90% Effective Dose of Norepinephrine Infusions for Preventing Postspinal Anesthesia Hypotension Under Intensive and Standard Treatment in Preeclamptic Patients During Cesarean Section
Trial Snapshot
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Sponsor
- Enrollment
- 80
- Primary Endpoint
- ED50 and ED90
Study Overview
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 in preeclamptic patients 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 in preeclamptic patients during cesarean section.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Double (Participant, Care Provider)
Eligibility Criteria
- Ages
- 18 Years to 45 Years (Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •18-45 years
- •Primipara or multipara
- •Singleton pregnancy ≥32 weeks
- •American Society of Anesthesiologists physical status classification I to III
- •Scheduled for cesarean section under spinal anesthesia
Exclusion Criteria
- •Baseline blood pressure ≥160 mmHg
- •Body height < 150 cm
- •Body weight > 100 kg or body mass index (BMI) ≥ 40 kg/m2
- •Eclampsia or chronic hypertension
- •Hemoglobin < 7g/dl
- •Fetal distress, or known fetal developmental anomaly
Arms & Interventions
Standard group
The maternal systolic blood pressure was consistently maintained above 80% of the preoperative baseline value from the initiation of spinal anesthesia until fetal delivery.
Intervention: Alpha-Agonist (Drug)
Intensive group
The maternal systolic blood pressure was consistently maintained above 90% of the preoperative baseline value from the initiation of spinal anesthesia until fetal delivery.
Intervention: α-adrenergic receptor agonist (Drug)
Outcomes
Primary Outcomes
ED50 and ED90
Time Frame: 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 Outcomes
- The incidence of bradycardia.(1-15 minutes after spinal anesthesia)
- The incidence of post-spinal anesthesia hypotension(1-15 minutes after spinal anesthesia)
- The incidence of severe post-spinal anesthesia hypotension.(1-15 minutes after spinal anesthesia)
- APGAR score(5 min after delivery)
- The incidence of hypertension.(1-15 minutes after spinal anesthesia)
- pH(Immediately after delivery)
- Base excess(Immediately after delivery)
- Partial pressure of oxygen (PO2)(Immediately after delivery)
- The incidence of nausea and vomiting.(1-15 minutes after spinal anesthesia)