Definitive Treatment

Definitive treatment of TIF has traditionally involved median sternotomy and ligation of the innominate artery. More recently management has involved endovascular stenting of the innominate artery. This may be via a right brachial artery approach to cover the fistula point and avoid the entrance of the common carotid artery.⁹ Experience with endovascular stenting has been limited, and the rate of endo leak associated with the procedure has been cited as 25 percent, with 50 percent mortality in those requiring bleeding control procedures.^15,19 Endovascular intervention depends upon the patient’s hemodynamic stability and availability of interventional radiology.

Bleeding control may involve a right supraclavicular incision/median sternotomy to expose the innominate artery, the right common carotid artery, right subclavian artery and the trachea, and reconstruct the vessel, using vascular clamps to control the bleeding.

Surgery may also entail ligation or resection of the artery with replacement by a vascular prosthesis, carefully maintaining continuity between the right common carotid and the subclavian artery, and placement of a sternocleidomastoid flap, adipose or thymus tissue to cover suture and tracheal defects.20 Reverse saphenous graft has also been employed to produce aorto-carotid and aorto-subclavian anastomoses.²¹ The tracheal defect may be left adherent to the innominate artery or closed with a pericardial patch.⁴

Complications

Mortality of TIF has been reported to be above 50 percent, and approaching 100 percent if untreated. Fatal outcomes postoperatively may be due to re-bleeding after attempts to preserve flow in the innominate artery or using sutures or prosthetic material in an infected area.22,23 Ligation of the innominate artery is associated with a risk of brain ischemia and ischemia of the right upper extremity.

The high mortality post-operatively may be related to difficulty in controlling hemorrhage, high infection rates, or other comorbid conditions.²⁴ The fistula is an unclean wound, so that insertion of a stent carries a risk of wound infection. On the other hand, the procedure can be performed under local anesthesia and on an unstable patient. Innominate artery transection also poses a risk of infection such as sternal osteomyelitis after sternotomy—generally required for innominate artery transection—since the surgical field is not aseptic.²⁵

Neurologic deficits have been reported in 10 percent, and sternal wound complications in 39 percent. Many of these patients have preexisting neurologic deficits. Occlusion of the right carotid or right subclavian artery may lead to steal syndrome.²⁶

Conclusion

The incidence of late onset TIF is likely to increase as treatment for patients with severe neuromuscular disorders improves, and these patients’ life expectancy increase. The emergency physician must be prepared to intervene to stabilize these patients and route them to definitve care.