Diagnostic Accuracy of Auscultation During General Anesthesia by Taking Fiberoptic Bronchoscopy as Gold Standard

Abstract

Objective: To evaluate the diagnostic accuracy of auscultation in the detection of inappropriate positioning of endotracheal tube, in patients undergoing elective surgeries, by taking fiberoptic bronchoscopy as gold standard.

Study design: cross sectional study

Place and duration: Department of anesthesia, Nishtar Hospital, Multan

Methodology: A total of 205 patients admitted in general surgery ward were included in the study. The pre-operative assessment was done one day before surgery. The level of difficulty of intubation was assessed during pre-operative assessment.  SPSS version 23 was used for data analysis. Tests of significance chi square and t-test were applied. P-value < 0.05 was taken as statistically significant.

Results: Therefore, the estimated sensitivity was 72.03%. The estimated specificity was 65.6%. Positive predictive value was 73.9% and negative predictive value was 63.3%. Two hundred and five patients were included in this study of both genders. Gender distribution revealed as n=144 (70.2%) males and n=61 (29.8%) females. The mean age of the patients was 38.92±10.61years. ASA status I and II observed as n=121 (59.0%) and n=84 (41.0%), respectively. Mallampati grading I and II observed as n=127 (62.0%) and n=78 (38.0%), respectively. Laryngoscopy grading I and II observed as n=135 (65.9%) and n=70 (34.1%), respectively.

Practical Implication: The main objective of this study was to evaluate the relative diagnostic accuracy of auscultation during GA. Therefore, we evaluated each technique's sensitivity, specificity, (PPV), (NPV) and overall accuracy in detecting incorrect endotracheal tube positioning.

Conclusion: The five point auscultation technique is a reliable method of confirmation of endotracheal intubation, as verified by flexible fiberoptic bronchoscope.

Keywords: Auscultation, Fiberoptic bronchoscopy, General analgesia, Diagnostic accuracy, sensitivity.