Preoperative assessment for difficult intubation in general and ENT surgery: predictive value of a clinical multivariate risk index

Abstract

Several clinical multifactorial indexes have been described for predicting difficult laryngoscopy or intubation, or both, mostly in general surgery, and less frequently in ENT surgery. The objective of this study was to develop and validate a single clinical index for prediction of difficulty in tracheal intubation in both ENT and general surgery. We studied a population of 1200 consecutive ENT and general surgical patients. Clinical criteria were tested using univariate and multivariate analysis. Difficult intubation was defined as requiring unusual techniques. Logistic regression identified seven criteria as independent predictors of difficult tracheal intubation; previous history of difficult intubation; pathologies associated with difficult intubation; clinical symptoms of pathological airway; inter-incisor gap and mandible luxation; thyromental distance; head and neck movement; and Mallampati's modified test. Point values were assigned to each of these factors in proportion to regression coefficients representing the relative weight of each predictive intubation difficulty factor, the sum comprising the score. The best predictive threshold was chosen using a receiver operating characteristic curve. We then prospectively studied and validated the score in a population of 1090 consecutive ENT and general surgery patients. The sensitivity and specificity of the predictions were 94% and 96% in general surgery, 90% and 93% in non-cancer ENT surgery, and 92% and 66% in ENT cancer surgery, respectively.

A documented previous difficult tracheal intubation as a prognostic test for a subsequent difficult tracheal intubation in adults

“…Our estimates differ from previous reported results. A positive predictive value between 69% [9] and 78% [8] and an OR of 9.5 reported by El‐Ganzouri et al. [9] are significantly greater than our findings.…”

A documented previous difficult tracheal intubation as a prognostic test for a subsequent difficult tracheal intubation in adults

“…Our estimates differ from previous reported results. A positive predictive value between 69% [9] and 78% [8] and an OR of 9.5 reported by El‐Ganzouri et al. [9] are significantly greater than our findings.…”

Predicting Difficult Intubation in Surgical Patients Scheduled for General Anaesthesia: A Prospective Study of 435 Patients

“…Furthermore, large breasts, short neck, restricted mouth opening and limitation of flexion and extension of cervical spine and atlanto-occipital joint all contribute to this situation 32 . Nevertheless, many authors 9,12,23,24 found no correlation between difficult intubation and age, sex and weight, which is in concordance to present study. Turkan et al 33 had an idea that the predictive parameters should be reconsidered in the context of age and sex.…”

Prediction of difficult laryngoscopy: Extended mallampati score versus the MMT, ULBT and RHTMD

“…[1234202122] The incidence of DVL was 6.9% in our study and it was comparable with the some previous studies. [202122] The difference in incidence of DVL can be due to various factors such as different anthropometric features that exists among populations, unavailability of uniform grading in description of laryngeal views, application of cricoids pressure, position of head, the degree of muscle relaxation and the type or size of laryngoscope blade. Our data showed that the AUC of ROC for RHTMD and ULBT was 0.845 and 0.820 respectively, whereas the AUC for the corresponding EMSand MMT was 0.703 and 0.569 respectively.…”

A documented previous difficult tracheal intubation as a prognostic test for a subsequent difficult tracheal intubation in adults

“…Our estimates differ from previous reported results. A positive predictive value between 69% [9] and 78% [8] and an OR of 9.5 reported by El‐Ganzouri et al. [9] are significantly greater than our findings.…”

Predicting Difficult Intubation in Surgical Patients Scheduled for General Anaesthesia: A Prospective Study of 435 Patients

“…Furthermore, large breasts, short neck, restricted mouth opening and limitation of flexion and extension of cervical spine and atlanto-occipital joint all contribute to this situation 32 . Nevertheless, many authors 9,12,23,24 found no correlation between difficult intubation and age, sex and weight, which is in concordance to present study. Turkan et al 33 had an idea that the predictive parameters should be reconsidered in the context of age and sex.…”

Prediction of difficult laryngoscopy: Extended mallampati score versus the MMT, ULBT and RHTMD

“…[1234202122] The incidence of DVL was 6.9% in our study and it was comparable with the some previous studies. [202122] The difference in incidence of DVL can be due to various factors such as different anthropometric features that exists among populations, unavailability of uniform grading in description of laryngeal views, application of cricoids pressure, position of head, the degree of muscle relaxation and the type or size of laryngoscope blade. Our data showed that the AUC of ROC for RHTMD and ULBT was 0.845 and 0.820 respectively, whereas the AUC for the corresponding EMSand MMT was 0.703 and 0.569 respectively.…”

A documented previous difficult tracheal intubation as a prognostic test for a subsequent difficult tracheal intubation in adults

“…Our estimates differ from previous reported results. A positive predictive value between 69% [9] and 78% [8] and an OR of 9.5 reported by El‐Ganzouri et al. [9] are significantly greater than our findings.…”

Predicting Difficult Intubation in Surgical Patients Scheduled for General Anaesthesia: A Prospective Study of 435 Patients

“…Furthermore, large breasts, short neck, restricted mouth opening and limitation of flexion and extension of cervical spine and atlanto-occipital joint all contribute to this situation 32 . Nevertheless, many authors 9,12,23,24 found no correlation between difficult intubation and age, sex and weight, which is in concordance to present study. Turkan et al 33 had an idea that the predictive parameters should be reconsidered in the context of age and sex.…”

Prediction of difficult laryngoscopy: Extended mallampati score versus the MMT, ULBT and RHTMD

“…[1234202122] The incidence of DVL was 6.9% in our study and it was comparable with the some previous studies. [202122] The difference in incidence of DVL can be due to various factors such as different anthropometric features that exists among populations, unavailability of uniform grading in description of laryngeal views, application of cricoids pressure, position of head, the degree of muscle relaxation and the type or size of laryngoscope blade. Our data showed that the AUC of ROC for RHTMD and ULBT was 0.845 and 0.820 respectively, whereas the AUC for the corresponding EMSand MMT was 0.703 and 0.569 respectively.…”