Asian Cardiovasc Thorac Ann 2006;14:514-516
© 2006 Asia Publishing EXchange Ltd
Tracheo-innominate Artery Fistula in Children with High-Lying Innominate Artery
Voravit Chittithavorn, MD,
Chareonkiat Rergkliang, MD,
Apirak Chetpaophan, MD,
Prasert Vasinanukorn, MD
Division of Cardiovascular Thoracic Surgery, Department of Surgery, Songklanagarind Hospital, Songkla, Thailand
For reprint information contact: Voravit Chittithavorn, MD Tel: 66 74 451 401 Fax: 66 74 429 384 Email: Cvoravit{at}medicine.psu.ac.th, Division of Cardiovascular Thoracic Surgery, Department of Surgery, Faculty of Medicine, Songklanagarind Hospital, Prince of Songkla University, Hatyai, Songkla 90110, Thailand.
 |
ABSTRACT
|
|---|
Tracheo-innominate artery fistula (TIF) is an uncommon but frequently fatal complication of tracheostomy. Significant airway hemorrhage usually occurs after premonitory bleeding. When massive bleeding occurs, immediate control of arterial bleeding, control of the airway and subsequent definite treatment are the principles for saving lives. Without prompt surgical intervention, the outcome of this complication is grave. Physicians should maintain a high index of suspicion of TIF in any patient with a recent tracheostomy and subsequent tracheal hemorrhage.
|
INTRODUCTION
|
|---|
Tracheo-innominate artery fistula (TIF) results from full-thickness erosion of the anterior wall of the trachea extending into the adjacent innominate arterial wall.1 It is a catastrophic and often fatal complication in tracheostomy patients. Jones et al noted that 78% of patients who develop TIF frequently bleed within 21 days of establishing the tracheostomy.2 The survival rate in patients who develop bleeding from a TIF has been reported as 14.3%, and only patients who received immediate surgical intervention survive.3 The proposed mechanism of TIF formation is mucosal necrosis due to constant pressure by the elbow, tip or cuff of the tracheostomy tube on the anterior wall of the trachea, resulting in erosion extending into the adjacent arterial wall. The presence of a high-lying innominate artery predisposes patients to a high risk of developing TIF, particularly in children and young adults.3 A significant clinical presentation of TIF is premonitory bleeding, often not life-threatening but which may precede massive bleeding. Herein we present a patient with a high-lying innominate artery, who developed a TIF as a catastrophic complication of tracheostomy, after a normally placed tracheostomy tube.
|
CASE REPORT
|
|---|
A 2-year-old boy who had been endotracheally intubated for ventilation assistance as a sequelae to aspiration of corn seeds, was admitted with premonitory bleeding from the tracheostomy tube 52 days after the tracheostomy. The patient was bed-ridden as a result of spastic cerebral palsy resulting from prolonged brain anoxia during the corn seed aspiration. His Glasgow Coma Scale (GCS) was E1V1M4. As his breathing was dependent on mechanical ventilation, a tracheostomy was performed and a low-pressure size 5 cuffed tracheostomy tube was correctly placed. On postoperative day 52, a transient tracheal hemorrhage occurred. Fiberoptic bronchoscopy was performed under general anesthesia which confirmed suspicions of TIF by visualization of severe tracheitis and initiation of massive bleeding from the trachea after removal of a blood clot. The trachea cuff was hyperinflated, however there was no success in controlling the bleeding. The tracheostomy wound was widely opened and the bleeding was successfully controlled by digital compression. During a 5 minute interval, the patient lost approximately 800 mL of blood and became severely hypotensive. After being hemodynamically stabilized, a standard median sternotomy was performed. The innominate vein and artery were dissected. A fistulous tract was identified in the mid portion of the high-lying innominate artery at a level above the tracheal balloon (Figure 1
). There was no significant evidence of previous local tissue infection.
View larger version (132K):
[in this window]
[in a new window]
|
Figure 1. The arrow points to a fistulous tract between the third and fourth tracheal ring and the high-lying innominate artery. (A: innominate artery; B: innominate vein; C: tracheal wall.)
|
|
The innominate artery, right subclavian artery and right common carotid artery were controlled proximally and distally. A defect of 5 mm in size was revealed on the posterior wall of the high-lying innominate artery. The defective segment of the innominate artery was resected and the vessel ends oversewn with monofilament nonabsorbable sutures (Figure 2). The right subclavian artery was ligated 5 mm distal to the carotid-subclavian bifurcation to prevent retrograde blood flow from the carotid artery into the subclavian artery. The soft tissue was interposed over the tracheal defect. An endotracheal tube was inserted distal to the tracheal defect. Histopathologic examination of the fistula revealed necrosis at the tracheal opening which suggested a necrotic ischemic process, which commenced at the trachea and progressed towards the innominate artery. The patient maintained the same Glasgow Coma Score as preoperatively. The patient was in the Pediatric Intensive Care Unit for 14 days, and extubation was performed on day 13. He was hospitalized for an additional three weeks for chest physiotherapy. At follow-up 10 months after the incident there was no evidence of tracheal stenosis.
View larger version (145K):
[in this window]
[in a new window]
|
Figure 2. The two arrows indicate the oversewn divided ends of the innominate artery. (A) Represents the tracheal wall defect after limited debridement above the level of the tracheal cuff ; (B) Innominate vein.
|
|
|
DISCUSSION
|
|---|
Tracheo-innominate artery fistula is a life-threatening complication of tracheostomy that usually presents with acute and massive tracheal bleeding. It is a rare complication occurring in less than 1% of tracheostomies.3 The most common cause of TIF is erosion following low level placement of the tracheostomy stoma, allowing the cannula to abut and erode the concave surface of the innominate artery. The innominate artery has a close anatomical relationship with the trachea and usually traverses the trachea at the level of the fifth or sixth tracheal ring behind the manubrium,4 however that may vary between the sixth and the thirteenth tracheal ring.4 Accordingly, this complication may be caused by creation of the tracheostomy stoma at a level lower than the fourth tracheal ring.2,4
Generally, an opportunity to develop TIF can be avoided when the tracheostomy is placed in an appropriate position at the level of the second or third tracheal ring rather than at the level of the sternal notch.3,4 The tracheas of children and young adults are mobile and rise up into the neck along with the innominate artery, on hyperextension. A high-lying innominate artery is an anatomically rarely positioned artery, higher than normal, in relation to the trachea. It has been reasonably accepted that it may traverse above the fourth tracheal ring or sternal notch,5 especially in children.3 The incidence of high-lying innominate artery has been reported to be up to 12%.5 Even normally placed tracheostomy tubes, as in our case, may occasionally erode the innominate artery with subsequent fistula formation.2 In this case, we found a high-lying innominate artery traversing the trachea at the level of the third to fourth tracheal ring. The innominate artery in this case originated from the aortic arch on the right side of the trachea, which is the normal origin of the innominate artery. Consequently high localization of an aberrant innominate artery was not implied. As a result of the tracheal mucosa’s intolerance to constant pressure, the tracheal mucosa is usually injured after 48 hours of constant pressure. Tracheal capillary pressure normally ranges between 20 and 30 mm Hg.6 In human studies, tracheal mucosal blood flow is impaired at a pressure of 22 to 24 mm Hg and is totally obstructed at 35 to 37 mm Hg.6 To avoid mucosal pressure necrosis, the use of a low pressure cuffed tracheal tube inflated to less than 20 mm Hg is recommended.6
If massive bleeding occurs, management involves three simultaneous priorities: maintenance of a patent airway, control of bleeding and basic cardiopulmonary resuscitation. As a first step, tracheostomy cuff hyperinflation may temporarily control the bleeding. However, immediate surgical correction is the only life-saving procedure.1 The operation of choice is resection of the innominate artery in contact with the tracheal erosion and suture of the divided ends. The important principles in prevention of infection and breakdown of arterial repair include: (1) suture of healthy arterial wall, (2) use of monofilament suture, (3) excision of an adequate portion of the artery so that the suture lines are not in approximation with the site of erosion, and (4) control of infection by drainage and antibiotics.2
As a result of changes in the pressure gradient between the circle of Willis, the right common carotid artery and the distal subclavian artery after division of the innominate artery, retrograde blood flow from the carotid artery into the subclavian artery may occur as a carotid-subclavian steal phenomenon. Therefore, in this case, we ligated the right subclavian artery in order to avoid a possible cerebral steal phenomenon.2 Division of the innominate artery carries significant risk of neurologic sequelae in approximately 10% of cases.7 Although some surgeons have suggested bypass grafting of the distal innominate artery, the placement of a synthetic graft or autograft in this contaminated area can increase the possibility of secondary bleeding.7,8 Most surgeons therefore advise resection of the artery without using a vascular bypass graft.8 The mortality rate of TIF, if not surgically treated, approaches 100%.2 However, in correctly resuscitated patients, 25% of those patients will survive this complication.2
|
CONCLUSION
|
|---|
In children and young adults with suspected TIF, presence of a high-lying innominate artery should be considered as a possible predisposing factor for this complication. The most important considerations in the prevention of TIF formation are proper surgical techniques and the careful management of the post-tracheostomy patient. Until now, awareness, with a high index of suspicion of TIF and proper steps in prompt surgical management of the confirmed TIF patient, is the optimal way to ensure survival after this catastrophic complication.
|
REFERENCES
|
|---|
- Wright CD. Management of tracheoinnominate artery fistula. Chest Surg Clin N Am 1996;6:865–73.[Medline]
- Jones JW, Reynolds M, Hewitt RL, Drapanas T. Tracheo-innominate artery erosion: Successful surgical management of a devastating complication. Ann Surg 1976;184:194–204.[Medline]
- Wood DE, Mathisen DJ. Late complications of tracheotomy. Clin Chest Med 1991;12:597–609.[Medline]
- Oshinsky AE, Rubin JS, Gwozdz CS. The anatomical basis for post-tracheotomy innominate artery rupture. Laryngoscope 1988;98:1061–4.[Medline]
- Wind G, Valentine R. Anatomic exposures in vascular surgery. Williams & Wilkins, 1991;450.
- Cooper JD, Grillo HC. The evolution of tracheal injury due to ventilatory assistance through cuffed tubes: a pathologic study. Ann Surg 1969;169:334–8.[Medline]
- Melliere D, Becquemin JP, Benyahia NE, Ecollan P, Fitoussi M. Atherosclerotic disease of the innominate artery: current management and results. J Cardiovasc Surg (Torino) 1992;33:319–23.[Medline]
- Deslauriers J, Ginsberg RJ, Nelems JM, Pearson FG. Innominate artery fistula. A major complication of tracheal surgery. Ann Thorac Surg 1975;20:671–7.[Abstract]
TOP
ABSTRACT
INTRODUCTION
