ABSTRACT
We have studied the effect of sedation with diazepam on arterial oxygen saturation during spinal anestheia in two groups of patients: Group I: Received diazepam (0.2 mg/kg i.v.) after the level of spinal anesthesia was determined, and breathed the room air. The level of sedation was controlled such that the patient was drowsy but aroused easily and capable of communication. An additional dose of diazepam was given when required. (n=15) Group II: Received diazepam (0.2 mg/kg i.v.) in the same manner as Group I but with supplementary oxygen inhalation (3l/min) through the nasal catheter. (n = 15) The results were as follows: Two of 15 patients of Group I who were given sedation during spinal anesthesia and who breathed room air developed moderate hypoxemia, with a SaO2 of 88-89%. There were no episodes of hypoxemia in Group II patients who received supplementary oxygen inhalation. We concluded that oxygen should be administered routinely to patients receving diazepam as a sedative during spinal anesthesia for the prevention of hypoxemia, unless a pulse oximeter is available to monitor SaO2.