R.C. Darling

Advances in the surgical repair of ruptured abdominal aortic aneurysms

Over the past two decades, the mortality rate for elective repair of infrarenal abdominal aortic aneurysms has improved to an acceptable level (< 5%). However, surgical results of ruptured abdominal aortic aneurysms have remained fairly constant with about 50% in hospital mortality rates. Growing experience with the use of the left retroperitoneal exposure for elective aortic surgery allowed the authors to extend the use of this technique to the repair of ruptured abdominal aortic aneurysm. The extended left retroperitoneal approach using a posterolateral exposure through the 10th intercostal space allowed the surgeon expeditiously and reliably to obtain supraceliac aortic control by dividing the left crus of the diaphragm in all patients. In total, 104 aortic replacements were performed for ruptured abdominal aortic aneurysm during the past 7 years. Of these patients, 87 were men and 17 women; mean(range) age was 72(52-95) years. Hemodynamic instability (as defined by a systolic blood pressure of < 90 mmHg) was present before surgery in 41% (43/104) of patients. The operative mortality rate was 27.9% (29/104). Preoperative hemodynamic instability, time of operative delay and aortic cross-clamp time did not correlate with operative mortality. The median duration of intensive care unit stay was 4 (range 1-60) days and hospital stay 11 (range 6-175) days. The results of this series identified that a change in the operative technique for the repair of ruptured abdominal aortic aneurysm beneficially affected patient survival. The authors suggest that expeditious supraceliac control without thoracotomy is an excellent alternative and offers an advantage in the surgical management of ruptured abdominal aortic aneurysm.

Expeditious management of ischemic invasive foot infections.

Management of infected ischemic diabetic limbs requires antibiotic therapy, abscess drainage, and revascularization. However, revascularization is often delayed for several days or weeks as the infection is controlled. In an effort to decrease hospital stay and costs and to increase limb salvage, a series of 974 extremities with distal occlusive disease were managed with autogenous distal bypass. Some 136 of these limbs (125 diabetic) had severe invasive infections. These patients received intravenous antibiotics in all cases and abscess drainage if necessary. Vascular reconstruction was carried out as soon as possible, within 48 h of admission. An in situ bypass was used preferentially (107 cases). Patients were maintained on intravenous antibiotics in the perioperative period. Partial foot amputations, when necessary, were performed in 111 cases, usually 3-5 days after vascular reconstruction. There were no graft infections or major wound infections. There were two cases of skin edge necrosis requiring reoperation due to flap mobilization and consequent ischemia. Urgent revascularization with an autogenous conduit may be carried out in patients with invasive foot infections expeditiously, with high rates of limb salvage. Graft and wound infections are not common in this setting. Costly prolonged pre-bypass hospitalization in these cases is unnecessary.

Bilateral carotid endarterectomy during the same hospital admission

The efficacy of carotid endarterectomy for the prevention of strokes has been well demonstrated in recent multicenter randomized trials. However, patients presenting with bilateral significant disease pose a difficult problem to the vascular surgeon. Currently, bilateral carotid endarterectomies are staged at varying intervals between operations, with surgeon and patient weighing the risks of waiting for surgery versus the risks of having both procedures done within a shortened interval. There are few data and no consensus on the optimal time interval between these operations. In order to evaluate the timing of carotid endarterectomies in patients with severe bilateral disease, the authors reviewed their experience with patients who had bilateral procedures performed during one hospitalization. Over the past 5 years, they have performed 204 such carotid endarterectomies in 102 patients. Cervical block anesthesia was used in 99% (201/204) of these procedures. All patients either had symptomatic disease, > 60% stenosis or severe ulcerative plaque as defined by duplex scan and/or preoperative angiography. Symptomatic stenoses were the operative indications in 39% (80/204) of the patients; the remaining 61% (124/204) were symptom-free. The majority of patients (80%; 164/204) had their second procedure performed within 2 days of their first operation. There was no operative mortality and only one permanent neurologic defect in this group for a combined stroke mortality rate of 1%. Three patients (1.5%) had transient neurologic deficits postoperatively which completely resolved by discharge. These data show that bilateral carotid endarterectomies can be performed safely and effectively during one hospital admission with a short interprocedural interval and without an increase in mortality or morbidity.

A critical approach for longitudinal clinical trial of stretch PTFE aortic grafts.

Adaptation of new clinical products should be based upon thorough scientific evaluation of properties and performance in vitro and in vivo. Developmental animal research experimentation is classically carried out by the manufacturer with eventual government approval. However, objective data needs to be recorded during clinical trials including handling characteristics, bleeding, tensile strength, kinking, seamline break, dilatation, anastomotic deterioration, patency, and incorporation. Since April 1991, 1010 stretch polytetrafluoroethylene (PTFE) aortic grafts have been implanted at our institution and data were recorded prospectively. Six hundred and seven were for elective abdominal aortic aneurysms, 46 for symptomatic abdominal aortic aneurysms, 58 for ruptured abdominal aortic aneurysms, 17 for elective thoracoabdominal aneurysms, 3 for ruptured thoracoabdominal aneurysms and the remainder were for various aortoiliac pathology. Average age of the patients was 69 (range: 10-95), 66% were males, 25% were diabetics. Overall operative mortality was 5.8% (2.9% in elective cases and 26.6% in emergent cases). There were 23 occlusions; 21 were revised and 2 were replaced with axillofemoral bypasses. Estimated blood loss was 784 cc in elective cases and 1918 cc in emergent cases. Grafts were followed by duplex ultrasound or CT scan every 3 months during the first year and every 6 months thereafter. There were no graft dilatations or false aneurysms in this series. There was one graft infection and no perigraft seromas or anastomotic deteriorations during this follow up. Follow up was complete in 94% of these patients. In conclusion, stretch PTFE graft has acceptable handling characteristics, no excessive bleeding at the suture line and had no anastomotic or graft dilatation. This graft material was suitable for thoracic, visceral, renal and abdominal aortic reconstructions.

Access to the right renal artery from the left retroperitoneal approach

One of the perceived limitations of the left retroperitoneal approach to the aorta is inadequate access to the right renal artery. Many consider the need for a concomitant right renal artery revascularization a contraindication to performing an aortic reconstruction through the left retroperitoneum. Exposure of the right renal artery can be difficult due to the posterior course of the artery behind the vena cava. However, when the aorta is transected, the right renal artery can be easily approached with anterior and cephalad displacement of the aortic root. Over the past 3 years, 52 patients have had right or bilateral renal artery revascularization via the left retroperitoneal approach; of these procedures, 37 were performed with concomitant aortic procedures. In total, 34 patients had bilateral and 18 had unilateral revascularizations. Five patients had a transaortic endarterectomy performed, and 36 were bypassed with 6-mm expanded polytetrafluoroethylene side limbs from the aortic graft. Indications for revascularization were: 39 for suprarenal aortic bypass, seven for renal salvage and six for primary renovascular hypertension. All reconstructions have remained patent and all have been followed by serial duplex and renal flow scans (follow-up for 1-42 months). The operative mortality rate was 5.8% (3/52). There were no major cardiorespiratory complications in this group. Adequate exposure to the proximal right renal artery can be obtained through the left retroperitoneal approach to the aorta, and successful revascularization of one of both renal arteries can be technically performed with acceptable mortality and morbidity.

Arterial reconstruction for limb salvage: is the terminal peroneal artery a disadvantaged outflow tract

BACKGROUND Arterial reconstructions performed for limb salvage have increasingly used distal perimalleolar and pedal arteries as outflow tracts. However, a paucity of reports comparing the patency and limb salvage rates of these outflow tracts has been published. In this report we examine our experience with distal peroneal artery reconstructions for limb salvage. METHODS During the past 14 years 159 bypasses were performed to the distal peroneal artery (within 5 cm of the malleolus), 157 of which were performed by the medial approach and two by the lateral approach. RESULTS Sixty-three percent of the patients were male, 65% were diabetics, and 43% were smokers; the average age was 72.6 years. Sixty-five percent of the bypasses were performed with the in situ technique. Thirty-one percent of the bypasses were performed with translocated or spliced vein technique, and seven (4%) were performed with prosthetic technique. Secondary patency rates for distal peroneal artery bypass grafts at 1 and 5 years were 86% and 75%. The limb salvage rate for distal peroneal artery bypasses was 87% at 5 years. Four hemodynamic failures occurred in this group. Wound complications requiring revision were seen in one patient with a distal peroneal bypass (0.6%). These results do not differ from our results with other perimalleolar vessels. CONCLUSIONS Arterial reconstruction to the distal peroneal artery has acceptable patency and limb salvage rates. These bypasses are as effective and durable as other perimalleolar bypasses.