Estimation of endotracheal tube cuff pressures at Kenyatta National Hospital

Abstract

Objective: To determine the ability of Intensive Care givers to accurately inflate endotracheal tube cuffs using standard syringe technique and estimate endotracheal tube cuff pressure by finger palpation of the pilot balloon. Design: Cross-sectional descriptive/observational study Setting: Kenyatta National Hospital Methods: This descriptive survey of intensive care givers at Ki'\lH used a size 7.5 ETT with a large volume low pressure cuff (portex) in a 2 em diameter rigid tube as a tracheal simulator. Using their choice of a 5 or l Oml syringe, participants inflated the ETTc by standard methods of injecting air and palpating the pilot balloon to estimate ETTc pressure. ETTc pressure was measured using a highly sensitive and accurate manometer (UBV, Suiz Germany). Participants then palpated 9 different EITc previously inf1ated to pressures ranging from extremely low to extremely high, and reported their assessment of inflated as low, normal or high. Results: Participants had 6.1% probability ofinflating ETTc accurately. Majority, 94.7% inflated EITc cuff to high pressures. We sampled 149 participants among them rcu nurses, physician anaesthetists, CO anaesthetists, Registrars in anaesthesia and clinical officer anaesthesia students. Only 6.1 % inf1ated the ETTc to a safe pressure. The average ETTc pressure produced was greater than 91 cmH20. The true mean could not be determined because 3 1 % inflated to pressures greater than the upper limit of manometer sensitivity (120cmH20). Usihg palpation, only 4.1 % of participants were able to accurately detect inappropriately inflated ETTc. Conclusidns: Participants had little ability to inflate ETTc to safe pressure or to estimate pressure of a previously int1ated cuff using standard technique, and most inflated to dangerously high pressures. Clinicians should consider using devices to facilitate safe inf1ation and accurate measurement ofETTc pressure rather than relying solely on standard techniques.