AN OBSERVATIONAL PROSPECTIVE STUDY COMPARING RATIO OF PATIENTS' HEIGHT TO THYROMENTAL DISTANCE WITH OTHER AIRWAY ASSESSMENT TESTS FOR PREDICTING DIFFICULT ENDOTRACHEAL INTUBATION.
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Keywords
Difficult Airway, Airway Assessment , Predictive Test
Abstract
OBJECTIVE : Preoperatively done airway assessment reduces the airway complications and hence decreases the patients morbidity and mortality under general anesthesia. So it is very important to find out a single good and efficient preoperative airway assessment test. Our primary objective was to determine the efficiency of the ratio of height to thyromental distance test(RHTMD) as compared to multiple other airway assessment test for prediction of difficult airway.
DESIGN : A prospective, observational, and single-center study.
SETTING: Preoperative room and Operation theatre
PARTICIPANT: The study included 250 consecutive patients, both male and female, aged between 18 and 75 years, who were scheduled to undergo elective surgery requiring general anesthesia and endotracheal intubation.
INTERVENTION:An airway assessment was conducted in the preoperative room, and the anesthesiologist performing the intubation was unaware of the results of the preoperative airway assessment. The Cormack-Lehane grade(CL Grade) was later recorded during the intubation procedure. The airway difficulty level of the CL Grade was then compared with the preoperatively done airway assessment.
RESULTS: RHTMD exhibited the highest sensitivity(98%) ,specificity (93.22), positive and negative predictive value(95.52%,92%)) ,accuracy(96.98%) and the highest AUC value of 0.905, signifying excellent discriminative ability as compared to other studied airway predictors. The incidence of difficult airway predicted by RHTMD was 13% which was close to the actual incidence of difficult airway as shown by CL grading.(14%) Moreover all the difficult airway predicted by RHTMD were true positives.
CONCLUSION: RHTMD appears to be a promising test even if done alone for predicting difficult airway.
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Anupriya saxena
Associate Professor , Department of Anesthesia, Government Institute of Medical Science, India.
Address: Flat-9, Type:5 Block F Gautam Budha University Greater Noida: Uttar Pradesh
Mobile No:9953090044
Nazia Nazir
Professor , Department of Anesthesia, Government Institute of Medical Science, India
Savita Gupta
Associate Professor , Department of Anesthesia, Government Institute of Medical Science, India
Abhishek Bharti
Assistant Professor , Department of Community Medicine , Government Institute of Medical Science, India.
Ruchi Singh
Assistant Professor , Department of Anesthesia, Government Institute of Medical Science, India