Haem oxygenase activity in human umbilical cord and rat vascular tissues.

Carbon monoxide (CO) has been shown to affect vascular tone in smooth muscle cells and thus, may regulate regional or systemic blood pressure as well as fetoplacental vascular tone and fetal blood delivery. To assess the potential of vascular tissue to produce CO, we determined haem oxygenase (HO) activity through in vitro quantitation of CO production with gas chromatography and its inhibition by 33-66 microm of chromium mesoporphyrin (CrMP) in homogenate preparations of rat aorta and vena cava and human umbilical cord tissues. We compared these results to HO activity in rat heart and liver.

A study of nephrotoxin-induced acute tubular necrosis with 31P magnetic resonance spectroscopy.

Phosphorus magnetic resonance spectroscopy (31P MRS) was used to obtain in vivo spectra from rat kidneys undergoing acute tubular necrosis induced by a nephrotoxic dose of cephaloridine (CLD). Spectra were obtained 0, 24, and 48 h after injection of CLD (experimental group, n = 6) or saline vehicle (control group, n = 6). The nephrotoxicity of CLD was demonstrated by severely increased serum creatinine levels and the development of extensive proximal tubular necrosis in the CLD-injected rats, and the lack of such changes in the controls.

Staged infrainguinal revascularization: initial prosthetic above-knee bypass followed by a distal vein bypass for recurrent ischemia. A valid concept for extending limb salvage?

Optimal infrainguinal revascularization should provide limb salvage for the longest duration of time. It is not known whether limb salvage is longer with an initial below-knee popliteal or tibial in situ saphenous vein graft or with staged bypasses; that is, an initial above-knee popliteal prosthetic bypass if feasible, followed by a more distal vein graft should the above-knee prosthetic graft fail. A retrospective review of 197 lower extremity vascular reconstructions performed since 1976 utilizing polytetrafluoroethylene (PTFE), umbilical vein, or in situ saphenous vein was completed.

Efficacy of tissue plasminogen activator and urokinase in a canine model of prosthetic graft thrombosis.

Tissue plasminogen activator and urokinase were evaluated in a model of prosthetic graft thrombosis. In addition, the effects of thrombus age on lysability and the effect of thrombolytic agents on endothelium were examined. Polytef (polytetrafluoroethylene [PTFE]) grafts (3 mm X 3.

The natural history of endothelial structure and function in arterialized vein grafts.

When the saphenous vein is used in the in situ position for arterial bypass surgery, it is associated with more optimal preservation of the endothelial lining and with improved graft patency compared with reversed vein grafts. However, it is not clear whether preservation of endothelial integrity persists after arterialization. The goal of this study was to establish whether preservation of the endothelium before arterialization is a critical factor in the development of late functional and morphologic abnormalities of autogenous vein grafts.

The role of computed tomography in symptomatic aortic aneurysms.

Forty-seven patients with an abdominal aortic aneurysm (AAA) and recent onset of abdominal or back pain were evaluated by emergency computed tomography (CT) to identify those patients with a confined rupture, and unstable aneurysm, nonaneurysmal cause of pain and a stable AAA. CT suggested that 25 per cent of these had a confined rupture and should undergo emergency surgical treatment. Rupture was confirmed at operation in one-half of these instances.

Venous stasis ulceration. Effectiveness of subfascial ligation.

Forty-seven extremities with recurrent venous ulceration were treated by subfascial ligation of incompetent perforating veins. The limbs were observed for an average of 8.5 years (range, 0.

In situ saphenous vein bypass grafts for limb salvage. A current fad or a viable alternative to reversed vein bypass grafts?

Revascularization of the lower extremity using the in situ saphenous vein bypass graft has resurfaced as a clinical alternative to reversal of the saphenous vein. Early patency rates have been excellent, however, concern has been raised about the durability of the in situ technique. Our total experience with this technique has been reviewed to evaluate its effectiveness on a teaching vascular service.

Intrahepatic pyogenic abscesses: treatment by percutaneous drainage.

During a 6 year period, 18 liver abscesses in 12 patients were identified by computerized tomography. Five patients had presumed hematogenous seeding. Five patients previously had bilioenteric anastomoses, stents, or both to relieve obstructive jaundice.

Expanded criteria for percutaneous abscess drainage.

The original criteria for percutaneous abscess drainage were limited to simple abscesses (well-defined, unilocular) with safe drainage routes. We expanded these entry criteria to include complex abscesses (loculated, ill-defined, or extensively dissecting abscesses), multiple abscesses, abscesses with enteric fistulas or whose drainage routes traversed normal organs, as well as complicated abscesses (appendiceal, splenic, interloop, and pelvic). Using these expanded criteria, cure was achieved nonoperatively in 92 (73.

Luminal release of prostacyclin and thromboxane A2 by arteries distal to small-caliber prosthetic grafts.

Myointimal hyperplasia distal to prosthetic grafts may be due to a local imbalance of prostacyclin and thromboxane A2 that exaggerates platelet adherence. This study evaluated prostacyclin and thromboxane A2 production by arteries distal to prosthetic grafts. In 12 dogs, control segments of both iliac arteries were excised and a 5 cm segment of polytetrafluoroethylene was grafted end to end.

Percutaneous drainage of infected pancreatic pseudocysts.

After diagnostic needle aspiration guided by computed tomography and/or ultrasound, 11 infected pseudocysts in ten patients were treated nonoperatively by percutaneous catheter drainage and intravenously administered antibiotics. Nine infected pseudocysts resolved after 11 to 37 days (mean, 21 days) with no recurrences at follow-up 16 to 42 months (mean, 24.4 months) later.

Functional injury of vein graft endothelium. Role of hypothermia and distention.

The cause of endothelial injury during vein harvesting and preservation is complex. Hypothermia is thought necessary to preserve cell viability but has been implicated in morphologic injury to the endothelium. This study explored the effect of temperature on preserving endothelial function using prostacyclin production as a metabolic marker.

Stroke after carotid endarterectomy: risk as predicted by preoperative computerized tomography.

In patients undergoing carotid endarterectomy, the role of preoperative computerized tomographic head scanning in predicting the risk of postoperative neurologic deficit was determined by a retrospective evaluation of a select group of 107 consecutive patients with preoperative scans. Patients with infarction determined preoperatively by computerized tomography were found to be at a significantly higher risk for postoperative neurologic deficit than patients with a normal preoperative computerized tomographic scan. History and physical examination alone detected only 66 percent of the infarctions found with preoperative computerized tomographic scanning in these patients.

Favorable balance of prostacyclin and thromboxane A2 improves early patency of human in situ vein grafts.

Graft thrombosis soon after reconstruction remains a major obstacle to the use of reversed vein grafts in infrapopliteal reconstruction. Our clinical experience with in situ vein grafts corroborates Leather's results by demonstrating an overall graft patency of 95% below the knee at 1 year and 94% in the infrapopliteal group. It has been postulated that this improved early patency rate of in situ vein grafts is the result of more optimal preservation of the endothelium of the vein graft.

Combined operative angiodilation and arterial reconstruction for limb salvage.

Fifteen high-risk patients with threatened limb loss underwent combined operative iliac angiodilation and infrainguinal vascular reconstruction for iliac and femoropopliteal occlusive disease. The patients were poor candidates for combined surgical inflow and outflow reconstruction because of associated cardiopulmonary disease. The mean systolic pressure gradient across the iliac stenosis was 34 +/- 5 mm Hg.

Prevalence of normal serum amylase levels in patients with acute alcoholic pancreatitis.

Acute alcoholic pancreatitis is uncommonly diagnosed when the serum amylase level is normal. We defined acute alcoholic pancreatitis as a clinical syndrome in which hyperamylasemia was not a necessary component and sought support for the diagnosis by ultrasonography and computed tomography of the pancreas. In 68 episodes of acute alcoholic pancreatitis identified in a one-year period, the serum amylase level was normal at the time of hospital admission in 32%.

Gastric carcinoid (gastrinoma) associated with achlorhydria (pernicious anemia).

This report presents a case of multicentric gastric carcinoid (gastrin containing) tumors of the fundus associated with achlorhydria and pernicious anemia. It is suggested that stimulation of the antral G cells and possibly fundic argyrophilic cells by achlorhydria associated with atrophic gastritis may lead to hyperplasia, and eventually to neoplasia in the latter, in the form of gastric carcinoid with gastrin production.

Direct venous surgery for venous valvular insufficiency of the lower extremity.

Seven patients had severe deep venous insufficiency and recurrent ulceration in eight lower extremities. All incompetent perforating veins had been previously ligated. All limbs were evaluated by dynamic venous pressure measurements.

Distal in situ saphenous vein grafts for limb salvage. Increased operative blood flow and postoperative patency.

Early failure remains a major obstacle to successful distal bypass surgery using vein grafts for limb salvage. Thirty distal bypass graft procedures were performed for limb salvage using the in situ technique. Grafts were anastomosed to the distal popliteal artery in 13 patients and to the infrapopliteal artery in 17 patients.

Lethal complications associated with nonrestrictive treatment of abdominal aortic aneurysms.

Five high-risk patients received nonresective treatment of abdominal aortic aneurysms (AAAs). This treatment included ligation of the iliac arteries to induce acute thrombosis of AAA and a simultaneous axillobifemoral bypass for restoration of arterial flow to the lower extremities. Of these five patients, lethal complications associated with this procedure developed in four.

Reduced metabolic complications in total parenteral nutrition: pilot study using fat to replace one-third of glucose calories.

The limitations of glucose-based TPN solutions are high glucose concentration, high osmolality, lack of fat, and essential fatty acids, which result in glucose intolerance and hepatotoxic effects. We replaced one-third of the calories in a standard amino acid-glucose solution with Liposyn 10% for 14 days in 23 critically ill men who needed total parenteral nutrition. Serial measurements included weight, albumin, glucose, triglyceride concentrations, and liver function tests.

Cause of wound complications in elderly patients with above-knee amputation.

Seventy-six above-knee amputations performed on elderly debilitated patients were reviewed. Fifty-one wounds healed without complications; 25 amputation wounds developed postoperative complications. The quality of the femoral pulse has a significant effect on wound healing after an above-knee amputation.