Kinking of catheters during translaryngeal jet ventilation: A bench model investigation of eight devices

Abstract

Objective: To evaluate oxygen flow through several transtracheal devices in native and right angle kinked states. Material and Method: Eight catheter-over-needle, and two oxygen conveyance devices (Enk Flow Modulator 10L/min flow and Manujet III Jet device 15, 30, 50 psi) were examined. Oxygen flow from each catheter was measured five times with three insufflation patterns [continuous insufflation, one second insufflation/ one second pause (1:1), one second insufflation/three second pause (1:3)] in both native, and 90 degree kinked condition. Results: During continuous insufflation, all but the 20G catheter delivered flows of more than 7L/m with all conveyance pressures. With a 1:1 insufflation/pause ratio, catheters smaller than 16G were able to deliver 7L/min flow only with driving pressures of 30 and 50 psi. With a 1:3 insufflation ratio, no catheter could deliver adequate flow with 15 psi(manujet) or with the Enk Flow modulator. Only the Cook catheter and 14G Ravussin were capable at 30 psi. Only the Cook Transtracheal Jet Ventilation Catheter could deliver adequate flow in kinked position, but only at 50 psi. Conclusion: Needle-catheters designed for vascular access are marginally capable of effective TJV. The Cook Transtracheal Jet Ventilation catheter proved to be the most robust device in the kinked state, but only when combined with a high-pressure oxygen conveyance system.