Which of the following correlates to an increased likelihood of difficult laryngoscopy?
Neck flexibility of greater than 35 degrees
Thyromental distance greater than 6cm
Interincisor gap less than 3cm
Absence of teeth
The interincisor gap refers to the patient’s mouth opening. Patients with small mouth openings are often more difficult to intubate because of the inability to place the laryngoscope easily. Greater neck flexibility, a thyromental distance of greater than 6cm, and the absence of teeth are all associated with easier direct laryngoscopy.