Urine tests, alcoholism

Pulse oximeter Check blood glucose Check laboratory tests complete blood count serum chemistries liver function tests arterial blood gas blood cultures serum anticonvulsant levels urine drug/alcohol screen... 

Any history of drug or alcohol abuse by a patient should trigger a request for appropriate blood and urine tests. Blood samples should always be taken to assess the levels of study drugs and any concomitant agents used. The drug containers should always be analyzed to confirm their contents. This usually entails sending these drugs to their manufacturer. 

In one particular case, a motorcyclist hit a car and was severely injured. At the hospital, approximately one hour after the accident, the cyclist s blood alcohol content (BAG) was 0.021%. Back extrapolation (see Chapter 7) to the time of the accident could increase that value to 0.036%. His urine tests revealed use of cocaine and marijuana. Marijuana metabolites were confirmed by gas chromatography/mass spectrometry (GC/MS). All these results were used to try and prove that the cyclist was impaired. However, the presence of drug in urine is not a good indicator of drug concentration in blood or of impairment at the time of the accident, and the BAG was probably too low to cause impairment. At best, one could say that the cyclist does use drugs and uses several of them at the same time, but use of the drugs may not have played a role in causing the accident. The case was settled. 

A more down-to-Earth use of fuel cells is found in traffic-law enforcement. Police officers need quick and simple ways to determine a person s blood alcohol level in the field. In the time it takes to bring a person to the station or to a hospital for a blood or urine test, the person s blood alcohol content (BAG) might change. Fuel cells, such as the one in the device shown above, provide a quick and accurate way to measure BAG from a breath sample. The alcohol ethanol from the person s breath is oxidized to acetic acid at the anode. At the cathode, gaseous oxygen is reduced and combined with hydronium ions (released from the anode) to form water. The reactions generate an electric current. The size of this current is related to the BAG. 

Since cocaine withdrawal is generally mUd, treatment of withdrawal symptoms usually is not required (Table 23-8) Rehabilitation programs involving individual and group psychotherapy based on the principles of Alcoholics Anonymous and behavioral treatments based on reinforcing cocaine-free urine tests result in significant improvement in the majority of cocaine users. 

The changes in blood flow velocity observed in our study of marijuana abusers may be due to abuse of substances other than marijuana, since cocaine abusers also show abnormalities in TCD measurements (55). However, the marijuana abusers we recruit for our studies report no substance abuse except for alcohol and nicotine. In fact, prospective subjects who reported other substance abuse or had urine tests positive for other substance were rejected from our marijuana studies. Subjects with excessive use of alcohol are also screened out of our studies. 

Alcohol. The number of driving under the influence of alcohol (DUl) cases reflects the enormity of the dmnken driving problem in the United States (9). Tests to measure blood alcohol concentration are conducted on blood, urine, or breath (10). In the case of urine and breath, the alcohol concentration measured is reported in terms of the equivalent blood alcohol concentration. Most states in the United States presume that a person is under the influence of alcohol with respect to driving a motor vehicle at a blood alcohol concentration of 0.10%, ie, an ethanol concentration >10 g/100 mL of blood. Some states maintain a lower necessary concentration of 0.08%. In some European countries levels are as low as 0.05%. A blood alcohol concentration of 0.10% in a 68-kg (150-lb) person is the equivalent of about four drinks of 80 proof alcohoHc beverage or four 340-g (12-oz) beers in the body at the time of the test (see Beer Beverage spirits, distilled Wine). Ethanol is metabolized at the equivalent rate of about one drink per hour. 

Other Substances. Driving under the influence of alcohol cases are compHcated because people sometimes consume alcohol with other substances (11—13). The most common iUicit substances taken with alcohol are marijuana and cocaine (see Table 1) (14). In combination with alcohol, some dmgs have an additive effect. When a blood or urine alcohol sample is tested for alcohol and the result is well below the legal concentration threshold yet the test results are not consistent with the arresting officers observation that the subject was stuporous, further toxicological tests for the possible presence of dmgs are indicated. 

Because alcohol intoxication may be simulated by many pathologic conditions, including diabetic acidosis, the postconvulsive depression of epilepsy, uremia, head injuries, and poisonings by any other central nervous depressant and some stimulants (280), a diagnosis of acute alcoholism should not be made casually chemical testing of blood, urine, or expired air is always desirable. 

If the test is positive, the urine is examined microscopically for red blood cells. If no red blood cells are found, a tentative diagnosis of myoglobinuria is made, serum chemistries are obtained, and the patient is held to rule out rhabdomyolysis. If the uric acid and creatinine kinase (CK) values are normal, and the patient is asymptomatic, he/she is discharged from the hospital. Routine toxicology tests include urinary PCP, serum alcohol, and hypnotic screen. 

Alcohol consumption is very difficult to assess. There is widespread belief that individuals underreport their intake and there are no reliable laboratory tests available for definitive diagnosis of alcohol abuse. A combination of abnormalities in the plasma activity of gamma-glutamyl transferase (GGT or yGT), AST and reduction in erythrocyte mean cell volume (MCV) maybe useful and all are routine lab. tests. A potential marker of interest is carbohydrate-deficient transferrin (CDT) which is an abnormal isoform of serum transferrin arising due to defects in the attachment of carbohydrate chains to the protein core. Unfortunately, CDT is a somewhat specialized test, not performed by most laboratories. Other markers which have attracted some research interest are ethyl sulphate and ethyl glucuronide. Excretion in the urine of these metabolites occurs for up to 50 hours after binge drinking so they offer a useful index of recent heavy alcohol intake. 

Obermayer s reagent chem A 0.4% solution of ferric chloride in concentrated hydrochloric acid used to test for indican in urine, with a pale-blue or deep-violet color indicating positive. o-b3r,mT-3rz re,a- 3nt n-octadecane orgchem CigHjg Colorless liquid boiling at 318°C soluble in alcohol, acetone, ether, and petroleum, insoluble in water used as a solvent and chemical intermediate. en, ak-t3 de,kan ... 

Testosterone, lljS-hydroxytestosterone, and a polyene alcohol, probably far-nesol, were found in the urine of male yellowfin Baikal sculpin (C. grewingkt). Synthesized in the testes, these compounds are excreted with milt (Katsel etal., 1992). 

Answer to Case A Bloodshot eyes and poor coordination are hallmark signs of marijuana intoxication. The driver may have finished smoking marijuana before getting into the car, explaining the absence of odor, or may have ingested the marijuana. The level of alcohol is too low to account for poor coordination and the failing of the field sobriety tests. A urine sample should be collected and tested by EMIT and, if positive for cannabinoids, confirmed by GC/MS. 

Over 90% of alcohol consumed is oxidized in the liver much of the remainder is excreted through the lungs and in the urine. The excretion of a small but consistent proportion of alcohol by the lungs can be quantified with breath alcohol tests that serve as a basis for a legal definition of "driving under the influence" in many countries. At levels of ethanol usually achieved in blood, the rate of oxidation follows zero-order kinetics that is, it is independent of time and concentration of the drug. The typical adult can metabolize 7-10 g (150-220 mmol) of alcohol per hour, the equivalent of approximately one "drink" [10 oz (300 mL) beer, 3.5 oz (105 mL) wine, or 1 oz (30 mL) distilled 80-proof spirits]. 

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