Prediction of Difficult Airway in Cesarean Section Using Preoperative Airway Assessment Tests

Overview

This observational study (OB-DIFF-AIRWAY: Obstetric Difficult Airway Study) aimed to evaluate the accuracy of commonly used preoperative airway assessment tests in predicting difficult airway management in obstetric patients undergoing cesarean section. Difficult airway remained a significant cause of anesthesia-related complications, particularly in pregnant patients due to physiological and anatomical changes. Adult pregnant women scheduled for elective or urgent cesarean section underwent standard preoperative airway assessment, including Mallampati classification, thyromental distance, interincisor distance, neck circumference, and other routine clinical evaluations. Airway management during anesthesia was performed according to standard clinical practice. No additional intervention was applied for the purpose of the study. The relationship between preoperative airway assessment findings and actual airway management difficulty was analyzed. The results of this study may help improve preoperative airway evaluation strategies and enhance patient safety in obstetric anesthesia.

Difficult airway management is one of the most critical challenges in anesthetic practice and is associated with increased morbidity and mortality. Obstetric patients represent a particularly high-risk population due to pregnancy-related physiological changes such as airway edema, weight gain, reduced functional residual capacity, and increased oxygen consumption. Despite routine use of various preoperative airway assessment tests, their predictive value in obstetric patients remains controversial. This prospective observational study was conducted to evaluate the reliability of commonly used preoperative airway assessment tests in predicting difficult airway management in patients undergoing cesarean section. The study was performed at Akdeniz University Hospital between August 23, 2023, and August 23, 2024. Adult obstetric patients scheduled for elective or urgent cesarean section under anesthesia were included. Patients with known airway pathology, prior difficult airway history requiring advanced airway techniques, or incomplete airway assessment data were excluded according to predefined criteria. Preoperative airway assessment was performed as part of routine anesthetic evaluation and included Mallampati classification, thyromental distance, interincisor distance, neck circumference, and other standard clinical parameters. No additional procedures or interventions were introduced for research purposes. Anesthetic management and airway techniques were determined by the attending anesthesiologist in accordance with institutional standards. Airway management difficulty was recorded intraoperatively based on predefined clinical criteria, including difficulty with mask ventilation, laryngoscopy, or tracheal intubation. The association between preoperative airway assessment findings and observed airway difficulty was analyzed using appropriate statistical methods. Difficult airway management was defined as the presence of at least one of the following predefined intraoperative criteria: difficult mask ventilation (Han classification ≥ 3), difficult laryngoscopy (Cormack-Lehane grade III-IV), or failure of tracheal intubation on the first attempt. Patients were enrolled using a consecutive non-probability sampling approach, including all eligible obstetric patients undergoing cesarean delivery during the study period. The sample size was determined by the consecutive inclusion of all eligible patients undergoing cesarean delivery at the study center during the predefined study period. The primary objective of the study was to assess the predictive value of individual and combined airway assessment tests for difficult airway management in obstetric patients. Secondary objectives included identifying potential risk factors associated with airway difficulty and evaluating the overall incidence of difficult airway in the study population. The findings of this study are expected to contribute to improved preoperative airway evaluation and risk stratification in obstetric anesthesia, thereby enhancing patient safety and clinical outcomes.