Craniocervical extension improves the specificity and predictive value of the Mallampati airway evaluation

BACKGROUND: The modified Mallampati (MMP) classification is a standard airway examination that assesses mouth opening and structures within the oral cavity. Recent data suggest that maximal mouth opening (as measured by interdental distance) is possible only with extension of the craniocervical junction. Because the MMP examination is performed with the head in a neutral position, the airway may appear worse because of submaximal interdental distance. We hypothesized that adding craniocervical extension to the MMP would allow for greater mouth opening, lower scores, and less false positives than the traditional MMP examination. METHODS: Multiple clinicians with at least 1 yr of airway experience evaluated adult airways (n = 60) with the MMP examination (with head in neutral position). The same examination was then repeated with the addition of craniocervical extension (Extended Mallampati Score, EMS). RESULTS: On average, craniocervical extension decreased the MMP class (P < 0.002). The EMS improved specificity from 70% to 80% and positive predictive value from 24% to 31% when compared with the traditional MMP. The sensitivity (83%) was the same for MMP and EMS. CONCLUSIONS: Craniocervical extension improves the specificity and positive predictive value of the MMP airway evaluation while retaining sensitivity of the traditional MMP examination. The introduction of the EMS into clinical practice should be considered.