The efficacy of gastric lavage as it is practiced in a major metropolitan hospital was evaluated. From a population of 76 patients with chemical evidence of sedative-hypnotic drugs in the blood, two or more therapeutic doses were recovered from 15.8% of the lavage samples, and 10 or more therapeutic doses were recovered from 6.6%. In a population consisting of patients with detectable quantities of drugs in the lavage sample, diazepam and amitriptyline are more adequately recovered than the sedative-hypnotic drugs. Very poor recoveries were obtained in patients lavaged more than 2 h after ingestion except in cases of amitriptyline overdose or massive sedative-hypnotic ingestion. The study indicates that inadequate criteria are employed in selecting patients most likely to benefit from lavage. Dose, time since ingestion, and symptomatology are discussed as criteria for selection of patients for lavage.

The mean total body water was determined by desiccation in DBA/2J, CBA/J, and C57BL/6J mice to be 60.6, 65.6, and 68.6 percent of body weight, respectively. The pharmacokinetics of ethanol was subsequently studied in mice of these strains given an intraperitoneal dose of 116 mmoles/l of total body water based on the desiccation study. This dose was equivalent to 70, 76, and 80 mmoles/kg in the DBA/2J, CBA/J, and C57BL/6J strains, respectively. The zero time concentrations were nearly identical between strains; therefore volume of distribution (VD) estimates based on mmole/kg doses reflected interstrain differences in total body water. The apparent zero order elimination rate was significantly greater in the DBA/2J strain versus the other two strains using this regimen. Interstrain differences in ethanol sleep time paralleled the differences in anesthetic sensitivity evidenced by blood concentrations at the time of regaining the righting reflex. The results demonstrate the importance of considering differences in total body water and hence ethanol VD when comparing the effects of ethanol in inbred mouse strains.

The efficacy of administering a slurry of 100 g of activated charcoal (AC) via the gastric tube following lavage was assessed in 25 treated and 37 control patients presenting to the emergency room with chemical evidence of sedative-hypnotics or aspirin in the blood. Efficacy was evaluated as the ability of AC to prevent further absorption as determined by subsequent blood drug concentration changes. Although fewer patients in the AC group showed increased blood drug concentrations, the differences were not statistically significant. Comparison of the mean percent change in blood drug concentrations at various times following treatment produced similar results. Comparisons using subgroups of patients based on the individual drugs, the treatment delay time, and entering functional decompensation showed significant benefit from AC only in the less symptomatic patients. Comparing these results with other studies demonstrating the unequivocal efficacy of early (e.g., 30 min) treatment, it is concluded that the use of AC following lavage may often be too late to benefit most patients. The authors suggest that AC be given in the home, emergency vehicle, or immediately upon admission.