Prevalence of Major Vessels Underlying the Potential Incision Site for Emergency Front of Neck Airway Access in Adult Surgical Patients With Impalpable Neck Anatomy

Patients undergoing general anesthesia require assistance with their breathing and with the delivery of oxygen to their lungs. To achieve this, an anesthesiologist inserts a type of plastic breathing tube into the airway via the mouth called an endotracheal tube or laryngeal mask airway. In rare circumstances, the anesthesiologist may not be able to adequately provide oxygen via these methods. In this life-threatening situation, an anesthesiologist may be forced to make an incision in the front of the neck to access the trachea (windpipe) so that emergency oxygen can be provided. This life-saving technique is known as emergency front-of-neck access (eFONA) and is used to prevent low oxygen levels which cause irreversible brain damage and/or death.

This rarely performed procedure carries a risk of harm from bleeding, injury to the airway or inability to access the trachea to provide oxygen. Emergency front of neck access is more likely to be required in patients with abnormal airway anatomy, for example, in patients with obesity and large neck circumference, neck cancer, or a history of head and neck radiation therapy. Though the optimal technique for eFONA is not clear, prominent guidelines advise the use of an 8-10cm incision upwards from the top of the breastbone in order to identify airway structures which cannot be easily felt by the anesthesiologist from the front of the intact neck. This differs from patients who have airway structures which may be easily located at the front of the neck, whereby a smaller incision may be made or a needle inserted into the trachea (widepipe) to provide oxygen. The neck contains major blood vessels which lie close to the airway and these blood vessels may be injured during the 8-10cm incision, creating further difficulty accessing the airway to provide life-saving oxygen.

This study aims to assess for the presence and size of major blood vessels which may be damaged by this incision by using non-invasive ultrasound which will be placed on the skin of your neck to assess for such blood vessels prior to you undergoing anesthesia.

Our study aims to assess the normal anatomy in the adult population such as yourself to understand what to expect when managing patients who require this life-saving therapy.