Effects of Sedation on Spinal Anesthesia-induced Maternal Hypotension

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

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.

Study Overview

• Status: Completed
• Conditions: Cesarean Section; Preoperative Anxiety; Spinal Anesthesia; Sedation; Maternal Hypotension
• Intervention / Treatment: Drug: Sedation; Drug: No sedation

Detailed Description

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.

• Study Type: Observational
• Enrollment (Actual): 102

Contacts and Locations

Study Locations

• Turkey
  • Van, Turkey
    • Van Training and Research Hospital, Department of Anesthesiology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Parturients undergoing urgent category-1 Cesarean section (C/S) under spinal anesthesia

Description

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

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Sedation (S); Parturients who received IV thiopental 2 mg kg-1 and if necessary additional 50 mg immediately after spinal anesthesia until reaching at least Ramsay sedation score of 3 (1: patient anxious, agitated or restless, 6: patient with no response to light glabella tap or loud auditory stimulus.).	Drug: Sedation; Parturients who received IV thiopental 2 mg kg-1 and if necessary additional 50 mg immediately after spinal anesthesia until reaching at least Ramsay sedation score of 3 (1: patient anxious, agitated or restless, 6: patient with no response to light glabella tap or loud auditory stimulus.).; Other Names: Thiopental
No sedation (NS); Parturients who did not receive any sedative agent after the spinal anesthesia performance.	Drug: No sedation; Parturients did not receive any type of sedation after spinal anesthesia.; Other Names: No drug

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum systolic arterial pressure (SAP) reductions from the baseline values	% SAP reduction after spinal anesthesia	0-10 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of maternal hypotension	Incidence of hypotension during the surgery (decrease in SAP >30% from baseline or an absolute value <100 mmHg)	0-30 minutes
Incidence of maternal bradycardia	Incidence of bradycardia during the surgery (heart rate (HR) <55 beats min-1)	0-30 minutes
Ephedrine requirement	Ephedrine 5 mg IV boluses were administered with 2 min intervals until SAP returned to a value of >100 mmHg	0-30 minutes
Atropine requirement	Bolus of IV 0.5 mg atropine was given if bradycardia (HR <55 beats min-1) occurred	0-30 minutes
Incidence of maternal nausea	If any during the Cesarean section, recorded	0-30 minutes
Incidence of maternal vomiting	If any during the Cesarean section, recorded	0-30 minutes
Newborn Apgar score 1st min	Apgar score at 1st min (0-3: severely depressed, 4-6: moderately depressed, 7-10: excellent condition)	1st min
Newborn Apgar score 5th min	Apgar score at 5th min (0-3: severely depressed, 4-6: moderately depressed, 7-10: excellent condition)	5th min

Collaborators and Investigators

• Sponsor: Van Training and Research Hospital
• Investigators: Principal Investigator: Cenk Sahan, MD, Design and conduct the study, review and analyze the data, and write the manuscript

Publications and helpful links

General Publications

• Orbach-Zinger S, Ginosar Y, Elliston J, Fadon C, Abu-Lil M, Raz A, Goshen-Gottstein Y, Eidelman LA. Influence of preoperative anxiety on hypotension after spinal anaesthesia in women undergoing Caesarean delivery. Br J Anaesth. 2012 Dec;109(6):943-9. doi: 10.1093/bja/aes313. Epub 2012 Sep 10.

Study record dates

Study Major Dates

• Study Start: August 1, 2014
• Primary Completion (Actual): February 1, 2015
• Study Completion (Actual): February 1, 2015

Study Registration Dates

• First Submitted: April 4, 2016
• First Submitted That Met QC Criteria: April 4, 2016
• First Posted (Estimate): April 8, 2016

Study Record Updates

• Last Update Posted (Estimate): April 11, 2016
• Last Update Submitted That Met QC Criteria: April 8, 2016
• Last Verified: April 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Hypnotics and Sedatives; GABA Modulators; GABA Agents; Anticonvulsants; Thiopental
• Other Study ID Numbers: 2015/4

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO