Use of an alcometer in a casualty department

Detection of problem-drinkers in an emergency department using a breathalyser and questionnaire

Over a 2-week period in January 1990 consecutive adult emergency attenders were breathalysed and screened for problem drinking using the WHO screening instrument. Results were compared with a similar study conducted 8 years previously. Of the patients tested, 12.5% had a positive alcohol in 1990 compared with 16% in 1982. Of those with positive alcohol results, the mean blood alcohol equivalent (BAE) concentration was significantly (p=0.0006) lower in 1990 (73.6+/-65.1; mg/100 ml; mean+/-SD) when compared to those levels found in 1982 (136.9+/-102.4 mg/100 ml). There was also significant reductions in 1990 of positive breath alcohol attenders both from road traffic accidents (p<0.03), and from head injuries (p<0.005) compared to 1982. In 1990 the questionnaire was positive in 23% of attendees. These studies suggest a trend towards less alcohol misuse in emergency department patients, but nevertheless indicate high rates of problem drinking. It is suggested that alcohol breathalysers be available in emergency departments to assist the detection of alcohol misusers and predict alcohol-associated medical problems.

An evaluation of sensitivity and specificity of blood alcohol concentrations obtained by a breathalyser survey in a casualty department in Kenya

Whereas breathalysers have been shown to provide blood alcohol concentration (BAC) measurements comparable to those obtained by gas chromatography, such evidence has not been reported in low and middle income countries where measures for preventing alcohol-related injuries are virtually non-existent. Before promoting any method of blood alcohol evaluation, as a routine procedure for monitoring the association of alcohol with different types of injuries in Kenya, we sought to assess the reliability and validity of blood alcohol results obtained by a breathalyser, using gas chromatography analysis values as the reference, in a sample of 179 trauma-affected adults presenting to casualty departments. No differences in proportions of subjects with high levels of blood alcohol (equal to or greater than 50 mg%) were detected by breath and blood test procedures (58.7 vs 60.3%). Breathalyser readings yielded high levels of sensitivity and specificity (97.2 and 100%, respectively) with optimal positive and negative predictive values (100 and 95.9%, respectively) at higher BACs (> or = 50 mg%). The study thus reaffirms that breathalyser tests are of value in detecting high blood alcohol levels and can be used to rapidly identify intoxicated subjects. The procedure is easy to perform and can be used for monitoring the association between blood alcohol level and driving in low-income developing countries.

Accuracy of an enzymatic assay device for serum ethanol measurement

OBJECTIVE

To determine the accuracy of an enzymatic assay of serum to measure blood ethanol levels in the emergency department.

METHODS

A blinded, prospective study of emergency department patients for whom a blood ethanol was ordered and performed. After skin prep with betadine, two blood samples were drawn into separate sodium fluoride-containing vacutainers. One sample was sent to the hospital laboratory for blood ethanol analysis. The other was centrifuged for 5 minutes and the serum was then assayed using the QED A350 Saliva Alcohol Test. Values were then compared by kappa statistic and Pearson's correlation. Sensitivity and specificity calculations were determined for the QED device to detect a blood ethanol > 100 mg/dL.

RESULTS

Sixty-six patients were enrolled. The kappa value for QED compared to lab blood ethanol was 0.93. The Pearson's correlation coefficient was 0.94. The QED, in general, tended to overestimate blood ethanol slightly. The QED was 100% sensitive and 82% specific in detecting a blood ethanol > 100 mg/dL.

CONCLUSIONS

Analysis of serum using a QED A350' is a sensitive and accurate index of low to moderate increases in blood ethanol appropriate to emergency department, but not legal, interpretation.

Characteristics of a new urine, serum, and saliva alcohol reagent strip

We have tested an ethanol reagent strip developed at the Addiction Research Foundation of Ontario. Alcohol dehydrogenase and nicotinamide adenine dinucleotide, in the presence of pyrazole, react with ethanol to yield acetaldehyde plus reduced nicotinamide adenine dinucleotide. The latter reduces iodonitrotetrazolium chloride in the presence of diaphorase, generating an intense red color. The rate of color development is proportional to the concentration of ethanol. Color is compared at a specific time against a calibrated color scale ranging from green (negative) to red, representing alcohol concentrations of 0, 25, 50, 100, 200, and 400 mg/dl (0-0.4%; 0-87 mmol/liter). We were able to interpolate the color observed between the calibrated blocks. When tested on urine, serum/plasma, and saliva, ethanol concentration determined by the reagent strip correlates well with ethanol concentration as determined by gas chromatography or by automated enzymatic analysis (r = 0.92-0.98, p less than 0.001; slope 0.83-1.16). The reagent strip was shown to be used appropriately by nonexperienced individuals following a 1-min explanation (reagent strip values, r = 0.92; p less than 0.001, slope = 0.97, versus gas chromatography). The reagent strip does not react with methanol (wood alcohol), isopropanol (rubbing alcohol), and ethylene glycol (antifreeze) often found in accidental poisonings. In 379 clinical samples obtained without exclusion criteria from 12 hospital emergency rooms and a liver clinic, the sensitivity of the reagent strip in detecting ethanol was 98%. Specificity was 99%. The reagent strip was found to have virtually unlimited stability under refrigeration (4 degrees C) and to be stable for 3 to 4 months at room temperature (22-23 degrees C).(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid quantitative determination of blood alcohol concentration in the emergency department using an electrochemical method

STUDY OBJECTIVE

To determine the reliability of a recently developed electrochemical meter to rapidly (within 60 seconds) measure blood alcohol concentration (BAC) in the emergency department.

DESIGN

A prospective study comparing the meter data with that of immunoassay and gas chromatography criterion standards undertaken during a ten-week period.

SETTING

Adult ED of a municipal hospital.

PARTICIPANTS

Three hundred eighty-three consecutive patients with altered mental status or suspected alcohol intoxication.

INTERVENTIONS

Each patient underwent routine phlebotomy, and blood samples were obtained for meter and immunoassay BAC determinations. The first 60% of patients also underwent gas chromatography BAC determination.

RESULTS

Two hundred nineteen patients (60%) had BAC detectable by both meter and immunoassay. BAC measurement by the meter correlated strongly with immunoassay and gas chromatography determinations (Pearson's correlation coefficient, r = .94; P less than .00000001 for both correlations).

CONCLUSION

The electrochemical meter provides a rapid and reliable BAC measurement in the ED.

Noninvasive estimation of blood alcohol concentrations: ethanol vapor above the eye

The present study describes, in animals, a novel approach to the in vivo, noninvasive determination of alcohol in the body. The concentration of ethanol in vapor above the lacrimal fluid in the eye was analyzed in situ by the use of a fast (1-min) gas sensor method developed previously for biological liquids. After an oral dose of 1 g/kg to 11 animals, eye vapor measurements and blood samples were obtained over 4 hr. The correlation of 61 blood ethanol concentrations obtained by the two methods yielded a correlation coefficient of 0.92 and a slope of 0.99. The metabolic rates of ethanol determined by gas chromatographic analysis of blood and by ethanol eye vapor analysis are virtually identical. The data suggest that ethanol eye vapor analysis may be an attractive, noninvasive method for the determination of ethanol in animals. The method is not subject to false high readings due to alcohol in the buccal cavity and thus might constitute an alternative to breath analysis in the human. In a separate series, ethanol was determined by head space gas chromatography in samples of blood and lacrimal fluid while the animals were under ketamine anesthesia. The correlation of ethanol concentrations in blood and lacrimal fluid (r = 0.99) shows that ethanol is distributed in lacrimal fluid which comprises part of total body water.

The detection of alcohol use in psychiatric casualty patients

This study assessed the extent of alcohol use among casualty attenders at a metropolitan psychiatric hospital. Seventeen of 97 patients showed measurable alcohol levels at the time of presentation. Patients with functional psychoses used alcohol excessively, but the heaviest and most frequent use was among women, especially those with personality disorders. It is suggested that routine alcohol testing is worthwhile and inexpensive, and it may lead to earlier detection and treatment of alcohol abuse.