Irvine; and Women’s Hospital; Assistant Emergency Medicine, Brigham and Management, University of Virginia John M. Howell, MD, FACEP American University, Beirut, Lebanon Professor, Harvard Medical School, Women’s Hospital, Harvard Medical Medical Center, Charlottesville, VA Clinical Professor of Emergency Boston, MA School, Boston, MA Hugo Peralta, MD Peter DeBlieux, MD Medicine, George Washington Scott D. Weingart, MD, FCCM Chair of Emergency Services, Professor of Clinical Medicine, University, Washington, DC; Director Robert L. Rogers, MD, FACEP, Associate Professor of Emergency Hospital Italiano, Buenos Aires, Interim Public Hospital Director of Academic Affairs, Best Practices, FAAEM, FACP Medicine, Director, Division of Argentina of Emergency Medicine Services, Inc, Inova Fairfax Hospital, Falls Assistant Professor of Emergency ED Critical Care, Icahn School of Dhanadol Rojanasarntikul, MD Louisiana State University Health Church, VA Medicine, The University of Maryland School of Medicine, Medicine at Mount Sinai, New Attending Physician, Emergency Science Center, New Orleans, LA Shkelzen Hoxhaj, MD, MPH, MBA Baltimore, MD York, NY Medicine, King Chulalongkorn Francis M. Fesmire, MD, FACEP Chief of Emergency Medicine, Baylor Memorial Hospital, Thai Red Cross, Professor and Director of Clinical College of Medicine, Houston, TX Alfred Sacchetti, MD, FACEP Senior Research Editors Thailand; Faculty of Medicine, Assistant Clinical Professor, Research, Department of Emergency Eric Legome, MD Chulalongkorn University, Thailand Medicine, UT College of Medicine, Department of Emergency Medicine, James Damilini, PharmD, BCPS Chief of Emergency Medicine, Clinical Pharmacist, Emergency Suzanne Peeters, MD Chattanooga; Director of Thomas Jefferson University, King’s County Hospital; Professor of Room, St. Joseph’s Hospital and Emergency Medicine Residency Center, Erlanger Medical Center, Philadelphia, PA Clinical Emergency Medicine, SUNY Medical Center, Phoenix, AZ Director, Haga Hospital, The Hague, Chattanooga, TN Downstate College of Medicine, Robert Schiller, MD The Netherlands Brooklyn, NY Chair, Department of Family Joseph D. Toscano, MD Nicholas Genes, MD, PhD Medicine, Beth Israel Medical Chairman, Department of Emergency Assistant Professor, Department of Keith A. Marill, MD Center; Senior Faculty, Family Medicine, San Ramon Regional Assistant Professor, Harvard Medical Emergency Medicine, Icahn School Medicine and Community Health, Medical Center, San Ramon, CA School; Emergency Department Case Presentations often leads to inconsistent and suboptimal recogni- tion and management of female patients. It’s a typically busy morning in your community ED. This issue of Emergency Medicine Practice pres- The average wait time to be seen is 1 hour when a ents a systematic review of the latest evidence 66-year-old man with and high cholesterol regarding the pathophysiology, diagnosis, and states that he has been unable to urinate for a few days treatment of AUR, with a focus on controversies and and now has suprapubic pain and . He denies advances in care. and chills. He also notes that, in the past, he was diagnosed with benign prostatic hypertrophy and has re- Critical Appraisal Of The Literature quired Foley placement. It seems simple enough, and you anticipate he will be out as soon as the Foley and leg bag An initial search utilizing the PubMed® database are in place. You wonder if a rectal exam is needed and from 1960 to 2013 was performed using the search how fast his bladder can be emptied... term management of acute urinary retention, with It’s 2:00 PM and you are about to finally grab some a total of 385 results produced. Full texts for 122 lunch, but in comes a 72-year-old man with a history of articles were reviewed, of which 69 are cited in this large cell lymphoma for the past 15 years. He complains of review. Two Federal Aviation Administration (FAA) dribbling urinary frequency, which has worsened over 1 guideline appendices studying the treatment of day after being prescribed an antibiotic by his doctor for a AUR in airplane flight as well as a website on flight UTI. The nurse asks him to walk to another stretcher, and safety were also reviewed. In addition, the Cochrane as he gets up, he stumbles and catches himself with his Database of Systematic Reviews was searched with hands. As you prepare to do the bladder ultrasound, you regard to the treatment of AUR. In 1994, A BPH wonder why he stumbled... guidelines panel published recommendations for It’s finally 6:30PM , with just 30 minutes until relief the diagnosis and treatment of BPH, and in 2004 the arrives. You are spending the last half hour of your shift American Urological Association published more tying up the loose ends with your current patients when up-to-date guidelines in light of new evidence-based 6 a 46-year-old febrile woman with a history of active intra- clinical trials. A thorough literature review revealed venous drug abuse and HIV comes in. She is in excruciat- that the major focus of AUR research involves the ing discomfort and tells you that she has not urinated in 2 treatment of BPH. With the exception of general days. You wonder if that is possible, and why... review articles and case reports, there is little pub- lished original research that focuses specifically on Introduction the treatment of AUR in women, and this remains an area in need of further research. Acute urinary retention (AUR) is commonly seen in the emergency department (ED), most often in older Epidemiology 1 men with benign prostatic hypertrophy (BPH). AUR is defined as the inability to pass urine volun- A cohort study of 2115 men aged 40 to 79 years tarily, and the distended bladder causes extreme reported the incidence of AUR to be between 2.2 and discomfort, often requiring immediate attention and 6.8 per 1000 men per year (95% confidence inter- 7,8 intervention. There are many concerning and poten- val [CI], 5.2-8.9), with a 10-year cumulative risk tially dangerous causes of AUR, and the onus is on of 4% to 73% (meaning that the risk is cumulative 8 the emergency clinician to consider these etiologies and increases with advancing age). A man’s risk and eliminate them before assuming that it is caused of urinary retention is directly correlated to his age, by a benign process. Urgent treatment in the ED is urinary symptom severity, volume, and 8 of utmost importance for acute pain management, urinary flow rate. It is estimated that 1 in 10 men to prevent insult to the kidneys, and to address the aged in their 70s will experience an episode of AUR, underlying causes of AUR (such as cauda equina increasing to 1 in 3 men aged in their 80s. There is syndrome, , tumors, etc). a 20% recurrence rate within 6 months after an epi- In women, the most common causes of AUR sode of urinary retention in patients with AUR due are bladder masses, gynecologic , and pelvic to BPH and 4% recurrence in those with AUR due to 2,3 9 prolapse. Unlike the abundance of clinical studies other causes. Female AUR is relatively uncommon, on older men with BPH-related AUR, women have with much variation regarding incidence and little typically been excluded from AUR studies, and little published data addressing occurrence rates. AUR published data are found in the literature addressing in women is estimated to account for only 3 out of 2 women with this condition. An article by Preminger 100,000 cases of AUR each year, with an incidence 10 et al in 1983 emphasized the importance of assessing estimated at around 0.07 per 1000 females. 4 for organic illness for women with AUR. The rela- In certain populations, AUR may be an indicator tively low incidence of women with AUR in the ED of potential morbidity and mortality. One systematic combined with the paucity of published evidence review of 176,046 men aged > 45 years with a first

Emergency Medicine Practice © 2014 2 www.ebmedicine.net • January 2014 episode of AUR reported, in the subset of hospital- The cortical control of voiding involves the ized men aged > 85 years, a 1-year predicted mortal- connection between the frontal cortex and the septal- ity rate of 33% after an episode of spontaneous AUR; preoptic region of the hypothalamus as well as the those with AUR from precipitated causes had a connections between the paracentral lobule and the 7 1-year predicted mortality rate of 45%. Among men brainstem. The process involves inhibition of so- with AUR who are admitted to the hospital, those matic neural efferent activity to the striated sphinc- with comorbid disease are found to have a higher ter, inhibition of spinal sympathetic reflexes (outlet mortality rate at both 90 days and at 1 year than relaxation, both internal and external sphincters), 7 those admitted with AUR without comorbid illness. and facilitation of efferent parasympathetic pelvic Although the incidence of spontaneous AUR is nerves for detrusor muscle contraction. well studied, there are little data on the incidence Any factors that interfere with the neurologic of drug-induced AUR. Data from observational control of the voiding process can result in void- studies suggest that up to 10% of episodes may be ing dysfunction. Urinary retention is defined as 11 attributable to the concurrent use of . the inability to void voluntarily in spite of a full, In a prospective cohort of 41,276 male health profes- distended bladder. As bladder outlet obstruction sionals 45 to 83 years of age, Meigs et al studied risk (by any means) progressively increases, the urine factors and found that the use of calcium channel stream decreases in size and strength despite force- antagonists and drugs doubled and ful and prolonged detrusor contraction. Over long 12 tripled, respectively, the risk of AUR. periods of time, this mechanism results in decon- In cases of AUR secondary to spinal cord com- ditioning, which leads to dimished detrusor muscle pression, only rarely was AUR a presenting sign or contractility and a larger amount of residual urine 14 chief complaint, but a review study of 133 patients volume. For an illustration of the neuronal control found that, once the diagnosis of of micturition, see Figure 1 (page 4). was made, up to 39% to 43% of patients were de- 13 scribed as having bladder or bowel dysfunction. Etiology

Pathophysiology The etiology of AUR is divided into 5 categories: (1) pharmacologic, (2) neurologic, (3) infectious and The voiding process (micturition) involves the inte- inflammatory, (4) obstructive, and (5) other. BPH, gration of high cortical sympathetic, parasympathet- which is in the obstructive category and is a primary ic, and somatic functions. Normal voiding requires cause of AUR, is referred to as "spontaneous" AUR. a coordinated contraction of bladder smooth muscle Other causes of AUR (eg, infection, side (detrusor muscle) with the simultaneous lowering effects, surgery, or trauma) are referred to as "pre- 15 of resistance at the level of sphincter smooth muscle cipitated" causes of AUR. and striated muscle and the absence of anatomic obstruction. Urinary retention thus results from Pharmacologic Causes an increased resistance to flow via mechanical or Medications may cause prolonged bladder immotil- dynamic means, diminished neurogenic control of ity or increased sphincter tone, with resultant AUR. detrusor muscle contractility, and the subsequent These medications include that 14 decompensating of voiding function. inhibit detrusor muscle activity, sympathomimetic Sympathetic innervation originating from the drugs that increase alpha-adrenergic tone in the T10 to L2 spinal cord is responsible for the control prostate, and nonsteroidal anti-inflammatory drugs of lower urinary tract and urine storage function. (NSAIDs) that may inhibit prostaglandin-mediated Somatic innervation via the pudendal nerve (S2, S3, detrusor muscle contraction. Patients on chronic opi- and S4) maintains sensory input and pelvic muscle oid therapy are also at an increased risk for devel- tone. As the sensory impulse of bladder distention opment of AUR as a result of experiencing reduced 11 is transmitted to cortical centers, these areas of the bladder-fullness sensation. For a list of medica- brain smoothly coordinate voluntary . tions associated with AUR, see Table 1, page 5. Holding urine requires both relaxation of the detru- sor muscle through parasympathetic inhibition and Neurologic Causes beta-adrenergic stimulation and contraction of the Neuropathic etiologies (eg, diabetic cystopathy) bladder neck and internal sphincter through alpha- are also causes of AUR. Up to 45% of patients with adrenergic stimulation. Conversely, urination oc- mellitus and 75% to 100% of patients with curs via contraction of the bladder detrusor muscle diabetic will experience uri- 16-18 via cholinergic muscarinic receptors and relaxation nary retention at some point in their lives. Upper of both the internal sphincter of the bladder neck motor neuron lesions that cause a deficit above the and the urethral sphincter through alpha-adrener- micturition center in the sacral cord are associated gic inhibition. with multiple sclerosis, trauma, Parkinson disease,

January 2014 • www.ebmedicine.net 3 Emergency Medicine Practice © 2014 21,22 stroke, and . Lower motor neuron lesions AUR. One prospective study followed a cohort causing bladder flaccidity with AUR include spinal of 310 men over a 2-year period and found that AUR cord tumors, epidural abscesses, and trauma. One was caused by BPH in 53% of patients, while other 23 review examined 3 cases where cord compression obstructive causes accounted for another 23%. This as the cause of AUR was missed by the ED physi- is important to keep in mind, as precipitated and cian in patients with a present history of enlarged spontaneous causes of AUR differ greatly in their 19 prostate. treatments and outcomes.

Infectious Or Inflammatory Causes Other Causes Infectious or inflammatory causes of AUR include In patients during the postpartum period, the 24 urethritis from a (UTI), incidence of AUR was found to be 1.7% to 17.9%. , severe vulvovaginitis, or viral causes (eg, In a prospective study of 1000 women, it was 20 involving the sacral nerves). found that women who received epidural anesthe- sia during labor were significantly more likely to 25 Obstructive Causes experience AUR than those who did not. In cases Obstructive causes of AUR are divided into intrinsic where trauma is a suspected cause of AUR, etiolo- causes (eg, prostatic enlargement, bladder stones), gies to keep in mind include acute trauma to the or extrinsic causes (eg, uterine or gastrointestinal , penis, or bladder; spinal cord injury; and masses). Obstructive causes in women often involve bladder/urethral rupture with associated pelvic pelvic organ prolapse (eg, or rectocele) or fracture. 16,17 malignant pelvic masses. Compared to chronic urinary retention, AUR Although there are many possible causes of is usually painful, while more-slowly obstructing AUR, BPH remains the most common cause of pathological processes (ie, tumors) tend to be pain-

Figure 1. Pathophysiology Of Micturition

Bladder wall stretch HigherHigher brainbrain centerscenters

Allow or inhibit micturition as appropriate

Afferent impulses from stretch receptors Pontine micturition center Pontine storage centers

Promotes by acting on Inhibits by Simple spinal reflex all 3 spinal efferents acting on all 3 spinal efferents ➞ ➞

➞ Parasympathetic activity Sympathetic activity Somatic motor activity ➞ Parasympathetic activity

➞ Sympathetic activity

➞ Somatic motor activity Detrusor contracts; internal External urethral urethral sphincter opens sphincter opens

Key: Gray boxes: bladder White boxes: spinal cord Black boxes: brain Inhibits Solid lines/arrows: nerves promoting urination Micturition Dashed lines: nerves inhibiting urination

MARIEB, ELAINE N.; HOEHN, KATJA, HUMAN ANATOMY & PHYSIOLOGY, 8th, © 2010. Printed and Electronically reproduced by permission of Pearson Education, Inc., Upper Saddle River, New Jersey.

Emergency Medicine Practice © 2014 4 www.ebmedicine.net • January 2014 free. Often, already established obstruction comes to due to (or confused with) vaginal or penile carci- light when a superimposed acute obstruction occurs, noma, severe infection, trauma, testicular torsion, preventing effective urination (acute-on-chronic or organ prolapse. Because of the large differential urinary retention). For many patients presenting to diagnosis in AUR, a comprehensive history and the ED with a first-time case of AUR, AUR is the first physical examination are indicated when evaluating symptom of underlying prostate hyperplasia. The these patients. emergency clinician must distinguish more benign processes from an etiology that is emergent and Prehospital Care requires urgent operative treatment (eg, AUR that is caused by ). See Table 2 On The Ground for a list of causes of AUR and Table 3 for gender- Care for the patient with AUR in the prehospital set- specific causes of AUR (page 6). ting is centered on providing comfort to the patient during transport to the ED for further evaluation. Differential Diagnosis Serious cases may involve severe pain, infection, or autonomic hyperreflexia. Depending on local AUR can present with very vague complaints in- protocols and the patient’s presentation, prehospital volving multiple organ systems, which can lead to management may include alleviating pain, correct- very broad differential diagnoses. Common com- ing hypovolemia, and relieving urinary retention by 26 plaints may include or distension means of placement. that may be mistaken for conditions such as small- bowel obstruction, organ prolapse, carcinoma, uri- In The Sky nary tract infection, or prostatitis. A presentation of With an increase in the number of elderly individu- back pain may be confused with renal pathology or als (ie, patients aged ≥ 65 years) flying on com- spinal tumors. Commonly seen urinary complaints mercial aircraft, there will likely be an increasing (eg, frequency, dribbling) may also be manifestations incidence of AUR in flight. In a recent European of toxin exposure or from neurological causes such review of over 1000 cases of surgical and medical as diabetes, cerebrovascular accident, or spinal cord emergencies in flight, AUR was not listed as a more compression. AUR presenting as genital pain may be

Table 1. Medications Associated With Acute Urinary Retention16

Classification Generic Names (Brand Names) Antiarrhythmics (Norpace®, Rhythmodan®); procainamide (Pronestyl®, Procan®, Procanbid®); quinidine Anticholinergics (Atreza®, Sal-Tropine®, AtroPen®); belladonna alkaloids; dicyclomine (Bentyl®, Byclomine®, Dibent®); flavoxate (Urispas®); glycopyrrolate (Robinul®, Cuvposa®); hyoscyamine (Symax®, HyoMax®, Levsin®, et al); (Ditro- pan®, Gelnique®, Oxytrol®); ; Antidepressants Amitryptyline (Elavil®, Amitril®); (Asendin®, Defanyl®, Demolox®); (Sinequan®, Silenor®); (Tofranil®); maprotiline (Ludiomil®); (Sensoval®, Aventyl®, Pamelor®, et al) Brompheniramine (Ala-Hist®, Dimetane®, Brovex®, et al); chlorpheniramine (Chlor-Trimeton®, Antagonate®, Phenetron®, et al); cyproheptadine (Periactin®); (Unisom®, Nytol®, Benadryl®, et al); hydroxyzine (Atarax®, Hy- pam®, Vistaril®, et al) Antihypertensives Hydralazine (Apresoline®, Dralzine®, plus multiple combination products); nifedipine (Adalat®, Nifedical®, Procardia®) Antiparkinsonians Amantadine (Symmetrel®); benztropine (Cogentin®); bromocriptine (Cycloset®, Parlodel®); levodopa (Sinemet®, Par- copa®, Larodopa®); trihexyphenidyl (Artane®, Tremin®) Antipsychotics Chlorpromazine (Promapar®, Thorazine®); fluphenazine (Permitil®, Prolixin®); haloperidol (Haldol®); prochlorperazine (Compazine®); thioridazine (Mellaril®); thiothixene (Navane®) Hormonal agents Estrogen; progesterone; Muscle relaxants Baclofen (Kemstro®, Lioresal®); (Amrix®, Flexeril®); (Valium®) Sympathomimetics (alpha) Ephedrine; phenylephrine (Lusonal®; plus multiple combination products, eg, Dimetapp®, Neo-Synephrine®, Sudafed PE®, et al); phenylpropanolamine; (Afrinol®, Silfedrine®, Sudafed®, et al; plus multiple combination products) Sympathomimetics (beta) Isoproterenol/isoprenaline (Isuprel®); metaproterenol (Alupent®); terbutaline (Brethine®, Bricanyl®) Miscellaneous ; carbamazepine (Carbatrol®, Epitol®,Tegretol®, et al); dopamine (Intropin®); mercurial diuretics; nonste- roidal anti-inflammatory drugs, analgesics; vincristine (Oncovin®, Vincasar®, Vincrex®, et al)

Drug brand names examples are from the Medline Plus® website, www.MedlinePlus.gov. Adapted from Emergency Medicine Clinics of North America, Volume 19, Issue 3. Liesl A. Curtis, Teresa Sullivan Dolan, R. Duane Cespedes, Acute Urinary Retention and . Pages 591-620, Copyright 2001, with permission from Elsevier.

January 2014 • www.ebmedicine.net 5 Emergency Medicine Practice © 2014 27 common concern. However, the true incidence pain often radiates to the scrotum or labia. A full list of AUR in flight may be underreported. Current of patient medications should be obtained including guidelines provided by the aviation Medical Assis- new medications, over-the-counter medications, and tance Act require that all United States commercial herbal remedies. When inquiring about a possible aircraft be equipped with an automatic external toxicologic cause of AUR, regardless of the patient's defibrillator and an emergency medical kit, but a gender, the emergency clinician should inquire about 28-30 Foley catheter is not specified. Many interna- any illicit drug usage, misuse of medications, chemi- tional carriers do include a Foley catheter in their cal exposure, history of psychiatric illness, and suicid- standard equipment. In the event of suspected AUR al intent or ideation. In women and men, a history of in flight, the patient’s stability would guide manage- , bone pain, and other constitutional signs ment. Interestingly, urinary retention is a recognized and symptoms may suggest an underlying . medical problem observed in both short-duration In men, a history of urinary frequency, urgency, and prolonged space flight and research has looked hesitancy, , difficulty initiating a urinary 31 at a percutaneous solution. stream, decreased force of stream, incomplete void- ing, or terminal dribbling may indicate an enlarged Emergency Department Evaluation or inflamed prostate as the cause of the AUR. Women with obstruction often complain of History pelvic pain and abdominal pressure. A history of The history for a patient with AUR focuses on de- , urgency, discharge, chills, fever, low back termining which of the etiologies in the differential pain, and genital itching should be sought in order diagnosis may be involved. The location, movement, to assess for possible infectious causes such as UTI and radiation of the pain help to determine whether and vulvovaginitis. the involved process is proximal or distal to the blad- The elderly patient, the nonverbal patient, or the der. If the pain is proximal to the bladder, there is patient with dementia may not be able to divulge often flank pain; with pain distal to the bladder, the a history and may present with only agitation and restlessness. In these patients, family and caregivers may provide the critical history needed to direct the Table 2. Common Causes Of Acute Urinary evaluation. Other questions to ask include a history Retention1 of known neurological disorders and history of prior episodes of urinary retention. Regardless of gender, neurologic issues should • Benign prostatic hypertrophy • Bladder calculi be considered. While spinal cord injury with parapa- • Bladder clots resis or quadraparesis is usually obvious, other enti- • Meatal stenosis ties such as require a higher • Neoplasm of the bladder index of suspicion. • Neurogenic etiologies • Paraphimosis Physical Examination • Penile trauma The general appearance of patients presenting to • the ED with AUR varies greatly, depending on the • Prostate etiology, age, and underlying comorbidities of the • Prostatic trauma/ avulsion • Prostatitis patient. A rectal examination is important in both • Urethral foreign body men and women. In women, a rectal examination • Urethral inflammation should be performed to rule out rectal or uterine • Urethral strictures prolapse. In men with BPH, the prostate may be enlarged; however, a normal prostate examination does not exclude BPH. The prostate in a patient with Table 3. Gender-Specific Causes Of Acute is generally enlarged and nodular. Urinary Retention1,23,33 One meta-analysis by Roehrborn et al found that prostate volumes estimated by digital rectal ex- Women Men amination and measured by transrectal ultrasound • Obstructive Causes • Obstructive Causes (TRUS) were significantly correlated (r = 0.4-0.9), l l Cystocele BPH but it also concluded that digital rectal examination l l Tumor Meatal stenosis often underestimates prostate size if TRUS volume l • Infectious Causes Phimosis/ paraphimosis is > 30 mL. However, digital rectal examination may • Operative Causes l Tumor still help identify patients with likely to 32 • Infectious Causes be larger than certain cutpoints by TRUS. Patients • Operative causes with prostatitis often present with a tender, warm, and boggy prostate. It is common practice to avoid Abbreviation: BPH, benign prostatic hypertrophy.

Emergency Medicine Practice © 2014 6 www.ebmedicine.net • January 2014 performing digital rectal examinations in patients Clinical judgment should be used in each case to with suspected acute bacterial prostatitis, so as not determine the significance of obtaining a chemistry to elicit bacteremia. However, we could find no panel to evaluate renal function. Prostate-specific significant evidence supporting this widely accepted antigen (PSA) levels are frequently elevated in the 34,35 notion and it remains an area for further study. setting of AUR; however, PSA is not a routine In both sexes, a thorough genital/pelvic exami- ED test and will not differentiate cancer from other nation is necessary. In men, the examination looks causes of urinary retention. Complete blood count for phimosis or paraphimosis, lesions, and tumors as (CBC) should be considered in patients with sus- potential causes of AUR; in women, the examination pected serious infection, hypovolemia, or hemato- looks for lesions, tumors, uterine prolapse, cystocele, logic disorders. enlarged uterus, or enlarged ovaries. If there is clini- cal suspicion for neurogenic disease or a history of Imaging Studies trauma, it is important to perform a thorough neuro- In both men and women, when obstruction is the logical examination, focusing on strength, sensation, likely cause of urinary retention, renal ultrasound and lower extremity reflexes. When ruling out spinal may show signs of , stone, or ob- pathology as a cause for AUR, one must assess the struction. Kidney ultrasound can evaluate for bulbocavernosus reflex, anal reflex, sphincter tone, hydronephrosis that would indicate downstream and perineal sensation. obstruction. (See Figure 2.) In women, pelvic ultra- sound using the bladder sonographic window may Diagnostic Testing

Laboratory Tests Figure 2. Ultrasound Images Of The paramount test in patients with AUR is the Hydronephrosis urinalysis. A urinalysis will reveal infection and determine the presence of , which can be a sign of infection, tumor, toxin, trauma, or calculi. A The 3-cup bacterial localization study, described initially by Mears and Stamey in 1968, has been the classic method for diagnosis of bacterial prostatitis 36 in men. The patient is asked to retract the foreskin, cleanse the meatus, and void, collecting the first 5 Renal parenchyma to 10 mL of urine. This first cup represents bacte- rial growth from the urethra. Then, the next 100 to Dilated renal pelvis 150 mL of urine is voided, and 5 to 10 mL of that is collected in a second cup, representing the bladder component of bacterial growth. The prostate is then massaged until a drop of fluid is expressed, collect- ed, and then examined by microscope. More than 10 white blood cells per high power field is abnormal and is consistent with prostate inflammation. Lastly, the third cup captures the first 5 to 10 mL of urine collected after prostate massage, and this is sent B 37 for culture, representing a prostatic source. Clini- cally, the 3-cup test has proven time-consuming and Renal parenchyma cumbersome, and its use as a diagnostic tool is de- Dilated renal clining. Simply obtaining urine cultures before and pelvis after prostate massage has become a clinically useful alternative. A 2009 retrospective study by Magri et al of semen cultures from 1100 patients found that it can be a useful adjunctive diagnostic tool; however, further studies are needed to confirm these findings and determine whether a semen culture alone may 37 represent a reasonable diagnostic alternative.

Electrolytes, blood nitrogen, and creati- nine levels may be obtained to evaluate for im- paired renal function from prolonged obstruction and potential electrolyte imbalance in those requir- Images show hydronephrosis in a 21-year-old male eventually ing bladder irrigation. diagnosed with nephrolithiasis. Image A shows mild hydronephrosis. Image B shows moderate hydronephrosis.

January 2014 • www.ebmedicine.net 7 Emergency Medicine Practice © 2014 show masses (such as ovarian or uterine tumors). to the circumference of the catheter, not the diameter Bladder ultrasound can assess for free fluid in cases of the lumen. are recorded in sizes French, of trauma, and it can assess bladder volume and where 1 French (F) = 1 Charrière = 0.33 mm. Sizes reveal the presence of urethral jets (which would for adults range from 10F to 28F, with sizes 14F to rule out upstream ureteral blockages). Bladder 18F being the most common. Large-circumference ultrasound can also demonstrate urinary retention catheters (eg, 16F-20F) are more beneficial for drain- (see Figure 3), confirm correct Foley or suprapubic ing clots, debris, mucus, etc. catheter placement, and can also detect the presence After examining the urogenital area and prior to of masses. starting the procedure, observe the patient’s over- Regarding renal function testing in blood all condition. Palpate the suprapubic area, keeping chemistries, in an observational cohort study of 96 in mind the contraindications to Foley and Coude subjects (11 female and 85 male), Shah et al showed catheter insertion. (See Table 5.) For patients with that the presence of hydronephrosis on bedside ul- recent bladder or prostate surgery where continu- trasound does not correlate with an elevated serum ous bladder irrigation may be necessary, consider creatinine; a sensitivity of 70%, a specificity of 67%, placement of a double or triple lumen catheter by a positive predictive value of 39%, and a negative an emergency clinician trained in advanced catheter predictive value of 70% were found. This study techniques. See Figure 4 for a picture of types of noted that, given the high prevalence of an elevated urinary catheters. creatinine in this cohort of subjects, emergency phy- To facilitate passage of a Foley catheter in men, sicians interested in identifying creatinine elevation hold the penis at a 90° angle to the stretcher and in patients with AUR should maintain a low thresh- stretch it upward to straighten the penile urethra. 33 old for testing the serum creatinine. As in women, ensure adequate lubrication with 1 to In cases where masses or malignancy are suspect- 2 mL of lubricant inserted into the urethral meatus. ed causes of AUR, further diagnostic study (such as Apply gentle continuous pressure to help open computed tomography [CT] scan) should be under- the prostatatic sphincter, as attempting to force it taken to evaluate for mass or malignancy as a cause through can increase sphincter contraction, making of obstruction. When new neurological deficits are Foley passage difficult. While waiting for sponta- elicited on examination in a patient with AUR, mag- neous urine return, a 60-mL syringe may be used netic resonance imaging (MRI) is indicated. A lumbar to aspirate urine; if there is still no urine return, MRI is indicated for suspected disc herniation, cord remove the Foley and attempt again under direct compression, and cauda equina syndrome. ultrasound guidance. Ultrasound can be useful in confirming placement as well as calculating urinary Treatment volume (postvoid residual) prior to catheter place- ment. Do not inflate the balloon until you have AUR should initially be managed by immediate and complete decompression of the bladder through Figure 3. Transverse View Ultrasound Image with a double-lumen Foley 22 Of A Full, Distended Bladder catheter. (See Table 4 for a list of types of catheters and their uses.)

Foley Placement Two important aspects in Foley placement are patient reassurance and patient comfort during the procedure. In female patients, this is especially im- Distended bladder portant, given the common propensity to tense the muscles, especially if the patient has had prior expe- riences with painful Foley insertion. In a prospective study of 50 patients, Allardice et al examined the importance of adequate analgesia, preparation, and correct technique. It was found that by using these methods, 50 consecutive male patients with a diag- nosis of AUR were successfully catheterized by 12 43 different house persons. Often, adequate explana- tion regarding the procedure and having the patient exhale deeply during insertion helps greatly. When inserting a Foley catheter, the small- Bladder wall est catheter size that will allow for adequate urine drainage should be used. Urinary catheter sizes refer

Emergency Medicine Practice © 2014 8 www.ebmedicine.net • January 2014 confirmed placement with urine return. Inflate the • Suspected genitourinary trauma (eg, urethral balloon only with sterile water to ensure the bal- injury) loon does not float or become lodged against the • or sepsis bladder wall.1 • Precipitated acute urinary retention If the above fails (usually due to hindrance of • Uncontrolled hematuria passage by an enlarged prostate), placement of a curved-tip Coude catheter (see Figure 4) by an emer- At this time, there is no current indication of gency clinician comfortable with advanced catheter- usage of a Coude catheter in women presenting with 38 ization techniques is warranted for male patients. AUR, due to lack of curvature of the urethra and The curved tip of the Coude catheter allows easier absence of a prostate. passage over the obstruction caused by prostatic In situations involving difficult Foley insertions enlargement. Despite a thorough literature search, in women, the emergency clinician should first ex- no studies were found on placement of Coude amine for , cystocele, or signs of prolapsed catheters by emergency clinicians other than articles organs. Look for the urethral meatus first, instead recommending its use in the setting of difficult Foley of attempting to put the catheter where the meatus catheter placement due to an enlarged prostate. If should be, especially in elderly women. If the vagina passage of neither catheter is successful, a is accidently catheterized, do not remove the catheter; consult should be obtained. Criteria for ordering a leave it in the vagina so that, when you start to recath- urology consult include the following: eterize with the second tube, you will know where • Urologic postoperative complications not to put it. Ensure adequate lubrication by placing • Failed Foley and Coude catheter placement lubricant on the catheter, as well as slowly injecting 1 • , meatal stenosis to 2 mL into the urethral meatus. This helps provide 1 lubrication further up the urethra.

Table 4. Types Of Urinary Catheters Suprapubic Catheterization Indications for suprapubic catheterization include: (1) AUR in a patient who has contraindications for • Single lumen: no balloon; used for in-and-out catheterization urethral catheterization, (2) major urethral trauma • Double lumen: balloon-inflation lumen and draining lumen; used for continuous catheterization when no urologist is available, and (3) failure of Foley and Coude catheterization in an AUR patient • Triple lumen: also called 3-way catheters; have draining lumen, 1 balloon-inflation lumen, and irrigation lumen for bladder washout; without contraindications. Prior to performing the commonly used in post-TURP patients procedure, ultrasound visualization of the bladder should be performed to confirm bladder disten- Abbreviation: TURP, transurethral resection of prostate. tion. Emergency clinicians should also be familiar with the absolute and relative contraindications as well as the indications for performing suprapubic Table 5. Indications And Contraindications For Catheter Placement

Indications for Foley Placement Figure 4. Types Of Urinary Catheters • Acute urinary retention • Need for monitoring urine output • Collection of urine for diagnostic purpose • Radiographic evaluation of lower urinary tract • Treatment of neurogenic bladder

Indications for Coude Placement • Failed Foley placement • Benign prostatic hypertrophy and known history of difficult catheter- ization

Relative Contraindications to Foley Placement/Contraindications for Coude Placement • Abdominal or pelvic trauma with blood at urethral meatus • Penile deformity • High-riding prostate • Perineal hematoma • Known impassible catheterization • Radiographic evidence of bladder mass/ trauma Top: triple-lumen urinary catheter; center: double-lumen Coude cath- • History of known prostate or bladder neck surgery eter; bottom: double-lumen urinary catheter.

January 2014 • www.ebmedicine.net 9 Emergency Medicine Practice © 2014 catheterization. (See Table 6.) Also, keep in mind Medical Therapies that a misplaced suprapubic catheter may produce Since 1994, there have been major changes in the 34 an ileus, bleeding, hematoma, or infection. Us- treatment of patients with urinary retention, in ing ultrasound guidance for direct visualization is particular, patients with lower urinary tract symp- highly recommended, as shown by Aguilera et al in toms and BPH. Currently, the American Urologi- a prospective study that showed 100% success rate cal Association guidelines treatment options for when ultrasound guidance was used in placing 17 patients with modest-to-severe lower urinary tract 39 suprapubic catheters in the ED. For instructions on how to place a suprapubic catheter, see Table 7. In a meta-analysis study by McPhail et al, Table 6. Indications And Contraindications postabdominal surgery patients who had bladder For Suprapubic Catheter Placement drainage via suprapubic catheters had a decreased risk of bacteriuria and less discomfort than patients Indications for Placement who had transurethral catheterization. The supra- • AUR in a patient with contraindications for urethral catheterization pubic catheter was, overall, preferred by patients • No urologist present 40 versus transurethral catheterization. A Cochrane • Failure of transurethral catheterization in an AUR patient Database review was performed to determine pa- Absolute Contraindications for Placement tient preference and policies for catheter placement • Gross or morbid obesity in patients with short-term voiding problems and 41 • Pregnancy bladder drainage problems. One Cochrane article • Bladder not palpable and/or not visible on portable ultrasound confirmed patient preference for suprapubic cath- eterization by concluding that in patients requiring Relative Contraindications for Placement catheterization for up to 14 days, less bacteriuria, • Uncontrolled coagulopathy less discomfort, and reduced need for recatheteriza- • Pediatric cases (urologist input necessary) tion were experienced by patients when suprapubic • Prior abdominal or pelvic surgery (may need consult first, given the catheters were used compared to when urethral risk of adhesion) 42 catheters were used. • Pelvic radiation

Complications Of Catheterization Abbreviation: AUR, acute urinary retention. Hematuria, hypotension, and postobstructive diure- sis are all potential complications of rapid bladder Table 7. Procedure For Placement Of A decompression in patients with AUR. Nyman et Suprapubic Catheter al performed a review of the literature on urinary decompression published from 1966 to 1996 and found that, although evidence showed that a sudden 1. Identify location 2 finger-breadths above the pubic symphysis reduction in bladder wall tension reflexively pro- and anesthetize with 1% lidocaine with epinephrine. 2. Insert a 22-gauge spinal needle into the midline and aimed duces vasodilatation with a concomitant decrease in caudally. , this occurs with no serious clinical 3. Advance until urine is aspirated (return of air suggests bowel consequences when a patient already has a healthy penetration; movement cephalad with the needle is recom- cardiovascular system. Patients without a healthy mended); then place a wire through the needle and remove the cardiovascular system may be at risk for prolonged needle. hypotension following rapid bladder decompres- 4. After aspiration, make a 1-cm skin incision deep through the 22 sion. In the past, to avoid the aforementioned subcutaneous fat. sequelae, it was recommended to only gradually 5. Incise the fascia, ensuring a wide enough incision to allow trocar decompress the bladder in treating patients with placement AUR. Nyman's review cast doubt on this common 6. Inspect the trocar to make sure it can be easily removed from the practice, finding no evidence that gradual bladder sheath. 7. Insert the trocar, with sheath, into the bladder using a “cork- decompression decreased the likelihood of causing screw” motion until urine flashback is seen; advance 1 cm further these complications, and complete and rapid empty- 22 to ensure safe placement within the bladder. ing of the bladder was recommended. 8. Remove the trocar from the sheath and place the catheter down Other complications of catheterization include the lumen of the sheath into the bladder. a risk of urethritis, cystitis, prostatitis, bactere- 9. Remove the tear-off strip from the sheath and remove the mia, and sepsis. These risks are most prominent sheath. in elderly patients and patients with preexisting 10. Inflate the balloon. indwelling catheters. 11. Suture in place.

Note: If the above catheter is not available, a central venous catheter set may be used, with 12- to 18-inch tubing inserted into the bladder using Seldinger technique.

Emergency Medicine Practice © 2014 10 www.ebmedicine.net • January 2014 symptoms associated with BPH include: (1) watch- tant use of an indwelling catheter, an ful waiting, (2) pharmacotherapy with alpha block- (such as alfuzosin, , or doxazosin), and 6 ers such as doxazosin or tamsulosin (which act to then trial without catheter. Adverse side effects relax urethral muscle), and (3) minimally invasive commonly reported with different alpha 1 blockers therapies such as transurethral microwave thera- include , headache, postural hypotension, 44 py. Generally speaking, most patients will now rhinitis, and sexual dysfunction, and these occur in 6 undergo medical management prior to any form about 5% to 9% of patient populations. of surgical intervention. Before these changes, all patients with hematuria were treated with surgical 5-Alpha Reductase Inhibitors intervention; today they are first offered pharmaco- The current American Urological Association guide- therapy. (See Table 8.) lines regarding 5-alpha reductase inhibitors recom- mend them as an effective and appropriate option Pharmacologic Therapies for treating men with enlarged prostates and associ- 44 The 2 mainstays of pharmacological treatment in ated lower urinary tract symptoms. The Proscar BPH-precipitated AUR are alpha 1 adrenergic- Long-Term Efficacy and Safety Study (PLESS) trial, blocking agents (such as tamsulosin) and 5-alpha a multicenter double-blinded, placebo-controlled reductase inhibitors (such as ). Alpha 1 trial, studied 3000 men with enlarged prostates and adrenergic blockers work to block alpha-adrenergic moderate-to-severe urinary symptoms over 4 years. receptors in the prostate and bladder neck, thus The patients were randomized to finasteride 5 mg/ decreasing bladder outlet resistance and facilitating day or placebo. Finasteride treatment resulted in normal micturition.17 The 5-alpha reductase inhibi- significant improvement in the symptoms scores tors act by inhibiting the formation of dihydrotes- (-3.3 in the finasteride group compared to -1 in the tosterone (the chemical responsible for androgenic placebo group in the first year [P < .001]), and main prostate growth) from testosterone by blocking the prostate volume decreased in the finasteride group enzyme 5-alpha reductase.15 (-18%) in the first year. At 4 years, the risk of un- dergoing BPH-related surgery was reduced by 55% Alpha-Adrenoceptor Antagonists in the finasteride group versus the placebo group, The Prospective European Doxazosin and Combi- and the risk for experiencing AUR in the finasteride 46 nation Therapy (the PREDICT study) concluded group was reduced by 57% (P < .001). that doxazosin is effective in improving urinary In the trials, a pooled analysis of 3 symptoms and urinary flow rate in men with BPH similar randomized double-blind placebo-controlled and more effective than placebo or finasteride 2-year clinical trials was similar to PLESS, but it alone. The addition of finasteride did not provide had a larger patient population (n = 4325). These additional benefit to that achieved with doxazosin trials showed that treatment with 0.5 mg of dutas- 45 alone. Therefore, it is common for patients with teride once daily reduced the risk of AUR and BPH urinary retention to be treated with the concomi- more than placebo. At 2 years, dutasteride therapy

Table 8. Pharmacologic Therapies Used For Spontaneous Acute Urinary Retention In The Emergency Department

Class of Drug Generic Name/ Dosing Mechanism of Action Indications Side Effects* Alpha blockers • Tamsulosin: 0.4-0.8 mg daily Alpha 1 adrenergic Patients with spontaneous Postural hypotension, • Alfuzosin: 10 mg PO once daily blockade, thus increasing AUR regardless of prior headache, dizziness, • Doxazosin: 1-8 mg PO once daily urinary flow rate history of usage (unless fatigue, nausea, constipa- • : 1-10 mg PO once daily contraindicated*) tion • : 8 mg PO once daily; decrease to 4 mg PO once daily if CrCl is < 50 mL/min • Prazosin: 1-2 mg PO twice daily† 5-alpha reductase • Finasteride: 5-mg tablets Decreases the formation Patients with spontaneous Impotence, decreased inhibitors • Dutasteride: 0.5-mg capsules of testosterone into dihy- AUR who are currently , decreased ejacula- drotestosterone, reducing on or have previously tory volume, testicular prostate growth taken 5-alpha reductase pain, rash, pruritus inhibitors for BPH (unless contraindicated*)

*For full list of side effects and contraindications please visit www.FDA.gov/Drugs/ †Not approved by the United States Food and Drug Administration for this use. Abbreviation: AUR, acute urinary retention; BPH, benign prostatic hypertrophy; CrCl, creatinine clearance; PO, per os (by mouth). Sources: www.FDA.gov, www.merckmanuals.com

January 2014 • www.ebmedicine.net 11 Emergency Medicine Practice © 2014 Clinical Pathway For The Treatment Of Acute Urinary Retention In Women

Perform history and physical examination

Physical findings of Signs of urethral or • Recent gynecological or No sign of obstruction vesicular lesions, bladder trauma obstetric surgery infection, or severe pain or • Rectal mass, ure- terocele, or cystocele present

Treat pain and underlying • Place ultrasound-guid- Perform ultrasound Consult urology cause ed suprapubic catheter* • Consult obstetrics/gy- necology

Distended bladder Reassess ability to void NO Assess other causes Admit present?

NO YES

Insert single- or dual- Able to void? lumen Foley catheter

YES

Arrange disposition Successful? NO Consider using a smaller accordingly Foley catheter or more experienced operator YES

Is there presence of 1 or more?: • Severe infection Order urinalysis, consider Urology consult service • Significant comorbidity YES Successful? NO ordering BUN, creatinine, present? • Impaired renal function and CBC • Neurological deficits NO YES • Catheter complication

YES • Place ultrasound-guid- NO Consult urology ed suprapubic catheter* (Class II) Admit • Admit Able to void? NO

YES

* Contraindications should be assessed prior to suprapubic catheter • Discharge home insertion, and it should only be attempted by or in the presence of a • Treat or discontinue offending agent urologist or by a provider only when consult service unavailable. • Arrange appropriate follow-up Abbreviations: BUN, blood urea nitrogen; CBC, complete blood count.

See class of evidence definitions on page 14.

Emergency Medicine Practice © 2014 12 www.ebmedicine.net • January 2014 Clinical Pathway For The Treatment Of Acute Urinary Retention In Men

Perform history and physical examination

Enlarged prostate History of urethral Nonenlarged Signs of urethral Recent urological present stricture or known prostate present or bladder operation impassible Foley trauma (ie, TURP) catheter

• Place ultrasound-guided suprapubic catheter* Perform ultrasound (Class I) Consult urology (Class II) • Consult urology

Distended bladder? Admit YES NO

Insert Foley Assess other catheter (class I) causes

Consider using smaller Foley Successful? NO NO Insert Coude catheter catheter or more experienced Successful? (Class I) operator YES

Order urinalysis (Class I), YES YES Successful? consider ordering BUN, creatinine, and CBC NO

Is there presence of 1 or more?: Urology consulta- Consult urology YES tion service • Severe infection YES Admit • Significant comorbidity present? • Impaired renal function NO • Neurological deficits • Voiding pres- • Catheter complication ent: discharge • Etiology other than BPH NO Precipitated YES home, discon- • Place ultra- cause likely? tinue offending sound-guided agent, treat suprapubic other precipitat- catheter* ing cause (Class II) • Leave Foley in (Class I) • Voiding absent: • Admit • Place a hip bag NO admit • Arrange follow-up • Prescribe alpha blocker (Class I) • Discharge home * Contraindications should be assessed prior to suprapubic catheter insertion and it should only be attempted by or in the presence of a urologist or by a provider only when consult service is unavailable. Abbreviations: BPH, benign prostatic hypertrophy; BUN, blood urea nitrogen; CBC, complete blood count; TURP, transurethral resection of prostate. See class of evidence definitions on page 14.

January 2014 • www.ebmedicine.net 13 Emergency Medicine Practice © 2014 reduced the risk of BPH-related surgery by 48% and those treated with dutasteride or combined therapy 47 AUR by 57% compared to placebo (P < .001). (P < .001). Prevention of AUR secondary to BPH In both the finasteride and dutasteride trials, may be achieved by long-term treatment (4-6 years) drug-related sexual adverse events (such as de- with dutasteride, finasteride, or a combination of fin- 46,47,50 creased libido, impotence, ejaculatory disorders, asteride and doxazosin. The current American gynecomastia, and rash) occurred more frequently Urological Association guidelines only recommend in the 5-alpha reductase inhibitor groups than in the using the 5-alpha reductase inhibitors (finasteride placebo groups. In both finasteride and dutasteride, and dutasteride) in men with considerable prostate the onset of adverse effects appeared in the first enlargement on digital rectal examination. year, and there was no evidence of increased ad- verse effects compared to placebo after the first year Antibiotics of therapy. Both agents appeared to be reasonably In addressing the case for giving antibiotics, it is 48 safe and well tolerated. important to first recognize what is being treated. If only a catheter has been placed and there is no Combination Therapy Trials suspicion for concomitant infection, prophylac- The Medical Therapy of Prostatic Symptoms Study tic antibiotics should not be initiated unless the (MTOPS) was a long-term, double-blind trial that patient is pregnant or preoperative, as antibiotics 51 compared the effects of placebo, doxazosin, finaste- have been found to promote organism resistance. ride, and combination therapy on measures of the A Cochrane review article found that silver alloy- 49 clinical progression of BPH over 4 years. The trial impregnated urethral catheters were associated with 41 followed 3047 men at 17 clinical centers between decreased rates of UTI versus standard catheters. 1993 and 1998. Men aged ≥ 50 years with a symptom In suspected acute or chronic bacterial prostatitis, score of 8 to 30 and a maximum urinary flow rate a 4- to 6-week course of a fluoroquinolone (such as between 4 and 15 mL/sec with a voiding volume of levofloxacin) is the first-line treatment. Adjunctive at least 125 mL were included in the study. Exclu- therapy for prostatitis includes alpha blockers, 5-al- 52 sion criteria included men with prior medical and/ pha reductase inhibitors, and NSAIDs. or surgical intervention for BPH, patients who were hypotensive while supine, and those with a Controversies And Cutting Edge PSA > 10 mg/mL. The results of this study showed that combination therapy with both doxazosin and Rapid Versus Gradual Decompression finasteride was safe and reduced the risk of overall Addressing the complications of hematuria, postob- clinical progression of BPH significantly more than structive diuresis, and hypotension after rapid blad- treatment with either drug alone. In all groups, der decompression, Nyman et al found no evidence the risk of AUR increased with increasing PSA 49 to support the practice of gradual bladder decom- levels. Furthermore, the Combination of Avodart pression (clamping after a 705-mL urine output) in and Tamsulosin (CombAT) trial was a multicenter order to prevent complications. They concluded that randomized double-blind study of clinical outcomes the potential complications of rapid bladder empty- in 4844 men with symptomatic BPH who received ing were rarely clinically significant, and they empha- either tamsulosin 0.4 mg, dutasteride 0.5 mg, or a sized the importance of supportive care for all AUR combination of both. After 4 years, the study found patients, with particular attention paid to the special that the incidence of AUR or BPH-related surgery needs of elderly, cardiovascularly compromised, and was higher in men treated with tamsulosin than in 22 hypovolemic patients.

Class Of Evidence Definitions

Each action in the clinical pathways section of Emergency Medicine Practice receives a score based on the following definitions.

Class I Class II Class III Indeterminate • Always acceptable, safe • Safe, acceptable • May be acceptable • Continuing area of research • Definitely useful • Probably useful • Possibly useful • No recommendations until further • Proven in both efficacy and effectiveness • Considered optional or alternative treat- research Level of Evidence: ments Level of Evidence: • Generally higher levels of evidence Level of Evidence: • One or more large prospective studies • Nonrandomized or retrospective studies: Level of Evidence: • Evidence not available are present (with rare exceptions) historic, cohort, or case control studies • Generally lower or intermediate levels • Higher studies in progress • High-quality meta-analyses • Less robust randomized controlled trials of evidence • Results inconsistent, contradictory • Study results consistently positive and • Results consistently positive • Case series, animal studies, • Results not compelling compelling consensus panels • Occasionally positive results

This clinical pathway is intended to supplement, rather than substitute for, professional judgment and may be changed depending upon a patient’s individual needs. Failure to comply with this pathway does not represent a breach of the standard of care. Copyright © 2014 EB Medicine. 1-800-249-5770. No part of this publication may be reproduced in any format without written consent of EB Medicine.

Emergency Medicine Practice © 2014 14 www.ebmedicine.net • January 2014 Mustonen et al further supported the impor- Pre-Foley Insertion Balloon Testing tance of urgent decompression in a prospective Whether it is necessary to test the balloon for study of 25 patients. They concluded that AUR patency prior to urethral catheterization remains caused decreased renal blood flow (increase in resis- uncertain. Pretesting the balloon ensures it is sym- tive index) as measured by renal Doppler ultra- metrical, that it inflates without leaking, and that it sound. In two-thirds of patients, blood flow returned deflates. Negative effects of balloon testing include to normal with treatment of the precipitating factor balloon cuffing, the formation of ridges or creases, of AUR. However, in the remaining one-third of pa- and the possibility of urethral trauma and balloon 60,61 tients, at 1 month and 6 months, blood flow was still entrapment. decreased, thus stressing the importance of timely A review of practice guidelines by Barnes et al decompression and urgent treatment of the AUR looked at 3 catheters in a laboratory setting and 4 in 53 precipitating factor. a clinical setting and found a substantial increase in resultant diameter with pretesting (inflation and de- Trial Without Catheter Following Acute flation), which could make catheter placement more 60 Urinary Retention difficult. Moreover, a review article found that the The answer to the question, "How long should the collapse of the balloon during inflation and deflation catheter stay in?" remains elusive. A 1982 prospec- results in ridges or cuff formation, which can result tive study of 107 patients by Breum et al found in urethral trauma and make atraumatic removal of 61 that up to 70% of men had a recurrent episode of the catheter difficult or even impossible. Another AUR within 1 week if the bladder was drained conclusion of this article was that there is a growing 54 only initially on presentation. A 1989 random- (but still limited) evidence base for managing pa- ized control trial by Taube et al of 60 patients, with tients with Foley catheters, leaving many questions times of catheter removal of 0, 24, or 48 hours, found unanswered. Until these and other questions are that there was no correlation between the time of answered, recommendations are to carefully apply catheter removal and the likelihood of spontane- clinical guidelines, regularly review existing evi- 55 ous voiding. In 2006, in an observational study dence, and ensure that institutional protocols follow 61-63 of 2618 patients, Desgrandchamps et al found that the manufacturers' guidelines. men with BPH and AUR catheterized for ≤ 3 days Future areas of research in this area could had greater success with spontaneous voiding than include cost and prevalence studies, studies on 56 those catheterized for > 3 days. The 2003 American adequate volumes of prefill, “gravity drainage” Urological Association guidelines recommend at versus manual aspiration, slow versus fast catheter least 1 attempt at voiding after catheter removal in removal, and usage of silicone versus latex catheters. a BPH patient before considering surgical interven- 44 tion. In a 2006 prospective cross-sectional survey of Managing The Entrapped Foley Catheter 6074 patients, Fitzpatrick et al showed that pro- One potential complication of Foley catheter remov- longed catheterization (> 3 days) did not influence al is entrapment of the catheter as a result of balloon trial without catheter success, but it was associated malfunction, a faulty valve mechanism, malfunction 57 with increased morbidity. A 2004 and 2005 pro- of the inflation channel, or crystallization of fluid spective study showed that men with BPH have a within the balloon. This often becomes evident as a greater chance of a successful voiding trial without failure to deflate despite manipulation and repeated catheter at 2 to 3 days if they are treated with alpha- attempts at fluid aspiration. Often, this phenomenon adrenergic blockers for 3 days, starting at the time of is due to cuffing, which happens after complete 58,59 catheter insertion. removal of fluid contents from the catheter balloon. The PLESS study classified patients into 2 This cuff can attach on to soft tissue within the blad- groups: ”spontaneous“ AUR and ”precipitated“ der or urethra. This can be avoided by 2 techniques. AUR. Patients with spontaneous AUR had no evi- The first techniques is by very slow deflation of the dence of precipitating factors other than BPH, while catheter balloon or by passive deflation with the sy- patients with precipitated AUR (in addition to BPH) ringe. The second technique is instilling 0.5 to 1 mL had clinical evidence of other precipitating factors of water back into the balloon after complete evacu- such as: (1) UTI, (2) preceding surgery, (3) predis- ation of fluid contents from the balloon, eliminating posing medication exposure, or (4) inciting medical the already-formed balloon cuff and smoothing the 63 event. Outcomes showed that patients with spon- retaining ridge. taneous AUR had a higher rate of recurrent spon- If the Foley still cannot be removed after follow- taneous AUR and a greater need for BPH surgery ing the above procedures, the next step is to confirm than patients with precipitated AUR (in whom trial placement in the bladder, using bedside ultrasound, without catheter immediately after bladder drainage and then to cut the balloon port proximal to the 46 can be attempted). inflation valve. A review by Hollingsworth et al of 13 patients with Foley balloon malfunction found that

January 2014 • www.ebmedicine.net 15 Emergency Medicine Practice © 2014 this technique was successful in 31% of their cases.65 Prevention of AUR recurrences over 4 to 6 years If this method fails, there is, most likely, a more distal in men with BPH may also be achieved by long- obstruction that may be fixed by inserting a fine- term management with finasteride in patients with gauge guidewire through the inflation channel. If the enlarged prostates on clinical examination; however, blockage persists after guidewire insertion, the next we recommend that this medication be started by a step is to thread a 22-gauge central venous catheter physician who can provide follow-up. over the wire and remove it when the catheter tip is Lastly, because of the increased risk of morbid- in the balloon, allowing for drainage.64 This technique ity (as shown by Fitzpatrick et al) and the poorer was successful in 15% of Hollingsworth et al’s cases.65 success rates for spontaneous voiding (as shown by If all of these methods are unsuccessful, the Desgrandchamps et al), urge patients to consult a balloon may be dissolved chemically using 10 mL urologist within 3 days. At this follow-up appoint- of mineral oil and waiting 15 minutes. This can be ment, the need for further urodynamic studies, repeated only once, if needed. The most extreme laboratory studies such as PSA levels, and addi- and final methods described in the literature involve tional pharmacotherapy (such as 5-alpha reductase active rupture of the Foley balloon with a sharp in- inhibitors) may be discussed with the patient.32 strument. These numbered 31% of Hollingsworth et AUR secondary to precipitated causes are at lower al’s cases. Some approaches include transabdominal, risk of recurrence and, thus, might benefit from transvaginal, transperineal, and transrectal punc- trial without catheter in the ED directly after blad- ture of the catheter balloon using ultrasonography. der drainage. See Table 9 for recommendations on Due to the risk of bladder rupture and severe pain, outpatient treatment and follow-up for patients dis- hyperinflation of the balloon with either air or saline charged from the ED who present with AUR. is not recommended.64 Complications of chronic catheter placement 68 include UTI, ureteral stones, trauma, and stricture, Disposition and these complications have been independently 67 associated with an increased risk of mortality. AUR patients with concomitant infection, signifi- However, it is still important to keep in mind that cant comorbid illnesses, impaired renal function, early removal of urinary catheters is associated with neurological deficits, or complications of catheter- a higher risk of recurrent AUR, so catheters should ization require emergent urological consultation remain in place until the patient can visit a urologist 66 and likely admission. as an outpatient. Because of the 70% recurrence rate of spontane- ous AUR in patients with BPH, the catheter should Summary be left in place at discharge from the ED. One retro- spective review of 1257 patients found that 90% of AUR in men is a very common syndrome that is patients with AUR in the ED are discharged home frequently diagnosed and managed in the ED. While with a catheter in place to await further intervention there is a vast array of published material on the 67 from a urologist in an outpatient setting. incidence, etiology, and treatment of AUR in men, Return parameters (such as fever, penile pain, with the exception of few case reports, there is very repeated vomiting, abdominal pain, and catheter little published on the treatment of women with blockage) as well as instructions on hip/leg bag and Foley care, should be discussed and verbalized by the patient. In patients discharged with indwell- Table 9. Recommendations On Outpatient ing catheters, prophylactic antibiotics should not Treatment And Follow-Up For Patients be initiated, as they have been found to promote Discharged From The Emergency organism resistance (unless the patient is pregnant Department With Either Spontaneous Or or preoperative).51 Among patients discharged with Precipitated AUR indwelling catheters, bacteriuria often develops, but Sources of AUR it is typically asymptomatic.51 AUR Therapies Benign Prostatic Precipitated Causes Regarding pharmacological treatment, an alpha Hypertrophy blocker (such as tamsulosin) should be started in Medications Prescribe alpha block- Prescribe antibiotics, patients with AUR secondary to BPH prior to dis- ers if needed charge from the ED not only because of improved urinary symptoms and flow rate, but because of the Catheters Leave in place Remove, if passed voiding trial in ED increased chance of successful voiding at days 2 to 3. Remember to explain the increased risks of ortho- Follow-up See urologist within 3 At discretion of ED days clinician static hypotension with the use of alpha blockers, especially in the elderly. Abbreviations: AUR, acute urinary retention; ED, emergency department.

Emergency Medicine Practice © 2014 16 www.ebmedicine.net • January 2014 AUR, and this remains a small but important area Case Conclusions for research. Due to the wide variety of symptoms for sus- In the case of the 66-year-old man with hypertension and pected AUR in the ED, a careful history and physical high cholesterol, after you performed a thorough head-to- examination are vital. In men and women, thorough toe examination and a complete history, you performed a genital, pelvic, and rectal examinations are needed rectal examination, which showed good rectal tone with to assess for emergent precipitators of AUR. Ultra- an enlarged, smooth prostate. You used bedside ultra- sound may be used diagnostically and therapeuti- sound to evaluate the bladder and saw a full, distended cally in aiding invasive catheter placement, and bladder with an approximate volume of 1100 mL. Urgent also as a cost-saving measure. While most labora- bedside complete bladder decompression was performed tory studies may be ordered at the discretion of the with a 16F dual-lumen Foley catheter, and urine was sent emergency clinician, most patients may only require for urinalysis and culture. The patient’s symptoms im- urinalysis. Once AUR is identified, patients should proved, his vital signs remained stable, and the urinalysis be treated with prompt and total bladder decom- returned as normal. You arranged a urology follow-up pression, with utilization of a Coude catheter if a appointment in 3 days, had the Foley bag changed to a Foley catheter cannot be passed. hip bag, and gave the patient care and changing instruc- When considering patient admission versus tions. You prescribed him a 2-week course of doxazosin discharge, the emergency clinician should consider and discharged him home with return instructions if his patient comorbidities and precipitating factors. condition worsened. In precipitated cases of AUR, the catheter can be In your second case, the 72-year-old man, a quick removed and a voiding trial performed prior to physical examination revealed only a distended bladder. discharge from the ED. When BPH is the cause, the A urethral catheter was placed, and 700 mL of urine was urinary catheter should be left in, an alpha blocker obtained, with much relief for the patient. Not forget- prescribed, and urology consultation arranged ting the patient’s presentation and his stumble while within 3 days. As always, patient and family educa- changing stretchers, you decided to perform a thorough tion, with discharge instructions for Foley care and neurological examination, and you found nearly absent leg bag emptying, are of the utmost importance. rectal tone and absence of sensation and vibration below T11. Urgent MRI confirmed your diagnosis of spinal cord compression. You consulted neurosurgery, and the patient was admitted for decompressive laminectomy and eventual chemotherapy. In the third case, the 46-year-old febrile woman with HIV, after taking her history and giving her a thorough Time- And Cost-Effective physical examination, you performed a rectal examina- Strategies tion, which showed good rectal tone and no evidence of obstruction. You then performed a pelvic examination (with a chaperone present), and it showed vesicular le- • In patients with no comorbidities where BPH is sions suggestive of herpes. Adequate pain control was the likely etiology of AUR, the only laboratory achieved. Ultrasound showed a fully distended bladder. study necessary is a urinalysis. You gave the patient acetaminophen, IV acyclovir, and IV • Asymptomatic bacteriuria in patients with fluids, and you started cardiorespiratory monitoring. You chronic indwelling catheters is common and performed complete bladder decompression using a 16F does not need further intervention or antibiotic Foley and sent the urine for urinalysis and culture. The treatment. urinalysis returned positive for white blood cells, so you • Utilize ultrasound for Foley, Coude, and supra- gave her IV ceftriaxone and admitted her to medicine for pubic catheter placement to avoid costly compli- IV antibiotics, IV fluids, and antivirals. cations. • Remember that guidelines state that men with mild lower urinary tract symptoms can be fol- lowed expectantly with watchful waiting rather than rushing to surgical intervention. • Urgent attention to bladder decompression of extremely uncomfortable patients may result in less need for hospital resources, such as pain medications. • Using ultrasound to diagnose AUR in a patient with abdominal pain may obviate the need for more expensive diagnostic testing (such as CT scan).

January 2014 • www.ebmedicine.net 17 Emergency Medicine Practice © 2014 Risk Management Pitfalls For Acute Urinary Retention

1. “My female patient was having difficulty 7. “I did a CT scan on a patient with abdominal urinating, so I assumed that it was a UTI and pain. It showed a markedly full, distended omitted the pelvic exam.” bladder. Maybe I should have done an ultra- A thorough pelvic examination is important sound first.” in ruling out uterine prolapse or other organ A thorough history and physical examination obstruction as a cause of AUR in women. is needed to differentiate AUR as a cause of abdominal distension and pain, and bedside 2. “I treated this patient in the ED for AUR and ultrasound may be used to confirm the diagnosis removed his Foley prior to his discharge, but instead of other costly diagnostic modalities. he is back again today!” Up to 70% of men with AUR due to BPH will 8. “The patient seemed reliable, and I assumed have recurrence if the bladder is drained only he would follow up at the urology clinic. Little during the ED visit and the catheter is removed did I know that they didn’t have any appoint- prior to discharge. ments for 3 months!” Remember the importance of prompt 3. “I went to place a suprapubic catheter in my urological follow-up and the complications of patient and aspirated air.” chronic catheter usage. It is essential to ensure Remember the potential bad outcomes involved that the patient does actually have follow-up with a misplaced suprapubic catheter and prior to discharge. the importance of using ultrasound during placement and for confirmation of successful 9. “I removed the fluid from the Foley balloon, Foley, Coude, and suprapubic catheter insertion. and now it will not come out.” There is a risk of balloon cuffing when fluid is 4. “The nurse kept telling me that the patient had removed too quickly from the catheter balloon. severe low back pain. It was busy in the ED, so Consider instilling 0.5 to 1 mL of water into the I gave him 2 Percocets and 4 mg of IV mor- balloon to smooth the already-formed cuffs. phine before I assessed him. It turned out all that he needed was bladder decompression.” 10. “I sent home an elderly patient with tamsulo- Urgent bladder decompression is the definitive sin and an indwelling catheter, but she came treatment for AUR, and it treats pain and saves back after passing out at home.” money on unnecessary testing. Also, treating the Though prescribing alpha blockers is patient’s pain acts to improve his ED experience. recommended, orthostatic hypotension is a common side effect in patients taking these 5. “The resuscitation was busy, and I couldn’t medications. Adequate instruction on the side find saline, so I injected air into the Foley bal- effects of all medications prescribed must be loon. Now it doesn’t work.” given to the patient and family. Tamsulosin Injecting air into the Foley balloon may cause may be taken at night to reduce the impact of it to sit inappropriately within the bladder, side effects. interfering with its function.

6. “I placed a Foley in an elderly gentlemen with AUR and discharged him home. Now he has returned with paraphimosis.” Remember to reduce the foreskin in uncircumcised patients, as it may cause paraphimosis.

Emergency Medicine Practice © 2014 18 www.ebmedicine.net • January 2014 References tatic hyperplasia. Finasteride Long-Term Efficacy and Safety Study Group. N Engl J Med. 1998;338(9):557-563. (Prospec- tive randomized controlled; 3040 patients) Evidence-based medicine requires a critical ap- 16. Selius BA, Subedi R. Urinary retention in adults: diagnosis praisal of the literature based upon study methodol- and initial management. Am Fam Physician. 2008;77(5):643- ogy and number of subjects. Not all references are 650. (Review) equally robust. The findings of a large, prospective, 17. Fitzpatrick JM, Kirby RS. Management of acute urinary retention. BJU Int. 2006;97 Suppl 2:16-20. (Review) random­ized, and blinded trial should carry more 18. Sasaki K, Yoshimura N, Chancellor MB. Implications of dia- weight than a case report. betes mellitus in urology. Urol Clin North Am. 2003;30(1):1- To help the reader judge the strength of each 12. (Review) reference, pertinent information about the study 19. Tintinalli JE. Acute urinary retention as a presenting sign of will be included in bold type following the ref­ spinal cord compression. Ann Emerg Med. 1986;15(10):1235- 1237. (Case report; 3 patients) erence, where available. In addition, the most infor- 20. Hemrika DJ, Schutte MF, Bleker OP. Elsberg syndrome: a mative references cited in this paper, as determined neurologic basis for acute urinary retention in patients with by the authors, will be noted by an asterisk (*) next genital herpes. Obstet Gynecol. 1986;68(3 Suppl):37S-39S. to the number of the reference. (Case report; 3 patients) 21. Murray K, Massey A, Feneley RC. Acute urinary retention--a urodynamic assessment. Br J Urol. 1984;56(5):468-473. (Pro- 1.* Vilke GM, Ufberg JW, Harrigan RA, et al. Evaluation spective; 30 patients) and treatment of acute urinary retention. J Emerg Med. 22.* Nyman MA, Schwenk NM, Silverstein MD. Management of 2008;35(2):193-198. 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Lapides J, Diokno AC, Silber SJ, et al. Clean, intermittent methods of epidural analgesia. Eur J Obstet Gynecol Reprod self-catheterization in the treatment of urinary tract disease. J Biol. 1997;71(1):31-34. (Prospective study; 1000 patients) Urol. 1972;107(3):458-461. (Prospective; 14 patients) 26. Bourn MK, Bourn SS. Genitourinary emergencies: a prehos- 6. Kaplan SA. AUA guidelines and their impact on the man- pital perspective. Emerg Med Clin North Am. 1988;6(3):379- agement of BPH: an update. Rev Urol. 2004;6 Suppl 9:S46- 389. (Review) S52. (Literature review) 27. Sand M, Bechara FG, Sand D, et al. Surgical and medical 7. Armitage JN, Sibanda N, Cathcart PJ, et al. Mortality in men emergencies on board European aircraft: a retrospective admitted to hospital with acute urinary retention: database study of 10,189 cases. Crit Care. 2009;13(1):R3. (Retrospec- analysis. BMJ. 2007;335(7631):1199-1202. (Systematic review) tive study; analysis of 10,189 inflight medical and surgical 8.* Jacobsen SJ, Jacobson DJ, Girman CJ, et al. Natural history emergencies) of prostatism: risk factors for acute urinary retention. J Urol. 28. United States Federal Aviation Administration. Appendix 1997;158(2):481-487. (Retrospective cohort study; 2115 pa- A to Part 121: first aid kits and emergency medical kits. tients) Electronic Code of Federal Regulations. 2013. Available at: 9. Cathcart P, van der Meulen J, Armitage J, et al. Incidence of http://www.ecfr.gov/cgi-bin/text-idx?SID=2e564084c2e0d primary and recurrent acute urinary retention between 1998 8aa83cc3569277c9b1a&node=14:3.0.1.1.7.30.3.2.8&rgn=div9. and 2003 in England. J Urol. 2006;176(1):200-204. (Database Accessed November 20, 2013. (Government regulations) review) 29. United States Federal Aviation Administration. Subpart M: 10. Klarskov P, Andersen JT, Asmussen CF, et al. Acute urinary airman and crewmember requirements. Electronic Code of retention in women: a prospective study of 18 consecutive Federal Regulations. 2013. Available at: http://www.ecfr. cases. Scand J Urol Nephrol. 1987;21(1):29-31. (Prospective; 18 gov/cgi-bin/text-idx?SID=2e564084c2e0d8aa83cc3569277c9b patients) 1a&node=14:3.0.1.1.7.13&rgn=div6. Accessed November 20, 11. Afonso AS, Verhamme KM, Stricker BH, et al. Inhaled 2013. (Government regulations) anticholinergic drugs and risk of acute urinary retention. 30. Editorial staff. Enhanced emergency medical kits increase BJU Int. 2011;107(8):1265-1272. (Nested case-control cohort in-flight care options.Cabin Crew Safety. 2001;36(6):1-6. study; 22,579 patients) 31. Jones JA, Kirkpatrick AW, Hamilton DR, et al. Percutane- 12. Meigs JB, Barry MJ, Giovannucci E, et al. Incidence rates and ous bladder catheterization in microgravity. Can J Urol. risk factors for acute urinary retention: the health profession- 2007;14(2):3493-3498. (Porcine model study) als followup study. J Urol. 1999;162(2):376-382. (Prospective 32. Roehrborn CG, Girman CJ, Rhodes T, et al. Correlation cohort study; 41,276 men) between prostate size estimated by digital rectal examina- 13. Bernat JL, Greenberg ER, Barrett J. Suspected epidural tion and measured by transrectal ultrasound. Urology. compression of the spinal cord and cauda equina by meta- 1997;49(4):548-557. (Meta-analysis) static carcinoma. Clinical diagnosis and survival. Cancer. 33.* Shah K, Teng J, Shah H, et al. Can bedside ultrasound assist 1983;51(10):1953-1957. (Review; 133 patients) in determining whether serum creatinine is elevated in cases 14. Wein A. Pathophysiology and classification of lower urinary of acute urinary retention? J Emerg Med. 2010;39(2):198-203. tract dysfunction: overview. In: Wein A, Kavoussi L, Novick (Prospective observational study; 96 patients) A, et al, eds. Campbell-Walsh Urology. 10th ed. Philadelphia: 34. Fontanarosa PB, Roush WR. Acute urinary retention. Emerg Saunders Elsevier; 2011:1834-1846. (Textbook) Med Clin North Am. 1988;6(3):419-437. (Review) 15. McConnell JD, Bruskewitz R, Walsh P, et al. The effect of 35. Emberton M, Anson K. Acute urinary retention in men: an finasteride on the risk of acute urinary retention and the age-old problem. BMJ. 1999;318(7188):921-925. (Systematic need for surgical treatment among men with benign pros-

January 2014 • www.ebmedicine.net 19 Emergency Medicine Practice © 2014 review) agement. Expert Opin Pharmacother. 2010;11(8):1255-1261. 36. Meares EM, Stamey TA. Bacteriologic localization patterns in (Review) bacterial prostatitis and urethritis. Invest Urol. 1968;5(5):492- 53. Mustonen S, Ala-Houhala IO, Vehkalahti P, et al. Kidney ul- 518. (Review) trasound and Doppler ultrasound findings during and after 37. Magri V, Wagenlehner FM, Montanari E, et al. Semen analy- acute urinary retention. Eur J Ultrasound. 2001;12(3):189-196. sis in chronic bacterial prostatitis: diagnostic and therapeutic (Prospective study; 25 patients) implications. Asian J Androl. 2009;11(4):461-477. (Retrospec- 54. Breum L, Klarskov P, Munck LK, et al. Significance of acute tive study; 1100 patients) urinary retention due to intravesical obstruction. Scand J Urol 38. Curtis LA, Dolan TS, Cespedes RD. Acute urinary reten- Nephrol. 1982;16(1):21-24. (Prospective study; 107 patients) tion and urinary incontinence. Emerg Med Clin North Am. 55.* Taube M, Gajraj H. Trial without catheter following acute 2001;19(3):591-619. (Literature review) retention of urine. Br J Urol. 1989;63(2):180-182. (Prospective 39. Aguilera PA, Choi T, Durham BA. Ultrasound-guided study; 60 patients) catheter placement in the emergency 56. Desgrandchamps F, De La Taille A, Doublet JD. The man- department. J Emerg Med. 2004;26(3):319-321. (Prospective agement of acute urinary retention in France: a cross-section- case series; 17 patients) al survey in 2618 men with benign prostatic hyperplasia. BJU 40. McPhail MJ, Abu-Hilal M, Johnson CD. A meta-analysis Int. 2006;97(4):727-733. (Prospective cross-sectional survey; comparing suprapubic and transurethral catheterization 2618 patients) for bladder drainage after abdominal surgery. Br J Surg. 57. Fitzpatrick JM, Desgrandchamps F, Adjali K, et al. Man- 2006;93(9):1038-1044. (Meta-analysis) agement of acute urinary retention: a worldwide survey 41. Brosnahan J, Jull A, Tracy C. Types of urethral catheters for of 6074 men with benign prostatic hyperplasia. BJU Int. management of short-term voiding problems in hospital- 2012;109(1):88-95. (Prospective cross-sectional survey; 6074 ised adults. Cochrane Database Syst Rev. 2004(1):CD004013. patients) (Cochrane review) 58. McNeill SA, Hargreave TB. Alfuzosin once daily facilitates 42. Niel-Weise BS, van den Broek PJ. Urinary catheter policies return to voiding in patients in acute urinary retention. J for short-term bladder drainage in adults. Cochrane Database Urol. 2004;171(6 Pt 1):2316-2320. (Prospective study; 360 Syst Rev. 2005(3):CD004203. (Cochrane review) patients) 43. Allardice JT, Standfield NJ, Wyatt AP. Acute urinary reten- 59. Lucas MG, Stephenson TP, Nargund V. Tamsulosin in the tion: which catheter? Ann R Coll Surg Engl. 1988;70(6):366- management of patients in acute urinary retention from 368. (Prospective study; 50 patients) benign prostatic hyperplasia. BJU Int. 2005;95(3):354-357. 44. AUA guideline on management of benign prostatic hyper- (Prospective multicenter study; 149 men) plasia (2003). Chapter 1: diagnosis and treatment recommen- 60. Barnes KE, Malone-Lee J. Long-term catheter management: dations. J Urol. 2003;170(2 Pt 1):530-547. (Guideline review) minimizing the problem of premature replacement due to 45. Kirby RS, Roehrborn C, Boyle P, et al. Efficacy and tolerabil- balloon deflation. J Adv Nurs. 1986;11(3):303-307. (Review of ity of doxazosin and finasteride, alone or in combination, in evidence-based practice guidelines) treatment of symptomatic benign prostatic hyperplasia: the 61. Cochran S. Care of the indwelling urinary catheter: is Prospective European Doxazosin and Combination Therapy it evidence based? J Wound Ostomy Continence Nurs. (PREDICT) trial. Urology. 2003;61(1):119-126. (Prospective 2007;34(3):282-288. (Review article of practice guidelines) double-blind placebo-controlled trial; 1095 patients) 62. Smith JM. Indwelling catheter management: from habit- 46. Roehrborn CG, Bruskewitz R, Nickel JC, et al. Sustained based to evidence-based practice. Ostomy Wound Manage. decrease in incidence of acute urinary retention and surgery 2003;49(12):34-45. (Review) with finasteride for 6 years in men with benign prostatic 63. Gonzalgo ML, Walsh PC. Balloon cuffing and management hyperplasia. J Urol. 2004;171(3):1194-1198. (Retrospective of the entrapped Foley catheter. Urology. 2003;61(4):825-827. analysis of PLESS study) 64. Shapiro AJ, Soderdahl DW, Stack RS, et al. Managing 47. O’Leary MP, Roehrborn C, Andriole G, et al. Improvements the nondeflating uretral catheter. J Am Board Fam Pract. in benign prostatic hyperplasia-specific quality of life with 2000;13(2):116-119. (Literature review) dutasteride, the novel dual 5-alpha-reductase inhibitor. BJU 65. Hollingsworth M, Quiroz F, Guralnick ML. The manage- Int. 2003;92(3):262-266. (Prospective randomized controlled ment of retained Foley catheters. Can J Urol. 2004;11(1):2163- studies; 4325 patients) 2166. (Review of 13 cases) 48. Nickel JC, Gilling P, Tammela TL, et al. Comparison of 66. Roehrborn CG. Acute urinary retention: risks and manage- dutasteride and finasteride for treating benign prostatic ment. Rev Urol. 2005;7 Suppl 4:S31-S41. (Review) hyperplasia: the Enlarged Prostate International Comparator 67. Modi P, Pleat J, Cheetham P, et al. A 23-year review of the Study (EPICS). BJU Int. 2011;108(3):388-394. (Review) management of acute retention of urine: progressing or 49.* McConnell JD, Roehrborn CG, Bautista OM, et al. The regressing? Ann R Coll Surg Engl. 2000;82(5):333-335. (Retro- long-term effect of doxazosin, finasteride, and combination spective review; 1257 patients) therapy on the clinical progression of benign prostatic hy- 68. Drinka PJ. Complications of chronic indwelling urinary perplasia. N Engl J Med. 2003;349(25):2387-2398. (Prospective catheters. J Am Med Dir Assoc. 2006;7(6):388-392. (Review) double-blind, placebo-controlled trial; 3047 men) 69. Kunin CM, Douthitt S, Dancing J, et al. The association be- 50. Roehrborn CG, Barkin J, Siami P, et al. Clinical outcomes tween the use of urinary catheters and morbidity and mortal- after combined therapy with dutasteride plus tamsulosin or ity among elderly patients in nursing homes. Am J Epidemiol. either monotherapy in men with benign prostatic hyper- 1992;135(3):291-301. (Prospective study; 1540 patients) plasia (BPH) by baseline characteristics: 4-year results from the randomized, double-blind Combination of Avodart and Tamsulosin (CombAT) trial. BJU Int. 2011;107(6):946-954. (Prospective randomized controlled trial; 4844 patients) 51. Nicolle LE, Bradley S, Colgan R, et al. Infectious Diseases Society of America guidelines for the diagnosis and treat- ment of asymptomatic bacteriuria in adults. 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Emergency Medicine Practice © 2014 20 www.ebmedicine.net • January 2014 CME Questions 5. In treating spontaneous AUR in the ED after Foley insertion, one should do which of the following? Take This Test Online! a. Decompress the entire bladder and leave the Foley in. Current subscribers receive CME credit absolute- b. Decompress the entire bladder and remove ly free by completing the following test. Each TM the Foley. issue includes 4 AMA PRA Category 1 Credits , 4 c. Only partially decompress the bladder and ACEP Category 1 credits,Take This 4 TAAFPest Online! Prescribed leave the Foley in. credits, and 4 AOA Category 2A or 2B credits. d. Only partially decompress the bladder and Monthly online testing is now available for remove the Foley. current and archived issues. To receive your free CME credits for this issue, scan the QR code 6. Which of the following are contraindications to below with your smartphone or visit Foley placement? www.ebmedicine.net/E0114. a. Postoperative urological patient with known bladder neck or prostate surgery b. Known impassible Foley insertion c. Radiographic evidence of bladder trauma d. Scrotal/perineal hematoma e. All of the above

7. Which of the following catheters is character- ized by having a curved tip, balloon inflation 1. What is the most common cause of AUR in lumen, and draining lumen, and is commonly women? used for continuous catheterization? a. Medications a. Single-lumen Foley b. Bladder masses and pelvic prolapse b. Double-lumen Foley c. Trauma c. Triple-lumen Foley d. UTI d. Coude catheter

2. Relaxation of the detrusor muscle to hold urine 8. Which of the following is an absolute contrain- involves which of the following? dication for suprapubic catheter placement? a. Parasympathetic inhibition of the detrusor a. Pregnancy muscle b. Uncontrolled coagulopathy b. Parasympathetic stimulation of the detrusor c. Pediatric cases muscle d. Prior abdominal or pelvic surgery c. Beta-adrenergic inhibition of the detrusor muscle 9. Which of the following is not an indication for d. Alpha-adrenergic inhibition of the detrusor urology consult? muscle a. Genitourinary trauma b. Failed Foley and Coude catheter placement 3. In addressing AUR in special patients, such as c. Uncontrolled hematuria the elderly, one must keep in mind which of d. Transient hypotension after bladder the following: decompression a. Vital signs may not be actual predictors of pathology 10. Which medication improves the likelihood of b. Patients in this category may be unable to spontaneous voiding after catheter removal? complain of discomfort a. Cyclobenzaprine c. Obtaining collateral information may be b. Finasteride helpful in determining history of present c. Tamsulosin illness d. Ciprofloxacin d. All of the above

4. Which part of the physical examination is es- sential in women presenting with AUR? a. Rectal exam b. Genital/pelvic exam c. Both a and b d. Neither a nor b

January 2014 • www.ebmedicine.net 21 Emergency Medicine Practice © 2014 Get 4 Hours Stroke CME Credit From This Month in EM Practice The July and August 2013 Issues Of Guidelines Update: Current EM Practice Guidelines Update Guidelines For The Evaluation And Management Of Heart Failure The January/February 2014 issue of EM Practice Guidelines Update reviews 2 recently updated guidelines on the evaluation and management of heart failure: the European Society of Cardiology guideline, a 2012 update of their 2008 publication; and the joint American College of Cardiology The July and August issues of our online journal Foundation/American Heart Association supplement, EM Practice Guidelines Update, are guideline, a 2013 update of their 2009 devoted to stroke topics, and each offers 2 hours publication. Trevor Lewis, MD; Deb Diercks, of Stroke CME credit. All subscribers to Emergen- MD; and Sigrid Hahn, MD have reviewed cy Medicine Practice automatically receive free these 2 updated guidelines and offer subscriptions to EM Practice Guidelines Update; summary and comment on what emergency to access the articles, simply log in to your clinicians need to know about treating www.ebmedicine.net account (or give us a call patients with heart failure in the ED. and we’ll help you get your account set up). Although heart failure is a , The July issue reviews the 2009 guideline on the emergency clinician must be well-versed transient ischemic attack (TIA) and the revised in acute and chronic treatments and novel American Heart Association/American Stroke concepts for early detection. Association (AHA/ASA) “tissue-based” diagnosis of TIA. Jonathan Edlow, MD, of Harvard Medical Some of the recommendations discussed in School, offers a guest editorial on the evolu- this issue include: tion of effective emergency care options for TIA patients, and Editor-in-Chief Sigrid Hahn, • Chest x-ray, natriuretic peptide MD reviews and comments on portions of the measurements, and ECG in the ED offer guideline relevant to emergency clinicians. Read diagnostic options. the issue online at: www.ebmedicine.net/TIA. The August 2013 issue reviews 2 different • Prompt treatment in the ED with IV guidelines published in 2013 on acute ischemic diuretics has been shown to reduce stroke and the use of intravenous t-PA (tissue morbidity in hemodynamically stable plasminogen activator) from: (1) the American patients. College of Emergency Physicians jointly with the American Academy of Neurology, and (2) • Vasodilators may be used as an adjunct the AHA/ASA. Christopher Hopkins, MD of the to diuretics to reduce dyspnea. University of Florida College of Medicine-Jackson- ville, the guest editor, provides an assessment of This online issue offers 2 hours of CME credit. these controversial new guidelines, which have Be sure to log on to www.ebmedicine.net been 8 years in development. Read this issue to download your free subscription to online at: www.ebmedicine.net/Stroke. EM Practice Guidelines Update. Not sure how to access your account? Call us at 1-800-249-5770 and we'll be glad to help you get started.

Emergency Medicine Practice © 2014 22 www.ebmedicine.net • January 2014 Coming Soon In Emergency Medicine Practice

Cardiovascular Toxicity: Risk Stratification And Clinical Management Of Digoxin, Decision-Making For Calcium-Channel Blocker, And Syncope In The Emergency Beta Blocker Toxicity Department

AUTHORS: AUTHORS: WESLEY PALATNICK, MD, FRCPC SUZANNE Y.G. PEETERS, MD Professor and Program Director, Emergency Medicine Emergency Medicine Residency Director, Haga Residency, University of Manitoba; Attending Hospital, The Hague, The Netherlands Physician, Department of Emergency Medicine, J. STEPHEN HUFF, MD, FACEP Health Sciences Centre, Winnipeg, Manitoba, Canada Associate Professor of Emergency Medicine and TOMISLAV JELIC, MD Neurology, University of Virginia, Charlottesville, VA Department of Emergency Medicine, University of AMBER E. HOEK, MD Manitoba, Winnipeg, Canada Emergency Medicine Residency Director, Haga The prevalence of cardiovascular disease is Hospital, The Hague, The Netherlands increasing due to the aging population, and SUSAN M. MOLLINK, MD cardiovascular medications, especially beta blockers Emergency Medicine Residency, Haga Hospital, The and calcium-channel blockers, are now some of the Hague, The Netherlands most-prescribed therapeutic agents on the market. As a result of this growing use and availability, there Accounting for 1% to 3% of all emergency department has been a rise in the numbers of toxic exposures. visits, syncope is defined as a transient loss of The 2011 annual report of the American Association consciousness due to transient global cerebral of Poison Control Centers found that cardiovascular hypoperfusion, with rapid onset and spontaneous and medications accounted for 102,766 exposures, which complete recovery. Although syncope is a symptom was 3.74% of all exposures reported, and nearly 11% with a wide range of possible underlying causes, of the fatalities. the most effective diagnostic tools in evaluating a Identifying patients exhibiting toxic effects of patient with syncope are the history and physical these agents and their appropriate management examination. Studies show that if a nonstructured may be difficult. With the advent of newer evaluation is performed, the cause of syncope will be treatment modalities and controversies in others, unidentified in 50% of patients, resulting in high costs management can be complex. Standard Advanced and low diagnostic yield; however, if standardized Cardiovascular Life Support (ACLS) protocols used for clinical evaluations are used, the diagnostic yield the resuscitation of patients in cardiac arrest may increases up to 76%. Several decision rules for syncope be insufficient due to the physiologic changes that have been developed, and although none are sensitive occur with poisoning with these agents, and often, and specific enough to use in the ED setting, they give specific and specialized treatments are necessary. a good overview of existing risk factors that predict This issue of Emergency Medicine Practice presents short-term adverse events. This issue of Emergency the current evidence on best-practice diagnosis Medicine Practice presents the best available evidence and management of beta blocker, calcium-channel for diagnosis and risk stratification for syncope and blocker, and digoxin toxicity. provides guidance in differentiating patients who can be safely discharged and those who need to be hospitalized.

January 2014 • www.ebmedicine.net 23 Emergency Medicine Practice © 2014 Physician CME Information Date of Original Release: January 1, 2014. Date of most recent review: December 10, 2013. Termination date: January 1, 2017. Accreditation: EB Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This activity has been planned and implemented in accordance with the Essential Areas and Policies of the ACCME. Credit Designation: EB Medicine designates this enduring material for a maximum of 4 AMA PRA Category I Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity. ACEP Accreditation: Emergency Medicine Practice is approved by the American College of Emergency Physicians for 48 hours of ACEP Category I credit per annual subscription. 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Emergency Medicine Practice © 2014 24 www.ebmedicine.net • January 2014