Effects of Sedation on Spinal Anesthesia-induced Maternal Hypotension

Background: This study was designed to investigate the effect of sedation on the occurrence of maternal hypotension in preoperatively anxious parturients undergoing urgent category-1 Cesarean section (C/S) under spinal anesthesia.

Methods: After institutional ethics committee approval, prospectively collected data of 1824 parturients undergoing C/S were reviewed. Parturients with high preoperative anxiety scores (visual analogue scale for anxiety (VAS-A)≥70) undergoing C/S under spinal anesthesia with thiopental (Group S=49) and without any other type of sedation (Group NS=53) were included in the analysis. Hemodynamic parameters were documented and maximum systolic arterial pressure (SAP) reductions from the baseline after spinal anesthesia were calculated. Incidences of hypotension (SAP≥30% decrease from baseline or \<100 mmHg) and bradycardia (HR\<55 beats/min), and related-ephedrine and -atropine requirements were noted. Our primary endpoint was to compare the maximum SAP reductions from the baseline values in Groups S and NS. Secondary endpoints were incidences of hypotension and bradycardia, required ephedrine and atropine doses, newborn Apgar scores at 1st and 5th min.

Background: This study was designed to investigate the effect of thiopental sodium sedation on the occurrence of maternal hypotension in preoperatively anxious parturients undergoing urgent category-1 Cesarean section (C/S) under spinal anesthesia.

Methods: After institutional ethics committee approval, prospectively collected data of 1824 parturients undergoing C/S at Van Training and Research Hospital between August 2014 and February 2015 were reviewed. Parturients with high preoperative anxiety scores (visual analogue scale for anxiety (VAS-A)≥70) undergoing C/S under spinal anesthesia with thiopental (Group S=49) and without any other type of sedation (Group NS=53) were included in the analysis. All parturients received SA with hyperbaric bupivacaine 0.5% 2.5 mL. Hemodynamic parameters were documented and maximum systolic arterial pressure (SAP) reductions from the baseline after spinal anesthesia were calculated. Incidences of hypotension (SAP≥30% decrease from baseline or \<100 mmHg) and bradycardia (HR\<55 beats/min), and related-ephedrine and -atropine requirements were noted. All data were obtained from the surgical database and patient charts. Primary endpoint of our study was to compare the maximum SAP reductions from the baseline values in Groups S and NS. Secondary endpoints were incidences of hypotension and bradycardia, required ephedrine and atropine doses, newborn Apgar scores at 1st and 5th min.

Eligibility Criteria:
Inclusion Criteria:

* Urgent category-1 C/S
* ASA physical status I-II
* Aged between 18 and 35 years
* Term (≥37 weeks) singleton pregnancy
* BMI \<40 kg/m2
* Height \>150 cm or \<180 cm
* High preoperative anxiety scores (visual analogue scale for anxiety (VAS-A) ≥70)
* Spinal anesthesia with thiopental sodium sedation
* Spinal anesthesia without any sedation

Exclusion Criteria:

* Preoperative prehydration
* Placenta previa
* Placenta accreta
* Hypertension
* Pregnancy-induced hypertension
* Urgent category ≥2
* General anesthesia
* Spinal anesthesia with sedation other than thiopental sodium