Effects of Sedation on Spinal Anesthesia-induced Maternal Hypotension in Preoperatively Anxious Parturients Underwent Urgent Category-1 Cesarean Section: A Historical Cohort Study

Objective: This study was designed to investigate the effect of sedation on maternal hypotension in preoperatively anxious parturients underwent urgent category-1 Cesarean section (C/S) under spinal anesthesia (SA). Material and Methods: After ethics committee approval, data of 1824 parturients underwent C/S were reviewed from the surgical database and patient charts. Parturients with high preoperative anxiety scores (VAS-A)≥70) underwent C/S under SA with thiopental 2 mg/kg (if necessary additional 50 mg) sedation until reaching Ramsay sedation score≥3 (Group S, n=49), and without any other type of sedation (Group NS, n=53) were included in the study. All parturients received SA with hyperbaric bupivacaine 0.5% 2.5 mL. Hemodynamic parameters and maximum systolic arterial pressure (SAP) reductions (%) from the baseline were recorded. Maternal hypotension (SAP≥30% decrease or <100 mmHg) and bradycardia (heart rate <55 beats/min) incidences, required ephedrine (5mg IV bolus) and atropine (0.5 mg IV bolus) doses, and newborn Apgar scores were also analyzed. Results: Fifty-nine parturients' data (Group S: 29 and Group NS: 30) were analyzed. The maximum SAP reductions were 23±12.8% and 30.8±16.1% in Groups S and NS, respectively (p=0,044). Hypotension was observed in 5 (17,2%) parturients of Group S and 15 (50%) of Group NS (p=0.012, 95% CI 0,14-0,82; relative risk=0,344). Ephedrine requirement was 17±4,4 mg and 25±7,4 mg in Groups S and NS, respectively (p=0,04). Incidence of bradycardia, required atropine dose and newborn Apgar scores were similar in both groups (p>0,05). Conclusions: The maximum SAP reduction, hypotension incidence and required ephedrine doses were lower in thiopental sedation used preoperatively anxious parturients who underwent category-1 C/S under SA.