None listed
Conditions
Brief summary
The main aim is to investigate the efficacy and safety of methoxyflurane as a patient controlled analgesia in colonoscopic procedures, as compared to the traditional endoscopist provided analgesia/sedation. Hypothesis Methoxyflurane is as effective and safe in providing adequate analgesia for patients undergoing colonoscopic procedures as conventional intravenous sedative/analgesia with midazolam and fentanyl. Patients prefer patient controlled analgesia, compared with endoscopist administered analgesia.
Interventions
Those randomised to the methoxyflurane arm will be given extra instructions on the use of the Penthrox inhaler. They will then be asked to inhale the methoxyflurane for approximately 2 minutes as a pre-medication from one, 3mL dose in a Penthrox inhaler. Since methoxyflurane has a sweet tasting smell, patients will be advised to breathe in a stepwise fashion (from shallow to deep) over that 2 minute period. Once the colonoscopy has commenced, patients will be encouraged to take an adequate inhal
Those randomised to the methoxyflurane arm will be given extra instructions on the use of the Penthrox inhaler. They will then be asked to inhale the methoxyflurane for approximately 2 minutes as a pre-medication from one, 3mL dose in a Penthrox inhaler. Since methoxyflurane has a sweet tasting smell, patients will be advised to breathe in a stepwise fashion (from shallow to deep) over that 2 minute period. Once the colonoscopy has commenced, patients will be encouraged to take an adequate inhalation of methoxyflurane to provide sufficient analgesia. Patients are then allowed to self administer as much methoxyflurane as they feel they require within the safety limit as recommended by the manufacturer (6mL /day). Furthermore, they will be instructed to self administer further doses of methoxyflurane by the endoscopist if the endoscopist anticipate potential loops which may cause discomfort.
Sponsors
Dr. Nam Q Nguyen
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
Able to give informed consent Adequate understanding of use of the Penthrox inhaler
Exclusion criteria
History of significant alcohol (>40gms/d for males, 20gms/d for females) or narcotic use. Previous history of significant cardiac or respiratory illnesses (ie. ischaemic heart disease, chronic obstructive pulmonary disease). Significantly underweight (<45kg) Significant smoking history of more than 20 packs / year. Previous history of gastrointestinal surgery (likely to increase difficulty of colonoscopy) Renal impairment Diabetes Mellitus Previous possible allergy to the medication by the patient or a relative Hypersensitivity to fluorinated agents Previous head injury Difficulty in following instructions (including language barrier) Patients taking any potential nephrotoxic drugs (e.g. aminoglycosides) Personal or a family history of malignant hyperthermia. Patients without English literacy
Outcome results
None listed