HEAT AND DRUG STABILITY

The variety of different body matrices that can be analyzed to determine the presence or absence of different psychoactive substances is extensive, ranging from semen to cerumen. There are, however, practical limitations to the extent to which different biological samples can be used, and the mechanism of collection and supervision of samples are critical to the procedure. This focuses on those biological samples that are commonly used for testing within various drug treatment settings, namely, urine, saliva, blood, and hair. Urinalysis is routinely used in hospitalbased services, blood in forensic environments, hair analysis for medicolegal cases, and saliva tests have been used in the prison services and outreach units. Many would advocate that the assessment of psychoactive drug use could reliably be achieved using self-report from the drug user (client). However,the drug rehabilitation are issues around the method of inquiry the context, purpose, interviewer characteristics, etc. that may bias self-report. Circumstances where the drug user sees the self-report to the inquirer about drug use as influential on his own continued treatment or possible loss of privileges are particular examples.
With a focus on alcohol rehab, Allan has recommended that patients presenting with anxiety and alcohol dependence should first be detoxified and reassessed after 6 weeks when only an expected 10% will be found to have persistent symptoms amounting to an anxiety state. The persistent anxiety can then be treated using conventional pharmacological or behavioral methods. She points out that patients may resist such an approach, preferring to deal with their psychological distress before tackling their substance use. People who are dependent on alcohol or other drugs usually succumb to a number of financial, family, health, and relationship problems, and it is not surprising that many will complain of depression; again it is not surprising that 80% or more will recover within a few weeks of abstinence without recourse to antidepressant treatment.

The drug being tested for and the period of time that the clinician wishes to consider influence
the choice of body fluid. Blood and, to a lesser degree, saliva are likely to give the most accurate
measurement of drugs currently active in the system, whereas urine provides a somewhat broader time period, but with less quantitative accuracy. Hair provides a substantially longer time frame. The routine drug testing strategy most widely adopted is to send urine samples to a laboratory for an initial screen to detect psychoactive drugs of interest. Analysis is performed using a semiautomated commercially available immunoassay or thin layer chromatography (TOXILAB) test. Several types of the former test exist and include radioimmunoassay, RIA:Europ/DPC, enzymemediated immunoassay test, Syva:EMIT, and fluorescence polarization immunoassay, FPIA. Recently, several rapid detection devices (near patient test, NPT) for drugs of abuse screening have been marketed in the U.K. Such tests offer a more rapid turnaround of results to aid clinical decision making.
However, all initial drug screen tests are nonspecific and identify only in a nonquantitative fashion the class of drug present, e.g., opiates, amphetamines, or benzodiazepines, etc. Ideally, any positive test result should then be confirmed by a second test working on different physicochemical principles to the screening test. Gas and liquid chromatography with mass spectrometric detection are regarded as the “gold standard” and are favored where legally defensible results are required. It cannot be overemphasized that the confirmation of drug screening test results is essential. For amphetamine-specific immunoassays, the confirmation test provides the opportunity to differentiate legitimate medicines. For instance, pseudoephedrine and phentermine give a positive test result (cross-react) with tests for illicit drugs like amphetamine and methylenedioxymethamphetamine, MDMA. For opiate drugs, initial immunoassay tests for morphine crossreact with codeine, dihydrocodeine, pholcodeine, 6-monoactetylmorphine (6-MAM), morphine glucuronide, and morphine-6-glucuronide. Consequently, if more than one of these substances is present in a urine sample, the test result will relate to the concentration of the sum of all these opiates and their metabolites. In this way an inaccurate picture of the window-of-detection of opiate drugs in urine may be concluded. The clinical benefit of the confirmation test is that it is able to verify the specific substance(s) present. For example, a confirmation test can detect the presence of 6-MAM, the only specific indicator (metabolite) of heroin use .

Management of Drug Abuse

The management of complications from drug abuse demands a variety of skills from airway management to control of seizures and shock. Several reviews have addressed the issues of general resuscitation and toxidromes.
The purpose of Drug rehab is to present a series of management strategies for the emergency physician or other clinical personnel caring for patients with acute complications from drug abuse. Immediate interventions (e.g., resuscitation and stabilization), secondary interventions (e.g., emergency care after the patient is stable), as well as diagnostic workup (e.g., laboratory data, imaging), and disposition of the patient are discussed. This is proposes a variety of treatment approaches based on a review of the pertinent literature and clinical experience. A general treatment approach based on symptom complex (i.e., seizures, coma, hyperthermia) is presented since initial management decisions frequently have to be made without the benefit of a reliable history. This is followed by a brief review of the each particular drug of abuse (i.e., psychostimulants, opiates, hallucinogens).
It should be emphasized that the adverse reaction to a drug may depend on the unique characteristics of an individual (i.e., presence of cardiovascular disease) as well as the type of drug abused. These protocols serve as guidelines only and an individualized approach to management should be made whenever possible. In the setting of drug overdose, coma usually reflects global depression of the brain’s cerebral cortex. This can be a direct effect of the drug on specific neurotransmitters or receptors or an indirect process such as trauma or asphyxia. Treatment deals largely with maintaining a functional airway, the administration of potential antidotes, and evaluation for underlying medical conditions. The following section describes the Drug rehab thats appropriate use of antidotes and the approach to the patient with a decreased level of consciousness from drug abuse.
Level vs. content of consciousness: It is often useful to distinguish between the level and the content of consciousness. Alertness and wakefulness refer to the level of consciousness; awareness is a reflection of the content of consciousness. In referring to coma, stupor, and lethargy here we address the level of consciousness as it applies to the drug-abusing patient along a clinical spectrum with deep coma on one end, stupor in the middle, and lethargy representing a mildly decreased level of consciousness. Agitation, delirium, and psychosis are addressed in a subsequent section with a greater focus on content of consciousness, i.e., presence or absence of hallucinations, paranoia, severe depression, etc. Attributes of a good antidote The ideal antidote should be safe, effective, rapidly acting, and easy to administer. It should also have low abuse potential, and act as long as the intoxicating drug.
The following standard antidotes are of potentially great benefit and little harm in all patients. Thiamine: Thiamine is an important cofactor for several metabolic enzymes that are vital for the metabolism of carbohydrates and for the proper function of the pentose–phosphate pathway.When thiamine is absent or deficient, Wernicke’s encephalopathy, classically described as a triad of oculomotor abnormalities, ataxia, and global confusion, may result. Although Wernicke’s is rare, empiric treatment for this disease is safe, inexpensive (wholesale price of 100 mg of thiamine is approximately $1), and cost-effective.

Nimodipine: Cocaine is known to decrease reuptake of serotonin, which is believed to play a
role in cocaine-induced headaches and may be associated with cocaine-induced vasoconstriction.
Rothrock et al. reported on three cases of amphetamine-related stroke: in one case a 35-year-old abuser had 20 episodes of transient right hemiparesis occurring within minutes of inhaling methamphetamine; later he developed permanent right hemiparesis. In animal studies,
intravenous methamphetamine administration has resulted in narrowing of the middle cerebral
artery branches within 19 min.While the pharmacologic approaches to cerebral vasospasm are varied, the calcium-channel blocker nimodipine has been used widely with proven efficacy in preventing vasospasm associated with hemorrhagic stroke.No studies looking at this issue in the setting of drug-induced hemorrhagic stroke exist. Although two animal studies found that nimodipine potentiated the toxicity of cocaine and amphetamines in rats, it is felt that in selected
patients the risk–benefit ratio may favor nimodipine administration. Such populations may include the drug-abusing patient who is experiencing transient ischemic attacks closely temporally related to substance abuse or who has had a documented subarachnoid hemorrhage associated with cerebral vasospasm. Recent reports suggest no benefit of nifedipine in ischemic strokes of any type.