Assessment of the Relation between Body Mass Index, Intra-Abdominal Pressure and Abdominal Girth of Pregnant Women and the Development of Hypotension after Spinal Anesthesia for Cesarean Section

Abstract

Background: One typical adverse effect of spinal anesthesia in parturient is hypotension. 50% to 80% of cases are reported. It grows in direct proportion to the degree of sensory blockage and sympathetic blockade. Objective: To evaluate the relationship between intra-abdominal pressure, abdominal girth and body mass index and developing hypotension during elective Cesarean Section under Spinal Anesthesia. Patients and methods: This prospective observational study was carried out at the operating theaters in Suez Canal University hospital in Ismailia in the period from 2020 to 2023, on 130 full term pregnant women, included full term pregnant women aged between 20- and 40-years undergoing elective Cesarean Section under Spinal Anesthesia. Results: SBP and MAP had significant indirect correlations with BMI (r= -.667, p <.001, r= -.667, p <.001 respectively), IAP (r= -.740, p <.001, r= -.738, p <.001 respectively), AC (r= -.741, p <.001, r= -.738, p <.001 respectively), fluid used (r= -.761, p <.001, r= -.755, p <.001 respectively), and ephedrine used (r= -.434, p <.001, r= -.428, p <.001 respectively). Linear regression analysis showed BMI (B= -0.419, p < 0.001) IAP (B= 3.262, p=0.003) and AC (B= -0.377, p=0.012) were significant negative predictors for the occurrence of hypotension. Conclusion: Following spinal anesthesia, MAP in pregnant women with higher BMIs dropped considerably from baseline. Both the BMI and the AC are non-operator dependent and are readily and noninvasively assessed.