Endotracheal cuff pressures in paediatric patients undergoing general anaesthesia at a central academic hospital

Abstract

Background Paediatric endotracheal intubation plays an integral role not only in anaesthesia but in many other disciplines where having a secure airway is a priority. Studies challenging historical findings regarding paediatric airway anatomy are leading to increased use of cuffed endotracheal tubes (ETTs) in the paediatric population. Manufacturers of cuffed paediatric ETTs recommend a safe sealing pressure of 11 – 20 centimetres of water (cm H2O) and no higher. The aim of this study was to determine ETT cuff pressures in paediatric patients using an aneroid manometer. The study then compared various ETT cuff inflation techniques and the level of training of anaesthetists to the measured ETT cuff pressure. Methods A cross-sectional, contextual research design was used in this study. The population group studied were paediatric patients that presented to the operating and diagnostic theatre complexes of Chris Hani Baragwanath Academic Hospital (CHBAH) for procedures under general anaesthesia (GA) administered with a cuffed ETT. A convenience sampling method was used. In consultation with a biostatistician a sample size of 87 was calculated. Informed written consent and assent was obtained from the caregivers and study participants in a deferred manner. Data was collected on weekdays and weekends. Paediatric patients undergoing GA were screened for enrolment in the study. Written informed consent from the patient’s anaesthetist was obtained before ETT cuff pressure measurement took place. Data was collected by the researcher using a standardised data collection sheet. The anaesthetist responsible for inflating the ETT cuff was asked what technique was used for ETT cuff inflation and this was documented together with the ETT cuff pressure obtained. Results The final study sample included 91 participants. In the study, 56 (61.54%) patients were subjected to inadequate sealing pressures, where the ETT cuff pressure was below 11 cm H2O and only 25 (27.47%) patients had an ETT cuff pressure ranging between 11-20 cm H2O. The 4 results also showed significant variability (p=0.011) on the ETT cuff pressure depending on the inflation method used. There was no difference in ETT cuff pressure measurement based on the experience of the person placing the ETT and inflating the cuff. Conclusions Optimal sealing pressures of ETT cuffs using subjective inflation techniques were not achieved in most paediatric patients undergoing GA at CHBAH. ETT cuff pressures should be monitored routinely using an objective method such as an aneroid manometer.