A Prospective Observational Study to Assess the Diagnostic Accuracy of Suprasternal Versus Subxiphoid Ultrasonography for Endotracheal Intubation in Patients Undergoing Elective Surgery.

OBJECTIVE

This study compared the diagnostic accuracy and time efficiency of suprasternal versus subxiphoid ultrasonography for endotracheal tube (ETT) confirmation.

METHODOLOGY: A prospective observational study was conducted on 50 patients classified as American Society of Anesthesiologists Physical Status (ASA-PS) 1 or 2 who were scheduled for elective surgical procedures under general anesthesia. After endotracheal intubation (ETI), tube placement was verified using three methods: suprasternal ultrasonography, visualizing the characteristic "bullet sign"; subxiphoid ultrasonography, assessing diaphragmatic motion; and continuous waveform capnography. The time required for confirmation and the diagnostic accuracy of each method were systematically recorded.

RESULTS

Suprasternal ultrasound was significantly faster (5.58 ± 1.14 seconds) than capnography (31.50 ± 4.84 seconds) (p < 0.001) and auscultation (33.38 ± 4.58 seconds) (p < 0.001). Subxiphoid ultrasound took 20.32 ± 4.60 seconds (p < 0.001). No false positives or false negatives were observed. Both ultrasound methods showed 100% agreement with capnography.

CONCLUSION

Suprasternal and subxiphoid ultrasonography are equally accurate but faster than capnography for ETT confirmation in low-risk surgical patients. Due to its speed, suprasternal ultrasound may be preferable in time-critical scenarios.