Non-Invasive Positive airway Pressure thErapy to Reduce Postoperative Lung complications following Upper abdominal Surgery (NIPPER PLUS): a pilot randomised control trial.

OBJECTIVES: Postoperative pulmonary complications (PPCs) are a common serious complication following upper abdominal surgery. Postoperatively, physiotherapy-led non-invasive ventilation (NIV) may be a promising method to reduce PPC incidence. The objectives of this pilot trial were to examine preliminary effectiveness, feasibility and safety of additional intermittent physiotherapy-led NIV compared to continuous high-flow nasal cannula oxygen therapy (HFNC) alone. DESIGN: Single-centre, assessor-blinded, parallel-group, pilot randomised control trial. SETTING: Primary-referral hospital in Australia. PARTICIPANTS: 130 high-risk patients undergoing upper abdominal surgery. INTERVENTIONS: Continuous HFNC for 48-hours following surgical extubation, or HFNC plus five 30-minute physiotherapy-led NIV sessions. OUTCOMES: PPC incidence, trial feasibility and safety. RESULTS: PPC incidence was similar between groups (HFNC alone 12/65 (18%) vs HFNC plus NIV 10/64 (16%) adjusted HR 0.95; 95% CI 0.40-2.29). Delivery of HFNC as per-protocol was achieved in 81% (n = 105) of all participants. Physiotherapy-led NIV initiated within four-hours of surgical extubation was achieved in 81% (n = 52) of intervention group participants, with a mean 4.2 (SD 1.3) total number of NIV sessions delivered in the first two postoperative days. NIV was delivered as per-protocol in 52% of this cohort. Two episodes of severe hypotension during NIV requiring medical intervention were reported. CONCLUSION: Delivery of continuous HFNC was feasible. Delivery of NIV within four-hours of extubation was achieved and delivered safely with< 1% adverse events. The planned NIV intervention of five sessions within two postoperative days was not feasible. The results of this pilot study have informed the decision not to proceed to a fully powered trial. CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, www.anzctr.org.au ACTRN12617000269336. CONTRIBUTION OF THE PAPER.