Can the width of lower tongue base preoperative sonography measurements predict hypoxemia during esophagogastroduodenoscopy under sedation in ASA I-II patients?

The most common complication during esophagogastroduodenoscopy (EGD) under sedation is hypoxemia. There is a scarcity of indicators to predict the risk of hypoxemia during EGD under sedation accurately. The width of the lower tongue base measured by ultrasound (US) is considered to be a significant predictor of the presence and severity of obstructive sleepapnea syndrome (OSAS), which develops hypoxemia by a similar mechanism to EGD under sedation. This study aimed to observe its ability to predict hypoxemia during EGD under sedation.Material and methodsː Adult patients undergoing EGD under sedation at our hospital after assessment in the anesthesia clinic were enrolled in the study. The width of the lower tongue base was measured as the distance between the lingual arteries (DLA) on both sides of the inferior lateral margin of the tongue by US. The primary outcome was hypoxemia defined as the SpO2 <90% for longer than 10 seconds during EGD under sedation. ResultsːA total of 304 patients were successfully included, and hypoxemia was reported in 32 patients (10.5%). The DLA prediction criterion for hypoxemia was >31 mm. The DLA was correlated with hypoxemia (Spearman correlation coefficient, 0.455; p<0.001) and owned the highest area under the receiver operating characteristic curve (0.927; 99% CI, 0.891 to 0.953, compared with that of the other predictors, p< 0.001) with hypoxemia.Conclusionsː The width of the lower tongue base, measured as the DLA by US examination can be used to effectively predict the risk of hypoxemia during EGD under sedation.