Study objective: To determine the presence of cocaethylene, an active
metabolite of the combination of cocaine and ethanol, among trauma pat
ients who test positive for cocaine. Methods: We assembled a case seri
es of 416 consecutive urban trauma center patients with major trauma.
Urine was tested for the presence of the cocaine metabolite benzoylecg
onine. Plasma was quantitatively assayed for cocaine, ethanol, and coc
aethylene. Results: Of the study subjects, 158 (38%) were positive for
benzoylecgonine; Of the 114 of these subjects who had adequate plasma
specimens, 68 (60%) tested positive for cocaethylene (mean, 41+/-27 n
g/ml; range, 3 to 213 ng/mL), all tested positive for cocaine (mean, 9
2.9+/-52 ng/mL), and 56% were positive for ethanol (mean, 175+/-85 mg/
dL). We found poor correlation between admission levels of cocaethylen
e and cocaine (R=.02), even when subjects were stratified by ethanol l
evel. The correlation between cocaethylene and ethanol levels was weak
(R=.24). Of the 68 patients who tested positive for cocaethylene, 29%
tested negative for ethanol. Plasma was also assayed from 94 subjects
who tested negative for benzoylecgonine; 9% had detectable levels of
cocaine, and 2% had detectable levels of cocaethylene. Conclusion: Coc
aethylene was present in more than half of the subjects who tested pos
itive for cocaine.