title: A randomised, double-blind, placebo-controlled study to assess the safety and efficacy of methoxyflurane for procedural pain of a bone marrow biopsy.
abstract: BACKGROUND
  Pain during bone marrow biopsy (BMB) under local anaesthesia (LA) is reported in 70% of patients, of whom 35% rate the pain as severe. Pain is experienced during both the biopsy and the marrow aspiration. Many medical centres use conscious sedation involving benzodiazepines and/or opioids administered orally or intravenously for BMB analgesia. Methoxyflurane (MEOF) is self-administered by a handheld device (the Penthrox inhaler), which is licensed in Australia for the relief of pain associated with short surgical procedures.
  
  
  OBJECTIVE
  To evaluate the efficacy and safety of MEOF analgesia in patients with cancer undergoing BMB.
  
  
  METHODS
  Patients received LA plus either MEOF or placebo. The primary endpoint was worst pain intensity measured with the Numerical Rating Scale. Anxiety was assessed with the State Trait Anxiety Inventory (STAI-Y-1). Patients, operators and the research nurse rated global medication performance using a 5-point Likert scale.
  
  
  RESULTS
  Forty-nine of the 50 patients randomised to MEOF and 48 of the 50 patients randomised to placebo effectively received the allocated intervention. Mean±SD worst pain overall was 4.90±2.07 in MEOF group and 6.0±2.24 in placebo group (p=0.011). Worst pain during the aspiration was 3.3±2.0 in MEOF group and 5.0±2.4 in placebo group (p<0.001). 49% of patients treated with MEOF rated the medication as very good or excellent compared with 16.5% of the patients treated with placebo (p=0.005). 20.4% of patients treated with MEOF had an adverse event (AE) compared with 4.2% in the placebo arm (p=0.028). All AEs were grade 1.
  
  
  CONCLUSIONS
  MEOF was safe and performed better than placebo for analgesia in BMB procedures.
authors.affiliation: Department of Pain and Palliative Care, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors.forename: Odette
authors.initials: O
authors.lastname: Spruyt
authors.affiliation: Department of Haematology, Peter MacCallum Cancer Centre/University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Westerman
authors.affiliation: Centre for Biostatistics & Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors.forename: Alvin
authors.initials: A
authors.lastname: Milner
authors.affiliation: Centre for Biostatistics & Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors.forename: Mathias
authors.initials: M
authors.lastname: Bressel
authors.affiliation: Palliative Medicine, Davidoff Cancer Centre, Rabin Medical Centre, Petah-Tikva, Israel.
authors.forename: Simon
authors.initials: S
authors.lastname: Wein
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001315:Australia; D001706:Biopsy / Q000009:adverse effects; D001853:Bone Marrow / Q000473:pathology*; D001856:Bone Marrow Examination; D016292:Procedural Sedation; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008733:Methoxyflurane / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement
chemical_list: D000701:Analgesics, Opioid; D018685:Anesthetics, Inhalation; D008733:Methoxyflurane
keywords: Procedural pain; bone marrow biopsy; cancer-related pain; methoxyflurane