title: A pilot randomized study comparing two methods of non-invasive ventilation withdrawal after acute respiratory failure in chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  Patients with chronic obstructive pulmonary disease (COPD) presenting with acute hypercapnic respiratory failure (AHcRF) benefit from non-invasive ventilation (NIV). The best way to withdraw NIV is not known, and we conducted a pilot study comparing stepwise versus immediate withdrawal of NIV in these patients.
  
  
  METHODS
  This was a prospective, single-centre, open-labelled randomized study comparing stepwise versus immediate withdrawal of NIV in patients with COPD exacerbation recovering from AHcRF. The primary end-point was the success rate of NIV withdrawal, defined as no restarting of NIV from randomization to 48 h after complete withdrawal of NIV.
  
  
  RESULTS
  Sixty patients were randomized, 35 patients to stepwise withdrawal and 25 patients to immediate withdrawal. The two study arms were clinically comparable. There was no statistically significant difference in the success rate, with NIV successfully stopped in 74.3% and 56% in the stepwise and immediate withdrawal groups, respectively (P = 0.139).
  
  
  CONCLUSIONS
  We could not show any benefits for either strategy to withdraw NIV. The study may have been underpowered to detect differences, and larger prospective studies are required.
authors.affiliation: Division of Respiratory Medicine, Department of Medicine, United Christian Hospital, Hong Kong SAR, China.
authors.forename: Chung-Tat
authors.initials: CT
authors.lastname: Lun
authors.forename: Veronica L
authors.initials: VL
authors.lastname: Chan
authors.forename: Wah-Shing
authors.initials: WS
authors.lastname: Leung
authors.forename: Alice P S
authors.initials: AP
authors.lastname: Cheung
authors.forename: Suet-Lai
authors.initials: SL
authors.lastname: Cheng
authors.forename: Miranda S N
authors.initials: MS
authors.lastname: Tsui
authors.forename: Chung-Ming
authors.initials: CM
authors.lastname: Chu
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation / Q000379:methods*; D017063:Outcome Assessment, Health Care; D010865:Pilot Projects; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications*; D012008:Recurrence; D012131:Respiratory Insufficiency / Q000209:etiology* / Q000628:therapy*; D013997:Time Factors; D028761:Withholding Treatment