Correlation of Estimation Techniques and Direct Cuff Pressure Measurement technique in assessing endotracheal tube cuff pressures -A Prospective Observational Study

Dr N Keerthana; Dr Sharmila Ranade; Dr Harshal Wagh; Dr B Gowri Shankar

Volume : IX, Issue : XII, December - 2019

Correlation of Estimation Techniques and Direct Cuff Pressure Measurement technique in assessing endotracheal tube cuff pressures -A Prospective Observational Study

Dr N Keerthana, Dr Sharmila Ranade, Dr Harshal Wagh, Dr B Gowri Shankar

Abstract :

The endotracheal tube cuff pressure must be high enough to seal the trachea to prevent micro or frank aspiration but also be low enough to allow perfusion of the tracheal mucosa. Although various cuff inflation techniques are used, there is no standard technique in the literature addressing the method of cuff inflation or cuff pressure maintenance in anaesthetic practice. The purpose of the study is to correlate direct cuff pressure measurement technique (Group A) and estimation techniques like Minimal leak test (Group B), Minimal occlusive volume test (Group C), Palpation of pilot balloon (Group D), Predetermined volume test (Group E) in assessing endotracheal tube cuff pressures. A convenience sample of 144 patients intubated with endotracheal tube size 6.5–8.5 was included. The cuff of endotracheal tube was inflated by anaesthesia provider by using their usual estimation techniques and the cuff pressures were measured with noninvasive aneroid manometer connected to pilot balloon. The results were analysed using appropriate statistical software and a p–value < 0.05 was considered significant. Direct cuff pressure measurement (Group A) showed mean cuff pressures of 29.9±4cmH2O which is in normal range (25–40 cmH2O). Whereas, with other estimation techniques (Group B, C, D, E) the pressures recorded were 37.32±16.40, 37.86±16.13 ,46.21±16.94, 45.19±16.61 cmH2O respectively, which are either too low pressures or too high pressures when compared to normal range pressures. CONCLUSION: The direct cuff pressure measurement technique resulted in normal range cuff pressures when compared to other four estimation techniques. Thus, direct cuff pressure measurement with anaeroid manometer is the safest and simple method to be used to inflate the endotracheal tube cuff and prevent very high or low intracuff pressures. Endotracheal tube cuff pressure monitoring should be practiced routinely in regular anaesthesia practice.