Transtracheal jet oxygenation: Comparing the efficacy and safety of two self‐made Y‐connector devices with the ENK oxygen flow modulator™ in an infant animal model

Abstract

Self-made Y-connector jet-oxygenation devices with wide-bore expiratory port have been described but not evaluated in infant models. Little is known about the effect of oxygen flow rates on jet oxygenation via transtracheal cannula. The aim of this study was to compare two self-made Y-connector jet-oxygenation devices against the ENK oxygen flow modulator™, and the effects of three different oxygen flow rates based on body weight, in both unobstructed and obstructed airways, on the time to re-oxygenate in a rabbit infant model. The aim was also to assess the effectiveness of an oxygen flow rate of 1L/min, for re-oxygenation using ENK oxygen flow modulator™. Nine rabbits were grouped in threes: Group 1 had a Y-connector attached to an intravenous infusion tubing, Group 2 the same Y-connector attached to a perfusion oxygenator tubing and Group 3, ENK oxygen flow modulator™. From oxygen saturations of 75%, the rabbits were jet oxygenated using their assigned device for 10minutes at each flow rate of 1L/kg/min, 1.5L/kg/min and 2L/kg/min with their airways unobstructed and later, obstructed. Group 3 had additional experiments involving an absolute oxygen flow rate of 1L/min. All devices resulted in rapid re-oxygenation within 40seconds at flow rates of 1L/kg/min. Oxygen flow rates beyond 1L/kg/min in obstructed airways resulted in high airway pressures. All rabbits in Group 3 with obstructed airways died from barotrauma when jet oxygenated at a flow rate of 1.5L/kg/min. When an oxygen flow rate of 1L/min was used in Group 3, there was a failure to re-oxygenate to SpO2 90% within 120seconds in some rabbits. Our animal model results suggest that self-made Y-connector jet-oxygenation devices with wide-bore expiratory port are efficacious and perhaps safer than ENK oxygen flow modulator™ in obstructed airways, and jet oxygenation with minimal oxygen flow rates starting at 1L/kg/min or (age [years]+4) L/min, whichever lower, should be considered.