The Effect of Sitting versus Lateral Position during Induction of Spinal Anesthesia for Cesarean Section

Abstract

Backgroundand Objective :  Hypotension is a common problem after spinal anesthesia for cesarean section.This prospective randomized single blinded study was aimed to study the effect on hypotension and the onset time to anesthetic level between sitting versus lateral position during induction of spinal anesthesia for cesarean section in the operating room of Pathumthani hospital.

Methods :  Eighty ASA physical status I-II patients scheduled for elective cesarean section were randomly assigned to have spinal anesthesia induced either in the right lateral (group L) or sitting (group S) positions . Intrathecal injection of 10 milligrams of hyperbaric bupivacaine 0.5% associated with 200 micrograms of morphine was performed over 20 seconds before patient was placed in a supine position with left uterine displacement. The time to site spinal needle, time to reach T4 dermatome, the anesthetic level, blood pressure, ephedrine used for treatment of hypotension and patient satisfaction were recorded.

Results :  The incidence of  hypotension in the L group was significantly higher when compared with the S group (40% vs 22.5%,  p= 0.04). Onset time to anesthetic level T4 in the L group was faster than the S group (4.82 + 2.58 min vs 6.35 + 3.11 min, p = 0.04). Patient in group L required more ephedrine (13.95 + 8.13  mg vs 7.01 + 6.43 mg, p < 0.001). It took longer time to site spinal needles in the lateral position (5.99 + 3.58 min vs 3.01 + 1.02 min, p < 0.001). Fluid used were not significantly different between two groups. There was no difference in neonatal outcome and patient’s satisfaction between two groups.

Conclusion :  The presented study has shown that the incidence of maternal hypotension after induction of spinal anesthesia for cesarean section is lower in sitting position when compared with a lateral position but time to anesthetic level to T4 was slower.