Correlation Between Body Mass Index and Hypotension in Patients Undergoing Caesarian Section Under Spinal Anesthesia At Hayatabad Medical Complex

Abstract

Background

Very few publications correlate hypotension in obese pregnant women, especially morbidly obese, after spinal anesthesia for cesarean section. The objective of the present study was to evaluate the incidence of hypotension according to the BMI.

Materials and Methods:

This study was carried out between November and December 2019 at Hayatabad Medical Complex (HMC). The objective was to determine and compare the frequency and severity of hypotension in parturients with high maternal BMI (25) and those with normal BMI (18.5-34.9) during spinal anesthesia. We designed a comparative cross-sectional study. The study population included all women of childbearing age undergoing cesarean section in HMC. The sample population was divided into two groups. One group was women who were obese with BMI30 (94 women) and the other group was women with normal BMI i.e., 18.5-24.9. (102 women)

Results:

The outcome of interest was the development of hypotension during spinal anesthesia and its severity and a comparison was made between the two groups. The incidence of hypotension in the obese group of women was 79 (84.0%) as compared to those with normal BMI whose incidence was 70(70.0%). Obese patients were more likely to have moderate or severe hypotension (30.6% and 19.4%, respectively) compared to normal weight (11.8% and 3.3% respectively) patients undergoing cesarean delivery under spinal anesthesia and on average the blood pressure was reduced by 0,6% from the baseline level for each unit increase in BMI. There was no significant difference in the fluid volumes used intra-op between the two groups and neither did it differ with the severity of hypotension. (p=0.513)

Conclusion:

Pregnancy and obesity are both independently associated with increased anesthetic risks. This study sought to determine the incidence and severity of hypotension in patients with a raised BMI undergoing CS under spinal anesthesia in Hayatabad Medical Complex HMC hospital, Pakistan.

In conclusion, the study showed a higher incidence of hypotension in obese parturient women with an average blood pressure reduction of 0.6% from the baseline level for each unit increase in BMI. There was no significant difference in the fluid volumes used intra- op between the two groups. Synephrine and atropine were mainly used to correct hypotension with higher doses required in the obese patient