Original Article  Comparison of three difficult endotracheal intubation predictors in obese individuals in an Indian population: Predictors of difficult intubation in Obese Indians

Dr. Sanjay Chatterjee

doi:10.15713/ins.bhj.168

Authors

Dr. Sanjay Chatterjee a:1:{s:5:"en_US";s:64:"Assistant professor, General surgery department, Bombay Hospital";}

DOI:

https://doi.org/10.15713/ins.bhj.168

Keywords:

predictors; laryngoscopy; obesity; airway risk assessment; difficult endotracheal intubation

Abstract

Abstract:

Context:

Unanticipated difficult intubation is a challenge that no single bedside screening test can accurately predict. Independent indices or single anthropometric measurements have demonstrated lower reliability in patients with increased Body mass index (BMI). Using two or three related independent indices is therefore preferred.

Aim:

To assess applicability of three bedside measurements, the modified Mallampati Classification (MMPC), Neck circumference and Thyromental distance ratio (NC/TM) and Neck Circumference minus acromio-acromion distance (NEMA) in obese subset of Indian population.

Design: Prospective observational study

Methods and Material:

One twenty adults with BMI > 29 undergoing general anesthesia were enrolled after consenting. Pre-operative measurements and intubation details were recorded. Difficult intubation was determined using the intubation difficulty scale (IDS≥5 termed difficult). The NC/TM ratio, NEMA, MMPC were compared with respect to sensitivity, specificity, positive, negative predictive value with receiver operating characteristics (ROC) curve and logistic regression.

Statistical analysis used: SPSS software version 25

Results

Incidence of difficult intubation was 12.5%. By binary univariate logistic regression, NC/TM independently predicted difficult intubation in obese {p = 0.00 and exponential B 29.173(95% CI of 5.862 to 145.185)}. NC/TM showed the highest sensitivity, negative predictive value, and largest area under the curve.. Mean NC/TM was 4.71(SD ± 0.44) and mean NEMA was 0.83(SD ± 2.7)

Conclusion

The NC/TM ≥5 with its good sensitivity, specificity, negative and positive predictive values, appears an independently useful, simple bedside test predicting difficult intubation in obese Indian population and superior to MMPC and NEMA.

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