Gas flow rates through transtracheal ventilation catheters

The purpose of the study was to measure gas flow rates using different methods of transtracheal ventilation. Wall oxygen flow (WOF) at 10 and 15L/min, and a self-inflating ventilation bag (SIVB) were used to deliver gas flow through three transtracheal catheters: 13, 14, and 16 gauge (5 trials each). WOF mean gas flow rates (L/min) through the 16G, 14G, 13G catheters, respectively were: 15.7, 15.7, 16.8 at 15L/min, 10.5, 10.5, 10.3 at 10 L/min, and 5.7, 7.5, 7.7 via SIVB. SIVB gas flow was not continuous since it required the bag to reinflate, which reduces its calculated flow rate. A 500 cc tidal volume can be delivered within 3 seconds (WOF) and 5 seconds (SIVB). Catheter size did not substantially affect gas flow rates (Poiseuille’s law not applicable). Transtracheal ventilation is best done by using WOF, but if a device to perform this is not available, then an SIVB may still be sufficient.