Use of ultrasonography in confirming the malposition of the i-gel in pediatric patients: a prospective observational study

BACKGROUND/AIM: This study was designed to observe and compare the performance of fiberoptic laryngeal (FOL) view, leakage test (LT) and ultrasonography (USG) usage in detecting i-gel position in pediatric patients. MATERIALS AND METHODS: One hundred ten consecutive children were included in this single-armed prospective observational study. After anesthetic induction, i-gel placement confirmed using FOL and LT was evaluated using USG in three planes. According to our scoring system, acceptable and unacceptable grades (FOL, LT and USG) were determined to describe placement. Sensitivity and specificity were determined by comparing USG performance with the other two tests. RESULTS: Ultrasonography was found a sensitivity of 20% positive predictive value (PPV) for unacceptable i-gel placement according to FOL grade and a sensitivity of 37.04% with a 100% PPV according to LT grade. USG was found a specificity of 91.84% negative predictive value (NPV) of 91.84% for acceptable i-gel placement according to FOL grade and the NPV specificity of 100% with a 82.65% NPV according to LT grade. CONCLUSION: Ultrasonography demonstrated a very good diagnostic performance in the detection of optimal i-gel placement according to both FOL and LT. However, both FOL and LT showed poor diagnostic performance compared to USG in demonstrating i-gel malposition.