Evaluation of pressure in water-filled endotracheal tube cuffs in intubated patients undergoing hyperbaric oxygen treatment.

Abstract

Inflating endotracheal tube cuffs using water instead of air before hyperbaric oxygen treatment (HBOT) is common. The objective of this study was to assess cuff pressure (Pcuff), when the cuff was inflated using water, in normobaric conditions and during HBOT. This was a prospective, observational study taking place in hyperbaric centre and intensive care unit of the University Hospital of Lille. Every patient who required tracheal intubation and HBOT at 253.3 kPa (2.5 atmospheres absolute [atm abs]) was included. Pcuff was measured using a pressure transductor connected to the cuff inflating port. Measurements were performed at 'normobaria' (1 atm abs) and during HBOT at 2.5 atm abs. Thirty patients were included between February and April 2016. Recordings were analysable in 27 patients. Mean Pcuff at normobaria was 60.8 (SD 42) cmH2O. Nineteen (70%) of patients had an excessive Pcuff (higher than 30 cmH2O). Coefficient of variation was 69%. Mean Pcuff at 2.5 atm abs was 51.6 (40.7) cmH2O, significantly lower than at normobaria (P < 0.0001). Coefficient of variation was 79%. In only five (18%) patients was Pcuff < 20 cmH2O at 2.5 atm abs. In normobaric conditions, when the cuff was inflated using water and not specifically controlled Pcuff was not predictable. The cuff was typically over-inflated exceeding safe pressure. During HBOT Pcuff decreased slightly.