Abstract
Innominate arterial wall rupture with pseudoaneurysm formation was found during angiography in a 39-year-old woman 2 days after she had undergone percutaneous dilatational tracheostomy. Endovascular stent surgery and balloon angioplasty were performed but these procedures failed to control the massive bleeding resulting from an endoleak. We report the clinical presentations and describe the treatment of a tracheo-innominate artery fistula in our patient. We also reviewed the algorithms of management and the rescue options for treating a tracheo-innominate artery fistula.
Keywords
fistula; innominate artery; postoperative complications; stents; tracheostomy;
1. Introduction
The innominate artery originates first from the aortic arch and as it progresses, it branches off into the right common carotid and right subclavian arteries. The innominate artery commonly crosses the trachea at the level of the 9th tracheal ring but the crossover point can vary anywhere between the 6th and 13th tracheal rings. Tracheo-innominate artery fistula (TIF) formation is a fatal complication of percutaneous dilatational tracheostomy with peak incidence occurring 7−14 days postoperatively. The overall incidence is 0.1−1% after surgical tracheostomy.1,2
Erosion and rupture of the innominate artery can be caused by a myriad of events, such as pressure necrosis due to high cuff pressure, mucosal trauma caused by a malpositioned cannula tip, low tracheal incision, a high lying innominate artery and prolonged intubation.3 The mortality rate associated with TIF is as high as 90%.4
We report a case of TIF formation following percutaneous dilatational tracheostomy. Although endovascular repair provided temporary symptom relief, regrettably an endoleak with massive bleeding occurred later and the patient sustained cardiac arrest and died. In our opinion, although an immediate endovascular procedure after diagnostic angiography may be an option for managing TIF, immediate surgical intervention stands out as the supreme choice among other options and should be seriously considered.
2. Case Report
A 39-year-old woman presented with a history of progressive weakness of the right limb and unstable gait for several months. Magnetic resonance imaging revealed the presence of a large meningioma (45 x 45 mm) located in the right supraclival region at the skull base. The patient underwent surgery for tumor resection; however, only a part of the tumor could be removed because of the difficult approach and tumor invasion.
One week later, a ventricle-peritoneal shunt was performed to reduce increasing intracranial pressure. Percutaneous dilatational tracheostomy was performed 15 days after the partial tumor resection. Acute bleeding at the tracheostomy site accompanied by oxygen desaturation, bradycardia, and hypotension was noted 2 days later. Oral endotracheal intubation was immediately performed, followed by local compression with epinephrine-containing gauzes and administration of inotropic agents. Emer gency angiography revealed no active bleeding focus. However, massive bleeding from deeper wounds was noted the next day, and innominate artery injury was highly suspected. Angiography revealed a rupture of the innominate arterial wall with formation of a pseudoaneurysm (Figure 1A). The ruptured vessel wall was sealed up and reconstructed by inserting two Wallgraft stents (Carotid Wallstent™ Monorail™; Boston Scientific Corporation, Natick, MA, USA) within the innominate artery in an overlapping manner to occlude the pseudoaneurysm.
Angiography performed after the procedure revealed no extravasation of contrast medium (Figure 1B), and the patient was sent to the intensive care unit with stable vital signs. However, 18 hours later, the patient sustained massive active bleeding with blood pouring out from the oral and nasal cavities, and from the endotracheal tube. An endoleak was suspected. Angiography was performed and revealed extravasation. An angioplasty balloon catheter was inserted into the innominate artery for embolization but it failed to seal the endoleak (Figure 2). Thereafter, hemodynamic instability persisted and cardiac arrest soon followed. Despite all resuscitation attempts, she succumbed to the massive hemorrhage.
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3. Discussion
After tracheostomy, TIF may develop especially when tracheal hemorrhage occurs 3 days to 6 weeks after the procedure.4 To prevent the development of TIF, prolonged or excessive hyperextension of the neck should be avoided, especially in patients with a tra cheostomy after neurosurgery or head injury.5,6 Although uncommon, formations of TIF, tracheoesophageal fistula and tracheo-subclavian artery fistula are known complications of tracheostomy.7
Anesthesiologists may be involved in the process of managing TIF. From the viewpoint of anesthesiologists, airway protection has the priority over other measures in primary management. Placement of an oral endotracheal tube is necessary for airway protection and in subsequent diagnostic or surgical procedures for managing TIF. In our patient, besides maximally inflating the cuff of the tracheostomy tube, an oral endotracheal tube was immediately inserted to provide better airway protection followed by digital compression with pressure packing to control the bleeding, after which her vital signs became stable. Various management algorithms of TIF have been proposed.3,8,9 In summary, overinflating the cuff of the tracheostomy tube is the first step. Successive steps including pressure packing, endotracheal intubation, digital compression via the stoma and overinflation of an endotracheal cuff are the keys for temporarily stopping continuous bleeding. Control of bleeding should precede surgical exploration and repair of TIF.
Angiography is not recommended as the initial diagnostic means for the detection of TIF.10,11 However, angiography has recently been shown to provide excellent images for confirming the extent of TIF and, therefore, it is able to definitively diagnose TIF. In addition, there are endovascular procedures for repair of TIF that provide phy sicians with therapeutic options other than conventional surgical intervention in selected circumstances.12−14 There fore, understanding endovascular procedures and the incidental risks are important and may be helpful in managing such a catastrophic complication.
Endovascular embolization and stent grafts have been reported to be successful treatment options for innominate artery injuries.13,15,16 In hemodynamically stable patients, endovascular stenting is the treat ment of choice for traumatic aortic rup ture.17,18 However, to the best of our knowledge, the success rate of immediate endovascular repair in managing TIF has not been reported. Furthermore, endovascular stents can become infected and/or erode the trachea12 and the success of endovascular procedures depends on the operator’s expertise, the durability of the graft and the site of TIF. In general, temporary endovascular stenting may be less invasive and more expeditious than surgical exploration, but not a guarantee for elimination of TIF. In our patient, endoleak resulting in massive bleeding took place after endovascular stenting and the tearing of the innominate artery hindered endovascular embolization. In such a situation, immediate surgical intervention has been recommended to prevent a disastrous outcome.19
In conclusion, we believe that immediate endovascular repair after diagnostic angiography is a therapeutic option in managing TIF. However, immediate surgical intervention should also seriously be taken into consideration whenever endovascular procedures fail, and therefore the treatment should be individualized.