Cukurova Medical Journal (Jun 2022)
Ultrasound measurements of anterior neck soft tissue thickness to predict difficult laryngoscopy in pregnant patients
Abstract
Purpose: The aim of this study is to examine the relationship between the measurement of anterior neck soft tissue thickness and the difficult laryngoscopy in which cesarean section under general anesthesia. Our secondary aim is to determine the efficacy of the other predictive tests and post-induction indicators to detect difficult laryngoscopy in pregnant women. Materials and Methods: One hundred fiftytwo pregnant women (18-45 years old, American Society of Anesthesiologists Physical Status Class II) were included. According to Cormack and Lehane’s scale (Grade I-II: easy laryngoscopy, Grade III-IV: difficult laryngoscopy) patients were divided into two groups. The distance from the skin to the anterior aspect of the trachea was measured at five different levels (hyoid bone, thyrohyoid membrane, vocal cords, thyroid isthmus, and suprasternal notch) with ultrasound. In addition, the other predictive tests and post-induction indicators for predetermining difficult laryngoscopy were recorded. Results: There was no significant difference in the anterior neck soft tissue ultrasound measurements between the groups. Having limited mouth opening (4.80±0.51cm), buck teeth (20%), high Wilson's Risk Score (0.73±0.82), large neck circumference (41.40±2.96cm), inability to bite the upper lip (43%), and high Modified Mallampati Score (33%) were seen statistically significantly more common in the difficult laryngoscopy group. In addition, ‘‘Backward, Upward, Rightward Pressure’’ maneuver, use of gum elastic bougie, high Intubation Difficulty Score, and >2 intubation attempts were more frequently found in the difficult laryngoscopy group. Conclusion: Measuring the anterior neck soft tissue with ultrasound is ineffective for determining difficult laryngoscopy in pregnant women. On the other hand, Mallampati Score, upper lip bite test, mouth opening, neck circumference, buck teeth, and Wilson's Risk Score can be helpful in the determination of difficult laryngoscopy in pregnancies.
