Effect of Timing on Efficacy of Morphine Analgesia After 2-chloroprocaine Anesthesia

Labor Clinical Trial

Official title:

Interaction Between Epidural 2-chloroprocaine and Epidural Morphine: Effect of Timing on Efficacy of Morphine Analgesia After 2-chloroprocaine Anesthesia

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00487084
• Other study ID #: 0524-021
• Status: Completed
• Phase: N/A
• First received: June 13, 2007
• Last updated: March 17, 2014
• Start date: August 2004
• Est. completion date: September 2008

Study information

• Verified date: March 2014
• Source: Northwestern University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

Epidural chloroprocaine is often used in obstetrical anesthesia because of its fast onset and short duration. These properties make it an ideal drug to use for epidural anesthesia in patients undergoing postpartum tubal ligation. When epidural morphine is given after chloroprocaine, there is a decreased efficacy of analgesia as compared to lidocaine (1). Several studies have hypothesized a specific opioid receptor mediated antagonism of chloroprocaine (2,3). Karambelkar raised the question whether this decreased efficacy is due to a disparity between the time the chloroprocaine anesthesia resolves and the onset of epidural morphine analgesia, resulting in a time window of pain (2). The duration of action of epidural 2-CP anesthesia is 30-45 minutes and the onset of epidural morphine analgesia is 60-70 minutes, therefore the regression of sensory blockade before the onset of the morphine analgesia could result in a window of pain (2). Hess and colleagues studied epidural morphine analgesia and women who had a Cesarean delivery under spinal bupivacaine anesthesia (3). Subjects were randomized to receive epidural 2-CP and morphine or epidural saline and morphine. There was no difference in postoperative analgesia between the two groups (3 and personal communication, Dr. Philip Hess). A literature search cross referencing epidural chloroprocaine, using Pub Med, did not produce any articles comparing epidural morphine given before the procedure (in an attempt to time the onset of analgesia with the resolution of chloroprocaine anesthesia) to the standard administration time after the procedure.

Description:

Women undergoing post partum tubal ligation with an epidural in-situ will be randomly double blindedly selected into one of three groups for pain control. The groups are epidural 1) epidural morphine-chloroprocaine 2) epidural chloroprocaine-morphine 3) epidural morphine-lidocaine. Groups 1 and 3 will receive morphine 30 minutes prior to local anesthetic dosing followed by saline placebo after local dosing. Group 2 will receive placebo 30 minutes prior to local anesthetic dosing followed by epidural morphine. Pain scores and supplemental analgesic requirements will be evaluated 30 minutes, 1hr, 2hr, 4hr and every 4 hrs for the first 24hrs.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 136
• Est. completion date: September 2008
• Est. primary completion date: September 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• All patients with an epidural catheter in situ for labor analgesia, status post a vaginal delivery, and scheduled for a postpartum tubal ligation under epidural anesthesia will be eligible

Exclusion Criteria:

• Allergy/hypersensitivity to morphine

• Allergy/hypersensitivity to ester-linked local anesthetics or para-amino benzoic acid (PABA)

• Body Mass Index >40 kg/m2

• Patients using chronic opioids

• History of obstructive sleep apnea

• Any contraindication to epidural anesthesia

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Analgesia, Epidural
• Labor

Intervention

Drug:
• Morphine-CP-saline (MCS)
3mg of preservative free morphine will be administered epidurally 30 min prior to epidural anesthesia. Epidural 3% 2CP will be used to achieve a T4 dermatomal level for surgical anesthesia for PPTL. 6ml of epidural saline will be administered at skin incision
• saline-2CP-morphine (SCM)
6ml of saline will be administered epidurally 30 min prior to epidural anesthesia. Epidural 3% 2CP will be used to achieve a T4 dermatomal level for surgical anesthesia for PPTL. 3mg of preservative free morphine will be administered at skin incision
• saline-lidocaine-morphine (SLM)
3mg of preservative free morphine will be administered epidurally 30 min prior to epidural anesthesia. Epidural 2% lidocaine with epinephrine 1:200,000 will be used to achieve a T4 dermatomal level for surgical anesthesia for PPTL. 6ml of epidural saline will be administered at skin incision

Locations

Country	Name	City	State
United States	Northwestern University	Chicago	Illinois

Sponsors (1)

Lead Sponsor	Collaborator
Northwestern University

Country where clinical trial is conducted

United States, 

References & Publications (3)

Camann WR, Hartigan PM, Gilbertson LI, Johnson MD, Datta S. Chloroprocaine antagonism of epidural opioid analgesia: a receptor-specific phenomenon? Anesthesiology. 1990 Nov;73(5):860-3. — View Citation

Eisenach JC, Schlairet TJ, Dobson CE 2nd, Hood DH. Effect of prior anesthetic solution on epidural morphine analgesia. Anesth Analg. 1991 Aug;73(2):119-23. — View Citation

Karambelkar DJ, Ramanathan S. 2-Chloroprocaine antagonism of epidural morphine analgesia. Acta Anaesthesiol Scand. 1997 Jun;41(6):774-8. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Duration of Continuing Analgesia	Time to first request for supplemental analgesia	48 hours	No
Primary	Supplemental Analgesia in First 90 Minutes	Participants requesting supplemental analgesia in the first 90 minutes following study drug	90 min	No
Secondary	Verbal Rating Score (0 to 10) for Pain (VRPS)	Verbal Rating Pain Score (VRPS) at time of post-anesthesia recovery room entry, where 0 = no pain and 10 = worst pain imaginable	At recovery room entry	No
Secondary	Supplemental Analgesia in First 48 Hours	Participants requesting supplemental analgesia in first 48 hours	48 hours	No