Variable Rate Phenylephrine Infusion for Prevention of Spinal-induced Hypotension for Cesarean Delivery

NCT01378325 | Completed Phase 4 Results DMC

• 1 other identifier: ANES.SS.10
• Study Type: interventional
• Target: 80
• Locations: 0 countries
• Sites: N/A

Brief Summary

Rapid administration of crystalloid immediately after induction of spinal anesthesia (coload) to be more effective in terms of managing hypotension as compared to administering crystalloid before spinal anesthesia (preload). Phenylehrine infusion is a safe and effective way to reduce incidence and frequency of hypotension during SA for cesarean delivery. Hypotension was virtually eliminated by use of high-dose prophylactic phenylephrine infusion at a rate of 100 µg/min and rapid crystalloid coload up to two liters (administration at the time of SA). However, incidence of reactive hypertension was frequent up to 47% with decrease in maternal heart rate (HR). This may raise concern in patients in whom increase of blood pressure may be detrimental, like chronic hypertension and in the presence of a compromised uteroplacental blood flow. A recent study found that infusing phenylephrine at a fixed rate of 75 and 100 ug/min is associated with more episodes of hypertension than placebo or the lower infusion rates of 25 and 50 ug/min respectively. However, there was no reduction in the number of physician interventions (phenylephrine boluses and stopping the infusion) needed to maintain maternal systolic blood pressure within 20% of baseline among all groups. Prophylactic fixed rate infusions may have limited application in clinical practice, and a variable rate (i.e. modifying the rate according to hemodynamics) has been advocated. The bolus administration of phenylephrine to treat hypotension is still commonly used, but requests multiple interventions from the anesthesiologists and is time consuming. Eighty patients scheduled for cesarean delivery under spinal anesthesia will be assigned to one of two groups. Immediately after spinal injection, rapid crystalloid colaod of lactated Ringer of 15 mL/kg over a period of 10-15 min will be initiated. Patients in Group I will receive infusion of normal saline (placebo) and patients in group II variable infusion rate of phenylephrine started at 0.75 ug/kg (close to the dose of 50 ug/min recommended for fixed infusion rate). The number of interventions needed to maintain maternal systolic blood pressure within 20% of baseline, hemodynamic performance, intraoperative nausea and vomiting, and umbilical cord blood gases will be compared between the two groups. We will define a reliable and safe method to ensure maternal hemodynamic stability during spinal anesthesia for cesarean delivery with the least physician interference.

Conditions

Anesthetic Complication Spinal

Keywords

spinal; cesarean delivery; phenylephrine; hypotension

Outcome Measures

Primary Outcomes (1)

• Number of Physician Interventions Needed to Maintain Maternal Blood Pressure After Spinal Anesthesia Within 20% of Baseline and to Treat Bradycardia During Cesarean Delivery.

  Physician interventions are triggered by hemodynamic changes more than 20% of baseline. The intervention can be one or more of the following: * stopping the phenylephrine infusion * changing the rate of phenylephrine infusion * rescue intravenous bolus of phenylephrine (100 µg) for hypotension * rescue intravenous bolus of atropine (0.4 mg) for bradycardia

  Patients will be followed up throughout the Cesarean delivery (average of 1.5 hours).

Study Arms (2)

Phenylephrine

EXPERIMENTAL

PHenylephrine infusion started at 0.75 microgram per kg per mL started at spinal injection till delivery

Drug: Phenylephrine

Saline

PLACEBO COMPARATOR

Prophylactic variable rate of saline infusion where we adjusted the pump at a starting rate of 0.75 µg/kg/min, equivalent to 0.0075 mL/kg/min of saline

Drug: saline

Interventions

Phenylephrine DRUG

Prophylactic variable rate of phenylephrine infusion started at 0.75 µg/kg/min vs saline

Also known as: Neosynephrine

Phenylephrine

saline DRUG

Prophylactic variable rate of saline infusion where we adjusted the pump at a starting rate of 0.75 µg/kg/min, equivalent to 0.0075 mL/kg/min of saline

Saline

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Parturients beyond 37 weeks gestation
• ASA І or ІІ

You may not qualify if:

• pregnancy-induced hypertension
• chronic hypertension
• multiple pregnancy
• fetal compromise
• diabetes mellitus
• polyhydramnios
• body weight \>100 kg
• major systemic disease
• anemia (hemoglobin concentration\<10 g/dl)
• clotting diathesis

Sponsors & Collaborators

• American University of Beirut Medical Center: lead

MeSH Terms

Conditions

Hypotension

Interventions

Phenylephrine; Sodium Chloride

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Ethanolamines; Amino Alcohols; Alcohols; Organic Chemicals; Amines; Chlorides; Hydrochloric Acid; Chlorine Compounds; Inorganic Chemicals; Sodium Compounds

Results Point of Contact

• Title: Sahar Siddik-Sayyid
• Organization: AUBMC

ss01@aub.edu.lb

9611350000

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: anesthesia

Study Record Dates

• First Submitted: June 10, 2011
• First Posted: June 22, 2011
• Study Start: July 1, 2012
• Primary Completion: January 1, 2013
• Study Completion: January 1, 2013
• Last Updated: August 26, 2014
• Results First Posted: August 26, 2014

Record last verified: 2014-08