Coding Education Newsletter

Home , External cause, Respiratory acidosis

Issue 12, May 2014

Inside this issue Coding queries & audit discussion cases Coding queries The May 2014 coding queries and audit discussion cases are now available to view on our website: Audit discussion cases http://www.clinicalcoding.health.wa.gov.au/news/

Clinical review: Acidosis Coding queries 1. Fibroepithelial polyp Coding tip: Non-healing wound 2. Cancelled same day chemotherapy 3. High BMI Back to basics: Failure to progress in labour 4. Attempted hanging with no injury 5. Prophylactic IV fluids before CT scan Coder spotlight: Jillian Dunnette 6. Metabolic acidosis in diabetes patient from Royal Perth Hospital 7. Divarification of rectus muscle with redundant

abdominal skin

8. Capsular contracture of breast implant

9. Sepsis with organ failure

Contacts Audit discussion cases 1. Variceal screening in liver cirrhosis patient Coding Education Team website 2. Booked elective caesarean, presenting in labour www.clinicalcoding.health.wa.gov.au 3. Contaminant in blood culture

Editorial queries [email protected]

Clinical review: Causes of respiratory acidosis Examples

Acidosis Lung parenchyma Chronic lung disease, COPD, Adequate pH balance is vital for normal emphysema, bronchitis, bodily functions. The normal arterial blood pneumoconiosis, ARDS, pH range is 7.35 to 7.45. This balance is pneumonia, pneumothorax maintained by a complex interaction of Airway Obstruction, aspiration, asthma intracellular and extracellular chemical mechanisms interacting with the respiratory Central nervous Drugs (anaesthetics, opioids, and renal systems. If there is a disorder of system sedatives), stroke, infection, head any of these mechanisms, acidosis or injury, brain tumours alkalosis may occur. This indicates an Neuromuscular Chest deformities, kyphoscoliosis, underlying disease process affecting these poliomyelitis, myasthenia gravis, mechanisms. The underlying condition muscular dystrophies, chest needs to be identified and treated injuries appropriately. Other Obesity, hypoventilation Acidosis is the process of accumulation of (Longo et al. 2012, 371) acid or depletion of base in the blood and tissues. The pH of the blood is <7.35 (also known as acidaemia). Metabolic acidosis The opposite disorder is Alkalosis, a In metabolic acidosis (also called non- process where there is too much base in respiratory acidosis) the pH is reduced due the blood and tissues. The pH of the blood to an increase in the body’s production of is >7.45 (Albert et al. 2012, 16). acid, a decrease in the renal excretion of There are two types of acidosis – acid, or increase in excretion of bicarbonate respiratory and metabolic. (Albert et al. 2012, 16).

Respiratory acidosis In respiratory acidosis (also called hypercapnic acidosis, carbon dioxide acidosis) the pH is reduced primarily due to an increase in carbon dioxide (CO2) in the blood (hypercapnia). A common cause is Chronic Obstructive Pulmonary Disease (COPD).

Metabolic acidosis (continued) Diagnosis

Causes of metabolic acidosis Symptoms and signs. Examples The symptoms and signs of acidosis Ketoacidosis Diabetes mellitus (DKA), depend on the underlying condition. starvation, alcohol Metabolic acidosis causes deep rapid breathing, “fruity” odour of acetone on the Lactic acidosis Hypoxia (e.g. ischemia of breath (in ketoacidosis), dehydration, bowel), hypoperfusion (e.g. confusion, lethargy, seizures, or coma. shock, sepsis), metabolic Respiratory acidosis is usually associated conditions (e.g. diabetes with shortness of breath. mellitus), Biguanide (Phenformin, Metformin) Investigations toxicity, liver disease, thiamine deficiency, seizures, Investigations include: arterial blood gases rhabdomyolysis, and alcohol (ABG), urinalysis (ketones, pH, and excess (Harris, Nagy and glucose), electrolytes, blood glucose and Vardaxis 2010, 975). renal function (urea and creatinine), full blood picture, toxicology screen, imaging.

Renal failure Acute and/or chronic. The The diagnosis of acidosis is complex. many acids, urea, sulphates, Different metabolic processes may occur phosphates and proteins with simultaneously e.g. the body attempting to acidic activity are not cleared and accumulate in the body. compensate for respiratory acidosis with metabolic alkalosis (Dr N. Hadlow, personal Toxins Salicylates, methanol, ethanol, communication May 28, 2014). formaldehyde, paraldehyde, sulphates, Metformin Treatment Treatment is primarily of the cause e.g. Gastrointestinal Diarrhoea, fistula, stoma, diabetes mellitus, and specific electrolyte bicarbonate loss drugs e.g. cholestyramine bile management. acid diarrhoea Diabetic ketoacidosis and lactic acidosis Renal tubular Defects of parts of the renal represent two of the most serious acute acidosis (RTA) tubule, with reduced excretion complications of diabetes. Patients with of acid. May occur in isolation (also known as from other renal dysfunction diabetes can present with coexisting hyperchloraemic i.e. normal creatinine; or may conditions such as CKD and acidosis) overlap with renal failure hyperkalaemia. These can also produce a (Harris, Nagy and Vardaxis metabolic acidosis. 2010, 1492). References Hyperkalaemia Drug induced e.g. Spironolactone, Trimethoprin, Albert, Daniel, Block Anne Marie, Bruce Beau, Haines ACE-inhibitors, NSAIDS, Duane, McCloskey Laura, Mitchell Richard, Moore Keith, Cyclosporin Petri William and Telser Alvin. eds. 2012 Dorland’s Illustrated Medical Dictionary. 32nd ed. Philadelphia: Other Acid loads in Elsevier Saunders hyperalimentation, expansion Harris, Peter, Nagy Sue and Vardaxis Nicholas. eds. 2010 acidosis in rapid saline Mosby’s Dictionary of Medicine, Nursing & Health infusion, severe dehydration, Professions. 2nd ed. Sydney: Mosby Elsevier inhalant abuse. Longo, Dan, Kasper Dennis, Jameson Larry, Fauci Anthony, Hauser Stephen and Loscalzo Joseph. eds. th (Longo et al. 2012. 365, 368-369, 371) 2012 Harrison’s Principles of Internal Medicine. 18 ed. New York: McGraw Hill Medical

Coding tip: Non-healing Example “Non-healing wound, on a background of wound sarcoma excision with pre-operative “Non-healing” or “delayed healing” of radiotherapy. Radiotherapy has prevented wounds may be caused by infection or wound healing”. dehiscence, in which case these specific T81.8 Other complications of procedures, conditions should be coded. not elsewhere classified In the absence of infection or dehiscence, Y83.8 Other surgical procedures coding of “non-healing” will depend on the Y92.22 Place of occurrence, health service type of wound. For traumatic wounds, the area original wound should be coded e.g. U73.8 Other specified activity laceration. However, in the case of surgical Y84.2 Radiological procedure and wounds, assign T81.8 Other complications radiotherapy as the cause of of procedures, not elsewhere classified by abnormal reaction, or of later following the index pathway: complication, without mention of misadventure at time of procedure Complications (from)(of) Y92.22 Place of occurrence, health service - procedure (surgical or medical care) area -- specified NEC T81.8 U73.8 Other specified activity followed by external cause codes reflecting the original procedure that created the If clearly linked in the documentation, a surgical wound. condition stated to be impeding wound healing may be coded if criteria in point 2 Examples of factors that can impede wound Problems and underlying conditions are healing: met in ACS 0001 Principal diagnosis.

 Diabetes mellitus  Anaemia Reference Daley, Brian. 2014. “Wound care treatment and  Infection management”. Medscape. Accessed May 23, ttp://emedicine.medscape.com/article/194018-  Medication e.g. corticosteroids overview#a0102

 Nutritional problems e.g. vitamin and zinc deficiency  Vascular disease  Radiotherapy (Daley 2014) When a complication of medical care is documented to be a contributing factor impeding wound healing (e.g. adverse drug effect; radiotherapy), external cause codes can be added to demonstrate this, as per the following example.

Back to basics: Failure Coder spotlight to progress in labour This issue we interviewed Jillian Failure to progress (FTP) in labour often Dunnette from Royal Perth requires intervention such as augmentation Hospital… or instrumental delivery. How long have you been coding? FTP itself is not a condition, rather a Almost four years description that the labour is not progressing due to an underlying cause. At which hospital did you commence Coders should always look for your coding career? documentation to determine the cause of FTP. Some causes include: Royal Perth Hospital  Malpresentation of fetus What made you decide to become a  Poor/inadequate contractions clinical coder?  Cephalopelvic disproportion I wanted a career change from nursing When coding FTP, a code for the underlying cause should be assigned. If What do you like most about clinical there is no documentation of the cause, coding? O62.9 Abnormality of forces of labour, Most things – the interesting cases here at unspecified can be assigned following the Royal Perth, the challenge of finding the index pathway: right codes, the constant wonder at the Failure, failed workings of the human body. - to -- progress (in labour) NEC O62.9 What do you like least about clinical coding? (See also Coding Q & A, December 2012) The frustration when I cannot find the right code or do not feel 100% sure I have the right one, and the underlying concern that I may have missed something important. Coders guide to use of Have you recently undertaken coding nursing and allied workshops, conferences, courses health documentation etc? Or plan to in the future? I recently studied the Intermediate Coding A guide has been developed to assist Course run by HIMAA, and passed. I also coders in the use of nursing and allied had 50 records audited and succeeded in health documentation for clinical coding achieving higher than the required 90% purposes. It is now available on our pass mark so have gone up a level in website: coding. I would like to attend a conference http://www.clinicalcoding.health.wa.gov.au/ in an exotic location some day! education/documentation.cfm Separate guides for nursing and allied health professionals have been developed and circulated to WA hospitals, and are also available on our website.

What casemix/specialties do you find Describe the coding service at your most challenging in your current hospital role? There are 18 coders here at Royal Perth. I find that neurological cases can We are located on the lower ground floor in sometimes be difficult. a peaceful, clean and organised environment. We are fortunate to have The casemix at RPH covers multi-trauma, lectures from surgeons and specialists from serious burns, cardiothoracic- transplants, time to time; also ICU nursing staff who and is the state maxillo-facial unit. RPH explained certain procedures to us, which handles approximately 70% of the state’s really helped to visualise what we were plastics cases as well as patients with coding. It seems that clinicians have serious medical illnesses who are gradually come to respect the work of the transferred from country hospitals. Many coder, as the standard of documentation admissions have long-term mechanical has become very detailed and thorough, ventilation and multiple surgeries, which which helps in providing quality coding. makes for complicated coding. The casemix is complex, but provides variety and a challenge to myself and my fellow coders, and the time at work flies.