Planned extra-anatomic cerebral revascularization for carotid artery ligation.

Cerebral revascularization, using extra-anatomic bypass grafts of autologous saphenous vein, was performed in three patients to prevent or to compensate for ischemic effects of emergency ligation of a carotid artery. These ligations were required after spontaneous disruption of common carotid arteries in patients with previous irradiation and radical head and neck surgery. External-carotid-to-external-carotid cross-over (submandibular) bypass graft was performed once, and ipsilateral axillointernal carotid bypass grafts twice. The role of infection in carotid artery rupture, the unpredictable nature and different mechanisms of cerebral malfunctions after carotid ligation, technical details of extra-anatomic bypass grafts, and anatomic considerations in the prevention of recurrent infection and bleeding are discussed. A planned approach of cerebral revascularization at the time of ligation appears to be preferable to a fortuitous outcome. Neurological disability and death from cerebral ischemia can be prevented by using extraanatomic bypass vein grafts.

Pathological fibrinolysis secondary to pseudoaneurysms.

Pathological fibrinolysis due to pseudoaneurysms was observed in a patient 4 years after aortobifemoral bypass graft. The patient presented with a pulsatile abdominal mass and ischemic changes in the legs. Excessive bleeding from venipuncture sites prompted coagulation screening, which disclosed rapid clot lysis, fibrin split products, and low fibrinogen suggestive of pathological fibrinolysis. Therapy with epsilon amino caproic acid (EACA, Amicar) controlled the coagulopathy, permitting angiography and operation. Resection of the pseudoaneurysms resulted in resolution of the abnormal fibrinolysis. Normally, there is a balance between coagulation and fibrinolysis protecting against excessive bleeding or clotting. Clot itself is a powerful stimulus for the activation of the fibrinolytic system, although many other factors have been shown to initiate and sustain the process. Fibrinolysis is pathological when the process becomes excessive or inappropriate. Plasminogen is activated to plasmin which digests fibrin. Both plasmin and fibrin split products inhibit polymerization of fibrin monomers (which is the final step in the coagulation cascade in the formation of a stable clot), resulting in an unstable clot which is rapidly lysed. To our knowledge such a coagulopathy has not been reported to be a complication of pseudoaneurysms.

Simultaneous bilateral carotid endarterectomies.

Twelve patients with bilateral symptomatic lesions of internal carotid arteries have had bilateral carotid endarterectomy at single operations without complications. These were patients up to age 80 who had prior mycardial infarction, stroke with recovery, and hemispheric and nonhemispheric episodes. Neurologist's clearance and three- or four-vessel intracranial-extracranial angiography preceded all operations, which were performed with the patient under general anesthesia. Stump pressure measurements were the principal guideline of adequacy of collateral flow and predictor of safe outcome. The safety of this concept of bilateral operations during one anesthesia can eliminate uncertainties of sequence and timing, obviate delay and indecision, and avoid the hazards of a second anesthetic-operative experience.

Resurrection grasses in India.

A search for desiccation tolerant grasses in India revealed nine grass species (in the genera Eragrostiella, Oropetium and Tripogon) whose ability to recover from airdryness had not previously been reported. Dry leaves of these species recover uninjured within 24 h of plants receiving water. Desiccation tolerance limits were 0%-11% RH (at 28°C). Some species were relatively tall and vigorous and may be useful for grazing purposes in arid areas.

The use of an external dacron shunt in repair of a supraceliac abdominal aorta traumatic aneurysm.

This is the sixth report in the English literature of survival following repair of a supraceliac aortic traumatic aneurysm secondary to penetrating injury. Symptoms, (12 months after a stab wound of the flank), led to discovery of an aneurysm 15 cm in diameter, originating from the left side of the supraceliac aorta. Repair was accomplished with a temporary thoracoabdominal bypass shunt graft of woven Dacron.

Carotid cross-over bypass. Cerebral revascularization after ligation of common carotid artery.

A rationale is presented for extra-anatomic carotid cross-over bypass to maintain or restore blood flow to the internal carotid artery distal to sites of disruption and ligation of a common carotid artery. Anatomic evidence indicates that the attachment of the carotid sheath to the hyoid bone is a barrier to spread of infection cephalad to that level. A patient with infected and disrupted right common carotid artery associated with an esophageal fistula was treated by double ligation of the artery. Contralateral hemiplegia 48 hours later forced consideration of cerebral revascularization. Left carotid angiography demonstrated patent cerebral vessels on the right, with retrograde filling of the right internal carotid artery to the bifurcation. These findings were interpreted as consistent with technical feasibility of external carotid to external carotid cross-over vein bypass in a suprahyoid location, avoiding reconstruction in an infected area and resulting in prompt recovery of function.

Angiographic diagnosis of small intestinal intussusception.

The outstanding angiographic features of small intestinal intussusception are: (a) abrupt disappearance of mesenteric vessels at the neck of the intussusception with crowding of the vasa recta; (b) appearance of long collateral channels at the neck of intussusception; (c) angulation and retraction of major intestinal branches; (d) reversal of the course and angulation of the invaginated mesenteric vessels; (e) overlapping of the mesentery vessels by branches of the intussuscipiens; (f) abrupt change in the appearance of the vasa rectae of the distended intussuscipiens and the distal nondistended small intestines.

Bilateral carotid aneurysms secondary to radiation therapy.

A patient was seen with symptomatic, rapidly expanding aneurysms that developed in both carotid arteries 4 years after bilateral radiation to the neck, left combined mandibular resection, and radical neck dissection. The presenting symptoms were pain and transient ischemic attacks of cerebrovascular insufficiency. The aneurysms were treated uneventfully be resection and vein-graft replacement at 15-day intervals. Microscopy demonstrated typical radiation changes. Effects of radiation on arteries are reviewed.

Civilian arterial injuries.

During 1968-1973, 122 patients with 126 arterial injuries were treated. In 94 instances (90 patients), these injuries involved extremities. Systolic blood pressure was below 90 mm Hg upon admission in 55.6% of all patients and 37.7% of those with injuries to arteries of the extremities. The decision for operative exploration and repair of arteries of extremities was based largely on clinical grounds (shock, loss of pulse). Preoperative arteriography was needed infrequently, while operative angiography was nearly routine. Although several cases of late revascularization or traumatic thrombosis of renal artery have been reported, hypertension complicates the postoperative period, and early, aggressive approach is essential. Mortality was 10.6%, from aortic injuries. There were no deaths among patients with arterial injuries distal to inguinal ligament or thoracic outlet. The amputation rate from reconstruction failure was 1.1%, none occurring in the last 3 years of the series. The high patency rate and lack of evidence of pulmonary embolization suggest that associated venous injuries be repaired routinely. Arterial injuries represent ideal lesions (normal arterial wall with excellent run-in and run-off). Prompt treatment of shock and early, proper management of patients' mechanical disruptions will salvage many lives and most limbs.

Traumatic pseudoaneurysms: a review of 32 cases.

The management of 23 patients with traumatic pseudoaneurysms is presented. A pulsatile mass associated with pain was the usual presentation. Hypertension and hypovolemic shock from rupture are uncommon presentations but potential hazards of this lesion. Twenty-one pseudoaaeurysms were treated surgically. Resection with end-to-end anastomosis (eight patients), with graft replacement (one patient), with lateral repair (seven patients) was done. Hypothermia with circulatory arrest and external Dacron shunt were used to prevent visceral ischemia during high aortic occlusion. There were no mortalities or significant postoperative complications.