Raymond S. Martin

Primary graft infections

An amputation rate of 8% to 52% and a mortality rate of 13% to 58% make vascular prosthetic graft infections the most dreaded complication facing a vascular surgeon. In 1978 a randomized prospective double-blind study reported a statistically significant decrease in wound infections in patients treated with prophylactic antibiotics whereas the graft infection difference only approached statistical significance. The present study reviews 2614 arterial prosthetic grafts implanted from January 1975 through June 1986. Twenty-four patients were identified as having a prosthetic graft infection, yielding an overall infection rate of 0.92%. Staphylococcus aureus was the most common organism, occurring in one third of the cases. The most common graft material was polytetrafluoroethylene (PTFE) (33%) followed by Dacron (29%), composite PTFE and Dacron (20%), and umbilical vein grafts (9%). Diabetes was a common factor in one third of the patients. Symptoms of infection were present in 15 patients (63%) within 3 months of operation, with 11 patients showing symptoms within 30 days. The longest interval between operation and onset of symptoms was 48 months. Prophylactic antibiotics were administered to 22 of the 24 patients, but in only 7 of the 22 (29.5%) were they given according to our usual practice. All patients required removal of the infected prosthesis, with limb loss in 17% and death in 17%.

Renal artery aneurysm: Selective treatment for hypertension and prevention of rupture

Thirty-nine patients with renal artery aneurysm (RAA) were seen over a period of 15 years. Among 20 women and 19 men, 31 were found to have solitary aneurysms, and eight had multiple RAA. Thirty-three patients had diastolic hypertension; nine of them proved to be of renovascular origin. Of the 18 patients who underwent RAA resection, 13 had reconstruction for treatment of hypertension, three had a solitary functional kidney, one had recurrent flank pain, and one had resection for prevention of rupture in a woman of childbearing age. Six of the 18 patients had aneurysmorrhaphy with primary repair or patching, seven had a resection with an aortorenal bypass, and five patients had six ex vivo renal reconstructions with multiple anastomoses. Nephrectomy was performed in two patients with RAA rupture at the time of childbirth and in one patient with hypertension and RAA in a poorly functioning kidney. Reconstructive procedures for documented renovascular hypertension in seven patients resulted in improvement in all cases. Blood pressure improved in only six of 10 patients operated on with hypertension and no lateralization of renovascular studies. Eighteen patients were observed for one to 16 years without surgery, and none experienced rupture. Resection of RAA is indicated to treat patients with renovascular hypertension, patients with hypertension and a solitary functional kidney, and selected patients with severe hypertension and to prevent rupture in women who may become pregnant. Other patients with asymptomatic RAA can be safely observed clinically without serial arteriograms and without fear of rupture.(ABSTRACT TRUNCATED AT 250 WORDS)

Cryopreserved saphenous vein allografts for below-knee lower extremity revascularization.

ObjectiveCryopreserved saphenous vein allografts have been offered as an alternative conduit for bypass in ischemic limbs. The authors examined the efficacy of this conduit for arterial bypass to the distal popliteal and tibial arteries in patients in whom autogenous vein was not available. Summary Background DataPrevious experience with arterial and venous allografts has been unsatisfactory because of aneurysmal degeneration and poor patency. Endothelial loss and host rejection have been suggested as mechanisms of graft failure. Cryopreservation by modern techniques with rate controlled freezing, dimethyl sulfoxide (DMSO), and other cryopreservants, has addressed these issues and rekindled interest in vein allografts. MethodsOver a period of more than 5 years, 115 cryopreserved vein allografts were implanted in 87 limbs to the distal popliteal (14) or tibial (101) arteries. The indication for surgery was rest pain in 56 procedures (49%), gangrene in 36 (31%), claudication in 21 (18%), and replacement of aneurysmal allografts in 2. Follow-up was 1 to 61 months (mean 25 months). ResultsThere was no significant difference in patency related to site of proximal or distal anastomosis, patency of runoff vessels, use of anticoagulation, age, sex, diabetes, hypertension, smoking, indication, source of graft, or use of multiple segments. Revision was required in six grafts for aneurysmal dilatation. Histologic examination of explanted sections of allografts showed no immune response, and immunosuppressive drugs were not used. ConclusionsAlthough limb salvage has been satisfactory, long-term patency rates for cryopreserved vein allografts are poor when compared with autogenous vein. The cost of cryopreserved allografts far exceeds that of prosthetic grafts, for which comparable and superior results have been reported. Use of cryopreserved vein allografts should be reserved for situations in which adequate lengths of autogenous vein do not exist and the risk of infection of prosthetic grafts is high.

The evolving surgical management of recurrent carotid stenosis

The traditional approach to recurrent carotid stenosis has been repeat endarterectomy or patch angioplasty. Concern with the durability of repeat carotid endarterectomy has resulted in our use of carotid resection with autogenous graft interposition. This study was designed to determine the outcome and efficacy of carotid resection compared with repeat carotid endarterectomy in the management of recurrent carotid stenosis. From 1974 to 1991, 162 operations (repeat carotid endarterectomy 105, carotid resection 57) were performed for recurrent carotid stenosis. Indication for operation was hemispheric symptoms in 63% of patients, nonlateralizing symptoms in 25%, asymptomatic stenosis in 7%, and previous stroke in 5%. Ninety-one percent of patients had stenosis greater than 90% on arteriography. The perioperative stroke rate for carotid resection was 3.5%, with a subsequent rate of 0.0064 strokes per year. For repeat carotid endarterectomy, the perioperative stroke rate was 1.9% with a subsequent rate of 0.011 strokes per year. Graft patency after carotid resection was 93% (mean follow-up, 35 months). Four patients treated with carotid resection had graft thrombosis, and two of the four remained asymptomatic. After repeat carotid endarterectomy, one patient had carotid thrombosis, and recurrent stenosis greater than 50% developed in 23 patients (mean follow-up, 64 months). Twenty patients treated with repeat carotid endarterectomy underwent an additional operation for further symptomatic recurrent carotid stenosis. We conclude carotid resection is a safe and effective alternative to repeat carotid endarterectomy for patients undergoing operation for recurrent carotid stenosis.

Technical complications of endovascular abdominal aortic aneurysm repair

PURPOSE Results from 34 endovascular repairs of abdominal aortic aneurysms are reviewed to identify technical complications and relate them to anatomic and technical features of the operation. METHODS Twenty-one patients underwent attempted tube graft repair (mean follow-up, 13 months). Thirteen patients underwent placement of a bifurcated graft (mean follow-up, 7.2 months). RESULTS Twenty-five patients (74%) underwent repair without technical complication (16 tube graft and nine bifurcated graft). Of five patients who had tube graft complications, two involved small iliac arteries and resulted in arterial injury. One of these patients needed a femorofemoral bypass procedure, and the other required conversion to standard operation. Two patients had distal leaks associated with the attachment system, and one patient had misplacement of the distal attachment system. The two patients who had leaks were followed-up; one required operation after 7 months, whereas the other leak sealed. The patient who had distal attachment system misplacement had a second endograft placed within the first to provide a distal seal. The four patients who had bifurcated graft complications involved two graft limb stenoses, one managed with a Palmaz stent and the other with balloon angioplasty. The patient treated with balloon angioplasty had graft thrombosis 1 week after the operation, which resulted in the need for a femorofemoral bypass procedure. Another bifurcated graft patient had a graft limb twist, which has resulted in chronic claudication. One patient had placement of a limb too proximal in the common iliac artery with chronic leak, and an open operation was performed 18 months later. CONCLUSIONS Technical complications in this series seem to be associated with short distal necks, small iliac arteries, tortuous iliac arteries, and atherosclerosis at the aortic bifurcation. We believe that experience and understanding of these issues will reduce the risk of these complications in the future.

Case management in cerebral revascularization

PURPOSE We examined the clinical and financial outcomes of case management coupled with the initiation of selective use of the intensive care unit (ICU) in all cerebral revascularization procedures. METHODS Three hundred eighty-four procedures in 331 patients were retrospectively reviewed. Morbidity and mortality rates, hospital length of stay, cost, and ICU or hospital readmissions were examined. Hypertension was examined as an independent variable for its effect on patient outcome. RESULTS Cerebral revascularization, including carotid endarterectomy, vertebral-carotid artery transposition, and subclavian-carotid artery transposition, yielded a 0.78% stroke rate and 0.26% perioperative death rate in this series. ICU admission was necessary in nine patients (2.3%) for cardiac or respiratory instability. Three patients (0.78%) required transfer to the ICU for management of hypertension or hypotension. The mean hospital length of stay after institution of case management was reduced by 2.1 days, and the mean cost was decreased by

Surgical treatment of common carotid artery occlusion

1987, a savings of 28.9% of total hospital cost. CONCLUSION The dual approach of case management and selective use of the ICU promotes quality patient care, conserves financial resources without adversely affecting morbidity or mortality rates, enhances physician/nurse collaboration, and improves patient satisfaction.

Cefamandole versus cefazolin in vascular surgical wound infection prophylaxis: Cost-effectiveness and risk factors *

Eight patients with common carotid artery (CCA) occlusion underwent bypass with saphenous vein to either the carotid bifurcation (five), the internal carotid artery (two), or the external carotid artery (one). Indications included ipsilateral transient ischemic attack (two), recent nondisabling hemispheric stroke (two), and transient nonhemispheric cerebral symptoms (two). Two asymptomatic patients with CCA occlusion and contralateral internal carotid stenosis underwent prophylactic revascularization prior to planned aortic surgery. There were no perioperative strokes, occlusions, or deaths. Late ipsilateral stroke occurred in two patients, and one patient had a single transient ischemic attack after 2 years. The four patients with preoperative transient cerebral ischemia experienced relief of their symptoms. Duplex ultrasound is an accurate screening modality for distal patency. Collateral filling of the internal or external carotid artery can usually be demonstrated after aortic arch or retrograde brachial contrast injection. End-to-end distal anastomosis after endarterectomy eliminates the original occlusive plaque as a potential source of emboli. The subclavian artery is preferred for inflow on the left. The CCA origin is easily accessible for inflow on the right. Bypass of the occluded CCA is safe and may be effective in relieving transient cerebral ischemic symptoms, although long-term ipsilateral neurologic sequelae may still occur.

Recurrent carotid artery stenosis: resection with autogenous vein replacement

PURPOSE Recent studies of perioperative antimicrobial prophylaxis have indicated an improved efficacy of beta-lactamase-stable cephalosporins compared with cefazolin, the most commonly used prophylactic agent. Previous studies in our institution have revealed a superiority of cefamandole to cefazolin in patients undergoing heart surgery, although there was no difference between cefazolin and cefuroxime in patients undergoing peripheral vascular surgery. This study was therefore designed to compare cefamandole with cefazolin in wound infection prophylaxis in clean vascular surgery. METHODS The study was conducted from August 1990 through May 1992 and consisted of 893 patients with aortic or infrainguinal arterial procedures randomized to receive either cefamandole or cefazolin. RESULTS The difference in infection rates associated with cefamandole versus cefazolin prophylaxis (3.2% vs 1.9%, respectively) was not significant (p = 0.42). A cost savings of approximately

Cefuroxime versus cefazolin as prophylaxis in vascular surgery

95,000 per year at our institution favors the continued use of cefazolin over cefamandole. Risk factor analysis was carried out for preoperative and postoperative events that might have predisposed to infection. Only preoperative use of aspirin and the postoperative finding of a lymphocele correlated with a higher infection rate. CONCLUSIONS Cefazolin continues to be the most cost-effective antibiotic for prophylaxis in clean vascular surgical procedures.