Frederick A. Reichle

Prospective comparative clinical trial with distal splenorenal and mesocaval shunts.

In a randomized study, the rate of postshunt encephalopathy was significantly lower after distal splenorenal shunting than after mesocaval shunting. Either shunt can be performed electively with a low operative mortality. If initial hemorrhage cannot be controlled, mortality may be minimized by mesocaval shunting. Advanced cirrhosis is not a contraindication to elective or emergency portasystemic shunting.

Effects of Intraduodenal Administration of HCl and Glucose on Circulating Immunoreactive Secretin and Insulin Concentrations

A new radioimmunoassay for secretin was used to investigate (a) serum secretin responses to intraduodenally infused HCl and glucose, (b) the metabolic half-life and the volume of distribution of exogenous secretin and (c) the effect of endogenously released secretin on insulin secretion in 25 anesthetized dogs. Portal and femoral venous blood samples were taken simultaneously before, during, and after intraduodenal infusion of HCl (21 meq/30 min) and glucose (131 ml/30 min). Control experiments were performed with intraduodenal infusion of saline. Mean portal venous immunoreactive secretin concentration of six dogs rose from 313 muU/ml before to 1,060 muU/ml 10 min after initiation of the intestinal acidification (P < 0.005). Femoral venous immunoreactive secretin concentration rose from 220 muU/ml before to 567 muU/ml 15 min after intestinal acidification (P < 0.01). Secretin concentrations remained elevated during the remainder of the infusion. In the same six dogs mean portal venous immunoreactive insulin concentration rose from 38 muU/ml before to 62 muU/ml at the end of the infusion (P < 0.05). Peripheral immunoreactive insulin, glucose, and free fatty acid concentrations, however, did not change significantly. Pancreatic exocrine function was studied in four dogs. The rise in secretin concentration was followed promptly by a highly significant increase in exocrine pancreatic flow rate and bicarbonate secretion, indicating biological activity of the circulating immunoreactive secretin. The effect of intraduodenal infusion of glucose on immunoreactive secretin concentration was studied in 12 dogs. Glucose in concentrations ranging from 2.5% to 10% had no detectable influence on portal or peripheral secretin concentration. Infusion of 50% glucose caused a slight decline in secretin concentration. The metabolic clearance rate, half-life of disappearance, and volume of distribution of exogenous secretin was studied in three dogs by the constant infusion technic. The metabolic clearance rate was 730+/-34 ml/min, volume of distribution was 17.4+/-0.8% of body weight, and the half-life of disappearance was 2.8+/-0.1 min. It could be calculated that 1.38 U/kg-h(-1) of endogenous secretin was released into the peripheral circulation during the steady state period of the HCl infusion experiments. The data indicated that immunoreactive secretin was released rapidly after intestinal acidification, continued to be secreted throughout the duration of HCl infusion, and was promptly distributed in the extracellular compartment. Furthermore, they suggested that endogenously released secretin could stimulate insulin secretion. The HCl-mediated insulinogenic effect of immunoreactive secretin, however, was too weak to influence peripheral immunoreactive insulin, glucose, and free fatty acid concentrations. The failure of intraduodenal glucose to stimulate secretin release suggests that secretin is not the insulin-stimulatory factor released from the gastrointestinal tract in response to glucose.

Long-term results of femoroinfrapopliteal bypass in diabetic patients with severe ischemia of the lower extremity☆

In patients with severe lower extremity ischemia (ischemic necrosis or pain at rest associated with physical findings of peripheral arterial insufficiency), diabetes mellitus should not deter thorough arteriography and consideration of arterial reconstruction. Infrapopliteal bypass can produce prolonged limb salvage in diabetic patients in lieu of primary amputation.

Infrapopliteal arterial reconstruction in the severely ischemic lower extremity. A comparison of long-term results of peroneal and tibial bypasses.

The feasibility of limb salvage with bypasses to the infrapopliteal arterial tree has been established. In this review, our experience with bypasses to the peroneal artery is compared with that to the tibial arteries. Autogenous saphenous veins were employed in 164 limb salvage arterial revascularizations because of gangrene, ischemic ulceration, or rest pain. These were retrospectively analyzed by the life-table method. Femorotibial (137) or femoroperoneal (27) bypasses were performed on the basis of adequate preoperative arteriograms demonstrating the distal arterial tree, but with no popliteal runoff. Overall operative mortality was 6.1%. Initial limb salvage was 71.2 +/- 3.9% following femorotibial bypass and 51.9 +/- 9.6% after femoroperoneal bypass. Five and seven year cumulative limb salvage rates for femorotibial bypass were 48.5 +/5.2% and 43.4 +/- 6.7%; those for femoroperoneal were equivalent at 38.2 +/- 9.9%. Since long-term limb salvage can be realized in a large number of patients by revascularization of the distal arterial tree, primary amputation is seldom indicated. Operative approach to the ischemic limb must be based on a thorough preoperative arteriogram which demonstrates contrast within vessels down to the distal foot. This is almost always seen and arterial reconstruction is usually feasible. Therefore, limb salvage should be attempted in lieu of primary amputation whether tibial or peroneal arteries are visualized on preoperative arteriogram.

Comparison of Long-term Results of 364 Femoropopliteal of Femorotibial Bypasses for Revascularization of Severely Ischemic Lower Extermities

Successful revascularization of the severely ischemic lower extremity can be achieved by femorotibial as well as femoropopliteal bypass. The incidence of delayed graft occlusion after salvage of the severely ischemic lower extremity is low in patients with femorotibial or femoropopliteal bypass. Femorotibial bypass was performed in over one-third of patients undergoing bypass. Tibial bypasses resulted in effective prolonged revascularization of the severely ischemic lower extremity. An aggressive diagnostic and therapeutic approach to revascularization of the severely ischemic lower extremity can result in prolonged limb salvage by tibial or popliteal bypasses in lieu of primary amputation.

Hemodynamic patterns in human hepatic cirrhosis: a prospective randomized study of the hemodynamic sequelae of distal splenorenal (Warren) and mesocaval shunts.

Increasingly successful operative management of gastroesophageal variceal hemorrhage has been achieved by newer techniques of portal venous reconstruction. Although it is postulated that the clinical success may be due to more selectivity in portal venous shunting, direct determination of the effect of portasystemic shunt on portal vein blood flow has not been possible. Direct determinations of portal vein blood flow were performed preoperative on unanesthetized, hemo-dynamically stable cirrhotic patients by observation of radiopaque water-insoluble droplets. Patients were then randomized into elective distal splenorenal (Warren) or mesocaval shunt and determinations were performed postoperatively under similar conditions when clinically possible. Although portal vein blood flow was not significantly different before (929 ± 147 ml/min) or after 899 ± 271 ml/min) distal splenorenal shunt, there was a large change in portal vein blood flow after mesocaval shunt, decreasing from 772 ± 177 ml/min (hepatopetal) to −1021 ± 310 ml/min (hepatofugal) p < 0.01). After either procedure total hepatic blood flow (as determined by cardiac green clearance) was not significantly changed, nor was renal blood flow; however, cardiac output was significantly increased after mesocaval shunt. Thus the theoretical hemodynamic goals of the selective distal splenorenal shunt, i.e., preservation of the hepatopetal flow within the portal vein, is achieved as determined in the early postoperative period. The correlation between these changes and the eventual clinical outcome remains to be determined.

Redo surgery for graft failure

One of the most vexing problems [1,2] confronting the vascular surgeon is whether or not to reoperate because of graft failure. Graft failures that occur early in the immediate postoperative period often present as limb-threatening emergencies, and a decision must be made whether or not to reoperate. If reoperation is opted for, the question always arises: What can be done to prevent a failure the second time? Although late graft failures may also present as emergencies, they do not carry the threat of a second major operative procedure within a short period of time nor do they carry the implication that there is a technical error or an insoluble problem. The risk of reoperation is considerable, particularly because of the age range of’the patients and the concomitant disease present in so many of the patients who needed reconstructive vascular surgery to begin with. The problem becomes even more acute if surgery was originally done for claudication alone and now, with the sudden occlusion, the limb is threatened. Redo surgery involves consideration of several important factors. The first is the cause of the failure. It is apparent that unless the cause of the failure can be identified and then corrected or eliminated, the reoperative procedure will be failure. As with most situations in medicine, careful attention to detail at the original operation is the best method of preventing failure. It is also important that the patient be given the rather simple instructions to prevent graft occlusion by careful attention to some minimal positional rules. Lastly, attention to the factors of reoperation, the pitfalls, and some of the general technics that can be used is warranted.

Portal vein blood flow determination in the unanesthetized human by umbilicoportal cannulation

Abstract A direct method for quantitation of portal vein flow in the unanesthetized, unsedated human being is described. In patients with normal livers, portal flow decreases following exercise and increases in the postprandial period. In patients with alcoholic cirrhosis there is a trend toward a decreased response of the portal flow to exercise and to oral stimulus of hypertonic glucose. This method is proposed to provide improved preoperative characterization of portal hemodynamics and allow better selection of patients and procedures for decompression of portal venous hypertension in the patient with esophageal variceal hemorrhage.

Blood Flow in the Human Portal Vein A Cineradiographic Method Using Particulate Contrast Medium

A method of assessing portal blood flow (PVF) is presented, employing Lipiodol droplet injection into the portal system via catheterization of a recanalized umbilical vein at cineradiography. Data are given for the average PVF calculated at rest, after exercise, and at twenty, forty, and sixty minutes after a glucose meal in 6 normal unanesthetized patients. Variations in patients with cirrhosis and portal hypertension are described. This method has diagnostic and therapeutic potential in liver disease and offers an opportunity for study of physiological and pathophysiological conditions.

Thrombolysis of acute or subacute nonembolic arterial thrombosis.

The cause of arterial occlusion in patients with peripheral arterial disease is usually atherosclerosis. However, arterial thrombosis is at times associated with the intrinsic arterial disease. Progressive arterial stenosis by atherosclerosis may cause decreased arterial flow and eventual intra-arterial thrombosis. This is manifested clinically as an acute or subacute exacerbation of chronic arterial insufficiency. The objective of this study was to evaluate the capability of thrombolysis by Streptokinase in acute or subacute exacerbations of chronic arterial occlusive disease by randomized single-blind comparison to standard anticoagulant therapy.