Ultrasound or landmark for identification of the cricothyroid membrane.

INTERVENTION: This study aims to compare the speed and accuracy of ultrasound versus landmark technique of identifying the cricothyroid membrane (CTM) and to secondarily assess the confidence of providers in the method that they have undertaken. Patients will have their CTM identified via use of ultrasound immediately prior to undergoing routine CT imaging of the cervical spine. This will be performed by study staff (consultant emergency physicians or advanced trainees in emergency medicine, who have completed the training protocol and basic credentialing in emergency ultrasound, with at least eFAST and AAA competency). The CTM will marked by placement of a radiopaque marker and held in place using micropore tape. This will be removed at completion of the CT scan. CONDITION: Airway management Cannot intubate, cannot oxygenate Cricothyroidotomy PRIMARY OUTCOME: The primary outcome will be met if the centre of a radio‐opaque marker is within the boundaries of the CTM as identified by computed tomography. SECONDARY OUTCOME: Clinician confidence in the accuracy of marker placement for ultrasound or landmark technique (on a 10‐ point numerical rating scale). Clinician preference for ultrasound or landmark technique (on a 10‐ point numerical rating scale). Time from commencement to final placement of marker for ultrasound or landmark technique. To determine if there is a significant difference in accuracy between ultrasound and landmark CTM identification in patients with a BMI greater than or equal to 25. ; ; The accuracy of the technique will be assessed by calculating the percentage of patients in each group where the centre of the radio‐opaque marker lies over any part of the cricothyroid membrane in the judgement of the assessing radiologists (who will be blinded to the technique used to place the marker). INCLUSION CRITERIA: Emergency department patients aged greater than or equal to 18 years, requiring computed tomography of the cervical spine for any indication.