Bedside Evaluation of Efficient Airway Humidification During Mechanical Ventilation of the Critically Ill*

Study objective: To determine the correlation between simple rating of condensation seen in the flex-tube connecting the heating and humidifying device used with the endotracheal tube and hygrometric parameters (absolute and relative humidity and tracheal temperature) measured by psychrometry. Design: Prospective randomized clinical trial. Setting: Medical ICU of Louis Mourier Hospital, Colombes, France, a university-affiliated teaching hospital. Patients: Forty-five consecutive mechanically ventilated critically ill patients. Interventions: Patients undergoing mechanical ventilation were randomly assigned to receive humidification with one of the four heat and moisture exchangers (HMEs) tested or with a conventional heated humidifier. Measurements: The hygrometric performances of four HMEs (BB2215, BB50, and BB100 from Pall Biomedical, Saint-Germaine-en-Laye, France; and Hygrobac-Dar from Mallinckrodt, Miran