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In this 6-year study of 101 limbs requiring surgical intervention for upper-extremity vascular trauma, most patients were male, young, and injured by penetrating objects. Injured vessels included 13 axillary/subclavian, 23 brachial, 40 radial, and 25 ulnar arteries. Concomitant injuries included nerve injury in 50 cases, tendon laceration in 29, and bony fracture in 11. Arterial repair was accomplished by primary repair in 54 limbs, vein graft in 26 limbs, and vein patch in 3 limbs. Seventeen arterial injuries were ligated. Ancillary procedures included 30 nerve or 27 tendon repairs. The limb salvage rate was 99%. No functional deficits were noted in those cases with only a vascular injury. In 64% and 25% of patients with nerve or musculoskeletal injury, respectively, the arm was functionally impaired. Prompt diagnosis and surgical intervention eliminate vascular injury as a factor in upper-extremity limb loss or disability. Functional deficits are the result of nerve or orthopedic injuries.

Intravascular stent placement may be an effective treatment for percutaneous transluminal angioplasty (PTA)-induced dissection. Among the first 228 patients treated with Palmaz balloon-expandable intraluminal stents (BEISs) for iliac artery stenosis, stents were used to treat PTA-induced dissection in at least 12 iliac arteries in 11 patients. All 12 vessels were shown by angiography to be severely dissected. Stents were placed at the time of PTA in six vessels and as a separate procedure in the other six. An average of three stents per vessel were employed. All arteries showed marked improvement at angiography. Angiographic follow-up was obtained for eight vessels in seven patients at a mean follow-up time of 12.9 months. All had patent stent lumens with neointima formation, although one stented lumen had narrowed, and another clinical failure occurred despite a patent stented vessel and an ankle-arm index (AAI) of 1.35. With a mean clinical follow-up of 9.5 months, the mean AAI for the stented extremities in the nine remaining patients is 0.91 +/- 0.15. Palmaz BEISs are effective in the management of PTA-induced human iliac artery dissection.

The milliwatt CO2 laser was used to perform end-to-end anastomoses in canine jugular veins. There was a high disruption rate (50%) in laser-welded veins (n = 10). Fibrin glue (n = 17), formed from human fresh-frozen plasma, enhanced the weld strength decreasing the disruption rate (18%), resulting in an 82% patency which nearly equaled the contralateral sutured vein patency (93%). The bursting strength was improved with fibrin glue. Transmural necrosis was present initially in all groups but extended for a longer distance in the vessel wall in laser-welded anastomoses. Sutured anastomoses exhibited a greater inflammatory response. In laser-welded anastomoses endothelial cells were not as confluent as in sutured anastomoses by six weeks. Carbon dioxide laser-welded end-to-end vein anastomoses appear to be impractical because they disrupt too easily. However, the addition of heterologous fibrin glue to the weld results in a reasonably strong anastomosis with histologic properties that may be beneficial in vein bypass grafts.

The results of treatment after excision of infected arterial grafts were analyzed as a function of aortic/arterial wall cultures and duration of antibiotic therapy in 33 patients. Four patients died during surgery and 29 patients were observed for periods ranging from 2 weeks to 76 months. Negative arterial wall cultures (NAwC) were found in 16 patients, three of whom died of multiple-organ failure and sepsis but none of whom had aortic/arterial disruption/hemorrhage. Positive arterial wall cultures (PAwC) were found in 13 patients, seven of whom received short-term, broad-spectrum antibiotics for less than 10 days (PAwC-STA) and six of whom received long-term culture-specific antibiotic therapy (intravenous therapy for 6 weeks and oral therapy for 6 months) (PAwC-LTA). Five of seven patients in the PAwC-STA group died of aortic disruption or hemorrhage, one patient had severe hemorrhage caused by disintegration of a saphenous vein patch over the common femoral artery, and one patient had a recurrent aortoenteric fistula. There were 10 episodes of arterial disruption/hemorrhage in those seven patients. All episodes of aortic/arterial disruption/hemorrhage occurred in the PAwC-STA subgroup (seven of seven patients) and none occurred in the PAwC-LTA subgroup (none of six patients) (0.005 less than p less than 0.001). The incidence of aortic/arterial disruption/hemorrhage was significantly different between overall PAwC (7 of 13 patients) vs NAwC (none of 16 patients) (0.005 less than p less than 0.001) and NAwC-STA (none of 16 patients) vs PAwC-STA (seven of seven patients) (0.001 less than p less than 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

This study prospectively compared the following tests for their accuracy in amputation level selection: transcutaneous oxygen, transcutaneous carbon dioxide, transcutaneous oxygen-to-transcutaneous carbon dioxide, foot-to-chest transcutaneous oxygen, intradermal xenon-133, ankle-brachial index, and absolute popliteal artery Doppler systolic pressure. All metabolic parameters had a high degree of statistical accuracy in predicting amputation healing whereas none of the other tests had statistical reliability. Amputation site healing was not affected by the presence of diabetes mellitus nor were the test results for any of the metabolic parameters.

Clamping and declamping during aortic surgery produce a hemodynamically significant myocardial stress. The cardiovascular (CV) response to this stress may be adversely altered by calcium antagonists and beta-adrenoreceptor blockade employed to control symptomatic coronary artery disease. This study evaluated the effect of verapamil (V), propranolol (P), and their combination (P + V) on the CV response to infrarenal abdominal aortic cross-clamping and declamping in anesthetized dogs. Six dogs received P as a bolus of 0.5 mg/kg 20 min before clamping. Six additional dogs received V as a 300 micrograms/kg bolus followed by a V infusion of 6 micrograms/kg/min for 20 min before clamping. A third group of six dogs received the P bolus followed 20 min later by the V regimen (P + V). In both the V and P + V groups, 6 micrograms/kg/min V was infused throughout the clamping and declamping sequence. A fourth group of six control dogs received no cardioactive drugs during the experiment. Heart rate, mean aortic blood pressure, left ventricular end-diastolic pressures, peak rate of rise of left ventricular pressure, cardiac output, and systemic vascular resistance were measured in all animals before aortic cross-clamping, at 5 and 40 min after clamping, and 5 min after declamping. The results demonstrated additive negative chronotropic and inotropic properties of P + V therapy with a more significantly adverse effect than that of either drug alone. The implications of this study warrant added caution when patients treated with these drugs undergo abdominal aortic surgery.

Numerous variables are involved in the attachment of endothelial cells to a substrate. Quantifying these factors both on native vessels and on synthetic substrates is important in determining the success of endothelial cell attachment, retention, and growth on these substrates. Fibronectin is an important cell attachment molecule and is likely to be key to the successful attachment of endothelial cells to any substrate. For this reason we have developed an enzyme-linked immunosorbent assay for interrogation of the luminal surface of native and synthetic vessels for the presence of fibronectin. A plexiglass chamber was designed with two blocks, an upper block with wells and a lower supporting block. The chamber was then assembled with a vessel between the two blocks, forming the bottom of the well. This luminal surface was then interrogated by conventional enzyme-linked immunosorbent assay. Native vessels, collagenase-digested vessels, acellular matrices and PTFE preclotted with whole blood were assayed to determine the quantity of fibronectin present. These results were correlated with a bioassay developed to determine the quantity of fibronectin necessary for cell attachment. It was concluded that all of the samples assayed had ample fibronectin for cell attachment and that other factors must be responsible for successful maintenance of a cell monolayer.

A chronic model of venous hypertension was created by iliofemoral venous ligation in the left hindlimb of eight greyhounds (right limb control). Prior to ligation, immediately postligation (T0), and at 2, 4, 6, and 15 weeks postligation (T2-T15), bilateral hindlimb venous pressures were measured at rest. At T2-T15, exercise pressures were measured for 5 min after hindlimb muscle contraction induced under sedation by tetanic (20 sec, 50 Hz, 8 mA) stimulus (S30-S300 sec). Resting and exercise pressures were significantly higher in the ligated hindlimb at all time intervals (resting, P less than 0.001 at T0, T2, T4, T6, and P less than 0.025 at T15; exercise, P less than 0.001 for S30-S300 at T2-T15). In five of the animals at 15 weeks, a cross-femoral venous bypass (CFB) with adjacent adjuvant arteriovenous fistula (AVF) was constructed using autologous external jugular vein. Venous pressures were measured at 2 and 6 weeks post-CFB both at rest and after tetanic muscle stimulation. At 2 weeks, venous pressure in the ligated limb was significantly higher than that in control only after exercise (P less than 0.025 at S30-S120; P less than 0.05 at S150-S180; NS at S240-S300). At 6 weeks, venous pressures were not significantly different at rest or with exercise. All five grafts were patent at 6 weeks. Three of five dogs then successfully underwent ligation of the AVF. At 2 weeks post-AVF ligation there was no difference in resting or exercise venous pressure in the ligated limb compared to control. At 6 weeks post-AVF ligation only two dogs remained for monitoring and in these there was no trend toward venous hypertension in the ligated hindlimb. Graft patency was maintained despite AVF ligation.

Transcutaneous oxygen and carbon dioxide pressure (PO2 and PCO2) foot monitoring was compared with ankle Doppler-derived systolic pressure regarding their respective abilities to discriminate the severity of limb ischemia before vascular reconstruction and to predict surgical outcome early in the postoperative period. Transcutaneous PO2 (tcPCO2), foot-chest tcPO2 index, transcutaneous PCO2 (tcPCO2), foot tcPO2/tcPCO2 index (tcPO2/tcPCO2), ankle Doppler systolic pressure (AP), and ankle-brachial pressure index (ABI) were determined in 89 revascularized limbs. The measurement of tcPO2 and foot-chest tcPO2 was found to be more sensitive to degrees of severity of limb ischemia and more closely associated with the outcome of revascularization than AP and ABI. TcPCO2 and tcPO2/tcPCO2 were not useful in assessment of the vascular patient undergoing reconstructive surgery. Before operation, tcPO2 less than or equal to 22 torr and foot-chest tcPO2 less than or equal to 0.46 indicate severe limb ischemia requiring urgent revascularization. After operation, tcPO2 less than or equal to 22 torr and foot-chest tcPO2 index less than or equal to 0.53 indicate that revascularization is likely to fail. We conclude that tcPO2 monitoring, as a metabolic test of actual tissue perfusion, is a more reliable indicator of preoperative limb ischemia and postoperative outcome of revascularization than hemodynamic, Doppler-derived pressure tests.

This prospective study examined microbiologic features of arterial tissue and pharmacokinetics and bioactivity of cefamandole and cefazolin in patients undergoing elective primary prosthetic aortoiliofemoral/infrainguinal reconstruction. Double-blind, randomized, perioperative prophylaxis (1 gm intravenously every 6 hours for nine doses) with cefamandole or cefazolin was administered to 47 patients. Specimens of blood serum, subcutaneous fat, thrombus, atheroma, and arterial wall were obtained for culture and minimal inhibitory concentration and drug level analysis by high-pressure liquid chromatography. The serum half-life (hr +/- SEM) was 1.43 +/- 0.36 for cefamandole and 2.22 +/- 0.40 for cefazolin. Over the first 2 hours of surgery and for all time intervals combined, the serum concentration of cefazolin was significantly higher (p less than 0.025) than cefamandole. Irrespective of sampling time, the tissue concentration of cefazolin was significantly greater (p less than 0.005) than cefamandole. Positive arterial tissue cultures were obtained in 12 of 29 patients (41.4%) from 23 of 116 (19.8%) arterial tissue specimens. Coagulase-negative Staphylococcus was the predominant isolate, 64 of 93 (68.8%). Twenty-five of the 51 coagulase-negative staphylocci tested (49%) were slime-producers. During surgery, the arterial tissue concentration of cefamandole fell below the geometric mean minimal inhibitory concentration against all organisms combined, and against S. aureus (with the highest minimal inhibitory concentration of the prevalent isolates), significantly more often than the concentration of cefazolin. The data show that a significant number of primary elective aortoiliofemoral/infrainguinal reconstructions are associated with positive arterial tissue cultures, which represent a potential source of graft infection.(ABSTRACT TRUNCATED AT 250 WORDS)

A preliminary assessment was made of the acellular vascular matrix graft as a substrate for endothelial cell seeding, with respect to surface pretreatment (none versus fibronectin and/or serum) and presence of exogenous growth factor. Arteries were harvested from greyhounds and exposed to a sequential detergent extraction process to produce the acellular vascular matrix. Human umbilical vein endothelial cells were grown in tissue culture, harvested in first passage, then seeded at 10(5) cells/cm2 on sections of acellular vascular matrix and on gel-coated polystyrene positive controls. After 18 hour incubation, endothelial cell-seeded acellular matrices were fixed and processed for histologic and planimetric analysis; control wells were fixed and endothelial cells were counted by planimetry. Pretreatment of the acellular vascular matrix was found to have no effect on the percentage of endothelial cell coverage of the matrix. There was significantly better endothelial cell coverage of the acellular matrix than on matched gel-treated polystyrene control wells. Withdrawal of growth factor resulted in a significant reduction in endothelial cell coverage for all acellular vascular matrix groups. Growth factor withdrawal also significantly reduced attachment of endothelial cells on gel-treated polystyrene. Cell surface area was significantly smaller when growth factor was withdrawn from all groups except from the acellular vascular matrix without pretreatment. We conclude that: (1) the acellular vascular matrix is conductive to endothelial cell adherence and spreading even without pretreatment; and (2) sudden withdrawal of exogenous growth factor may impair early coverage of substrates by endothelial cells due to an effect on their adherence or spreading.

A short-term canine model of lower extremity venous hypertension was created to study the hemodynamics of crossfemoral venous bypass grafts (CFB). Specifically, the hemodynamic effects of bypass conduit diameter and adjunctive arteriovenous fistulas (AVFs) were investigated. Unilateral hind limb venous hypertension was produced by iliofemoral venous ligation in six groups of five greyhounds each. Group I had venous ligation alone. CFBs were constructed in the remaining five groups: group II, 3 mm bypass conduit alone; group III, 3 mm bypass plus sequential AVF; group IV, 3 mm bypass plus caudad AVF; group V, 3 mm bypass plus cephalad AVF; group VI, 6 mm bypass conduit alone. Venous hypertension was significantly reduced by CFB (group II, p less than 0.025; group VI, p less than 0.001); increasing the diameter of the bypass conduit from 3 to 6 mm produced significantly greater graft flow (p less than 0.05), while completely relieving venous hypertension. Addition of adjunctive AVFs significantly augmented graft flow (p less than 0.001) but tended to aggravate ipsilateral venous hypertension (group III, p less than 0.01; group IV increase, NSS; group V, p less than 0.001). During the 4 hours of pressure monitoring, venous hypertension diminished significantly (p less than 0.05) with the sequential AVF but not with the other AVF. We conclude that (1) AVFs may be required for adequate graft flow if a small-diameter (3 mm) bypass conduit is used to relieve venous hypertension; (2) adjunctive AVFs aggravate venous hypertension; (3) sequential AVFs seem to be the most hemodynamically efficacious; (4) AVFs may not be necessary if a large, isodiametric (6 mm) conduit is used.

The CO2 laser can weld vessels together and vaporize plaque. This study evaluates its use as an intraluminal reparative tool. In 17 dogs, a 1-cm circumferential intimectomy with a 1-mm distal intimal flap was performed in both carotids. In each dog, one carotid (CON, control) underwent suture flap repair. On the contralateral side (LR, laser repair), the flap was tacked with 20 250-mW 1-sec pulses and the denuded medium was g-lased for 90 sec (250 mW continuous). Animals were randomized into five groups and sacrificed on the day of surgery (Group I, n = 3), at 3 days (Group II, n = 3), at 1 week (Group III, n = 4), at 2 weeks (Group IV, n = 4), or at 4 weeks (Group V, n = 3). Vessel patencies were 88.2 and 82.4% for CON and LR, respectively. Flap repair appeared similar. No aneurysms were noted. Histology revealed a relative absence of platelet adherence to the g-lased surfaces in Groups I and II when compared to that of mechanical methods (CON). The ratio of the thickness of the regenerated surface to the total wall thickness demonstrated hyperplasia in LR vessels (0.54 +/- 0.12) when compared to that in CON (0.30 +/- 0.15) at 2 and 4 weeks (ANOVA, P less than 0.001). Coverage with endothelial-like cells appeared complete at 4 weeks in both methods. The CO2 laser can effectively repair intimal flaps. However, our results demonstrate a significant increase in medial hyperplasia following g-lasing even in the face of minimal early platelet adherence. This may prove detrimental to the long-term patency of intraluminal CO2 laser-treated vessels.

This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost.