NCT06151522

90% Effective Dose of Phenylephrine Infusions Under Intensive and Standard Treatment

90% Effective Dose of Phenylephrine Infusions for Preventing Postspinal Anesthesia Hypotension Under Intensive and Standard Treatment During Cesarean Section

• Status: Unknown
• Phase: N/A
• Study type: Interventional
• Enrollment: 80 (estimated)
• Sponsor: General Hospital of Ningxia Medical University · Academic / Other
• Sex: Female
• Age: 18 Years – 45 Years
• Healthy volunteers: Not accepted

Summary

The objective of this study is to investigate the 90% effective dose of phenylephrine 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 phenylephrine infusions for preventing postspinal anesthesia hypotension under intensive and standard treatment during cesarean section.

Conditions

• Adverse Effect

Interventions

Type	Name	Description
DRUG	Alpha-Agonist	An initial infusion dose of prophylactic phenylephrine (0.625 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.125 ug/kg/min of prophylactic phenylephrine according to the responses of previous patients according to the up-down sequential allocation.
DRUG	α-adrenergic receptor agonist	An initial infusion dose of prophylactic phenylephrine (0.625 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.125 ug/kg/min of prophylactic phenylephrine according to the responses of previous patients according to the up-down sequential allocation.

Timeline

• Start date: 2025-04-01
• Primary completion: 2025-06-30
• Completion: 2025-06-30
• First posted: 2023-11-30
• Last updated: 2023-11-30