Peak Expiratory Flow During Mechanical Insufflation-Exsufflation: Endotracheal Tube Versus Face Mask

Abstract

Background: Mechanical insu ation-exsu ation (MI-E) applied through the endotracheal tube (ET) can effectively eliminate airway secretions in intubated patients. However, the effect of the interface (ET vs. facemask) on expiratory air ow generated by MI-E has not been investigated. This study aimed to investigate the effect of the ET on peak expiratory ow (PEF), along with other associated factors that could in uence PEF generated by MI-E. Methods: Intubated participants received two sessions of MI-E via ET therapy per day for two consecutive days. One MI-E session consisted of ve sets of either constant (+40/-40 cmH 2 O) or incremental (+30/-30 to +50/-50 cmH 2 O) pressure applications. Following extubation, MI-E sessions were repeated using facemask. Expiratory air ow during MI-E therapy was measured, and repetitive PEF measurements during each session were analysed using linear mixed-effect and generalised linear mixed models. Results: A total of 12 participants (9 [75.0%] men; mean [SD] age, 74.0 [10.2] years) completed all MI-E sessions with both ET and facemask interfaces. The PEF generated during MI-E treatment was in uenced by the pressure gradient, number of session repetitions, and interface (ET vs. facemask). Adjusted mean PEF values for MI-E via ET and facemask at +40/-40 cmH 2 O were -2.521 and -3.114 L/s, respectively, and -2.956 and -3.364 L/s at +50/-50 cmH 2 O, respectively. At a pressure gradient of +40/-40 cmH 2 O, only 172 of 528 MI-E trials via ET (32.6%) achieved a PEF faster than -2.7 L/s, whereas 304 of 343 MI-E trials via facemask (88.6%) exceeded the PEF cut-off value.Conclusions: MI-E via ET generated slower PEF than via facemask, suggesting that a higher-pressure protocol should be prescribed for intubated patients. An insu ation-exsu ation pressure of at least +50/-50 cmH 2 O should be considered to produce a PEF faster than 2.7 L/s, and the applications were safe and feasible for patients under invasive mechanically ventilation.

Effect of body position on peak expiratory flow during mechanical insufflation–exsufflation in people with cervical spinal cord injury: a pilot study

“…This flowmeter was formally calibrated and validated annually by IMT Analytics to ensure that the maximal uncertainty error was within 0.75% for all measurements. Expiratory airflow was measured as a negative value; therefore, the lowest value during exsufflation was the PCF, which could be calculated from each cough with continuous airflow measurement 28 . The total insufflation volume (TIV) was calculated through integration by squaring insufflation time and flow, as follows: volume (L) = time (s) × flow (L/s).…”

Mechanical Insufflation-Exsufflation: Considerations for Improving Clinical Practice

“…These settings generated an expiratory flow of 4.09 L/sec or 245 L/min [ 52 ]. Hyun and co-workers [ 32 ] evaluated CPFs generated with and without an artificial airway, again higher pressures were required to generate the greatest expiratory flows. However, higher flows were seen for the same pressure when MI-E was delivered via the upper airway rather than the artificial airway.…”

“…Increased cough peak flow [18][19][20][21][31][32][33] Increased secretion clearance [26,34] Improvements in lung compliance [26,34] Short term improvements in forced vital capacity [35] Clinical benefits…”