Mask ventilation is a critical part of airway control. While there are ways for assessing the likelihood of difficulties with intubation and rating the view during laryngoscopy, there is no acknowledged scale for grading mask ventilation to our knowledge. 1–4
Langeron et al.5 conducted a study to determine the variables associated with problematic mask ventilation. They discovered that problematic mask ventilation occurred in 5% of all patients and was linked with five factors: age larger than 55 years, body mass index higher than 26 kg/m2, tooth loss, beard, or history of snoring. They classified mask ventilation as challenging in this research when the doctor determined that it was “clinically significant and might have resulted in possible issues if mask ventilation had to be maintained for a longer period of time.” 5 They classified mask ventilation as impossible “when it entirely failed and an other method of breathing was necessary in an emergency.” 5 Other than “tough” and “impossible,” this research did not specify a grading scheme. 5 Adnet6 did advocate the development of a grading scheme in an accompanying editorial. The American Society of Anesthesiologists’ Guidelines for the Management of the Difficult Airway define difficult facemask ventilation as “a situation in which the anesthesiologist is unable to provide adequate face mask ventilation due to one or more of the following problems: insufficient mask seal, excessive gas leak, or excessive resistance to gas ingress or egress.” 7 The recommendations also define the symptoms of insufficient facemask ventilation, but there is no established grading system for facemask ventilation capabilities. 7
We found it beneficial to establish a grading system similar to that used for rating the view during laryngoscopy when developing a perioperative information system. To begin, we selected grades 0–4, as specified in table 1. Additionally, practitioners might include a written explanation of mask ventilation. Table 1 summarizes the prevalence of each grade of ease or difficulty with mask ventilation.
The computerized chart review procedure was approved by the institutional review board. After roughly three weeks, we produced the documentation findings based on the options made (table 1). Following a study of these data, we updated the grading definitions as given in Table 2, excluding the modifiers “easy” and “tough” before grades 1 and 2. After another three weeks, same data were collated again, yielding the findings shown in table 2. The second revision of the grading system resulted in equal percentages for grades 3 and 4, a decrease in grade 1 categories, and a rise in grade 2 classifications. Additionally, we saw a significant drop in the number of comments, which decreased from 1.4 percent to 0.3 percent of instances. We reasoned that the decrease in comments indicated that the second technique of determining mask ventilation grades was simpler for practitioners to pick, although this may have been because persons were more used to the system in general. As with the assessment of the airway and the view of laryngoscopy, assessing the capacity to mask ventilate is subjective and practitioner dependant. It’s worth noting that Langeron et al.5 reported just one incidence of inability to ventilate out of 1,502 patients, while we observed three in 2,621 patients. This high degree of agreement in the occurrence of being unable to ventilate a patient is presumably because it is a more objective (and remembered) incident. We did not discover such agreement in individuals classified as having “difficult mask ventilation” (grade 3). Langeron et al.5 discovered this in 5% of their patients, while we observed a 1.3 percent incidence. This might be because Langeron et al. defined problematic mask ventilation more broadly.
Finally, the most critical grades to describe are the more challenging ones, grades 3 and 4, since they will very certainly alter future anesthetic plans. We have maintained the categories and descriptions described in Table 2 and have found this information to be beneficial in arranging future anesthetics, particularly for patients with problematic intubation.