Patients With Substance Use Disorders 15 Mladen Nisavic, M.D. Shamim H. Nejad, M.D. OVERVIEW readiness for recovery), identification of outpatient addiction resources, and use of medications to reduce craving and to Without a doubt, substance use disorders (SUDs) present maintain recovery. The chronic, relapsing, nature of sub- one of the gravest difficulties currently facing the United stance use may inspire resignation and hopelessness in States healthcare system. Over the past two decades, the consulting clinicians, leading to a misperception that the number of patients treated for substance use-related problems consultation is unnecessary, or even futile. Because most in the United States has grown steadily, and over the past clinicians fail to appreciate that the relapse rate for other 5 years it has reached epidemic proportions. Data from the common chronic medical disorders (e.g., diabetes, hyperten- Centers for Disease Control and Prevention (CDC) indicate sion, asthma) exceeds that for SUDs, they do not treat that in the 10 years between 2004 and 2014, the mortality substance abuse patients with comparable therapeutic dili- rates attributed to drug overdoses increased by 137%, gence.3 The Massachusetts General Hospital (MGH) has including a staggering 200% increase in the rate of overdose dedicated considerable effort and resources to adequately deaths attributed to opioids. The increased mortality rates address the substance use epidemic within our local com- were independent of sex, age group, or ethnicity, and were munities, starting with a hospital-wide effort to ensure that evident across the country. In fact, the CDC estimates that problems related to substance use are addressed with the nearly half a million persons in the United States died from same degree of compassion and persistence directed at other drug overdoses between 2000 and 2014, and that drug-related common relapsing medical disorders. Medical and surgical fatalities were one and a half times higher than deaths from hospitalizations often provide extended periods during which motor vehicle crashes in 2014.1 Up to 80% of all drug-related patients are separated from their substance use, and thus fatalities appear to be unintentional, with 13% attributed hospitalization may present a unique opportunity to engage to suicide, and the remainder classified as undetermined. the patient in meaningful interventions. The increase in drug use has also led to increased utiliza- tion of healthcare services. The Drug Abuse Warning Network (DAWN) and the Substance Abuse and Mental Health Service Administration (SAMHSA) estimate that over 5 million Emergency Department (ED) visits in 2011 CASE 1 were related to drug use—a 100% increase over their 2004 Mr. B, a 36-year-old homeless man with a history of sub- data. Of these, nearly 2.5 million ED visits were attributed stance use and abuse (benzodiazepines, opiates, and to medical emergencies related to drug abuse. stimulants), was admitted to the vascular surgery service Clinical presentations in this domain are also becoming with ischemia to his right hand and forearm. The injury more complex. Of the 2.5 million ED visits identified by was sustained when he relapsed on “heroin” (after 2 months DAWN/SAMHSA in 2011, nearly one-half involved of recovery), and became obtunded with a protracted complications related to use of prescription medications, period of immobility. An initial urine toxicology screen with the remainder being attributed to use of non-prescription was positive for benzodiazepines and opioids, with further illicit drugs. While the use of opioids, marijuana, and cocaine toxicology testing that confirmed the presence of clonaz- are seen most commonly, more than 50% of the patients epam, methadone, and fentanyl. Psychiatric consultation present with co-ingestion of multiple substances, and there was requested to assist with pain management and to has been an increase in use of CNS stimulants, “club drugs,” provide assistance with addiction recovery treatment and hallucinogens.2 referral and resources. Successful treatment of this expanding group of patients On interview, Mr. B was alert, oriented, lucid, and requires that clinicians improve their management skills for forthcoming. He reported surprise, and then frank fear, SUDs and their sequelae. This involves timely and correct that he “ended up this way—after all I only used once.” He diagnosis of the substance use problem, recognition of also appeared surprised that the toxicology screen revealed key symptoms associated with intoxication or acute evidence of fentanyl and benzodiazepines, as he was discontinuation/withdrawal, and appropriate initial manage- “certain” he used heroin. He complained of pain, despite ment and treatment. It also involves meaningful engagement being on his methadone maintenance (75 mg/day), and (including motivational enhancement techniques to assess 149 Downloaded for Anonymous User (n/a) at Uniformed Services Univ of the Health Sciences from ClinicalKey.com by Elsevier on September 16, 2018. For personal use only. No other uses without permission. Copyright ©2018. Elsevier Inc. All rights reserved. 150 Chapter 15 Patients With Substance Use Disorders neutralization by the acidic milieu of the stomach). More expressed concern that his pain would be under-treated commonly, cocaine is injected, insufflated or inhaled (as because of his history of substance use. His mood was “crack”) as the latter methods greatly increase the bioavail- appropriate to the clinical context: there was no evidence ability of the drug. of depression. Following initial stabilization, Mr. B underwent amputa- Pharmacology and Mechanism of Action tion of his right forearm and hand. During the perioperative Cocaine increases the monoamine neurotransmitter activ- period, he received a combination of long-acting opioids ity in the central nervous system (CNS) by blocking the for basal analgesic control, as well as short-acting opioids pre-synaptic re-uptake transporters for dopamine, norepi- for breakthrough pain. His methadone dose was increased nephrine, and serotonin. Given the potent effects of cocaine to 90 mg/day, and was split into three-times-a-day dosing on dopamine’s availability within the CNS, much of the to optimize pain management. His short-acting opioids drug’s stimulant and addictive effects have been ascribed (intravenous [IV], then oral hydromorphone) were tapered to its effects on the corticomesolimbic dopamine reward gradually over 2 weeks while he remained in the inpatient circuits.5,6 In addition to these effects, cocaine also acts by setting. blocking voltage-gated sodium ion channels, an action that With improved pain control, Mr. B more readily engaged accounts for its effect as a local anesthetic and contributes in readiness work via motivational interviewing and he to its cardiac toxicity. accepted addiction recovery services. He identified The route of administration greatly influences the methadone maintenance as a key element to his recovery bioavailability of the drug, including its onset and duration and noted no cravings on the higher dose of his medication. of intoxication. Smoking (i.e., inhalation) and IV use gener- He found inspiration in his survival, and despite grieving ally lead to near instantaneous (seconds to minutes) effects, the loss of his limb, expressed a strong readiness to maintain and most patients note that the drug’s effects wear off within recovery. He worked closely with the consultation team 30 minutes. Intranasal administration results in slower onset to identify triggers for relapse and secured a safe disposition of symptoms (within 30 minutes) and the effects of the drug plan. By the end of his 2-week hospital stay, Mr. B held are similarly extended to up to 1 hour. regular meetings with Narcotics Anonymous (NA) peers Cocaine is commonly co-administered with alcohol, in the hospital. He maintained continuous contact with which leads to the formation of cocaethylene, a compound his methadone provider and allowed the consultation team with stimulant effects similar to that of cocaine, albeit with to share their impressions with the clinic. a longer half-life. This compound has also been noted to Mr. B was discharged to his parents’ home, with a plan to carry greater cardiac toxicity compared with cocaine alone. follow-up with his methadone clinic and NA. He expressed Cocaine is extensively metabolized by the liver, and its (appropriate) anxiety on discharge, as he readily admitted metabolites are eliminated in the urine, most commonly as that the road ahead of him would be challenging, but also benzoylecgonine. This metabolite (rather than the parent noted hope and readiness to battle his addiction. compound) is detected by urine drug tests for cocaine; it can be detected as early as 4 hours after intake, and may remain detectable for up to 1 week after cocaine is used. There are STIMULANTS no common false positives for urine cocaine screen. Cocaine Cocaine intoxication is associated with potent stimulant effects, including increased energy and alertness, bright (to Cocaine is a tropane alkaloid naturally found in leaves of frankly euphoric) affect, insomnia, as well as anorexia. Similar the Erythroxylum coca plant, a bush native to the Andes to other stimulants, cocaine is associated with an intensely Mountains region of South America. To this day, leaves of pleasurable state and is commonly used to potentiate sexual the plant continue to be used by the indigenous people activity. With