Optimal endotracheal cuff pressure in the intensive care setting: A pilot study

Abstract

Abstract Background: Endotracheal tube cuff pressure is clinically measured by “minimal occlusion (MOC) and minimal leak (MLK) techniques” by palpating and auscultating the neck for end-inspiratory “elimination” or “allowance” of subtle air leak, respectively. This study was done to determine the validity and reliability of MOC and MLK techniques, manometric endotracheal tube cuff-pressure measurement of 20–30 cm H2O being reference standard. Materials and Methods: A prospective, observational study was conducted in adult patients requiring positive pressure ventilation in the medical intensive care unit (ICU). Two investigators independently assessed MOC and MLK twice on days 2 and 3 of intubation. ICU registrar, unaware of earlier readings, noted manometric cuff-pressure within 5 min. Inter-observer reliability was calculated using intraclass correlation coeffiient (ICC). Validity of measurement was assessed using accepted reference standard of 20–30 cm H2O by manometer. Results: Sixty patients between 17 and 82 years, on positive pressure ventilation were evaluated twice, by two investigators resulting in 240 observations. Mean manometric pressures were 15.7 + 2.6 and 12.2 + 2.4 cm H2O using MOC and MLK techniques to maintain adequate ventilation. ICC measured for reliability was high at 0.69 and 0.67 for MOC and MLK techniques. Adequate ventilation was maintained in all patients and 57 of 60 (95%) were discharged alive without significant ventilatory complications. Conclusions: Cuff pressures needed to maintain effective positive pressure ventilation was well below the accepted levels of 20–30 cm of H2O in majority patients. MOC and MLK techniques have high reliability. The result of the study has the implications on ICU ventilatory care.