Background: Patients who require surgery on the lower extremities are considered to be a high risk group from the point of anesthesia. This study was performed to compare sitting and lateral positions in spinal anesthesia method with hyperbaric bupivacaine 0.5% for hemodynamic status and analgesic period in patients under vascular surgery of the lower limbs in Imam-Khomeini Hospital Complex affiliated to Tehran University of Medical Sciences in 2009.

Methods: In this study 40 patients were divided into two groups of 20 to undergo spinal anesthesia with 3 ml of hyperbaric bupivacaine 0.5% injected into the subarachnoid space in sitting or lateral positions. The anesthesia was performed at T10 level and the hemodynamic status and analgesic periods were compared in the two groups.

Results: The changes in mean arterial blood pressure and systolic and diastolic blood pressures were different between the two groups (P<0.05). Except in the first and thirtieth minutes, the changes in heart rate (HR) were significantly different throughout the study between the two groups (P<0.04) and they were higher in sitting position. The duration of analgesia was significantly longer in lateral position (P<0.04) and the use of fluid was significantly larger in the sitting group (P<0.05).

Conclusion: According to the obtained results, the changes in hemodynamic variables were significantly lower in the group in lateral versus sitting position in patients undergoing spinal anesthesia with bupivacaine for vascular surgery of the lower limb.