Risk factors associated with difficult mask ventilation
(1) age >= 57 years
(2) body mass index (BMI) >= 30 kilograms per square meter
(3) presence of a beard
(4) history of snoring
(5) Mallampati Grade III or IV (using modified scale of Samsoon and Young)
(6) severely limited jaw protrusion
Risk factors for difficult or impossible mask ventilation and difficult intubation:
(1) limited or severely limited jaw protrusion
(2) thick neck or obese
(3) sleep apnea
(4) snoring
(5) body mass index (BMI) >= 30 kilograms per square meter
where:
• The p value for BMI is 0.053 for difficult or impossible mask ventilation.
• Many patients with a history of snoring will have sleep apnea.
• A history of difficult mask ventilation or intubation should also be looked for.
• In the implementation will use the failure to see the fauces (the opening and its walls from the mouth to the pharynx) as the criteria for Mallampati class III or IV (see 31.05.01)
Interpretation:
• minimum number of risk factors for difficult mask ventilation: 0
• maximum number of risk factors for difficult mask ventilation: 6
• The presence of 2 or more risk factors is associated with a significant risk for difficult mask ventilation.
