1. 
   

   Is this patient opioid dependent?

   
   
2. 
   

   Is this patient in opioid withdrawal?

   
   
3. 
   

   How should opioid withdrawal be managed?

   
   
4. 
   

   How can pain be managed in an opioid-dependent patient?

   
   
5. 
   

   What discharge planning should take place for opioid-dependent patients?

Opioid misuse, primarily in the form of heroin, has been a longstanding problem in the urban United States. Opioids are now among the most commonly prescribed medications in the U.S. As a result, problems related to opioids are frequently seen in hospitalized patients. The admitting diagnosis may be related directly to opioids, or opioid related problems may complicate the hospital course. Regardless of the source or severity of the problem, all Hospital Medicine specialists must understand the evaluation and management of patients who are regularly taking opioids.

The term opiate traditionally refers to those drugs that are naturally derived from the poppy plant, and opioid generally refers to synthetic and semisynthetic drugs that are structurally similar to morphine, the prototypic opiate. In this chapter, the term opioid is preferentially used to encompass the broad category of morphine-like analgesics (Table 234-1).

The clinical management of opioid-related problems requires the use of both clear terminology and clinical definitions. Tolerance, dependence, and addiction are sometimes used inappropriately due to lack of understanding or lack of clinical clarity. In this chapter, the terms addiction and opioid addiction refer to the pathologic syndrome of opioid dependence with uncontrolled use despite consequences. Hospitalized patients may also present with pseudoaddiction, which is drug-seeking behavior that occurs in response to inadequate treatment of pain.

Opioid use and problems associated with opioid use have increased dramatically in the United States over the last 15 years. Although there is significant regional variation in the types of opioids used and the patterns of use, several trends are worth noting. Epidemiologic surveys from the United States indicate that over 5 million people used opioids for nonmedical purposes in 2007. U.S. data from 2005 indicate there were more than 100,000 new users of heroin that year. Given these trends, it is likely that Hospital Medicine specialists will frequently encounter patients with opioid-related problems.

Heroin

Heroin (diacetylmorphine) is a semisynthetic derivative of morphine that is illicitly available as a crystalline white powder. Heroin can be smoked, injected, or inhaled by nasal insufflation (“snorted”) to produce relaxation and an intense euphoria. Increased abuse in the United States over the last 20 years has been largely linked to greater availability, lower price, and greater purity. Increased drug purity has allowed new users to experience the euphoria of heroin by snorting rather than injecting and is partially responsible for the increase in new heroin users. Among patients entering treatment for heroin use in 2005 in the United States, approximately two-thirds of patients were injecting and one-third were inhaling.

Prescription Analgesics

Opioids are prescribed for the treatment of acute and chronic pain for millions of Americans. Rates of opioid prescribing have increased substantially over the last two decades. Abuse of and dependence on prescription analgesics in the United States have mirrored the increased use of opioids for the treatment of chronic pain. Data from the 2006 Drug Abuse Warning Network show approximately 324,000 emergency room visits involving nonmedical use of pain relievers.

Opioid-using patients may present to the hospital for a drug-related (intoxication, withdrawal) or non-drug-related problem. Fever, dyspnea, and acute pain are common presenting complaints for opioid-using patients. Underlying infection is often the cause of these complaints, particularly among injection drug users (IDUs). Endocarditis, skin and soft tissue infections, bone and joint infections, epidural abscess, and even pneumonia are more common among IDUs than in general medicine patients. When an opioid user is seen, a key part of the evaluation is to determine if the individual is physically dependent on opioids.

Physical Dependence

A clinical diagnosis of physical opioid dependence is generally obtained through history alone, although the exam can provide a definitive diagnosis for the patient in opioid withdrawal. Physical dependence to opioids occurs at varying rates depending on the patient and the opioid (drug, dose, duration). In general, most patients will have some degree of physical tolerance after two weeks of continuous opioid use. In assessing continuous use, the clinician will need to have some understanding of the duration of opioid action and the pattern of use by the patient. Daily use of a short-acting agent may not result in physical dependence if there is significant time when the patient has no drug exposure (ie, a daily dose of hydrocodone at bedtime).

Opioid Addiction

Diagnosing opioid addiction in the hospital setting may be straightforward, as in the patient who is enrolled in a program for addiction treatment, but frequently the diagnosis is more elusive. Patient reasons for withholding information about drug use typically occur due to past experiences with the medical system, fear of clinician prejudice about drug use, as well as fear about legal issues related to drug use. When evaluating a patient for aberrant opioid use, after assessing for tolerance and withdrawal, an initial question such as, “What problems have opioids caused for you?” may provide clues as to specific criteria for opioid addiction (Table 234-2). The use of state-controlled substance registries can be helpful in the evaluation of suspected prescription drug misuse.

Urine Drug Testing

The role of urine drug testing in the diagnosis of opioid addiction is fairly limited. Providers need to be aware of general test characteristics as well as what tests are locally available. Specific (and separate) urine radioimmunoassay screening tests are widely used by hospitals to screen for opiates, oxycodone, meperidine, propoxyphene, and methadone metabolites. When ordering a urine drug screen, providers need to be aware of which tests the hospital routinely performs and which require specific orders. A screening test in which no drugs are detected never rules out opioid addiction, and a “positive” screening test can only be used to support a clinical diagnosis. Definitive testing can be performed with gas chromatography/mass spectroscopy, but such testing is expensive and results are not immediately available.

The opioid withdrawal syndrome is a constellation of findings that includes symptoms of sympathetic hyperactivity (eg, sweating, tremor, tachycardia, anxiety, pupillary dilation). Opioid withdrawal includes both subjective and objective findings and is dramatically influenced by patient characteristics. A more severe withdrawal syndrome may occur with patients who are psychologically addicted to opioids, have a high degree of opioid tolerance, or have significant concomitant pain. With a short-acting opioid such as heroin or hydrocodone, withdrawal symptoms typically begin 6 to 12 hours after the last use and will peak at 24 to 48 hours (Table 234-3). Peak withdrawal symptoms for a long-acting agent, such as methadone, will occur after 72 hours. Patients may report or develop a pattern of withdrawal that does not follow the prototypic syndrome.

Opioid Withdrawal Severity

Many systems have been developed to grade opioid withdrawal. The Clinical Opioid Withdrawal Scale (COWS) is a widely used 11-item instrument that contains both subjective and objective elements (Table 234-4). It is important for clinicians to recognize that mild opioid withdrawal may be purely subjective (eg, anxiety). Patients who describe a constellation of severe subjective withdrawal symptoms (eg, nausea, anxiety, pain, restlessness) without physical withdrawal signs could represent feigned withdrawal or could occur in a patient who is in withdrawal and anxious about developing a more severe withdrawal syndrome. In either case the appropriate clinician response is continued monitoring and reassurance that appropriate treatment will be provided for relief of specific symptoms.