TY - JOUR T1 - The accuracy of postoperative, non-invasive Air-Test to diagnose atelectasis in healthy patients after surgery: a prospective, diagnostic pilot study JF - BMJ Open JO - BMJ Open DO - 10.1136/bmjopen-2016-015560 VL - 7 IS - 5 SP - e015560 AU - Carlos Ferrando AU - Carolina Romero AU - Gerardo Tusman AU - Fernando Suarez-Sipmann AU - Jaume Canet AU - Rosa Dosdá AU - Paola Valls AU - Abigail Villena AU - Ferran Serralta AU - Ana Jurado AU - Juan Carrizo AU - Jose Navarro AU - Cristina Parrilla AU - Jose E Romero AU - Natividad Pozo AU - Marina Soro AU - Jesús Villar AU - Francisco Javier Belda Y1 - 2017/07/01 UR - http://bmjopen.bmj.com/content/7/5/e015560.abstract N2 - Objective To assess the diagnostic accuracy of peripheral capillary oxygen saturation (SpO2) while breathing room air for 5 min (the ‘Air-Test’) in detecting postoperative atelectasis.Design Prospective cohort study. Diagnostic accuracy was assessed by measuring the agreement between the index test and the reference standard CT scan images.Setting Postanaesthetic care unit in a tertiary hospital in Spain.Participants Three hundred and fifty patients from 12 January to 7 February 2015; 170 patients scheduled for surgery under general anaesthesia who were admitted into the postsurgical unit were included.Intervention The Air-Test was performed in conscious extubated patients after a 30 min stabilisation period during which they received supplemental oxygen therapy via a venturi mask. The Air-Test was defined as positive when SpO2 was ≤96% and negative when SpO2 was ≥97%. Arterial blood gases were measured in all patients at the end of the Air-Test. In the subsequent 25 min, the presence of atelectasis was evaluated by performing a CT scan in 59 randomly selected patients.Main outcome measures The primary study outcome was assessment of the accuracy of the Air-Test for detecting postoperative atelectasis compared with the reference standard. The secondary outcome was the incidence of positive Air-Test results.Results The Air-Test diagnosed postoperative atelectasis with an area under the receiver operating characteristic curve of 0.90 (95% CI 0.82 to 0.98) with a sensitivity of 82.6% and a specificity of 87.8%. The presence of atelectasis was confirmed by CT scans in all patients (30/30) with positive and in 5 patients (17%) with negative Air-Test results. Based on the Air-Test, postoperative atelectasis was present in 36% of the patients (62 out of 170).Conclusion The Air-Test may represent an accurate, simple, inexpensive and non-invasive method for diagnosing postoperative atelectasis.Trial Registration NCT02650037. ER -