Comparison of five conventional methods and capnography in the detection of tube placement in endotracheal intubation
Nimet Bilal Erdem1, İsmet Parlak2, Çağrı Kokkoz3, Emirhan Erdem4, Necmiye Yalçın Ocak4
1Department of Emergency Medicine, İzmir Katip Çelebi Atatürk Training and Research Hospital, İzmir, Turkey
2Department of Emergency Medicine, İzmir Bozyaka Training and Research Hospital, İzmir, Turkey
3Department of Emergency Medicine, Çiğli Regional Education Hospital, İzmir, Turkey
4Department of Emergency Medicine, İzmir Tepecik Training and Research Hospital, İzmir, Turkey
Keywords: Capnography; confirmation; intubation
Abstract
Objectives: The aim of this study was to compare the sensitivity and specificity of the conventional methods with the gold standard method, capnography for detection of endotracheal tube (ETT) intubation, and the reliability of these conventional methods when the capnometer device is unavailable.
Patients and methods: In this prospective cross-sectional study, patients were chosen according to inclusion criteria. The tube’s passing through the vocal cords, blurring of ETT, hearing bilateral and equal sounds on lung auscultation, not hearing sounds on stomach auscultation, and observing chest expansion were the conventional methods used for confirmation of the ETT position.
Results: A total of 84 patients who met inclusion criteria were included in the study. Outcomes of 96 intubations were evaluated. For confirmation of ETT position, sensitivity of the tube’s passing through the vocal cords was 93%, specificity was 100%, positive predictive value (PPV) was 100%, and negative predictive value (NPV) was 67%. Sensitivity of lung auscultation was 100%, specificity was 83%, PPV was 98%, and NPV was 100%. Sensitivity of stomach auscultation was 90%, specificity was 100%, PPV was 100%, and NPV was 45%. When lung and stomach auscultation were evaluated together, sensitivity, specificity, PPV, and NPV were 100%.
Conclusion: We believe that the tube’s passing through the vocal cords, hearing bilateral and equal sounds on lung auscultation, and hearing no sounds on stomach auscultation could be used for confirming ETT position in the absence of capnography however the combined use of these methods is more reliable and effective.