Different Crystalloid Coload Volumes on the 90% ED of Norepinephrine

Up-and-Down Determination of Different Crystalloid Coload Volumes on the 90% Effective Dose of Prophylactic Norepinephrine Infusions for Preventing Postspinal Anesthesia Hypotension During Cesarean Section

The purpose of this study is to investigate the effect of different crystalloid coload volumes on the 90% effective dose of prophylactic norepinephrine infusions for preventing postspinal anesthesia hypotension during cesarean section.

Study Overview

• Status: Completed
• Conditions: Adverse Effect
• Intervention / Treatment: Drug: Crystalloid - 0 ml/kg; Drug: Crystalloid - 5 ml/kg; Drug: Crystalloid - 10 ml/kg

Detailed Description

Post-spinal anesthesia hypotension is a frequent complication during spinal anesthesia for cesarean section. The incidence of post-spinal anesthesia hypotension is as high as 62.1-89.7% if prophylactic measures are not taken. Coload has been highly demonstrated for prevention and/or treatment of post-spinal anesthesia hypotension. In addition, there's some evidence that prophylactic infusion of norepinephrine could effectively reduce the incidence of post-spinal anesthesia hypotension in parturients undergoing cesarean section. The purpose of this study is to investigate the effect of different crystalloid coload volumes on the 90% effective dose of norepinephrine infusion prophylaxis for hypotension during spinal anesthesia for cesarean section.

• Study Type: Interventional
• Enrollment (Actual): 90
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Ningxia
    • Yinchuan, Ningxia, China, 750004
      • General Hospital of Ningxia Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 18-45 years
• Primipara or multipara
• Singleton pregnancy ≥37 weeks
• American Society of Anesthesiologists physical status classification I to II
• Scheduled for cesarean section under spinal anesthesia

Exclusion Criteria:

• Body height < 150 cm
• Body weight > 100 kg or body mass index (BMI) ≥ 40 kg/m2
• Eclampsia or chronic hypertension or baseline blood pressure ≥180 mmHg
• Hemoglobin < 7g/dl
• Fetal distress, or known fetal developmental anomaly

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Control group; No fluid coload was given. An initial infusion dose of prophylactic norepinephrine simultaneous with spinal anesthesia	Drug: Crystalloid - 0 ml/kg; No fluid coload was given. An initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.; Other Names: Crystalloid
Experimental: Crystalloid - 5 ml/kg; 5 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine simultaneous with spinal anesthesia.	Drug: Crystalloid - 5 ml/kg; 5 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.; Other Names: Crystalloid
Experimental: Crystalloid - 10 ml/kg; 10 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine simultaneous with spinal anesthesia.	Drug: Crystalloid - 10 ml/kg; 10 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.; Other Names: Crystalloid

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ED50 and ED90	The dose of prophylactic norepinephrine that would be effective in preventing postspinal anesthesia hypotension in 50% (effective dose, ED 50) and 90% (ED90) of patients	1-15 minutes after spinal anesthesia

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incidence of post-spinal anesthesia hypotension	Systolic blood pressure (SBP) < 80% of the baseline	1-15 minutes after spinal anesthesia
The incidence of severe post-spinal anesthesia hypotension	Systolic blood pressure (SBP) < 60% of the baseline	1-15 minutes after spinal anesthesia
The incidence of nausea and vomiting	Presence of nausea and vomiting in patients after spinal anesthesia	1-15 minutes after spinal anesthesia
The incidence of bradycardia	Heart rate < 60 beats/min	1-15 minutes after spinal anesthesia
APGAR score	A= Appearance P=Pulse G=Grimace A=Attitude R=Respiration	1 minute after delivery
The incidence of hypertension	Systolic blood pressure (SBP) >120% of the baseline	1-15 minutes after spinal anesthesia
pH	From umbilical arterial blood gases	Immediately after delivery
Partial pressure of oxygen (PO2)	From umbilical arterial blood gases	Immediately after delivery
Base excess (BE)	From umbilical arterial blood gases	Immediately after delivery
APGAR score	A= Appearance P=Pulse G=Grimace A=Attitude R=Respiration	5 minute after delivery

Collaborators and Investigators

• Sponsor: General Hospital of Ningxia Medical University
• Investigators: Study Chair: Yi Chen, M.D., General Hospital of Ningxia Medical University; Study Chair: Xiangsheng Xiong, M.D., The Fifth People's Hospital of Huaian

Study record dates

Study Major Dates

• Study Start (Actual): March 21, 2023
• Primary Completion (Actual): June 16, 2023
• Study Completion (Actual): June 16, 2023

Study Registration Dates

• First Submitted: January 10, 2023
• First Submitted That Met QC Criteria: January 10, 2023
• First Posted (Actual): January 19, 2023

Study Record Updates

• Last Update Posted (Actual): June 22, 2023
• Last Update Submitted That Met QC Criteria: June 18, 2023
• Last Verified: June 1, 2023

More Information

Terms related to this study

• Keywords: Cesarean section; Norepinephrine; Postspinal anesthesia hypotension; Coload
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension
• Other Study ID Numbers: Yi Chen-2023-2

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No