 Tracheal intubation is not a simple procedure and the consequences of failure are grave . Therefore , the patient is carefully evaluated for potential difficulty or complications beforehand . This involves taking the medical history of the patient and performing a physical examination , the results of which can be scored against one of several classification systems . The proposed surgical procedure ( e.g. , surgery involving the head and neck , or bariatric surgery ) may lead one to anticipate difficulties with intubation . Many individuals have unusual airway anatomy , such as those who have limited movement of their neck or jaw , or those who have tumors , deep swelling due to injury or to allergy , developmental abnormalities of the jaw , or excess fatty tissue of the face and neck . Using conventional laryngoscopic techniques , intubation of the trachea can be difficult or even impossible in such patients . This is why all persons performing tracheal intubation must be familiar with alternative techniques of securing the airway . Use of the flexible fiberoptic bronchoscope and similar devices has become among the preferred techniques in the management of such cases . However , these devices require a different skill set than that employed for conventional laryngoscopy and are expensive to purchase , maintain and repair . 
