Respiratory depression produced by diazepam in cats: effect of anaesthesia

Diazepam (Valium, Roche; 0.37 mg/kg was given by slow injection into the left femoral vein and flushed in with 0.9 % saline. Within 3 min following the i.v. injection of diazepam spontaneous respiration ceased in rats anaesthetized with chloralose; mean arterial pressure fell from a control level of 99.4 (+/- 28.3) mmHg to 32.5 (+/- 13.44) mmHg. If artificial ventilation was initiated immediately upon cessation of respiration, the animal recovered. Cats anesthetized with ketamine (Ketaset, Roger; 44 mg/kg i.m.) showed no respiratory depression following i.v. diazepam injection.