22

The incidence of injury to the internal carotid artery (ICA) during endoscopic sinus surgery (ESS) is very low, with only 29 cases been described in the literature.1 Injury during endoscopic skull base surgery, however, is more common with an incidence during pituitary surgery of around 5% and higher in parasellar and post fossa surgery.¹ One of the limitations of endoscopic skull base surgery for tumors involving the carotids has been the ability of the surgeon to be able to endoscopically control and repair major vascular hemorrhage. Major vascular injury has a significant and probably underestimated mortality of 15% and permanent morbidity of 26%.¹ Significant tumor involvement of the major vasculature has in the past been considered a relative contraindication to the endoscopic approach. However, with training courses on animals duplicating the conditions of vascular rupture during surgery,² skills have been developed that allow skull base teams to now tackle such cases.

High Risk Patients

Patients at high risk are those with previous radiotherapy, hormone-secreting pituitary tumors (particularly prolactinomas), and growth hormone–secreting tumors. Acromegalic patients will at times have ectatic carotids often with the tumor in contact or surrounding the carotid.³ Any tumor including meningiomas, clival chordomas, and craniopharyngiomas that contact or envelop the carotids places the patient at higher risk during dissection of the tumor.¹

Management

Surgical Field

A major vascular injury creates the most challenging surgical field possible in endoscopic surgery. The high-volume and high-pressure blood flow quickly contaminates the end of the endoscope leaving the surgeon without a view.⁴ No safe maneuvers can be performed if the surgeon cannot see. It is usually not possible for the surgeon to both obtain a surgical view and perform an effective maneuver if he/she is alone. The two-surgeon approach allows one surgeon to control the bloodstream and direct it away from the endoscope and this allows the second surgeon to obtain sufficient view to perform the maneuvers necessary for achieving hemostasis.⁴ There are several principles for surgical field control. First two large bore (10 French) suctions are needed and, if available, the endoscope should have a lens cleaning system that enables the end of the endoscope to be washed immediately it is contaminated. This means that the endoscope does not be need to be removed to clear the view. The first step is to decide in which nostril to place the endoscope. Usually the bloodstream is directed predominantly into one side of the nose (Fig. 22.1).⁴

This should be assessed and the endoscope should be placed down the opposite nostril. The second surgeon should place the suction down the side of major flow while the primary surgeon places the endoscope and second suction down the opposite nostril. The primary surgeon should push the pedicled septal flap out of the way and clear the nostril of blood ahead of the endoscope. We have found that in these situations the flap floats and if only one suction is used, it quickly becomes blocked as the flap is sucked into the end of the suction and the surgical field is lost. Once the flap is pushed into the nasopharynx the second surgeon can place their large bore suction directly over the bleeding vessels and guide the bloodstream into their suction thereby providing the primary surgeon with the visualization necessary to perform the surgical maneuver for hemostasis (Fig. 22.2). If the endoscope and the suction are placed down the same nostril when this guiding of the bloodstream is attempted, the bloodstream will often track alongside of the suction with immediate soiling of the endoscope and loss of the surgical field (Fig. 22.3).

In the past the first response of surgeons in this very challenging situation was to attempt to pack the bleeding vessel to achieve hemostasis. Raymond et al.5 reviewed 12 cases in which a carotid injury had occurred. In 8 of the 12 the nasal packing resulted in complete occlusion of the internal carotid artery (ICA), 4 had stenosis of the ICA, and 1 patient partial occlusion of the middle cerebral artery as well as the ICA. The authors concluded that overpacking contributed to both the morbidity and mortality of the patients.⁵

In skull base surgery there is often wide exposure of the surgical field with a large amount of brain and associated critical vessels, such as the basilar and brainstem perforators from the circle of Willis, exposed. Packing in this situation can contribute significantly to the morbidity and even mortality of the patient and should only be done on the bleeding vessel alone rather than on the surgical area being operated upon. In our department we have developed an animal model of carotid artery injury and assessed the various materials commonly available for management of a significant vascular injury. These included oxidized cellulose, thrombin-gelatin matrix, and crushed muscle patch. Valentine et al.² showed the only effective agent was crushed muscle, which succeeded in achieving hemostasis in all cases. The other materials did not achieve hemostasis with resultant exsanguination of the animal model. The techniques of using the muscle patch repair is for the muscle to be harvested from either the thigh (usually preprepared in skull base cases for taking of a fascia lata graft) or from the sternomastoid muscle in the neck. A 2 × 1.5 × 1 cm piece of muscle is harvested and then crushed between two metal kidney dishes. The primary surgeon uses a Blakesley forceps to guide the muscle patch toward the bleeding vessel. The second surgeon keeps the surgical field clear by continually guiding the bloodstream up a large bore suction. The suction is hovered just above the site of injury. If the suction gets too close it will suck onto the wall of the vessel and result in loss of the surgical field. These techniques are now taught in our workshops. The sheep animal model of carotid injury is used⁶ with the nasal model to recreate the exact clinical situation with the very challenging surgical field and teach how to maintain the surgical field and be able to place the muscle patch and achieve hemostasis. Such courses are recommended as the skills attained in this way will more effectively allow surgeons faced with this very difficult situation to achieve better outcomes for their patients.

Stay updated, free articles. Join our Telegram channel

Join