You are here

  • Home
  • Archive
  • Volume 7, Issue 5
  • The accuracy of postoperative, non-invasive Air-Test to diagnose atelectasis in healthy patients after surgery: a prospective, diagnostic pilot study

Article Text

Article menu

Download PDFPDF

XML
Anaesthesia
Research
The accuracy of postoperative, non-invasive Air-Test to diagnose atelectasis in healthy patients after surgery: a prospective, diagnostic pilot study
  1. Carlos Ferrando1,
  2. Carolina Romero2,
  3. Gerardo Tusman3,
  4. Fernando Suarez-Sipmann4,5,
  5. Jaume Canet6,
  6. Rosa Dosdá7,
  7. Paola Valls1,
  8. Abigail Villena1,
  9. Ferran Serralta1,
  10. Ana Jurado1,
  11. Juan Carrizo1,
  12. Jose Navarro1,
  13. Cristina Parrilla7,
  14. Jose E Romero8,
  15. Natividad Pozo9,
  16. Marina Soro1,
  17. Jesús Villar5,10,
  18. Francisco Javier Belda1
  1. 1Anesthesiology and Critical Care, Hospital Clínico Universitario Valencia, Valencia, Spain
  2. 2Anesthesiology and Critical Care, Consorci Hospital General Universitari de Valencia, Valencia, Spain
  3. 3Department of Anesthesiology, Hospital Privado de Comunidad, Mar de Plata, Argentina
  4. 4Uppsala Universitet, Uppsala, Sweden
  5. 5CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
  6. 6Anesthesiology and Critical Care, Hospital Universitari Germans Trias i Pujol, Badalona, Spain
  7. 7Department of Radiology, Hospital Clinico Universitario Valencia, Valencia, Spain
  8. 8ITACA Institute (Group IBIME), Universidad Politécnica, Valencia, Spain
  9. 9INCLIVA Clinical Research Institute, Valencia, Spain
  10. 10Research Unit, Hospital Universitario Dr. Negrin, Las Palmas de Gran Canaria, Spain
  1. Correspondence to Dr Carlos Ferrando; cafeoranestesia{at}gmail.com

Abstract

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.

  • postoperative
  • atelectasis
  • oxygenation
  • SpO2
  • adult anaesthesia
  • adult intensive & critical care

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/

https://doi.org/10.1136/bmjopen-2016-015560

Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    View Full Text

    Footnotes

    • Contributors CF and FJB had full access to all data and are responsible for the integrity and the accuracy of the data analysis. Study design: CF, CR, JR, GT, FSS and FJB. Acquisition and analysis of data: CF, CR, JR, RD, GT, MS, PV, AV, FS, AJ, JuC, JN, CP, NP, CR, JR, JV and FJB. Interpretation of data: CF, GT and JaC. Drafting of the manuscript: CF, JV and FJB. Critical revision of the manuscript for intellectual content: CF, GT, FSS, JaC, JV and FJB.

    • Funding This research received no specific grants from any funding agency in the public, commercial or not-for-profit sectors.

    • Competing interests All the authors have completed the ICMJE uniform disclosure form atwww.icmje.org/coi_disclosure.pdf and declare they received/have: no support from any organisation for the submitted work; no financial relationships.

    • Ethics approval The study was approved by the Local Ethics Committee for Clinical Research in accordance with the Declaration of Helsinki (Chairperson: Dr Antonio Peláez), and registered on 28 December 2015 at

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Data sharing statement Additional unpublished data are available by request to the lead author.