Preoperative Risk Factors of Hypotension after Spinal Anesthesia for Elective Cesarean Delivery in Maharat Nakhon Ratchasima Hospital

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Thidarat Ariyanuchitkul


Background: Spinal block is the popular route of anesthesia for cesarean delivery because it entails fewer risks for the mother and the fetus. Maternal hypotension is a common complication after spinal anesthesia resulting in adverse maternal and fetal outcomes. Objectives: To identify risk factors of hypotension in parturients undergoing cesarean delivery under spinal anesthesia. Methods: This was a prospective observational cohort study of the parturients aged 18-45 years undergoing spinal anesthesia for elective cesarean delivery at Maharat Nakhon Ratchasima Hospital during March 2020 and March 2021. The collected parameters were demographic data, anesthetic data and vital signs after spinal anesthesia. Hypotension was defined as a decrease of systolic blood pressure of more than 20% and less than 90 mmHg. Univariable and multivariable logistic regression were performed for identify risk factors of hypotension after spinal anesthesia. Results: Hypotension was found in 303 from 636 cases (47.6%). Preoperative factors identified the height, BMI, gestational age, estimated baby weight, baseline systolic blood pressure, baseline mean arterial pressure, oxygen saturation and sensory block level as the risk factors of hypotension after spinal anesthesia. The multivariate analysis identified estimated baby weight 2500-3900 gm, >4000 gm and sensory block level >T6 associated with hypotension after spinal anesthesia (adjusted odds ratio 5.29, 8.77 and 1.97). Conclusion: The risk factors associated with increased incidence of hypotension are the estimated baby weight >2500 gm and sensory block level >T6.

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