Lower Extremity Ischemia After Femoral Arteriovenous Bovine Shunts HENRY J. FEE, JR., M.D., ARTHUR L. GOLDING, M.D.
Use of bovine carotid artery grafts for femoral arteriovenous From the Department of Surgery, fistulas is now an accepted method of circulatory access for paUCLA School of Medicine, tients who require chronic hemodialysis. A serious but infreLos Angeles, California 90024 quently mentioned complication of this technique is lower extremity ischemia secondary to an arterial steal phenomenon. Three cases of this syndrome are presented and specific recom- Haimov et al.2 reported on upper extremity ischemia mendations made for preoperative and intraoperative evalua- after arteriovenous fistula and bovine grafts; however, tion in order to avoid this complication. A possible surgical Zincke et al.6 reported the only case of lower extremity technique for correction of this syndrome is also discussed.
TrHE INCREASED survival rate of patients on long-term renal dialysis and the acceptance of patients with multiple systemic diseases have led to serious problems with vascular access. Currently, the external shunt and arteriovenous fistula are the primary methods of access. When these techniques are unsuccessful, many surgeons turn to bovine carotid artery shunts. Rosenberg et al.4 were the first to report their experience with enzymatically treated bovine carotid arteries in dogs. Subsequently, these investigators reported their first experience with the use of the graft in man.5 Although these grafts were used originally as arterial prostheses for reconstruction of limbs with arterial insufficiency, their rise as sites for vascular access for chronic hemodialysis patients has only recently been appreciated. Several recent reports in the literature attest to their efficacy. However, as experience with these grafts increases, serious complications are being reported. Merickel et al.3 reported on 100 patients with bovine shunts in the upper extremity for vascular access, the largest series in the literature. Their complications included infection, hematomas, false aneurysms, edema, pseudodiaphragms, and pseudointernal formation with dissection. Another important complication not noted in their study is arterial steal syndrome. Bussell et al.' and Submitted for publication July 7. 1975.
42
arterial steal syndrome secondary to a bovine graft. The three case reports presented herein and the discussion of this potentially serious complication emphasize methods of surgical correction and prophylactic measures to be taken at the time of the initial operation.
Methods and Materials The bovine grafts had been implanted for purposes of hemodialysis. Graft size varied from 7 to 8 mm in diameter and from 37 to 40 cm in length. They had been anastomosed to the common femoral artery and common femoral vein in an end-to-side fashion. (The length of the anastomosis varied from 1.5 to 2.0 cm depending on the size of the recipient vessel.) The bovine graft formed a loop in a superficial subcutaneous tunnel on the anterior
thigh. The records of 170 patients who received femoral arteriovenous bovine shunts (FAVBS) were reviewed for evidence of arterial insufficiency to the lower extremity. Three patients with the symptomatology and physical findings of severe arterial steal syndrome were identified. Case Reports Case 1. A 64-year-old non-diabetic woman with chronic renal failure and chronic hemodialysis secondary to nephrosclerosis since 1970 and congestive heart failure since 1968 was admitted for a vascular access procedure. On physical examination, she was noted to have good peripheral pulses of the upper and lower extremities.
V.ol.
183
.
No.
ISCHEMIA AFTER BOVINE SHUNTS
43
She had had several arteriovenous fistulas and arteriovenous shunts of the upper extremity. Because of decreasing flow in her brachial artery to brachial vein saphenous graft, a left FAVBS* was inserted, forming a loop on the anterior thigh. Postoperatively, the shunt was noted to be working well. However, within a few hours the patient started to complain of severe pain and swelling of her lower extremity; the distal pulses to that extremity were noted to be absent. On the first postoperative day, an angiogram showed that the shunt and femoral artery were patent. The shunt was removed and the artery reconstructed. However, pain and swelling of the lower extremity persisted and pulses did not return. Symptoms were attributed to severe swelling secondary to the ischemia. Foot drop had also developed. Anterior and posterior compartment fasciotomies were performed. Postoperatively, distal pulses returned. and swelling gradually subsided. Six months after operation she was noted to have good pulses and viable skin, but a partial motor and sensory loss was present.
Comment: Although several segments of femoral artery narrowing were demonstrated on arteriogram, the patient was asymptomatic and had distal pulses preoperatively. Thus, she had probably not developed collaterals to her lower extremity, and the stenotic areas in her femoral system became critical stenoses when the perfusion pressure was lowered by creation of the arteriovenous shunt. The ischemia produced by the "steal" threatened the viability of the extremity, and although corrective measures were taken, permanent disability resulted. Case 2. A 49-year-old non-diabetic woman with chronic renal failure secondary to chronic pyelonephritis had required chronic hemodialysis for three years prior to admission. On physical examination, she had good pulses of the lower extremity and evidence of a clotted bovine shunt of her left arm. A left FAVBS was inserted. Postoperatively, pulses to the distal left extremity were absent. However, when the graft was occluded, these pulses returned. Over the ensuing few days, decreased sensation and occasional numbness of the left leg developed. Two weeks postoperatively, an ischemic ulcer over the head of the left first metatarsal was noted, and there was drainage from the left groin incision. However, an angiogram showed no evidence of a false aneurysm and demonstrated that bovine shunt and femoral artery were patent (Fig. 1). Ten weeks postoperatively, a false aneurysm of the bovine shunt ruptured and the shunt was excised and the femoral artery reconstructed. Pulses to the left lower extremity returned, and the patient's symptoms of ischemia disappeared. A right FAVBS was subsequently inserted without loss of the distal pulses and without development of symptoms of ischemia.
FIG. 1. Arteriogram (Patient 2) demonstraiting superficial femoral artery.
patent
graft and
Case 3. A 33-year-old juvenile diabetic hypertensive woman with chronic renal failure and chronic hemodialysis secondary to the diabetes was admitted for placement of an FAVBS. She gave no history of claudication and had good distal pulses in both lower extremities. She underwent a left FAVBS without incident. However, on the ninth postoperative day, she noted intermittent claudication of the left calf and was found to have absent left distail pulses. An arteriogram revealed partial arteriosclerotic occlusion of the left superficial femoral artery (Fig. 2) without evidence of thrombosis or embolism. Doppler pressure measurements showed substantially lower pressures in the left leg that returned to normal on manual occlusion of the bovine shunt (Table 1). The groin incision opened. and flow in the bovine shunt was measured at 2800 cc/min. This reduced to 200 cc/min with a dacron band. Postoperatively, she was asymptomatic; her left distal pulses were palpable. and her left Doppler pressures returned to normal. Unfortunately. the bovine shunt subsequently thrombosed.
Comment: Although the patient had good peripheral pulses preoperatively, after placement of the left FAVBS, ischemic symptoms developed, and her distal pulses were not palpable. When the shunt was removed, the pain disappeared and the pulses returned. It is interesting that she was able to tolerate a right FAVBS without ischemic signs or symptoms. This implies that a localized iliofemoral occlusion rather than myocardial or generalized aortic disease may determine the extremity which is at Comment: This patient illustrates the difficulty with risk. banding the bovine shunt in the steal syndrome. Had the flow not been decreased so markedly, perhaps the Femoral arterial venous bovine shunt. thrombosis would not have occurred. However, turwas
was
*
FEE AND GOLDING
44
Ann.
Surg. * January 1976
TABLE 1. Doppler Pressures on Patient 3
R Side
Wrist Thigh Calf Ankle
FIG. 2. Arteriogram (Patient 3) demonstrating the critical stenosis in the superficial femoral artery.
bulence caused by the band even when flow is adequate.
may
be the etiologic factor
Discussion Arterial insufficiency of the lower extremity secondary to a FAVBS is a serious problem. Most patients on chronic renal dialysis have severe atherosclerosis and, thus, are susceptible to this complication. Many of these patients have signs of claudication preoperatively and obviously are poor candidates for a femoral shunt. However, many patients are asymptomatic with moderate to severe occlusive disease of the femoral arteries. These
140 mm 190 mm 140 mm 130 mm
Hg Hg
Hg Hg
L Side Graft Open 140 110 80 60
mm Hg mm Hg mm Hg
mm Hg
L Side Graft Occluded
140 180 150 120
mm Hg mm Hg mm Hg mm Hg
L Side Graft Banded
164 180 156 140
mm Hg mm Hg mm Hg mm Hg
patients are at risk when the perfusion pressure is lowered by shunting of flow through the femoral vein. This lowered perfusion pressure allows the stenotic area to become a critical stenosis, and flow to the leg is diminished substantially. Arteriograms for Patients 1 and 3 showed no stenosis at the suture line, and contrast medium was visualized in the graft and the femoral artery distal to the anastomosis (Fig. 2). However, there was plaque in the distal superficial femoral artery. The shunt can markedly decrease the pressure in the distal arterial system, as all three patients lost their distal pulses after operation, and these returned when the grafts were removed. Doppler findings in Patient 3 documented the markedly decreased pressure in the left lower extremity as compared to the right; with the shunt occluded, they returned to normal. In Patient 3, the intraoperative flow of 2800 cc/min through the shunt indicates a large left-to-right shunt. The significance of this shunt can be appreciated when one notes that with banding to decrease the flow to 200 cc/min, the Doppler measurement of the left lower extremity returned to normal, and the patient became asymptomatic. To avoid arterial insufficiency of the lower extremity secondary to FAVBS, certain screening procedures should be used. The patient should be carefully interviewed for any symptom of rest pain or claudication, and a walking tolerance test should be performed. Doppler pressures of the lower extremities will help to delineate any occult lesion that may be present. Roentgenograms of the extremity should be obtained to screen for calcification of the distal arteries, indicating severe disease. Finally, nerve conduction studies should be obtained to define baseline deficits secondary to uremia or diabetes. If the above examinations do not identify the patient as a significant risk and a FAVBS is performed, intraoperative flows and Doppler pressures should be obtained. These flows can then be adjusted to satisfactory levels with banding of the shunt or use of a graft smaller in diameter. Flows of 500 cc/min are adequate for dialysis and should maintain graft patency. If the patient becomes symptomatic postoperatively, the walking tolerance test, Doppler pressures, and nerve conduction studies should be repeated. The majority of renal dialysis patients will
Vol. 183 * No.
ISCHEMIA AFTER BOVINE SHUNTS
tolerate a bovine carotid artery shunt without evidence of arterial insufficiency. The incidence in our series of FAVBS was low. With proper screening and intraoperative precautions, it may be possible to eliminate this complication entirely.
4.
References
5.
1. Bussell. J. A.. Abbott. J. A. aind Lim. R. C.: A Radial Steal Syndrome with Arteriovenous Fistula for- Hemodialysis. Ann. Intern. Med.. 75:387. 1971. 2. Haimov. M.. Burrows. L.. Baiez. A.. et al.: Alternatives forVascular Access for Hemodialysis: Experience with Auto-
3.
6.
45
genous Saphenous Vein Autogr-.afts and Bovine Heterogr-afts. Surgery. 75:447. 1974. Merickel. J. H.. Anderson. R. C.. Knutson. R.. et al.: Bovine Carotid Arter-y Shunts in Vasculair Access Surgery. Arch. Surg.. 109:245. 1974. Rosenberg. N.. Gaughran. E. R. L.. Hunder-son. J.. et al.: The Use of Arterial Implants Prepar-ed by Enzymatic Modification of Heterologous Blood Vessels. Surg. Forum. 6:242. 1956. Rosenberg. N.. Hunderson. J.. Lord. G. and Bothwell. J. W.: An Arterial Prosthesis of Heterologous Origin. JAMA 187: 741. 1964. Zincke. H.. Hirsche. B. L.. Amamoo. D. G.. et al.: The Use of Bovine Carotid Grafts for Hemodialysis and Hyperalimentation. Surg. Gynecol. Obstet.. 139:350. 1974.
Use of bovine carotid artery grafts for femoral arteriovenous From the Department of Surgery, fistulas is now an accepted method of circulatory access for paUCLA School of Medicine, tients who require chronic hemodialysis. A serious but infreLos Angeles, California 90024 quently mentioned complication of this technique is lower extremity ischemia secondary to an arterial steal phenomenon. Three cases of this syndrome are presented and specific recom- Haimov et al.2 reported on upper extremity ischemia mendations made for preoperative and intraoperative evalua- after arteriovenous fistula and bovine grafts; however, tion in order to avoid this complication. A possible surgical Zincke et al.6 reported the only case of lower extremity technique for correction of this syndrome is also discussed.
TrHE INCREASED survival rate of patients on long-term renal dialysis and the acceptance of patients with multiple systemic diseases have led to serious problems with vascular access. Currently, the external shunt and arteriovenous fistula are the primary methods of access. When these techniques are unsuccessful, many surgeons turn to bovine carotid artery shunts. Rosenberg et al.4 were the first to report their experience with enzymatically treated bovine carotid arteries in dogs. Subsequently, these investigators reported their first experience with the use of the graft in man.5 Although these grafts were used originally as arterial prostheses for reconstruction of limbs with arterial insufficiency, their rise as sites for vascular access for chronic hemodialysis patients has only recently been appreciated. Several recent reports in the literature attest to their efficacy. However, as experience with these grafts increases, serious complications are being reported. Merickel et al.3 reported on 100 patients with bovine shunts in the upper extremity for vascular access, the largest series in the literature. Their complications included infection, hematomas, false aneurysms, edema, pseudodiaphragms, and pseudointernal formation with dissection. Another important complication not noted in their study is arterial steal syndrome. Bussell et al.' and Submitted for publication July 7. 1975.
42
arterial steal syndrome secondary to a bovine graft. The three case reports presented herein and the discussion of this potentially serious complication emphasize methods of surgical correction and prophylactic measures to be taken at the time of the initial operation.
Methods and Materials The bovine grafts had been implanted for purposes of hemodialysis. Graft size varied from 7 to 8 mm in diameter and from 37 to 40 cm in length. They had been anastomosed to the common femoral artery and common femoral vein in an end-to-side fashion. (The length of the anastomosis varied from 1.5 to 2.0 cm depending on the size of the recipient vessel.) The bovine graft formed a loop in a superficial subcutaneous tunnel on the anterior
thigh. The records of 170 patients who received femoral arteriovenous bovine shunts (FAVBS) were reviewed for evidence of arterial insufficiency to the lower extremity. Three patients with the symptomatology and physical findings of severe arterial steal syndrome were identified. Case Reports Case 1. A 64-year-old non-diabetic woman with chronic renal failure and chronic hemodialysis secondary to nephrosclerosis since 1970 and congestive heart failure since 1968 was admitted for a vascular access procedure. On physical examination, she was noted to have good peripheral pulses of the upper and lower extremities.
V.ol.
183
.
No.
ISCHEMIA AFTER BOVINE SHUNTS
43
She had had several arteriovenous fistulas and arteriovenous shunts of the upper extremity. Because of decreasing flow in her brachial artery to brachial vein saphenous graft, a left FAVBS* was inserted, forming a loop on the anterior thigh. Postoperatively, the shunt was noted to be working well. However, within a few hours the patient started to complain of severe pain and swelling of her lower extremity; the distal pulses to that extremity were noted to be absent. On the first postoperative day, an angiogram showed that the shunt and femoral artery were patent. The shunt was removed and the artery reconstructed. However, pain and swelling of the lower extremity persisted and pulses did not return. Symptoms were attributed to severe swelling secondary to the ischemia. Foot drop had also developed. Anterior and posterior compartment fasciotomies were performed. Postoperatively, distal pulses returned. and swelling gradually subsided. Six months after operation she was noted to have good pulses and viable skin, but a partial motor and sensory loss was present.
Comment: Although several segments of femoral artery narrowing were demonstrated on arteriogram, the patient was asymptomatic and had distal pulses preoperatively. Thus, she had probably not developed collaterals to her lower extremity, and the stenotic areas in her femoral system became critical stenoses when the perfusion pressure was lowered by creation of the arteriovenous shunt. The ischemia produced by the "steal" threatened the viability of the extremity, and although corrective measures were taken, permanent disability resulted. Case 2. A 49-year-old non-diabetic woman with chronic renal failure secondary to chronic pyelonephritis had required chronic hemodialysis for three years prior to admission. On physical examination, she had good pulses of the lower extremity and evidence of a clotted bovine shunt of her left arm. A left FAVBS was inserted. Postoperatively, pulses to the distal left extremity were absent. However, when the graft was occluded, these pulses returned. Over the ensuing few days, decreased sensation and occasional numbness of the left leg developed. Two weeks postoperatively, an ischemic ulcer over the head of the left first metatarsal was noted, and there was drainage from the left groin incision. However, an angiogram showed no evidence of a false aneurysm and demonstrated that bovine shunt and femoral artery were patent (Fig. 1). Ten weeks postoperatively, a false aneurysm of the bovine shunt ruptured and the shunt was excised and the femoral artery reconstructed. Pulses to the left lower extremity returned, and the patient's symptoms of ischemia disappeared. A right FAVBS was subsequently inserted without loss of the distal pulses and without development of symptoms of ischemia.
FIG. 1. Arteriogram (Patient 2) demonstraiting superficial femoral artery.
patent
graft and
Case 3. A 33-year-old juvenile diabetic hypertensive woman with chronic renal failure and chronic hemodialysis secondary to the diabetes was admitted for placement of an FAVBS. She gave no history of claudication and had good distal pulses in both lower extremities. She underwent a left FAVBS without incident. However, on the ninth postoperative day, she noted intermittent claudication of the left calf and was found to have absent left distail pulses. An arteriogram revealed partial arteriosclerotic occlusion of the left superficial femoral artery (Fig. 2) without evidence of thrombosis or embolism. Doppler pressure measurements showed substantially lower pressures in the left leg that returned to normal on manual occlusion of the bovine shunt (Table 1). The groin incision opened. and flow in the bovine shunt was measured at 2800 cc/min. This reduced to 200 cc/min with a dacron band. Postoperatively, she was asymptomatic; her left distal pulses were palpable. and her left Doppler pressures returned to normal. Unfortunately. the bovine shunt subsequently thrombosed.
Comment: Although the patient had good peripheral pulses preoperatively, after placement of the left FAVBS, ischemic symptoms developed, and her distal pulses were not palpable. When the shunt was removed, the pain disappeared and the pulses returned. It is interesting that she was able to tolerate a right FAVBS without ischemic signs or symptoms. This implies that a localized iliofemoral occlusion rather than myocardial or generalized aortic disease may determine the extremity which is at Comment: This patient illustrates the difficulty with risk. banding the bovine shunt in the steal syndrome. Had the flow not been decreased so markedly, perhaps the Femoral arterial venous bovine shunt. thrombosis would not have occurred. However, turwas
was
*
FEE AND GOLDING
44
Ann.
Surg. * January 1976
TABLE 1. Doppler Pressures on Patient 3
R Side
Wrist Thigh Calf Ankle
FIG. 2. Arteriogram (Patient 3) demonstrating the critical stenosis in the superficial femoral artery.
bulence caused by the band even when flow is adequate.
may
be the etiologic factor
Discussion Arterial insufficiency of the lower extremity secondary to a FAVBS is a serious problem. Most patients on chronic renal dialysis have severe atherosclerosis and, thus, are susceptible to this complication. Many of these patients have signs of claudication preoperatively and obviously are poor candidates for a femoral shunt. However, many patients are asymptomatic with moderate to severe occlusive disease of the femoral arteries. These
140 mm 190 mm 140 mm 130 mm
Hg Hg
Hg Hg
L Side Graft Open 140 110 80 60
mm Hg mm Hg mm Hg
mm Hg
L Side Graft Occluded
140 180 150 120
mm Hg mm Hg mm Hg mm Hg
L Side Graft Banded
164 180 156 140
mm Hg mm Hg mm Hg mm Hg
patients are at risk when the perfusion pressure is lowered by shunting of flow through the femoral vein. This lowered perfusion pressure allows the stenotic area to become a critical stenosis, and flow to the leg is diminished substantially. Arteriograms for Patients 1 and 3 showed no stenosis at the suture line, and contrast medium was visualized in the graft and the femoral artery distal to the anastomosis (Fig. 2). However, there was plaque in the distal superficial femoral artery. The shunt can markedly decrease the pressure in the distal arterial system, as all three patients lost their distal pulses after operation, and these returned when the grafts were removed. Doppler findings in Patient 3 documented the markedly decreased pressure in the left lower extremity as compared to the right; with the shunt occluded, they returned to normal. In Patient 3, the intraoperative flow of 2800 cc/min through the shunt indicates a large left-to-right shunt. The significance of this shunt can be appreciated when one notes that with banding to decrease the flow to 200 cc/min, the Doppler measurement of the left lower extremity returned to normal, and the patient became asymptomatic. To avoid arterial insufficiency of the lower extremity secondary to FAVBS, certain screening procedures should be used. The patient should be carefully interviewed for any symptom of rest pain or claudication, and a walking tolerance test should be performed. Doppler pressures of the lower extremities will help to delineate any occult lesion that may be present. Roentgenograms of the extremity should be obtained to screen for calcification of the distal arteries, indicating severe disease. Finally, nerve conduction studies should be obtained to define baseline deficits secondary to uremia or diabetes. If the above examinations do not identify the patient as a significant risk and a FAVBS is performed, intraoperative flows and Doppler pressures should be obtained. These flows can then be adjusted to satisfactory levels with banding of the shunt or use of a graft smaller in diameter. Flows of 500 cc/min are adequate for dialysis and should maintain graft patency. If the patient becomes symptomatic postoperatively, the walking tolerance test, Doppler pressures, and nerve conduction studies should be repeated. The majority of renal dialysis patients will
Vol. 183 * No.
ISCHEMIA AFTER BOVINE SHUNTS
tolerate a bovine carotid artery shunt without evidence of arterial insufficiency. The incidence in our series of FAVBS was low. With proper screening and intraoperative precautions, it may be possible to eliminate this complication entirely.
4.
References
5.
1. Bussell. J. A.. Abbott. J. A. aind Lim. R. C.: A Radial Steal Syndrome with Arteriovenous Fistula for- Hemodialysis. Ann. Intern. Med.. 75:387. 1971. 2. Haimov. M.. Burrows. L.. Baiez. A.. et al.: Alternatives forVascular Access for Hemodialysis: Experience with Auto-
3.
6.
45
genous Saphenous Vein Autogr-.afts and Bovine Heterogr-afts. Surgery. 75:447. 1974. Merickel. J. H.. Anderson. R. C.. Knutson. R.. et al.: Bovine Carotid Arter-y Shunts in Vasculair Access Surgery. Arch. Surg.. 109:245. 1974. Rosenberg. N.. Gaughran. E. R. L.. Hunder-son. J.. et al.: The Use of Arterial Implants Prepar-ed by Enzymatic Modification of Heterologous Blood Vessels. Surg. Forum. 6:242. 1956. Rosenberg. N.. Hunderson. J.. Lord. G. and Bothwell. J. W.: An Arterial Prosthesis of Heterologous Origin. JAMA 187: 741. 1964. Zincke. H.. Hirsche. B. L.. Amamoo. D. G.. et al.: The Use of Bovine Carotid Grafts for Hemodialysis and Hyperalimentation. Surg. Gynecol. Obstet.. 139:350. 1974.
