%0 Journal Article %T The cuff-leak test: what are we measuring? %A Daniel De Backer %J Critical Care %D 2004 %I BioMed Central %R 10.1186/cc3031 %X Tracheal extubation of patients is still a major challenge, with the possibility of post-extubation stridor and then re-intubation if the patient is unable to sustain the increase in respiratory work. Stridor is responsible for 15¨C38% of extubation failures [1-3] and for close to 38% of early extubation failures [3]. Recognition of stridor is important because these patients can benefit from close monitoring and from specific therapies including non-invasive respiratory assistance, aerosolized adrenaline (epinephrine), and steroids (even though the efficacy of steroids remains under debate). Ideally, patients at risk of developing laryngeal edema should be identified as early as possible, and the cuff-leak test has been proposed for this purpose. The principle of this test is quite simple and is based on the fact that the air leak around a tracheal tube with a cuff deflated will be inversely related to the degree of laryngeal obstruction generated by laryngeal edema.The cuff-leak test was developed initially in children with croup [4]; extubation was likely to be successful if an air leak could be heard when the baby coughed during positive pressure ventilation. The test was further refined to allow quantitative measurements, using the difference between the expired tidal volume with the cuff inflated and with the cuff deflated: the higher the leak, the lower the likelihood that post-extubation stridor will occur. The discrimination power of the test is highly variable (Table 1), depending on the population investigated, the incidence of post-extubation stridor (ranging from to 4% to 38%), the method of determination of cuff leak (absolute value versus value relative to tidal volume measured with an inflated cuff, number of measurements of tidal volumes averaged, and so on). But perhaps more importantly, the cut-off value should be adapted to the situation; the cut-off that is usually given in most studies assumes an equivalent impact of false positive and false neg %K extubation failure %K laryngeal edema %K stridor %U http://ccforum.com/content/9/1/31