Samprathi M, et al. - Given the common occurrence of postextubation airway obstruction (PEAO) and difficulty in its prediction among children, researchers in this prospective observational study evaluated the hypothesis that intracricoid peritubal free space (IPFS) obtained by deducting the outer diameter of the endotracheal tube in situ (ODTT - provided by the manufacturer) from the ultrasonographically measured internal transverse cricoid diameter (ICDt) is likely to be inversely proportional to the risk of developing PEAO. In this study, laryngotracheal ultrasound was conducted just prior to the first elective extubation in 93 patients (3mo-12yrs) intubated for ≥ 48 h, to measure the IPFS. PEAO developed in 32 (34%) patients, while extubation failure (EF) developed in 17 (18%) patients. Per findings, lesser IPFS is reasonably sensitive and specific to predict PEAO and EF, respectively, with high positive predictive value (PPV). The PPV further improved with combining clinical risk factors and IPFS.