Hyomental Distance Ratio- New Predictor of Difficult Laryngoscopy

Endotracheal intubation in settings such as the intensive care unit (ICU) is often linked with dangers and varies from intubation in the operating room for a variety of reasons. However, examination of the airway prior to intubation is contingent on a number of clinical characteristics with differing prognoses for difficult airways. Recent research aimed to investigate the use of the Hyomental distance ratio (HMDR) in predicting laryngoscopy difficulty for ICU patients.

In this research, 104 critically sick, 18-to-70-year-old ICU patients undergoing tracheal intubation were included. The hyomental distance was determined by pressing a hard plastic ruler on the skin surface immediately above the hyoid bone and measuring the distance to the tip of the anterior-most portion of the mentum (HMD). The HMD was evaluated in both the neutral and extended head positions, and the HMDR was computed. An expert anesthesiologist sedated, pre-oxygenated, induced, and relaxed all patients prior to glottic visualization by direct laryngoscopy. The grade of Cormack-Lehane (CL) was determined without external laryngeal manipulation. The treatment continued according to ICU procedure. Using the Chi-Square test for statistical analysis, it was determined that the p-value of HMDR in evaluating difficult laryngoscopy was less than 0.001, indicating a high level of significance. With a p-value of 0.047, HMD in the extended head position (HDMe) demonstrated modest significance. HMDR 1.2 is a clinically valid individual predictor of laryngoscopy difficulty in ICU patients.

In this research, HMDR had the best sensitivity (88.5 percent) for predicting DVL, followed by HMDn (80.8 percent ). In this investigation, HMDR had the highest specificity, followed by HMDe. In contrast to several investigations where specificity was greater for all HMD parameters, the specificity of these recordings is lower. The total accuracy of HMDR in predicting laryngoscopy difficulties is 86.5 percent, and HMDR is statistically significant with p0.001.

In the critical care setting, we find that HMDR is one of the most reliable and accurate predictors of DVL. HMDR 1.2 may serve as a test threshold. Even though the HMDR is a solid predictor, we would recommend combining it with additional tests, if possible, rather than using it alone.

Reference –

Hrithma D, K R, Mahadevaiah D, et al. (May 28, 2022) A Cross-Sectional Study on Hyomental Distance Ratio (HMDR) as a New Predictor of Difficult Laryngoscopy in ICU Patients. Cureus 14(5): e25435. doi:10.7759/cureus.25435