Preoxygenation in Obese Patients: High-Flow Nasal Cannula Oxygen Versus Non-Invasive Ventilation: A Randomised Controlled Study. The PREOPTIPOP Study

Abstract

Background: Non-invasive ventilation (NIV) is the gold standard for preoxygenation in obese patients. In this population, high-flow nasal cannulae (HFNC) before and during intubation extends apnoea time without desaturation, possibly through apnoeic oxygenation. No randomised study comparing HFNC with NIV is available. Methods: The PREOPTIPOP study is a randomised, single-centre, open-labelled, controlled trial including obese patients requiring intubation before scheduled surgery. Patients were randomised to receive preoxygenation by HFNC or NIV. HFNC was maintained throughout intubation whereas NIV was removed to perform laryngoscopy. The study was designed to assess the superiority of HNFC. The primary outcome was the lowest level of end-tidal oxygen concentration (EtO2) within two minutes after intubation. Secondary outcomes included drop in pulse oximetry and complications related to intubation. Main findings: A total of 100 patients were randomised. The intent-to-treat analysis found median [IQR] lowest EtO2 of 76% [66-82] for HFNC and 88% [82-90] for NIV (mean difference -12·1 [-15·1 to -8·5], p<0·0001). Mild desaturation below 95% was more frequent with HFNC (30%) than with NIV (12%) (relative risk 2·5, IC 95% [1·1 to 5·9], p=0·03) and median lowest SpO2 during intubation was 98% [93-99] in HFNC vs. 99% [97-100] in NIV (p=0·03). Severe and moderate complications were not different but patients reported more discomfort with NIV (28%) vs. HFNC (4%), p=0·001. Interpretation: Compared with the gold standard, preoxygenation with HFNC in obese patients provided lower EtO2 after intubation and a higher rate of desaturation <95%. Trial Registration Number: Clinicaltrials.gov NCT03106441 Funding: Institutional funding, additional grant from Fisher & Paykel Declaration of Interest: Fanny Feuillet, Claire Blanchard, Eric Miraille and Christophe Guitton declare no conflict of interest. Mickael Vourc’h declares personal fees from MSD, Pfizer, Baxter and grants from Fischer Paykel, outside the submitted work. Samir Jaber reports personal fees from Draeger, Fresenius-Xenios and Fisher Paykel Healthcare, outside the submitted work. Karim Asehnoune declares personal fees from Fisher Paykel Healthcare, Baxter, LFB, Fresenius. Ethical Approval: The study was approved by the institutional review board (CPP Nord-Ouest I, registration number 019/2017). The study was conducted in accordance with the Declaration of Helsinki and was registered before the first inclusion (NCT03106441).