Expired-breath ethanol measurement in chronic obstructive pulmonary disease: implications for transurethral surgery

If ethanol is added to the irrigant used during transurethral prostatic resection, the absorption of fluid can immediately be detected by measuring the ethanol concentration in the expired breath. To evaluate this method further, we studied the influence of chronic obstructive pulmonary disease (COPD) on the agreement between expired-breath and blood-ethanol concentrations. In 14 men with a mean age of 62 years (range 55-68), the concentrations of ethanol in whole blood and end-expired breath were measured at 12 exactly timed intervals before, during, and after an intravenous infusion of 0.6 g.kg-1 ethanol for 60 min. The pulmonary function was normal in seven of the subjects (control group) whereas the other seven suffered from severe COPD (study group). The results show that the accuracy and precision of breath-alcohol analysis to predict the blood-ethanol level were poorer during the infusion of ethanol than afterwards. However, at all times of sampling the estimation of blood-ethanol concentration indirectly by analysis of breath was not significantly different for COPD patients and the control group. We conclude that ethanol monitoring of irrigant absorption can be used successfully in patients with COPD.