Phenylephrine in Spinal Anesthesia in Preeclamptic Patients
|ClinicalTrials.gov Identifier: NCT00458003|
Recruitment Status : Completed
First Posted : April 9, 2007
Last Update Posted : February 2, 2017
Hypotension remains a common clinical problem after induction of spinal anesthesia for cesarean delivery. Maternal hypotension has been associated with considerable morbidity (maternal nausea and vomiting and fetal/neonatal acidemia). Traditionally, ephedrine has been the vasopressor of choice because of concerns about phenylephrine's potential adverse effect on uterine blood flow. This practice was based on animal studies which showed that ephedrine maintained cardiac output and uterine blood flow, while direct acting vasoconstrictors, e.g., phenylephrine, decreased uteroplacental perfusion. However, several recent studies have demonstrated that phenylephrine has similar efficacy to ephedrine for preventing and treating hypotension and may be associated with a lower incidence of fetal acidosis. All of these studies have been performed in healthy patients undergoing elective cesarean delivery.
Preeclampsia complicates 5-6% of all pregnancies and is a significant contributor to maternal and fetal morbidity and mortality. Many preeclamptic patients require cesarean delivery of the infant. These patients often have uteroplacental insufficiency. Given the potential for significant hypotension after spinal anesthesia and its effect on an already compromised fetus, prevention of (relative) hypotension in preeclamptic patients is important. Spinal anesthesia in preeclamptic patients has been shown to have no adverse neonatal outcomes as compared to epidural anesthesia when hypotension is treated adequately. Due to problems related to management of the difficult airway and coagulopathy, both of which are more common in preeclamptic women, spinal anesthesia may be the preferred regional anesthesia technique. Recent studies have demonstrated that preeclamptic patients may experience less hypotension after spinal anesthesia than their healthy counterparts. To our knowledge, phenylephrine for the treatment of spinal anesthesia-induced hypotension has not been studied in women with preeclampsia. The aim of our study is to compare intravenous infusion regimens of phenylephrine versus ephedrine for the treatment of spinal anesthesia induced hypotension in preeclamptic patients undergoing cesarean delivery. The primary outcome variable is umbilical artery pH.
|Condition or disease||Intervention/treatment||Phase|
|Preeclampsia Hypotension||Drug: Ephedrine Drug: Phenylephrine||Not Applicable|
Show Detailed Description
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||110 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Double (Participant, Investigator)|
|Official Title:||Phenylephrine Versus Ephedrine to Treat Spinal Anesthesia-Induced Hypotension in Preeclamptic Patients During Cesarean Delivery|
|Study Start Date :||July 2006|
|Actual Primary Completion Date :||December 2016|
|Actual Study Completion Date :||December 2016|
Subject will receive a phenylephrine infusion to prevent and to treat hypotension associated with spinal anesthesia
Phenylephrine concentration: 100 mcg/mL. The infusion will be initiated immediately after completion of the spinal injection at a rate of 1 mL/min and continued for a minimum of 2 min after which the infusion will be stopped, continued or increased based on the SBP each minute. After each SBP measurement the infusion will be stopped if SBP > 80% baseline, and the infusion will be continued or restarted if the SBP is approximately equal to 80% baseline. The infusion will be increased by 1 mL/min if the SBP < 80% baseline. Each time there is hypotension the patient will receive a 1 mL IV bolus of the study solution and the infusion will be increased by 1 mL/min until delivery.
Active Comparator: Ephedrine
Subject will receive an ephedrine infusion to prevent and to treat hypotension associated with spinal anesthesia
Ephedrine concentration: 8 mg/mL. The infusion will be initiated immediately after completion of the spinal injection at a rate of 1 mL/min and continued for a minimum of 2 min after which the infusion will be stopped, continued or increased based on the SBP each minute. After each SBP measurement the infusion will be stopped if SBP > 80% baseline, and the infusion will be continued or restarted if the SBP is approximately equal to 80% baseline. The infusion will be increased by 1 mL/min if the SBP < 80% baseline. Each time there is hypotension the patient will receive a 1 mL IV bolus of the study solution and the infusion will be increased by 1 mL/min until delivery.
- The umbilical artery pH in the phenylephrine group will be higher than in the ephedrine group, although the overall incidence of absolute fetal acidosis is not anticipated to be different between groups. [ Time Frame: Immediately after delivery ]
- Efficacy of study drug in preventing and treating hypotension associated with spinal anesthesia in women with preeclampsia [ Time Frame: During and immediately after study drug infusion ]
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00458003
|United States, Illinois|
|Northwestern Memorial Hospital|
|Chicago, Illinois, United States, 60611|
|Chicago, Illinois, United States, 60611|
|Principal Investigator:||Cynthia A. Wong, M.D.||Northwestern University|