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Tracheobronchial Thrombus in a Combat Wounded Patient With a New Tracheostomy

2020; Lippincott Williams & Wilkins; Volume: 27; Issue: 3 Linguagem: Inglês

10.1097/lbr.0000000000000680

1944-6586

Michael D. Stockin, Jordan Lane, William Londeree, Bryan D. Laliberte,

Trauma Management and Diagnosis

CASE REPORT A 29-year-old previously healthy man was emergently evaluated at bedside in the intensive care unit for tracheostomy site hemorrhage. The patient was postoperative day 4 from an uncomplicated percutaneous tracheostomy placement for prolonged mechanical ventilation. His medical history included multiple injuries from an improvised explosive device attack in Afghanistan 16 days prior. Complications of this event included a right frontoparietal stroke, right carotid pseudoaneurysm status post covered stenting, multiple facial lacerations, and bilateral pneumothoraces. The preoperative physical examination revealed an athletic 118 kg male who was ventilated by tracheostomy. Over 500 mL of blood had been suctioned from the airway despite attempts to control hemorrhage with manual pressure. The surgeon was at bedside packing the bleeding site with topical cellulose hemostat and topical thrombin. The patient was emergently taken to the operating room where he received a general anesthetic and was placed on pressure control ventilation with 100% FIO2. Direct laryngoscopy was performed with a Macintosh 4 blade. An 8-mm endotracheal tube (ETT) was advanced 24 cm at the teeth without difficulty before removal of the tracheostomy tube. Progressively increased positive airway pressures were noted by the anesthesia team. The patient was switched to manual bag-mask ventilation. A standard 15-Fr flexible diagnostic bronchoscope was advanced through the ETT. A large blood clot was identified at the carina with near complete occlusion of the left main stem and ∼50% occlusion of the right (Fig. 1). Attempts at removal with saline irrigation and bronchoscope suctioning were unsuccessful. The surgical team attempted to extract the thrombus with Yankauer suction and manual graspers as well.FIGURE 1: Flexible bronchoscopic image of carina with thrombus.The ETT was repositioned in order to provide access for the surgeons to remove the clot through the stoma. However, this process was paused intermittently in order to advance the ETT and improve delivery of oxygen. Over the course of 15 minutes, the patient experienced desaturation episodes to a nadir SpO2 of 30%. Oxygen tubing was attached to the bronchoscope in order to provide continuous oxygenation to the right main stem under direct visualization. This stabilized the peripheral saturation to above 90%. The surgical team was eventually able to remove the clot with use of large pean forceps through the tracheostomy site. Significant findings included a large tracheobronchial thrombus (Fig. 2). Hemostasis of bleeding at the tracheostomy site was achieved. The patient was returned to the intensive care unit intubated and stable. He experienced a full postoperative recovery and eventually was discharged to a subacute rehabilitation hospital.FIGURE 2: Tracheobronchial thrombus after extraction. Measuring tape is 8 cm.DISCUSSION Tracheostomies are commonly performed in critical care patients for prolonged airway management.1 Owing to the vascularity of the neck, one of the most serious postoperative complications is hemorrhage. A Cochrane review of 10 studies found that the incidence of major bleeding within 24 hours of surgery was 8% for surgical tracheostomies and 5.6% for percutaneous tracheostomies.2 Approximately 18.5% of perioperative deaths in tracheostomy patients involve hemorrhage.3 Apart from immediate bleeding, the complication of delayed major vessel hemorrhage has long been a known complication of tracheostomy, occurring in 1% of open cases.4 Erosion of the innominate artery is the most common reason for massive hemorrhage with an incidence of 0.6% to 0.7% of all tracheostomies.5 Although delayed hemorrhages have been reported to occur as early as 30 hours following tracheostomy, the peak incidence is between postoperative days 7 through 14.5 Currently accepted practice is to treat any bleeding incident occurring >3 days after tracheostomy placement as a “sentinel” or “herald” bleed from a tracheoinnominate fistula.6 Preparations should be made to undergo thoracotomy if necessary to control blood loss.6 In a review of 19 delayed massive hemorrhages following open tracheostomy, over 94% of patients died.7 A single sentinel bleed between postoperative day 8 to 7 months foretold imminent terminal exsanguination in all cases.7 A review of over 497 percutaneous dilatational tracheostomies identified the primary cause of immediate postprocedural hemorrhage to be stomal granulation tissue.8 Other vascular anomalies may cause tracheostomy placement complications including an aberrant anterior jugular communicating vein, a high left brachiocephalic vein, or high inferior thyroid vein.8 In this case, surgical site granulation tissue was ultimately determined to be the likely source of bleeding. Tracheobronchial clot formation is a rare, but life-threatening complication that can be difficult to recognize. Its appearance may resemble other causes of acute airway obstruction. Principal signs may include a sudden increase in peak airway pressures, decreased chest wall motion, increased end-tidal carbon dioxide level, and decreased peripheral oxygen saturation from compromised gas exchange. Late findings include arrhythmia, systemic hypotension, and cardiovascular collapse.9 Oftentimes tracheobronchial thrombus is a diagnosis that is made on autopsy. Mortality rates are exceedingly high and likely >50% based on reported cases.9 Treatment of a suspected tracheobronchial thrombus can be challenging. Factors contributing to this include difficult ventilation and competition for the airway with the surgical team. Acute airway obstruction requires the concurrent pulmonary management, support of circulation, and removal of pathology. This requires flexibility and a team approach. Immediate actions to be taken should include informing the surgeon, summoning help, and switching to manual respirations with 100% FIO2. If available, the perfusionist should be alerted to the potential need for cardiopulmonary bypass or extracorporeal membrane oxygenation.9 Ventilation may fail without novel approaches including jet ventilation or oxygenation through the bronchoscope under direct visualization. Rigid bronchoscopy is a viable alternative to assist in ventilation.10 In this situation, the tracheobronchial cast was only discovered when flexible bronchoscopy was performed deep into the respiratory tree. This allowed for early identification as the thrombus rapidly expanded. Jet ventilation through rigid bronchoscopy would be a viable alternative if readily available.10 Other interventional techniques include use of a cryoprobe introduced through the working channel of a bronchoscope.11 The mechanism of action is to adhere the clot to the probe by freezing.12 Cryoextraction can be applied to foreign bodies that are difficult to remove with standard working channel graspers, including blood clots. This technique has been demonstrated to be successful.13 In this clinical case, the serrated jaws of the pean forceps were of adequate length to reach deep into the patient’s neck through the stoma. Aspirin could have contributed to bleeding through the surgical site in this medically complex patient. However, antiplatelet agents are indicated to maintain carotid stent patency, which stabilized cerebrovascular circulation. Use of topical hemostatic agents could have contributed to the formation of clot. However, in the setting of a bedside hemorrhage, it was warranted to ensure hemodynamic stability before emergent surgical exploration. This hemorrhage was presumed to be a tracheoinnominate fistula until disproven in the surgical theater. CONCLUSIONS Tracheobronchial thrombus is a rare but treatable condition. Our case report highlights the need for continued vigilance of this potentially catastrophic complication of airway hemorrhage. Current management strategies available to the medical team are limited to providing support as a bridge to manual extraction. Unless a prompt diagnosis is made, mortality is high.