2017-18 HSC Section 3 Green Book

Gemma Hogg, et al

Laryngeal Trauma Following Inhalation Injury

the effects from thermal damage, chemical irritation, and hypoxia may be unavoidable at the time of insult, managing the patient correctly from the time of emergency admission can improve the outcome in many cases. On assessment of severe injury, the priority is airway security before edema fully develops. In those endotracheally intubated, failure to improve to a point of extubation within 48 hours should prompt discussion regarding conversion to a surgical tracheostomy. 15 Close outpatient follow-up with early ENT input via a special- ist voice clinic in those who developed fibrosis of the upper airway is vital in order to maximize both voice and exercise tolerance. Patients should also be advised of the iatrogenic trauma risk from future elective surgery so that other forms of intubation, such as laryngeal mask, can instead be considered by the anesthetist. REFERENCES 1. Rong Y, Liu W, Wang C, et al. Temperature distribution in the upper airway after inhalation injury. Burns . 2011;7:1187–1191. 2. You K, Yang H, Kym D, et al. Inhalation injury in burn patients: establishing the link between diagnosis and prognosis. Burns . 2014;8:1470–1475. 3. Rabinowitz PM, Siegel MD. Acute inhalation injury. Clin Chest Med . 2002;4:707–715. 4. Cheng W, Ran Z, Wei L, et al. Pathological changes of the three clinical types of laryngeal burns based on a canine model. Burns . 2014;2:257–267. 5. Casper JK, Clark WR, Kelley RT, et al. Laryngeal and phonatory status after burn/inhalation injury: a long term follow-up study. J Burn Care Rehabil . 2002;23:235–243. 6. Sheridan RL. Recognition and management of hot liquid aspiration in children. Ann Emerg Med . 1996;1:89–91. 7. Einav S, Braverman I, Avital A, et al. Airway burns and atelectasis in an adolescent following aspiration of molten wax. Ann Otol Rhinol Laryngol . 2000;7:687–689. 8. Alpay HC, Kaygusuz I, Karlidag T, et al. Thermal burn of the larynx in an adult following hot water aspiration. Otolaryngol Head Neck Surg . 2008;1:164–165. 9. Huzar TF, Cross JM. Ventilation associated pneumonia in burn patients; a cause or consequence of critical illness? Expert Rev Respir Med. 2011;5:663–673. 10. Robinson L, Miller RH. Smoke inhalation injuries. Am J Otolaryngol . 1986;5:375–380. 11. Petroff PA, Hander EW, Mason ADJ. Ventilatory patterns following burn injury and effect of sulfamylon. J Trauma Acute Care Surg . 1975;15:650–656. 12. Lund T, Goodwin CW, McManus WF, et al. Upper airway sequelae in burn patients requiring endotracheal intubation or tracheostomy. Ann Surg . 1985;201:374–382. 13. Gaissert HA, Lofgren RH, Grillo HC. Upper airway compromise after inhalation injury. Complex strictures of the larynx and trachea and their management. Ann Surg . 1993;218:672–678. 14. Divatia J, Bhowmick K. Complications of endotracheal intubation and other airway management procedures. Indian J Anaesth . 2005;4:308–318. 15. Coln CE, Purdue GF, Hunt JL. Tracheostomy in the young pediatric burn patient. Arch Surg . 1998;133:537–539. 16. Barret JP, Desai MH, Herndon DN. Effects of tracheostomies on infection and airway complications in pediatric burn patients. Burns . 2000;2:190–193. 17. Gandhi SS. Transoral laser surgery for glottis stenosis caused by webs. Oper Tech Otolaryngol Head Neck Surg . 2011;22:146–151. 18. Gaynor EB. Gastroesophageal reflux as an etiologic factor in laryngeal complications of intubation. Laryngoscope . 1988;9:972–979. 19. Riffat F, Palme CE, Vievers D. Endoscopic treatment of glottis stenosis: a report on the safety and efficacy of CO2 laser. J Laryngol Otol . 2012;126:503–505. 20. Eckhauser FE, Billote J, Burke JF, et al. Tracheostomy complicating massive burn injury. A plea for conservatism. Am J Surg . 1974;127:418–423.

advanced stages of subglottic stenosis frequently remain challenging for otolaryngologists. However, various surgical procedures have now evolved to manage them, such as a laryngotracheoplasty with cartilage expansion, partial cricotracheal resection with anastomosis, or a combination of the two. In order to select the correct procedure, it is vital that the stenosis characteristics are clearly noted and that any aryte- noid fixation or other airway pathology is identified on endoscopy. 22 An area of contention is that of the increased potential for pul- monary infections with long-term invasive ventilation. 9 Eckhauser et al quote a sixfold increase with tracheostomies in their study of pulmonary sepsis compared with endotracheal intubation, 20 whereas Barret et al reported a study on 36 burn patients with inhalation injuries concluding that the incidence of pneumonia was not increased in tracheostomized patients. 16 A stepwise approach to the management of inhalation injury is recommended. In those intubated, early consideration of sur- gical tracheostomy is recommended, both to facilitate respiratory weaning and to minimize trauma to the glottis. 15 Once webbing has formed within the glottis, investigative procedures are useful. Three-dimensional imaging and pulmonary function test will both provide a baseline and will provide the clinician with informa- tion to inform a decision for surgical or conservative intervention. 17,19 In those with limited effect on exercise tolerance and a non- functional voice, it is highly recommended that patients are reviewed early in an adult voice clinic for a joint review by a laryngologist and speech therapist. This will help initiate a voice rehabilitation program, with speech therapists focusing on pa- tients’ specific needs enhancing their long-term outcome. Furthermore, this aims to reduce the potential risk of webbing. In the case of reduced exercise tolerance and a non-functional voice, a complex adult airway case conference is advised where the laryngologist, thoracic surgeon, and burn surgeon can discuss the options with the patient. Concerning the long-term management of stenosis, at the la- ryngeal level, this will need treatment depending on the Voice Handicap Index scores and airway compromise. Their stenosis can worsen with time; the time frame for scar contracture in the larynx is highly variable when compared with the skin. It can also be hampered by iatrogenic trauma with further intubation, and this needs to be highlighted to the patient so that intuba- tion such as a laryngeal mask can be considered in the elective scenario. 23 There are two forms of recognized stenosis at the laryngeal level: anterior web and posterior glottis stenosis. In the case of anterior webs, release of web and silastic stent would be the treat- ment of choice. 24,25 Posterior glottis stenosis is much harder to deal with and depends on the degree of stenosis and contrac- ture. Treatment options include balloon dilation, botulinum toxin, or the use of a lateralization suture. 26–28

CONCLUSION Inhalation injury can result in immediate, short-term, and long-term complications within the upper airway. Although

239