Use of Nitrous Oxide for Pain Alleviation in Women Undergoing Osmotic Dilator Insertion for Dilatation and Evacuation

NCT ID: NCT05579288

Last Updated: 2022-10-13

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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

Recruitment Status

UNKNOWN

Clinical Phase

EARLY_PHASE1

Total Enrollment

60 participants

Study Classification

INTERVENTIONAL

Study Start Date

2022-12-31

Study Completion Date

2024-12-31

Brief Summary

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

A randomised control study aiming to examine whether inhaled N2O/O2 during cervical preparation for second trimester dilatation and evacuation with osmotic dilators (laminaria) alleviates pain and is superior to placebo.

Detailed Description

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

Introduction:

Women undergoing second trimester abortion often undergo preparation of the cervix prior to the Dilatation and Evacuation (D\&E). Women may undergo preparation with osmotic dilators (laminaria) or prostaglandins, both methods are effective and safe for cervical preparation(1). In our institution, the protocol for cervical preparation in the second trimester with osmotic dilator insertion takes place 24 hours before the procedure in the gynecologic emergency room/clinic. Currently, the protocol does not include any method of pain relief during the cervix preparation procedure.

At this time, besides general anesthesia, there are no satisfactory evidence-based methods for pain alleviation for osmotic dilators insertion. For example, a recent randomized controlled trial showed topical application of lidocaine spray to the cervix before insertion did not result in lower reported pain as compared with placebo(2).

Inhaled nitrous oxide administered with oxygen (N2O/O2) is an acceptable, effective and widely used method for pain relief in short painful pediatric ,dental and urologic procedures(3-5), as well as in the labor room and in the emergency room(6, 7). N2O/O2 has analgesic, anxiolytic and amnestic properties. N2O/O2 has rapid onset and reversal with minimal side effects and few contraindications. Side effects of N2O/O2 are relatively minor and include nausea, dizziness, drowsiness, light-headedness, and diaphoresis. Contraindications include congenital heart defects, pulmonary hypertension, megaloblastic anemia and relatively low blood O2 saturation (\<95%)(8, 9).

A recent randomized controlled trial showed inhaled N2O/O2 is associated with less pain compared to oral sedation for pain management during in-office hysteroscopic sterilization(9) To the best of our knowledge, there is no literature regarding the efficacy of use of nitrous oxide for pain alleviation in women undergoing osmotic dilator insertion for second trimester Dilatation and Evacuation.

Goal:

To examine whether inhaled N2O/O2 during cervical preparation for second trimester dilatation and evacuation alleviates pain and is superior to placebo.

Methods:

A prospective randomized placebo-controlled trial consisting of two groups:

Inhaled N2O/O2 (group 1) Placebo group (O2 only) (group 2)

Women undergoing dilatation and evacuation in the second trimester and are about to undergo cervical dilatation with osmotic dilators (laminaria) will be invited to participate in a randomized placebo control trial comparing Inhaled N2O/O2 or placebo (O2 only).

The recruitment and trial will take place in the emergency room/clinic where the women come a day before the D\&E for cervical preparation. This procedure is routinely performed in a gynecologic chair without any sedation thus assessing pain scores is possible.

Informed consent will be obtained from each participant. Randomization will be performed using a computer randomization generator. After enrollment, patients will be randomized into one of the two study arms. allocation to the two treatment groups will be concealed in sequentially numbered opaque envelopes that will be opened only by the nurse actually administering the gas (either inhaled N2O/O2 or inhaled oxygen). The participant and physician will be completely blinded to the intervention.

Participants will be asked about their most severe pain during menses and asked to rate it from 0 to 10.

The patient will be placed in the lithotomy position.

Group1: Patients will receive inhaled N2O/O2 (70% N2O and 30% O2). A sterile bivalve speculum will be placed. Laminaria will be inserted. Inhaled N2O/O2 will be stopped after speculum removal.

Group2: Patients will receive inhaled O2 (100% O2). A sterile bivalve speculum will be placed. Laminaria will be inserted. Inhaled O2 will be stopped after speculum removal.

Patients will receive inhaled O2 (100% O2) throughout the procedure until speculum removal.

Pain will be assessed at 7-time intervals using a visual analog pain scale 0 (no pain) to 100 (worst possible pain) - 1.Prior to mask application, 2. Before speculum insertion, 3. Immediately after speculum insertion, 4. Immediately after insertion of first laminaria, 5. Immediately after insertion of last laminaria, 6. After speculum removal (including actual VAS and recall of maximal VAS during the procedure), 7. Before the D\&E the next day.

Satisfaction with the procedure will be collected as well- overall satisfaction (0-100) and satisfaction with pain control (0-100).

Data regarding adverse events will be collected as well.

Primary outcome:

Self-report of pain score immediately following speculum removal.

Secondary outcome:

Self-report of maximal pain during the procedure.

The protocol will not be repeated if a participant is to return for further laminaria insertion.

Conditions

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

Pain Alleviation Dilatation and Evacuation Laminaria Placement Nitrous Oxide

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

Primary Study Purpose

TREATMENT

Blinding Strategy

DOUBLE

Participants Investigators

Study Groups

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

Study Arm

Patients will receive inhaled N2O/O2 (70% N2O and 30% O2). A sterile bivalve speculum will be placed. Laminaria will be inserted. Inhaled N2O/O2 will be stopped after speculum removal.

Group Type EXPERIMENTAL

Nitrous oxide (N2O/O2)

Intervention Type DRUG

Nitrous oxide (N2O/O2) for pain alleviation

Control Arm

Patients will receive inhaled O2 (100% O2). A sterile bivalve speculum will be placed. Laminaria will be inserted. Inhaled O2 will be stopped after speculum removal.

Patients will receive inhaled O2 (100% O2) throughout the procedure until speculum removal.

Group Type PLACEBO_COMPARATOR

Oxygen (O2)

Intervention Type DRUG

Oxygen (O2) as placebo for control group

Interventions

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

Nitrous oxide (N2O/O2)

Nitrous oxide (N2O/O2) for pain alleviation

Intervention Type DRUG

Oxygen (O2)

Oxygen (O2) as placebo for control group

Intervention Type DRUG

Eligibility Criteria

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

Inclusion Criteria

* Informed consent

Exclusion Criteria

* D\&E due to PPROM or infection.
* Known N2O allergy.
* Contraindication to N2O use - Congenital heart defects, pulmonary hypertension, megaloblastic anemia, O2 blood saturation \<95%
Minimum Eligible Age

16 Years

Maximum Eligible Age

55 Years

Eligible Sex

FEMALE

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Sheba Medical Center

OTHER_GOV

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Sheba Medical Center

Ramat Gan, , Israel

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Israel

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Shlomi Toussia-Cohen, MD

Role: CONTACT

+97235302772

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Shlomi Toussia-Cohen, MD

Role: primary

References

Explore related publications, articles, or registry entries linked to this study.

Newmann SJ, Dalve-Endres A, Diedrich JT, Steinauer JE, Meckstroth K, Drey EA. Cervical preparation for second trimester dilation and evacuation. Cochrane Database Syst Rev. 2010 Aug 4;(8):CD007310. doi: 10.1002/14651858.CD007310.pub2.

Reference Type BACKGROUND
PMID: 20687085 (View on PubMed)

Meyer R, Cahan T, Yagel I, Afek A, Derazne E, Bar-Shavit Y, Yuval Y, Admon D, Shina A. A double-blind randomized trial comparing lidocaine spray and placebo spray anesthesia prior to cervical laminaria insertion. Contraception. 2020 Nov;102(5):332-338. doi: 10.1016/j.contraception.2020.07.002. Epub 2020 Jul 8.

Reference Type BACKGROUND
PMID: 32652092 (View on PubMed)

Wood M. The safety and efficacy of intranasal midazolam sedation combined with inhalation sedation with nitrous oxide and oxygen in paediatric dental patients as an alternative to general anaesthesia. SAAD Dig. 2010 Jan;26:12-22.

Reference Type BACKGROUND
PMID: 20151606 (View on PubMed)

Burnweit C, Diana-Zerpa JA, Nahmad MH, Lankau CA, Weinberger M, Malvezzi L, Smith L, Shapiro T, Thayer K. Nitrous oxide analgesia for minor pediatric surgical procedures: an effective alternative to conscious sedation? J Pediatr Surg. 2004 Mar;39(3):495-9; discussion 495-9. doi: 10.1016/j.jpedsurg.2003.11.037.

Reference Type BACKGROUND
PMID: 15017577 (View on PubMed)

Young A, Ismail M, Papatsoris AG, Barua JM, Calleary JG, Masood J. Entonox(R) inhalation to reduce pain in common diagnostic and therapeutic outpatient urological procedures: a review of the evidence. Ann R Coll Surg Engl. 2012 Jan;94(1):8-11. doi: 10.1308/003588412X13171221499702.

Reference Type BACKGROUND
PMID: 22524905 (View on PubMed)

Broughton K, Clark AG, Ray AP. Nitrous Oxide for Labor Analgesia: What We Know to Date. Ochsner J. 2020 Winter;20(4):419-421. doi: 10.31486/toj.19.0102.

Reference Type BACKGROUND
PMID: 33408580 (View on PubMed)

Descamps MJ, Gwilym S, Weldon D, Holloway V. Prospective audit of emergency department transit times associated with entonox analgesia for reduction of the acute, traumatic dislocated shoulder. Accid Emerg Nurs. 2007 Oct;15(4):223-7. doi: 10.1016/j.aaen.2007.07.008. Epub 2007 Oct 29.

Reference Type BACKGROUND
PMID: 17911025 (View on PubMed)

O'Sullivan I, Benger J. Nitrous oxide in emergency medicine. Emerg Med J. 2003 May;20(3):214-7. doi: 10.1136/emj.20.3.214.

Reference Type BACKGROUND
PMID: 12748131 (View on PubMed)

Schneider EN, Riley R, Espey E, Mishra SI, Singh RH. Nitrous oxide for pain management during in-office hysteroscopic sterilization: a randomized controlled trial. Contraception. 2017 Mar;95(3):239-244. doi: 10.1016/j.contraception.2016.09.006. Epub 2016 Sep 9.

Reference Type BACKGROUND
PMID: 27621048 (View on PubMed)

Mercier RJ, Liberty A. Intrauterine lidocaine for pain control during laminaria insertion: a randomized controlled trial. Contraception. 2014 Dec;90(6):594-600. doi: 10.1016/j.contraception.2014.07.008. Epub 2014 Jul 23.

Reference Type BACKGROUND
PMID: 25139724 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

SHEBA-22-8935-ST-CTIL

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

12 Versus 20 mL PCB for D&E Cervical Prep
NCT03356145 COMPLETED PHASE4