Low-positive pressure ventilation improves non-hypoxaemic apnoea tolerance during ear, nose and throat pan-endoscopy: A randomised controlled trial

The objective was to determine whether or not pre-oxygenation with PSV increases the duration of non-hypoxaemic apnoea in non-obese patients during pan-endoscopy. DESIGN: A randomised, controlled trial. SETTING: Amiens University Hospital, France. PATIENTS: Fifty patients scheduled for ENT pan-endoscopy with a BMI lower than 35 kg m−2. INTERVENTION: Patients scheduled for pan-endoscopy were enrolled to receive either 100% oxygen at neutral pressure (the control group) or 100% oxygen with positive-pressure ventilation (a positive inspiratory pressure of 4 cmH2O and a positive end-expiratory pressure of 4 cmH2O; the PSV group) during spontaneous ventilation with a face mask. The goal of pre-oxygenation was to obtain an end-tidal oxygen concentration of more than 90% prior to induction of anaesthesia. MAIN OUTCOME MEASURES: The primary efficacy criterion was the duration of non-hypoxaemic apnoea (i.e. before the peripheral capillary oxygen saturation fell to 90%). Secondary outcomes were duration of pre-oxygenation, pre-oxygenation failure and tolerance. RESULTS: The mean (interquartile range) duration of non-hypoxaemic apnoea was longer in the PSV group [598 (447 to 717) s] than in the control group [310 (217 to 451) s] (P 
Source: European Journal of Anaesthesiology - Category: Anesthesiology Tags: Ventilation Source Type: research