Efficacy of Inhaled Methoxyflurane (Penthrox) as Adjunct for Urologic Procedures Under Local Anesthetic: A Pilot Study

NCT ID: NCT07192198

Last Updated: 2025-09-25

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE2
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-04-17
• Study Completion Date: 2024-12-19

Brief Summary

We wish to perform a prospective randomized controlled pilot study at the Men's Health Clinic and Health Science's Centre to assess whether or not the use of Penthrox as an adjunct to LA is associated with improved pain tolerance and anxiety levels than local anesthetic alone

Detailed Description

This non-blinded, randomized controlled trial is to be conducted at both the Men's Health Clinic and Health Sciences Centre in Winnipeg, Manitoba. All eligible patients between the ages of 18-65, undergoing andrology and male infertility under local anesthetic or select endourology procedures under loco-sedation, will be invited to participate in the study. Patients will be excluded if; history of substance use disorder, history renal impairment, history of liver dysfunction, previous hypersensitivity to Penthrox or related agents, personal or family history of malignant hypothermia. They will be randomly assigned in a 1:1 ratio using a computer-generated random list. For penoscrotal cases, patient will be randomized to Penthrox + local infiltration of 50/50 lidocaine and bupivacaine mixture vs local infiltration alone. For select endourology procedures, patients will be randomized to Penthrox + topical local anesthetic vs IV sedation + topical anesthetic. Participants may begin using the Penthrox 10 minutes prior to procedure start given its median time of onset of 5 minutes. In the post-operative recovery area, patient will be asked to complete a questionnaire related to pain and anxiety of procedure.

Baseline characteristics such as age, use of analgesics, prior history of procedure under loco-sedation, history of chronic pain, baseline pain level (Brief Pain Inventory), pre-procedural anxiety (State Trait Anxiety Inventory) will be collected.

Conditions

Scrotum Disease; Hydrocele Male; Spermatocele; Scrotal Hematocele; Anesthesia, Local

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Intervention arm-Penthrox

Participants can begin using penthrox 10 minutes prior to procedure start, given its median onset time of 5 minutes

Group Type: EXPERIMENTAL

Methoxyflurane

Intervention Type: DRUG

Penthrox is a brand name for a drug called methoxyflurane. It is an inhaled analgesic (pain-relieving) agent used primarily for the relief of moderate to severe pain, typically in emergency medical situations or during minor medical procedures. Penthrox is administered by inhaling the vapors through a hand-held inhaler device. It acts quickly to provide pain relief and has a relatively short duration of action.

Control arm

Patients in the control arm will only receive local infiltration.

Group Type: PLACEBO_COMPARATOR

Control

Intervention Type: OTHER

This intervention will be the control group, only receiving local infiltration.

Interventions

Methoxyflurane

Penthrox is a brand name for a drug called methoxyflurane. It is an inhaled analgesic (pain-relieving) agent used primarily for the relief of moderate to severe pain, typically in emergency medical situations or during minor medical procedures. Penthrox is administered by inhaling the vapors through a hand-held inhaler device. It acts quickly to provide pain relief and has a relatively short duration of action.

Intervention Type: DRUG

Control

This intervention will be the control group, only receiving local infiltration.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Adult patients undergoing hydrocelectomy, spermatocelectomy, epididymectomy, testicular biopsy, scrotal lesion or cyst excision under local anesthesia alone will be included.

Exclusion Criteria

• Patients will be excluded if their procedure was to be performed with sedatives (e.g., inhaled nitrous oxide gas, oral, or IV sedation) or did not provide consent to be randomized

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

University of Manitoba

OTHER

Sponsor Role: lead

Responsible Party

Premal Patel, MD

Assistant Professor, Department of Surgery. Director, Undergraduate Urologic Medical Education

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Men's Health Clinic

Winnipeg, Manitoba, Canada

Countries

Canada

Other Identifiers

HS26348

Identifier Type: -

Identifier Source: org_study_id