Ultrasound versus manipulation to determine an intercostal space for single-port thoracoscopy surgery: A Diagnostic Accuracy Study

Abstract Background:Malposition of the intercostal space used for single-port thoracoscopy surgery can lead to severe problems for patients under general anesthesia. The focus of this study was to assess the accuracy of point-of-care ultrasound in verifying the correct position of the intercostal space used for single-port thoracoscopy surgery. Methods: A total of 200 patientsaged18 to 65 years and classified as ASA status I-Ⅲ who underwent selective single-port thoracoscopic lobectomy were enrolled. After the induction of anesthesia, the patients were placed in a lateral position. An independent thoracic team left the operating room after confirming the incision position. First, the intercostal space was located by a young resident thoracic surgeon (working experience less than 1 year),andthe young thoracic surgeon left the operating room after he or she determined the location. Second, the intercostal space was located by a highly experienced thoracic surgeon (working experience more than 20 years) by manipulation; afterwards, the highly experienced thoracic surgeon left the operating room.Finally, the operation was started by a fixed independent thoracic team. After the chest cavity was opened, the final investigator verified the location of the intercostal space under direct vision through thoracoscopy.The timerequired by ultrasound and manipulation were also recorded. Results: There wereno differences between the manipulation and ultrasound methods in terms of accuracy, which was 87.2%(95% CI0.871-0.873) and 85.6%(95% CI0.854-0.857),respectively (p> 0.05). The inter-relationships between ultrasound and the standard method and between manipulation and the standard method were consistent (p<0.05). Manipulation positioning showed a sensitivity of 90.6% (95% CI0.862-0.950) and specificity of 30%(95% CI0.016-0.584), while ultrasound positioning showed a sensitivity of 87.1%(95% CI0.820-0.921) and specificity of 60%(95% CI0.296-0.904).Compared with that of manipulation positioning, the specificity of ultrasound positioning was higher (p<0.05).No differences inPPV and NPV were found between manipulation and ultrasound positioning (p> 0.05). The timerequired by ultrasound (30.37±17.01s) was significantly shorter than that required by manipulation (41.31±35.42 s)(p<0.05). Conclusions: Compared with the manipulation method, the ultrasound-guided methodcould accurately locate the intercostal space for single-port thoracoscopy surgery.Ultrasound requires less time than manipulation. Trial registration:ISRCTN10722758. Registered 04 June 2019 Keywords：Intercostal space; Positioning; Ultrasound; Manipulation;