Addition of Buprenorphine to Paracervical Block for Pain Control During Osmotic Dilator Insertion

Study Results

Results available

Outcome measurements, participant flow, baseline characteristics, and adverse events have been published for this study.

View full results

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

PHASE4

Total Enrollment

57 participants

Study Classification

INTERVENTIONAL

Study Start Date

2020-05-28

Study Completion Date

2021-05-04

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Cervical preparation with osmotic dilators is commonly used prior to dilation and evacuation (D\&E) procedures to decrease the risk of complications. Women have described the pain of osmotic dilator insertion as moderate to severe yet there have been few studies aimed at addressing pain during and after osmotic dilator insertion. In addition to the discomfort during insertion, pain after osmotic dilator insertion peaks at 2 hours post-insertion with use of a lidocaine paracervical block. One randomized trial found that use of a paracervical block with 1% buffered lidocaine decreased pain with osmotic dilator insertion compared to a sham block. There are adjunct treatments to optimize analgesia with local anesthetics at a variety of anatomic locations. Buprenorphine, a partial mu-opioid receptor agonist, has been found to increase the quality of the anesthetic at the time of administration and increase the duration of nerve block analgesia at several anatomic sites, though has never been studied as an adjunct in a paracervical block. This has been used extensively in orthopedic surgery with significant prolongation of the local anesthetic effect by almost threefold in some studies.

Primary Aim: To compare the mean pain score at the time of osmotic dilator insertion among women randomized to a 1% lidocaine and buprenorphine paracervical block compared to a 1% lidocaine paracervical block alone.

Secondary Aim: To compare the mean pain score 2 hours after osmotic dilator insertion among women randomized to a lidocaine and buprenorphine paracervical block compared to a lidocaine paracervical block alone.

The investigators hypothesize that in patients undergoing osmotic dilator insertion in preparation for dilation and evacuation, the addition of buprenorphine 0.15mg to a 1% lidocaine paracervical block will be associated with lower mean pain scores at time of osmotic dilator insertion compared to women who receive a 1% lidocaine paracervical block alone.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Comparing Effectiveness of CSE Versus DPE for Labor Analgesia

NCT05068661

Labor Pain

COMPLETED PHASE4

Paracervical Block Before Intrauterine Device (IUD) Insertion

NCT01207401

Pain Control for Intrauterine Device Insertions

COMPLETED NA

Continuous Erector Spinae Plane Blocks to Treat Postoperative Pain After Open Gynecologic Procedures Via a Low Transverse (Pfannenstiel) Incision

NCT05082155

Surgical Incision Pain, Postoperative Pain, Acute

WITHDRAWN PHASE4

Intra-operative Uterosacral Ligament Bupivacaine Injection During Minimally Invasive Hysterectomy

NCT04157075

Pain, Postoperative Opioid Use

COMPLETED EARLY_PHASE1

Pain Control for Intrauterine Device Placement Using Paracervical Block

NCT02219308

Pain Due to Intrauterine Contraceptive Device

COMPLETED NA

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Dilation and evacuation (D\&E) is the most common method of second trimester abortion in the United States. Cervical preparation prior to the procedure is essential in order to allow passage of operative instruments and pregnancy tissue safely through the cervix and to decrease the risk of complications. In the second trimester, cervical preparation is typically achieved with placement of osmotic dilators prior to the procedure. Women have described the pain of osmotic dilator insertion as moderate to severe yet there have been few studies aimed at addressing pain during osmotic dilator insertion. A lidocaine paracervical block is commonly used for pain control during other gynecologic procedures including procedures involving cervical dilation like dilation and curettage. One randomized controlled trial found that use of a paracervical block with 1% lidocaine decreased pain with osmotic dilator insertion compared to a sham block. Because the dilators slowly expand after insertion, there is continued discomfort for several hours after placement. Research has shown that pain after osmotic dilator insertion peaks at 2 hours post-insertion with use of a lidocaine paracervical block and a local anesthetic is not sufficient to provide lasting pain relief. Systemic medications, such as gabapentin and narcotic analgesics have been studied to treat post-insertional dilator pain, however these treatments have not been shown to be effective.

There are many adjunct treatments to optimize the duration of local analgesia from a peripheral nerve block. Buprenorphine, a partial mu-opioid receptor agonist, is a high potency, lipophilic opioid and has a high binding capacity for the mu-opioid receptor. Because of the high binding capacity, buprenorphine has the longest duration of action of all opioids. When administered perineurally in combination with a local anesthetic, buprenorphine has been found to drastically increase the duration of analgesia at several anatomic sites, including axillary and subclavian brachial plexus blocks and infragluteal sciatic nerve blocks. With the addition of buprenorphine at doses of 0.15 - 0.3mg, there is significant prolongation of the anesthetic sensory blockade up to three times the duration of the local anesthetic alone. The use of perineural buprenorphine is well established for postoperative analgesia. Buprenorphine itself also has local anesthetic properties. Buprenorphine blocks voltage gated sodium channels and inhibits C-fiber action potentials, thereby contributing to an analgesic effect. Buprenorphine not only prolongs the duration of local anesthetic effect but also improves the analgesic properties when administered in a perineural block.

The addition of buprenorphine to a perineural local anesthetic has not been studied in a paracervical block. This study will be the first trial to assess the efficacy of buprenorphine to provide analgesia for a gynecologic procedure. This medication has the additional benefit of providing long lasting pain relief for procedures that cause continued discomfort after the end of the procedure. The investigators hypothesize that the addition of 0.15mg of buprenorphine to a lidocaine paracervical block will improve pain during osmotic dilator insertion and provide continued pain relief several hours after osmotic dilator insertion. If this intervention proves to provide better pain control than a lidocaine paracervical block alone, it would be an intervention for women during a painful clinic procedure.

A total of 114 women undergoing D\&E who require cervical preparation with osmotic dilators will be randomized to one of two study groups: (1) paracervical block with 20mL of 1% buffered lidocaine or (2) paracervical block with 20mL of 1% buffered lidocaine plus 0.15mg of buprenorphine. Participants, clinicians performing the procedure, and study personnel administering questionnaires will be blinded to study assignment. Participants will rate their level of pain on an 11-point numeric rating scale (NRS) during the insertion of osmotic dilators and at several time points after insertion. The primary outcome is to compare the median pain score at the time of osmotic dilator insertion in women randomized to a 1% lidocaine and buprenorphine paracervical block compared to a 1% lidocaine paracervical block alone. Secondary outcomes are to compare the median pain score 2 hours after osmotic dilator insertion; to assess overall narcotic and ibuprofen use after osmotic dilator placement and before dilation and evacuation procedure; to assess opioid related side effects; and to determine patient satisfaction with pain control during and after osmotic dilator insertion.

Primary Hypothesis: The addition of buprenorphine 0.15mg to a paracervical block using 1% lidocaine will be associated with a lower median pain score on the NRS at time of osmotic dilator insertion compared to women who receive a lidocaine paracervical block alone.

Secondary Hypothesis: The addition of buprenorphine 0.15mg to a paracervical block using 1% lidocaine will be associated with a lower median pain score on the NRS 2 hours after osmotic dilator insertion compared to women who receive a lidocaine paracervical block alone.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Procedural Pain Buprenorphine Adjuvants, Anesthesia Dilation and Evacuation Analgesics

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

This is a randomized, placebo controlled trial with stratified block randomization based on vaginal parity (vaginally nulliparous versus vaginally multiparous). Vaginal parity may influence pain during osmotic dilator insertion and thus the participants will be evenly distributed between strata.

Primary Study Purpose

TREATMENT

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors

A clinician who will not be administering the paracervical block will open the designated sealed sequentially numbered opaque randomization envelope containing computer generated randomization code and prepare the designated paracervical block into two 10 mL syringes. The syringes used to prepare the medication will be identical between study groups and the solutions will appear visually identical. A different clinician blinded to the treatment group will perform the standardized procedure for osmotic dilator insertion.

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Buprenorphine 0.15mg + 1% lidocaine paracervical block

Paracervical block with 18mL of 1% lidocaine buffered with 2 mL 8.4% sodium bicarbonate plus 0.15mg of buprenorphine

Group Type EXPERIMENTAL

Buprenorphine 0.15 MG

Intervention Type DRUG

Buprenorphine 0.15mg solution will be added to a 20mL 1% buffered lidocaine solution (paracervical block) which will be administered in the paracervical space prior to osmotic dilator insertion.

1% lidocaine paracervical block

Paracervical block with 18 mL of 1% lidocaine buffered with 2 mL 8.4% sodium bicarbonate

Group Type PLACEBO_COMPARATOR

Lidocaine 1% Injectable Solution

Intervention Type DRUG

20mL of 1% buffered lidocaine solution (paracervical block) will be administered in the paracervical space prior to osmotic dilator insertion.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Buprenorphine 0.15 MG

Buprenorphine 0.15mg solution will be added to a 20mL 1% buffered lidocaine solution (paracervical block) which will be administered in the paracervical space prior to osmotic dilator insertion.

Intervention Type DRUG

Lidocaine 1% Injectable Solution

20mL of 1% buffered lidocaine solution (paracervical block) will be administered in the paracervical space prior to osmotic dilator insertion.

Intervention Type DRUG

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Gestational age 14 0/7 weeks to 23 6/7 weeks at time of osmotic dilator insertion
* Require cervical preparation with placement of osmotic dilators
* At least 18 years of age
* Fluent in English or Spanish

Exclusion Criteria

* Same day dilation and evacuation procedure
* Request for sedation during osmotic dilator insertion
* Liver disease
* Allergy to buprenorphine, lidocaine, or ibuprofen
* Narcotic or opioid medication use in the preceding 24 hours
* Use of recreational/illicit medications in the preceding 24 hours
* Currently incarcerated

Minimum Eligible Age

18 Years

Eligible Sex

FEMALE

Accepts Healthy Volunteers

No