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Objective Patients with abdominal aortic aneurysms (AAAs) who are surgical candidates have as many as three options: open surgery, endovascular surgery, or no surgery. As with all treatment decisions, informed patient preferences are critical. Decision support tools have the potential to better inform patients about the risks and benefits associated with each treatment option and to empower patients to participate meaningfully in the decision-making process. The objective of this study was to develop and pilot test a decision support tool for patients with AAAs. Methods We developed a personalized, interactive, computer-based decision support tool reflecting the most current outcomes data and input from surgeons and patients. We piloted the tool with AAA repair candidates who used the tool prior to meeting with their surgeon. Patients were recruited from a university-based vascular surgery clinic and affiliated VA hospital clinic. To determine feasibility and acceptability, the following outcomes were measured: (1) percent of patients who agreed to participate, (2) length of time required to use the tool, (3) the amount of assistance required to use the tool, and (4) patients' opinions on the acceptability of the tool. To assess effectiveness of the tool, we measured change in knowledge and decisional conflict pre- and post-tool using the paired t -test. Results One hundred percent of patients who were approached (n = 12) agreed to participate in the study. The tool was administered in a median time of 35 minutes (range, 25-45 minutes), and all patients were able to navigate the program with minor technical assistance. Mean knowledge scores increased from 56% to 90% ( P = .005), and decisional conflict scores decreased from 29% to 8% ( P = .04). Overall, patients reported that the program content was balanced across treatment options, presented information clearly and concisely, helped them to organize their thoughts about the decision, and prepared them to talk to their surgeon about what mattered most to them. Conclusions Preliminary evidence suggests that use of an evidence-based AAA decision support tool is feasible and acceptable to patients, increases knowledge, and decreases decisional conflict. Widespread use of such a tool might improve the content and quality of informed consent for this difficult treatment decision.

Background Declining interest in careers in surgery among medical students has contributed to growing concerns about the surgical workforce. Although the medical student clerkship is likely to play an important role in shaping students' impressions of careers in surgery, little is known about the nature of this process. This study was designed to identify those aspects of the clerkship that are associated with medical students expressing an interest in surgery at the end of the clerkship. Study Design Medical students completed a survey at the end of the surgical clerkship assessing characteristics of the clerkship experience and students' level of interest in pursuing a career in surgery. The survey also included open-ended questions about students' reasons for having increased or decreased interest in surgery, which were systematically analyzed to complement quantitative findings. Results Students who sutured (p = 0.001), drove the camera (p = 0.01), stated that they felt involved in the operating room (p = 0.009), and saw residents (p = 0.03) and attendings (p = 0.0003) as positive role models were more likely to be interested in surgery. After adjusting for covariates, students who sutured in the operating room were 4.8 times as likely to be interested in surgery (95% CI, 1.5 to 14.9) and students who drove the camera were 7.2 times as likely to be interested in surgery (95% CI, 1.1 to 46.8). Conclusions Students who participate actively in the operating room and those who are exposed to positive role models are more likely to be interested in pursuing a career in surgery. To optimize students' clerkship experiences and attract top candidates to the field of surgery, clerkship directors should encourage meaningful engagement of students in the operating room and facilitate mentoring experiences.

Despite the risks associated with renovascular hypertension and the durable benefits of revascularization, the detection of patients with renovascular hypertension and the selection of those who will benefit from interventional therapy remains a challenge. We have previously documented the reliability of captopril renal scintigraphy in predicting angiographically significant renal artery stenosis in patients suspected of having renovascular hypertension. In the present study we report our recent experience with this noninvasive technique in predicting outcome after revascularization. Captopril renal scintigraphy involves the administration of 50 mg of captopril 3 hours after a baseline technitium-99m diethylenetriaminepentaacetic acid renal scan and 1 hour before a repeat captopril renal scintigraphy scan. Nineteen of the last 70 patients with clinically suspected renovascular hypertension undergoing captopril renal scintigraphy had abnormal renal scan outcomes, and 17 had a decrease in flow or function after captopril (positive captopril renal scintigraphy). Eight of these 17 with abnormal findings on captopril renal scintigraphy underwent revascularization, and the hypertension was cured or improved in six of the eight: two of three after surgical bypass grafting and four of five after angioplasty. In the seven surviving patients with abnormal renal scan results but no change with captopril (negative captopril renal scintigraphy), improvement in hypertension after treatment occurred in only one: one of two after nephrectomy, zero of three after bypass surgery, and zero of two after angioplasty (p less than 0.05). We conclude that captopril renal scintigraphy is an accurate predictor of hypertension response to revascularization. Further evaluation of this new noninvasive technique for assessing patients with suspected renovascular hypertension appears warranted.

Three hundred twenty-five cases of spontaneous aortic dissection seen at two institutions between 1965 and 1986 were reviewed to assess the incidence, morbid sequelae, and specific management of aortic branch compromise. Noncardiac vascular complications occurred in 33% of the study group, and in these patients the overall mortality rate (51%) was significantly (p less than 0.001) higher than in patients without (29%) such complications. Although aortic rupture was the strongest correlate of mortality (90%), death specifically related to vascular occlusion was common when such occlusion occurred in the carotid, mesenteric, and renal circulation. There was a strong correlation between stroke and carotid occlusion (22/26 cases), yet specific carotid revascularization was only used during the chronic phase of the disease. Similarly, peripheral operation was ineffective in reducing the mortality rate in the setting of mesenteric (87%) and renal (50%) ischemia. Fifteen patients required either fenestration or graft replacement of the abdominal aorta for acute obstruction, rupture, or chronic aneurysm development. Thirty-eight patients (12%) demonstrated some degree of lower extremity ischemia, and one third of these required a direct approach on the abdominal aorta or iliofemoral segments to restore circulation. Selected patients with acute aortic dissection may require peripheral vascular operation in accordance with a treatment strategy that directs initial attention to the immediate life-threatening complications.

With the organ-balance technique, we studied amino acid and glucose metabolism by hepatic and extrahepatic splanchnic tissues in awake dogs in the postabsorptive state and during a 3-h intravenous amino acid infusion. Dogs received a high (1.4 g/kg body wt, n = 5) or low (0.7 g/kg body wt, n = 8) dose of amino acids. In four of the latter dogs, the dose was delivered into a mesenteric vein. During the basal period there was a net removal of gluconeogenic amino acids (particularly alanine), but not branched-chain amino acids, and a net production of glucose by the liver in all dogs. During this time there was a net removal of glucose and production of alanine by the extrahepatic splanchnic tissues. During either high- or low-dose amino acid infusion, net hepatic glucose release increased; despite this, arterial plasma glucose declined due to an increase in tissue glucose uptake at extrasplanchnic sites. The net amount of glucogenic amino acids removed by the liver during high-dose (9.1 ± 1.0 mmol · kg−1 · 3 h−1) and low-dose (4.8 ± 0.6 mmol · kg−1 · 3 h−1) infusion equaled or exceeded the infused load of these amino acids. In addition, the liver contributed to the net disposal of branched-chain amino acids during high-dose (536 ± 147 μmol · kg−1 · 3 h−1) and low-dose (341 ± 70 μmol · kg−1 · 3 h−1) infusion. During high-dose infusion, extrahepatic splanchnic tissues participated in the net removal of branched-chain amino acids (436 ± 162 ¼mol · kg−1 · 3 h−1) but not glucogenic amino acids, and net alanine production continued (410 ± 91 μmol · kg−1 · 3 h−1). The route (peripheral or mesenteric) did not appear to influence the subsequent disposal of the amino acid load. We conclude that during intravenous amino acid administration in the dog, the splanchnic bed is the major site of net amino acid disposal. The liver contributes to the net disposal of both glucogenic and branched-chain amino acids, whereas extrahepatic splanchnic tissue contributes to the net disposal of only the branched-chain amino acids. Overall, only 10–15% of the total infused amino acids was removed by extrasplanchnic (peripheral) sites, despite increased concentrations of plasma amino acids and elevated plasma insulin concentrations. These tissues may replete nitrogen stores during feeding by mechanisms other than removal of circulating amino acids.

Between 1975 and 1983, 303 cirrhotic patients with endoscopically proven major variceal hemorrhage were admitted to the participating hospitals of the Boston-New Haven Collaborative Liver Group. Of these, 274 were evaluated for admission to a prospective, randomized controlled trial comparing portal-systemic shunts with distal splenorenal shunts. The criteria for inclusion were as follows: (i) a portohepatic pressure gradient ≥ 12 mmHg; (ii) angiographic evidence of antegrade portal venous flow; (iii) angiographic demonstration that the inferior vena cava and portal, splenic and left renal veins were anatomically suitable for either a portal-systemic or distal splenorenal shunt, and (iv) the patient was a reasonable operative risk. Eighty-one patients from the six participating hospitals fulfilled the criteria and consented to participate. Thirty-eight patients were randomly assigned to have portal-systemic shunt and 43 to have distal splenorenal shunt. After a follow-up period of 11 years (mean = 3.5 years for all patients), survival was found to be similar in the two groups of patients. The 30-day operative mortality was 13% for the portal-systemic shunt group and 9% for the distal splenorenal shunt patients. Late mortality was 55% for the portal-systemic shunt and 37% for the distal splenorenal shunt group. Total mortality was 68% for the portal-systemic shunt and 46% for the distal splenorenal shunt group. None of these differences is statistically significant. In those patients who survived >30 days after surgery, recurrent variceal hemorrhage occurred in four (12%) in the portal-systemic shunt group compared to seven in the distal splenorenal shunt group (18%) (NS). Portal-systemic encephalopathy occurred in 15 (45%) of the operative survivors in the portal-systemic shunt group compared to 20 (51%) in the distal splenorenal shunt group. Severe portal-systemic encephalopathy was observed with equal frequency in the two groups. There was no difference in the time of onset nor the severity of encephalopathy in the two groups. We conclude that the operative mortality and cumulative survival are similar for the two operations and that the frequency and severity of hepatic encephalopathy following distal splenorenal shunt are similar to that after portal-systemic shunt. Based on our observations and previously published data, recurrent hemorrhage from varices appears to be more frequently prevented by portacaval anastomosis than by distal splenorenal shunt.

Endoscopic sclerotherapy has been widely advocated as primary therapy for patients surviving hemorrhage from esophageal varices. The potential for endoscopic sclerotherapy to limit subsequent surgical options remains unclear. The following study was undertaken to assess the endoscopic sclerotherapy—related incidence of splanchnic venous thrombosis in patients undergoing surgery for variceal bleeding. We retrospectively identified 27 patients who underwent portosystemic shunting after an episode of variceal hemorrhage documented by endoscopic examination. Eleven patients underwent endoscopic sclerotherapy before portosystemic surgery for shunting. Among the patients undergoing prior endoscopic sclerotherapy, 6/11 had partial splanchnic venous thrombosis at surgery compared with 2/16 in the non-endoscopic sclerotherapy group. This difference was statistically significant. Only one of the eight patients with splenic or portal vein thrombosis detected at surgery showed signs of the condition when an angiograph was performed. Endoscopic sclerotherapy appears to impose a significant risk for splanchnic venous thrombosis. This complication, not reliably detected by angiographic means, may limit the operative options and long-term outcomes of patients in whom endoscopic sclerotherapy fails. (J Vasc Surg 1989;10:9–13.)

A 47-year-old man with heterozygous factor V Leiden disorder and intermittent hyperhomocysteinemia developed spontaneous acute popliteal artery thrombosis. Homocysteine levels were above normal limits at presentation. Intra-arterial thrombolysis was used successfully to treat the acute thrombosis; long-term treatment included anticoagulation, folic acid, and risk factor modification. Although factor V Leiden is strongly associated with deep venous thrombosis, additional cofactors such as hyperhomocysteinemia may predispose to an increased risk of acute arterial thrombosis in areas of pre-existing peripheral arterial disease.

A primary abdominal aortic dissection was encountered in a 53-year-old hypertensive man who was admitted with a 2-week history of back pain. Treatment with an infrarenal aortic bifurcation graft complemented by reconstruction of the proximal aortic cuff was curative.

A prospective controlled comparison of portal-systemic (PSS) and distal splenorenal shunts (DSRS) in cirrhotic patients who had survived hemorrhage from esophagogastric varices was undertaken 5 yr ago at five hospitals by the Boston-New Haven Collaborative Liver Group. The clinical and endoscopic criteria for massive hemorrhage were satisfied in 155 patients. Thirty-four patients were excluded, primarily because of uncontrolled hemorrhage. Thirty-four were rejected because they were poor operative risks and 21 because they did not satisfy criteria. Thirteen patients refused to participate; the remaining 53 were randomized; 29 to receive PSS and 24, DSRS. The two groups were similar in clinical, laboratory, and manometric characteristics. The DSRS group was older and tended to have had more previous hemorrhages. Followup ranged from 1 to 56 months (mean 21). After PSS, which was performed by 10 different surgeons, 6 patients died during the hospital admission (21%) compared to 2 after DSRS (12%). There were 6 late deaths in the PSS group and 4 in the DSRS group. Portal-systemic encephalopathy occurred in 5 of the 23 survivors of PSS (23%), and in 6 of the 19 who survived DSRS (32%). Two patients in the PSS group bled (9%), 1 after thrombosis and 1 after stenosis of the shunt. Three patients in the DSRS group bled (16%) and all had thrombosis of the shunt. PSS was associated with an unexplained but inordinately high operative mortality. Although the DSRS was accomplished with an acceptably low operative mortality, it was associated with frequent portal-systemic encephalopathy, shunt occlusion, and recurrent hemorrhage. Similar incidences of portal-systemic encephalopathy, shunt occlusion, and recurrent hemorrhage were observed in the PSS group. More patients and longer followup are necessary to determine which of these portal decompressive procedures is superior.

We reviewed 142 percutaneous transluminal angioplasties (PTAs) in the iliac (n = 94) and femoropopliteal (n = 48) positions of 107 patients. Emphasis was placed on the ultimate clinical outcome, which was determined from a pool of clinical, hemodynamic, and angiographic data. Limb-threatening ischemia was the indication for intervention in 53% of the cases. The median follow-up interval was 17 months. Overall success was achieved in 50% of cases in both iliac and femoral positions at one year after PTA. The following factors were found to correlate with a successful clinical outcome: PTA for claudication vs limb-threatening ischemia (P less than .001); focal as opposed to diffuse stenosis or occlusion (P less than .02); immediate return of distal pulses (P less than .001); the absence of diabetes (P less than .05); and the presence of a patent outflow tract (P less than .001). Treatment results with PTA will vary widely according to the nature of the patient population and the criteria for determining success.

Triglycyl-lysine vasopressin (tGLVPP) is activated in the circulation when the N-triglycyl residue of the molecule is cleaved by endothelial peptidases, releasing lysine vasopressin. We compared the effect of an intravenous bolus dose of tGLV (20 micrograms/kg) with a constant infusion (2.75 mU/kg/min) of arginine and lysine vasopressin (Pitressin) in normal mongrel dogs. Portal pressure was artifactually increased by a constricting flow probe. Baseline values were similar in both groups; at the time of near-maximal reduction in portal pressure, both drugs equally reduced portal venous pressure (38 +/- 4 vs 39 +/- 4%), superior mesenteric arterial blood flow (40 +/- 8 vs 39 +/- 9%), portal venous flow (35 +/- 4 vs 40 +/- 5%), and heart rate (9 +/- 2 vs 11 +/- 7%. Cardiac output obtained 10-30 min after tGLVP administration was similar that of VP, and each drug reduced cardiac output significantly when compared with its own baseline (18 +/- 4 vs 21 +/- 7%). Mean arterial pressure increased similarly with both drugs (11 +/- 3 vs 11 +/- 3%). The only difference observed was the hepatic arterial flow response. While tGLVP increased HAF 34 +/- 11%, the physiologic autoregulatory response to a decrease in portal venous flow and pressure; vasopressin was associated with no such compensatory response (1 +/- 6%). Whether this advantage of tGLVP and its more prolonged reduction of portal venous pressure (mean 103 min) are beneficial in the clinical setting requires additional studies.

In awake dogs we measured the glucose balance across the liver and extrahepatic splanchnic tissues in the postabsorptive state and during two hours of IV infusion of glucose or for three hours following ingestion of oral glucose and during four hours of sequential intraportal followed by oral glucose. The IV glucose infusion rate was adjusted to maintain a steady state glucose concentration of either euglycemic levels (insulin clamp, group 1, N = 4), 125 mg/100 mL above the postabsorptive glucose concentration (+125 mg glucose clamp, group 2, N = 3) or 200 mg/100 mL above basal glucose levels (+200 mg glucose clamp, group 3, N = 7). Oral glucose was given at a dose of either 1.5 g/kg (group 4, N = 7) or 2.5 g/kg (group 5, N = 12). In dogs that received IV glucose, basal gut glucose uptake (0.5 +/- 0.1 mg/min X kg) was stimulated by hyperglycemia (1.5 +/- 0.5 and 1.4 +/- 0.1 mg/min X kg for group 2 and 3, respectively, P less than 0.05). In these same animals basal hepatic glucose output (-2.7 +/- 0.3 mg/min X kg) was promptly suppressed and net hepatic glucose uptake occurred (2.8 +/- 0.2 and 2.4 +/- 0.5 mg/min X kg in group 2 and 3 respectively). Euglycemic hyperinsulinemia (group 1) suppressed postabsorptive hepatic glucose release but did not enhance glucose removal by either the liver or gut tissues. After oral glucose gut tissues released absorbed glucose into portal blood. Over three hours following the glucose meal 74% and 59% of the ingested glucose was absorbed in group 4 and 5, respectively. As with IV glucose, postabsorptive hepatic glucose production was suppressed and over the first two hours after feeding the liver took up glucose (3.4 +/- 1.0 and 3.1 +/- 0.7 mg/min X kg groups 4 and 5, respectively) at a rate similar to that seen with IV glucose. To further examine the effect of the route of glucose administration on liver glucose handling, hepatic glucose balance was measured serially over four hours in three dogs that received IV glucose into a mesenteric vein to produce portal hyperglycemia (+125 mg/dL portal glucose clamp N = 3). Oral glucose (2.5 mg/kg) was given at two hours, and the rate of the mesenteric glucose infusion adjusted to maintain portal glycemia constant. The hepatic glucose balance averaged 5.5 mg/min X kg over the 0 to 2 hour period and 4.2 +/- 1.0 mg/min X kg over the 2 to 4 hour time.(ABSTRACT TRUNCATED AT 400 WORDS)

Aortic thrombosis occurring after blunt abdominal trauma is a rare but recognized event. Most of these patients present with progressive and profound neurologic compromise. Successful management requires early diagnosis, maintenance of hemodynamic stability, and prompt revascularization. Despite appropriate management a large percentage of these patients (unprotected by heparin or collateral vessels) will remain paraplegic. (J VASC SURG 1987;6:412-4.)

• Recent demographic and biochemical studies have suggested that there may be significant differences in the population of patients undergoing reconstruction for an aortic aneurysm (AA) or atherosclerotic occlusive disease (OCC) of the abdominal aorta. The purpose of this retrospective study was to compare the results of aortic surgery in these different patient groups. One hundred three patients undergoing aortic grafting were reviewed. Twenty-four patients underwent reconstruction for OCC, 65 electively for asymptomatic aneurysms (EAA), and 14 for ruptured aortic aneurysms (RAA). The mean age for OCC patients (54 years) was significantly lower than that for EAA (68 years) or RAA patients (71 years). Patients with AA were predominantly male (92%) compared with those with OCC (62%). Despite the age and sex differences, there were no significant differences between the groups in the incidence of cardiac disease, hypertension, smoking history, diabetes mellitus, or renal or pulmonary disease. In addition, there were no significant intraoperative differences in terms of operative and clamp times, fluid administration, urine output, hypotension, or subsequent postoperative morbidity and mortality. We conclude that despite AA and OCC patients being demographically distinct, there is essentially no difference in elective aortic bifurcation graft surgery between these two populations. ( Arch Surg 1985;120:817-819)

• Systemic mastocytosis is characterized by an abnormal proliferation of tissue mast cells. Though rarely a surgical disease, it occasionally presents as variceal bleeding secondary to portal hypertension. Ultrastructural studies of the liver and spleen and portal pressure measurements support the hypothesis that a perisinusoidal intrahepatic fibrosis is responsible for the increased portal pressure. When variceal bleeding complicates systemic mastocytosis, shunt surgery is indicated, with the type of shunt dictated by both hematologic and hemodynamic issues. Satisfactory blockade of histamine release can be achieved preoperatively by disodium cromoglycate and/or histamine antagonists to obviate any systemic effects precipitated by shunting of mast cell—rich splenic blood into the systemic circulation. (Arch Surg1988;123:767-769)

• Infection of the femoral artery results in false aneurysm formation and hemorrhage unless appropriate reconstructive measures are taken. We reviewed ten such cases managed by obturator canal bypass with autogenous saphenous vein. The graft maintained viability of the extremity in every case in the early postoperative period. One death occurred related to cardiac disease, and there was one late failure. This experience confirms the usefulness of the obturator canal as a method for bypass of the infected femoral artery. ( Arch Surg 114:1031-1033, 1979)

Objective Whether or not to undergo surgery for abdominal aortic aneurysm (AAA), and whether to have open or endovascular repair (EVAR), is a complex decision that relies heavily on patient preferences, and yet little is known about the patient perspective on informed consent in this context. This study explores patients' views on their decision-making processes and the quality of surgeon-patient communication during informed consent for AAA repair. Design of study We conducted in-depth interviews with AAA patients (n = 20) who underwent open AAA repair, endovascular repair, or declined surgery. Data were independently transcribed and analyzed by a team of individuals with diverse backgrounds, using the constant comparative method of analysis and systematic coding procedures. Setting Patients who had seen surgeons from academic, private practice, and VA settings were interviewed. Main outcome measure Patients' opinions regarding the nature, scope, and content of informed consent for AAA repair. Results We identified four central themes characterizing patients' experiences with informed consent for AAA repair: 1) patients did not appreciate the scope of their options; 2) patients demonstrated that they were not adequately informed prior to making a decision; 3) patients differed in the scope and content of information they desired during informed consent; and 4) trust in the surgeon had an impact on the informed consent process. Conclusion Our research highlights the limitations of the informed consent encounter in the current clinical context, and points to several ways in which informed consent could be improved. Adapting the informed consent encounter to incorporate the patient's perspective is critical in order to ensure that the decision regarding AAA repair is consistent with the patient's informed preference.