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Airway ®re due to diathermy during tracheostomy S. A. Rogers,1* K. G. Mills2 and Z. Tufail31 Specialist Registrar, 2 Consultant, Department of Anaesthesia and Intensive Care, and 3 Specialist Registrar, Department of Cardiothoracic Surgery, The Cardiothoracic Centre, Liverpool, UK We describe a case of airway ®re in an 83-year-old, critically ill patient. The ®re occurred during a surgical tracheostomy under general anaesthesia, following ignition of the tracheal tube by diathermy. After debridement of the burnt tissue and treatment with intravenous antibiotics and glucocorticoids, the patient's respiratory function worsened initially. The patient eventually recovered without long-term sequelae and was discharged from the intensive care unit. The circumstances of this and other similar incidents are reviewed, as are the suggested methods for preventing this frightening occurrence.
Keywords Airway ®re: tracheostomy; diathermy.
* Present address: Department of Anaesthesia and Intensive Care, University Hospital Aintree, Lower Lane, Liverpool L9 7AL, UK.
Accepted: 2 November 1999 Fires in the operating theatre are seen as mostly of On the afternoon of the operation, he was transferred historical interest, dating back to the era of ether and from the intensive care unit (ICU) to the main operating cyclopropane anaesthesia. Recent interest in airway ®res theatre. The patient was ventilated with iso¯urane in 100% has mostly centred on the use of lasers in laryngeal surgery.
oxygen using the circle system of a Drager Cato anaes- However, ®res caused by diathermy ignition of tracheal thetic machine (Drager Medizintechnik GmbH, Lubeck, tubes are still occasionally reported and may well be under- Germany), and was monitored with electrocardiogram, reported. These incidents have led to both morbidity and pulse oximeter, invasive arterial blood pressure, end tidal mortality; therefore, anaesthetic and surgical techniques carbon dioxide and anaesthetic gas concentrations. The should be modi®ed to reduce their incidence and severity.
surgeon performed a standard collar incision and dissected down to the trachea with scissors, securing haemostasis with coagulating bipolar diathermy. The isthmus of the thyroid did not require division. The surgeon informed An 83-year-old, male intensive care patient was listed for the anaesthetist that he would open the trachea using the a surgical tracheostomy. He had undergone coronary diathermy, and the anaesthetist partially withdrew the artery bypass grafting of four vessels 7 days previously, tracheal tube. As the trachea was opened with the dia- and had remained intubated (with an 8.5-mm internal thermy in coagulation mode, there was a loud noise and diameter Mallinckrodt PVC oral tracheal tube) and venti- ¯ames rushed out of the tracheal stoma during the lated because of respiratory failure and a stroke. He inspiratory phase of ventilation. The circuit was immedi- required 70% oxygen with 2.5 cmH2O positive end- ately disconnected from the tracheal tube and the ®re was expiratory pressure (PEEP), as well as epinephrine and rapidly extinguished with saline. The tracheal tube was dopamine infusions. He had also developed acute renal removed and an 8-mm Portex tracheostomy tube was inserted into the trachea without dif®culty. The patient did not become hypoxaemic or suffer any systemic distur- After the ®rst 48 h, the patient's condition improved and bance. A small area of burnt subcutaneous tissue around he was discharged from the ICU to a general ward 26 days the stoma was debrided. No muscle or deeper burn could later with the tracheostomy tube in place. The patient was be seen. Examination of the tracheal tube showed that uneventfully decannulated a few days later and was trans- it had been ignited and extensively burnt (Fig. 1) around ferred to his local hospital for further care 14 days after his the cuff. Although it was quite deformed, it had remained discharge from the ICU. He eventually took his own discharge 100 days after the airway ®re. At a follow-up A bronchoscopy via the new tracheostomy was per- cardiac surgery clinic 2 weeks later he was in good health.
formed. A possible small area of super®cial burn was observed on the posterio-lateral surface of the trachea, but no other burns or signs of inhalational injury were seen. On direct laryngoscopy, no oral or laryngeal burns Surgical tracheostomy is a commonly performed opera- were seen. After consultation with a senior thoracic tion that is undertaken by a number of surgical specialties surgeon, dexamethasone 4 mg was given intravenously.
[1]. It is also frequently required in critically ill patients.
The operation was completed without further problems Although large retrospective studies suggest that the mor- and the patient was transferred back to the ICU. Over the bidity and mortality of the operation have been decreasing next 48 h, his oxygen requirement increased to 100%. He for some years [1], there are still many short- and long- required neuromuscular blocking agents to facilitate ven- tilation and he developed copious secretions from his Ignition of the tracheal tube by diathermy (or electro- lungs. After discussion, no further doses of dexamethasone cautery, electrosurgery) during surgical tracheostomy is were given. A further bronchoscopy showed normal reported occasionally [2±7]. Its incidence is impossible to trachea and bronchi and no signi®cant thermal injury.
determine [8], but, even though it is rare, laryngotracheal burns following such a ®re may have contributed to a The classical triad needed for a ®re or explosion (fuel, energy and oxidising sources) are all present during surgi- cal tracheostomy. Possible fuel sources include the tracheal tube (usually made of PVC), charred tissue, suture mate- rial, drapes and antiseptic alcohol solutions [2, 4, 9, 10].
Diathermy delivers an energy source that generates tip temperatures in excess of 910 8C (1500 8F) [9] using an alternating sine wave current at frequencies between 20 000 and 50 000 Hz. The cutting mode is continuous, whereas coagulation is intermittent [4, 5, 11]. The oxidis- ing sources are both oxygen and nitrous oxide; the latter being a powerful oxidising agent in its own right [12].
In many of the reported cases, there are several common factors. Many occurred in intensive care patients [2±7] with complex needs, such as high oxygen requirements and poor tolerance of periods of apnoea and loss of PEEP.
These patients have an increased incidence of mortality and morbidity in larger studies of surgical tracheostomy [1, 13]. High oxygen requirements [3, 5, 6], routine pre- oxygenation prior to changing the tracheal tubes [2, 4, 7] and supplementary nitrous oxide [9] were the usual oxidising sources. In several cases [4, 6, 7], including the one reported here and the case that resulted in a fatality [5], the tracheal incision was intentionally made using the diathermy, either in the cutting or coagulation mode.
However, in other cases [2, 3], the tracheal incision was made with a scalpel and the tracheal tube was ignited by Figure 1 The 8.5-mm internal diameter Mallinckrodt PVC oral the diathermy while securing haemostasis. In most of the tracheal tube that was ignited at the cuff and extensively burnt.
cases [2±7], ignition was started by cuff de¯ation causing a high ¯ow leak of oxygen-enriched gas into the surgical assessment of respiratory function on the ICU [4, 7].
®eld, or in the case of oral ®res, a retrograde leak of oxygen However, diathermy use can be avoided completely by into the oral and pharyngeal cavities.
percutaneous dilational tracheostomy, a technique with a In the case reported here, failure to withdraw the tracheal tube suf®ciently and opening the trachea with the diathermy were probably the most important factors.
Previous authors have made various recommendations regarding the prevention of such ®res, which can be 1 Zeitouni AG, Kost KM. Tracheostomy: a retrospective grouped into anaesthetic and surgical considerations.
review of 281 cases. Journal of Otolaryngology 1994; 23: Anaesthetic considerations include keeping the inspired oxygen concentration just high enough to allow satisfac- 2 Lim HJ, Miller GM, Rainbird A. Airway ®re during tory arterial oxygen saturation, which may be dif®cult elective tracheostomy. Anaesthesia and Intensive Care 1997; in intensive care patients. However, some authors still recommend the routine use of high oxygen concentrations 3 Bailey MK, Bromley HR, Allison JG, Conroy JM, [2]. Combining oxygen with a non-¯ammable carrier gas, Krzyzaniak W. Electrocautery-induced airway ®re during such as nitrogen or helium, has also been recommended tracheostomy. Anesthesia and Analgesia 1990; 71: 702±4.
[2, 3]. Other manoeuvres include: positioning the tracheal 4 Aly A, McIlwain M, Duncavage J. Electrosurgery-induced cuff either just above the carina or above the operative site, endotracheal tube ignition during tracheotomy. Annals of Otology, Rhinology and Laryngology 1991; 100: 31±3.
®lling the tracheal cuff with saline and packing uncuffed 5 Lew EO, Mittleman RE, Murray D. Endotracheal tube tracheal tubes. Controversy also exists as to which type of ignition by electrocautery during tracheostomy: case report tracheal tube material is best, with PVC being described as with autopsy ®ndings. Journal of Forensic Science 1991; 36: both suitable [2] and unsuitable [3]. The newer generation of laser-resistant tubes may be the best solution [8], but 6 Marsh B, Riley RH. Double-lumen tube ®re during this would entail an additional tube change in critically tracheostomy. Anesthesiology 1992; 76: 480±1.
7 Le Clair J, Gartner S, Halma G. Endotracheal cuff ignited Surgical considerations include: opening the trachea by electrocautery during tracheostomy. Journal of the with a scalpel blade, using a suction catheter to remove American Association of Nurse Anesthetists 1990; 58: 259±61.
oxygen and smoke from the operative ®eld, and fashioning 8 Sosis MB, Braverman B. Prevention of cautery-induced the tracheostomy in stages if there is a large gas leak. Use of airway ®res with special endotracheal tubes. Anesthesia and ¯ame-retardant drapes, swabs and sutures may also be 9 Thompson JW, Colin W, Snowden T, Hengesteg A, helpful, but these are often either expensive or unavailable.
Stocks RMS, Watson SP. Fire in the operating room The most important factor is preventing the diathermy during tracheostomy. Southern Medical Journal 1998; 91: from coming into contact with both a fuel and an oxidis- ing source. This is best achieved by avoiding diathermy 10 Brechtelsbauer PB, Carrol WR, Baker S. Intraoperative ®re altogether. If diathermy is required, recommendations with electrocautery. Otolaryngology ± Head and Neck Surgery include disconnecting the breathing circuit prior to dia- thermy use, covering visible portions of the tracheal tube 11 Hazard Report. Electrosurgical airway ®res still a hot topic.
with saline-soaked pledglets and using bipolar diathermy in the coagulation mode at the lowest effective power 12 Macdonald AG. A short history of ®res and explosions level. The bipolar mode will minimise current leakage to caused by anaesthetic agents. British Journal of Anaesthesia 13 Wease GL, Frikker M, Villalba M, Glover J. Bedside Practice ®re drills may be of bene®t [4, 9], but the most tracheostomy in the intensive care unit. Archives of Surgery important point is that the surgeon and the anaesthetist must work together via good communication. In the event 14 Hill BB, Zweng TN, Maley RH, Charash WE, of a ®re, it is important to assess the entire airway with Toursarkissian B, Kearney PA. Percutaneous dilatational both bronchoscopy and laryngoscopy. Treatment of airway tracheostomy: report of 356 cases. The Journal of Trauma: ®res involves antibiotics, dexamethasone and regular Injury, Infection, and Critical Care 1996; 40: 238±43.

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