90% Effective Dose of Norepinephrine Infusions Under Intensive and Standard Treatment
- Conditions
- Adverse Effect
- Interventions
- Drug: Alpha-AgonistDrug: α-adrenergic receptor agonist
- Registration Number
- NCT06151509
- Lead Sponsor
- General Hospital of Ningxia Medical University
- Brief Summary
The objective of this study is to investigate the 90% effective dose of norepinephrine infusions for preventing postspinal anesthesia hypotension under intensive and standard treatment during cesarean section
- 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. The 2016 ASA guidelines for obstetric anesthesia suggest avoiding hypotension following spinal anesthesia in women and emphasize the use of vasopressors, specifically alpha-receptor agonists, as the preferred strategy to prevent and manage post-spinal anesthesia hypotension. The 2018 International Consensus in the United Kingdom and Northern Ireland recommends maintaining maternal systolic blood pressure above 90% of the baseline value following lumbar anesthesia, while avoiding dropping below 80% of the baseline value. Currently, the threshold for maintaining blood pressure above 80% of the baseline value is widely adopted as a standard; however, limited evidence supports the advantage of sustaining maternal blood pressure above 90% of the baseline value. The objective of this study is to investigate the 90% effective dose of norepinephrine infusions for preventing postspinal anesthesia hypotension under intensive and standard treatment during cesarean section.
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- Female
- Target Recruitment
- 80
- 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
- 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 & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Standard group Alpha-Agonist The maternal systolic blood pressure was consistently maintained above 80% of the preoperative baseline value from the initiation of spinal anesthesia until fetal delivery. Intensive group α-adrenergic receptor agonist The maternal systolic blood pressure was consistently maintained above 90% of the preoperative baseline value from the initiation of spinal anesthesia until fetal delivery.
- Primary Outcome Measures
Name Time Method ED50 and ED90 1-15 minutes after spinal anesthesia 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
- Secondary Outcome Measures
Name Time Method The incidence of post-spinal anesthesia hypotension 1-15 minutes after spinal anesthesia. Systolic blood pressure (SBP) \< 80% of the baseline
The incidence of severe post-spinal anesthesia hypotension. 1-15 minutes after spinal anesthesia. Systolic blood pressure (SBP) \< 60% of the baseline.
The incidence of bradycardia. 1-15 minutes after spinal anesthesia. Heart rate \< 60 beats/min.
The incidence of nausea and vomiting. 1-15 minutes after spinal anesthesia. Presence of nausea and vomiting in patients after spinal anesthesia
The incidence of hypertension. 1-15 minutes after spinal anesthesia. Systolic blood pressure (SBP) \>120% of the baseline.
pH Immediately after delivery From umbilical arterial blood gases.
Base excess Immediately after delivery From umbilical arterial blood gases.
Partial pressure of oxygen (PO2) Immediately after delivery From umbilical arterial blood gases.
APGAR score 5 min after delivery A= Appearance P=Pulse G=Grimace A=Attitude R=Respiration; 0(Worst)-10(Best)