The Effects of Intravenous diazepam on Arterial Blood Gas and Mean Arterial Pressure in patient under Spinal Anesthesia

Ji, Jae Sool; Yoon, Myung Ha; Jeong, Chang Young

Abstract

Many patients,especially in certain high risk groups, undergo operative procedures under regional anesthesia in belief that this approach is safer than general anesthesia. During the regional anesthesia, sedation is often provided with intravenous agents, such as diazepam even if diazepam has some dipressant effects on respiration and hemodynamics. To evaluate the effects of diazepam on spinal anesthesia, arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2), arterial oxygen saturation (SaO2) and mean arterial pressure (MAP) were measured at 1,3,5.10,15,20and 30min. following diazepam iv (0.2 mg/kg) under spinal anesthesia (group 2), and were compared with the changes in the control group (group 1), who received spinal anesthesia without diazepam administration. The results were as follows: 1) MAP revealed no significant decrease in the control group, and decreased significantly in the group 2 from 3 to 30 min. after diazepam iv under spinal anesthesia. 2) PaO2 did not change significantly in the control group, but PaO2 in group 2 decreased significantly at 1 and 10 min. after intravenous administration of diazepam. And the changes from 3 to 20 min. after intravenous administration of diazepom were significantly different from changes in the group 3) PaO2 increased significantly in grorp 2 from 3 min. after diazepam iv which were significantly different from the changes in the control group. 4) SaO2 decreased significantly in group 2 from 1 to 30 min. after diazepam iv which were significantly different from the changes in the control group. From the above results, diazepam administration under spinal anesthesia affects the respiratory function and hemodynamics, so oxygen inhalation technique may be needed in most cases of sedatives administration after spinal anesthesia.