Diazepam and meperidine on arterial blood gases in patients with chronic obstructive pulmonary disease.

Arterial blood gases were not significantly altered by 0.15 mg/kg intravenous dose of diazepam in patients with chronic obstructive lung disease. The PalphaO-2 was significantly reduced and the P-alphaCO-2 increased after administration of 1.5 mg/kg meperidine intravenously and the combination of 1.5 mg/kg meperidine with 0.15 mg/kg diazepam. Diazepam did not, however, significantly increase the ventilatory depression induced by meperidine. Therefore, 0.15 mg/kg diazepam intravenously causes no ventilatory depression by meperidine in patients with chronic obstructive lung diseases.