Upper

Airway

Paul H. Alfille,

MD,* William E. Hurford, MD”f

The Departments of’ Anesthesia, Medical School, Boston, MA.

*Instructor in Anaesthesia, Harvard ical School. Assistant in Anesthesia, sachusetts General Hospital

MedMas-

tAssistant Professor of Anaesthesia, Harvard Medical School. Assistant Anesthetist, Massachusetts General Hospital Address reprint requests to Dr. Hurford at the Department of Anesthesia, Massachusetts General Hospital, 32 Fruit Street, BOSton, Massachusetts 02114, USA. Received for publication November 29, 1990; revised manuscript accepted for publication December 18, 1990. 0 1991 Butter-worth-Heinemann

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Injuries

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Hospital and Harvard

The management of a patient with an upper airway injury can test the skills of the best anesthesiologist. At one extreme, the airway may be obviously disrupted, occluded, or exposed. At the other, there may be no clue that an airway injury has occurred. Concerns for cervical spine injury and the presence of major vascular or esophageal injuries complicate the evaluation and management of these patients. The literature provides little guidance. Prospective studies of traumatic upper airway injury are difficult because their occurrence is rare and the insult is so variable. In this issue of the Journul of Clinical Anesthesia, R.S. Cicala and his coworkers’ present 46 cases of recognized upper airway injury seen over four years at their institution. The data were gathered retrospectively and reflect the population, referral patterns, and pre-hospital care of their region. Diagnostic techniques and treatments were not randomized. The investigators did not test any particular hypothesis; they just treated their patients to the best of their ability. But, there is a wealth of information in their report. Stabbing, gunshots, and blunt trauma caused the injuries. Diagnosis and airway management were relatively easy in the stabbing victims. In all but one case, stab wound victims had clear openings into the airway (5 of 9 cases) and/or subcutaneous emphysema (8 of 9 cases). The remaining victim had an occult airway penetration diagnosed by bronchoscopy. Four of the patients were intubated directly through the airway defect. No patient required emergent tracheotomy to secure the airway, and deaths were due to non-airway causes (exsanguination) rather than difficulties in airway management. While the diagnosis was also straightforward in patients suffering gunshot wounds, airway management was more complicated. Of the 17 gunshot victims reviewed, 4 had open airway wounds, 9 had subcutaneous air on lateral cervical spine radiographs, and 2 had tension pneumothoraces. Airway management was more difficult in these cases. Two patients required emergent tracheotomy following failed attempts at awake endotracheal intubation. A ‘7-minute delay occurred before an airway was finally established via tracheotomy in another patient, and a fourth was never successfully ventilated due to a distal tracheal injury. Airway injuries resulting from blunt trauma were the most challenging. Of these, cricoid fractures were the most difficult to diagnose and potentially the most dangerous. Only one of the three cricoid fractures was diagnosed (by subcutaneous emphysema). The other two fractures were

J. Clin. Anesth., vol. 3, March/April 1991

Editorial

unsuspected prior to the induction of general anesthesia for laparotomy. Cricoid pressure or attempted nasotracheal intubation produced complete airway obstruction requiring tracheotomy, which wa:, :msuccessful in one of the cases. Two early deaths occurred following t mt injury. In both cases, emergent tracheotomy failed because the distal trachea could not be reached through the tracheotomy incision. Five other patients with airway injuries from blunt trauma required emergent tracheotomy after attempted awake endotracheal intubation failed. Overall, eight o: the 20 patients (40%) with blunt injuries required emergent tracheotomy. The study by Cicala and coworkers’ confirms that many patients with upper airway injuries may be successfully managed using traditional techniques to establish an airway. Three-fourths of the patients (35146) had no apparent airway management problems and were either observed without being intubated (four patients), intubated through an obvious airway defect (six patients), or endotracheally intubated (25 patients). The remaining patients were not so lucky and required emergent tracheotomy, most commonly following blunt injuries. Attempts at intubation in patients with unsuspected cricoid injuries following blunt trauma were disastrous. When the cricoid cartilage is fractured, cricoid pressure or the attempted passage of an endotracheal tube may dislocate the cricoid and/or entirely disrupt the trachea. Consequently, an extremely high index of suspicion for cricoid injury is necessary in cases of blunt upper airway trauma. Even if the patient is stable and endotracheal intubation is planned, the equipment and personnel required to perform an imme’diate tracheotomy must be present. A “rapid sequence” intubation may result in rapid loss of the airway and is usually contraindicated. Under the best of circumstances, ample pre-oxygenation followed by awake flexible bronchoscopic evaluation and intubation may be chosen. In this way, it may be possible to safely thread an endotracheal tube through disrupted areas. Prior induction of general anesthesia, using a potent inhalation anesthetic and maintaining spontaneous ventilation, may also be appropriate in some patients. This approach is used frequently at our institution to secure the precarious airway in non-emergent cases. Rigid laryngoscopy and bronchoscopy may also be performed and used to successfully secure the airway after the induction of general anesthesia. If the airway is lost, or attempted endotracheal intubation appears unwise and the patient is unstable, immediate tracheotomy is the only appropriate choice. When the trachea itself is injured, the tracheotomy should be placed through the damaged area, if possible. Conservation of normal trachea is imperative, since ultimately the trachea will require surgical repair.’ In some patients, the airway injury may not be immediately apparent. Ten of the 46 patients with upper airway injuries in the series studied by Cicala and coworkers’ were not diagnosed by presenting signs and symptoms. Five were diagnosed by computed tomography, one by laryngoscopy, one by bronchoscopy, two during the induction of anesth’esia, and one only by autopsy. Others may have remained undetected for weeks.2 These patients may present later with signs and symptoms of airway disruption, tracheal stenosis, vocal cord paralysis, or laryngeal dysfunction. In some cases, airway problems may become apparent only after cicatrization and stenosis develop, or when general anesthesia and endotracheal intubation are attempted prior to subsequent operative procedures. We must remain suspicious. The diagnosis and management of upper airway injuries, especially those following blunt trauma, remain problematic. Should all stable paJ. Clin. Anesth.,

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Editorial tients undergo computed tomography or bronchoscopy to exclude occult injuries? Are there associated injuries or signs in patients with occult airway injuries following blunt trauma ? How frequently do late complications occur? Should all patients with severe injuries receive an immediate tracheotomy, or are bronchoscopic intubations appropriate for some patients? Future studies of upper airway injuries should address such specific diagnostic and management techniques but admittedly may be difficult, if not impossible, to perform. Until then, retrospective studies, such as the one by Cicala and co-workers in this issue, remain valuable and can supplement our own clinical experiences.

References 1. Cicala RS, Kudsk

KA, Butts A, Nguyen H, Fabian TC: Initial evaluation and management of upper airway injuries in trauma patients. J C/in An& 1991; 3: 91-98. 2. Mathisen DJ, Grillo H: Laryngotracheal trauma. Ann Thorac Surg 1987; 43: 254-262.

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1991

Upper airway injuries.

Upper Airway Paul H. Alfille, MD,* William E. Hurford, MD”f The Departments of’ Anesthesia, Medical School, Boston, MA. *Instructor in Anaesthesi...
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