Myocardial infarction after vascular surgery: the role of prolonged stress-induced, ST depression-type ischemia.

OBJECTIVES: The goal of this study was to investigate the nature of the association between silent ischemia and postoperative myocardial infarction (PMI). BACKGROUND: Silent ischemia predicts cardiac morbidity and mortality in both ambulatory and postoperative patients. Whether silent stress-induced ischemia is merely a marker of extensive coronary artery disease or has a closer association with infarction has not been determined. METHODS: In 185 consecutive patients undergoing vascular surgery, we correlated ischemia duration, as detected on a continuous 12-lead ST-trend monitoring during the period 48 h to 72 h after surgery, with cardiac troponin-I (cTn-I) measured in the first three postoperative days and with postoperative cardiac outcome. Postoperative myocardial infarction was defined as cTn-I >3.1 ng/ml accompanied by either typical symptoms or new ischemic electrocardiogram (ECG) findings. RESULTS: During 11,132 patient-hours of monitoring, 38 patients (20.5%) had 66 transient ischemic events, all but one denoted by ST-segment depression. Twelve patients (6.5%) sustained PMI; one of those patients died. All infarctions were non-Q-wave and were detected by a rise in cTn-I during or immediately after prolonged, ST depression-type ischemia. The average duration ofischemia in patients with PMI was 226+/-164 min (range: 29 to 625), compared with 38+/-26 min (p = 0.0000) in 26 patients with ischemia but not infarction. Peak cTn-I strongly correlated with the longest, as well as cumulative, ischemia duration (r = 0.83 and r = 0.78, respectively). Ischemic ECG changes were completely reversible in all but one patient who had persistent new T wave inversion. All ischemic events culminating in PMI were preceded by an increase in heart rate (delta heart rate = 32+/-15 beats/min), and most (67%) of them began at the end of surgery and emergence from anesthesia. CONCLUSIONS: Prolonged, ST depression-type ischemia progresses to MI and is strongly associated with the majority of cardiac complications after vascular surgery.

Successful renal transplantation from two donors with methanol intoxication.

Two patients with acute methanol intoxication are reported, one with acute renal failure. Both were declared brain-dead and kidneys were harvested at 80 and 130 hr after hospital admission. All four kidneys were transplanted and subsequently functioned well. In both donors who had received ethanol treatment, thrombocytopenia was present. The reluctance to use kidneys from such donors and from donors with acute renal failure before harvesting is discussed. Waiting lists for renal transplantation are growing and there is a world-wide shortage of cadaver organs. We were recently surprised to find reluctance to consider two local patients dying from methanol intoxication as suitable organ donors, and we report the outcome of four kidneys transplanted from these donors. We were unable to find any similar cases reported in the English literature.

Transient neurological events during dipyridamole stress test: an arterial steal phenomenon?

Dipyridamole-associated adverse neurological side effects have not been extensively described. We present two cases of dipyridamole-associated transient motor neurological events with no evidence of residual neurological deficits detected clinically or by head CT. The patients showed no evidence of significant extracranial (internal carotid) artery disease. We propose the presence of a regional cerebral perfusion disturbance due to an intracranial vascular steal phenomenon as the mechanism for the above side effects of dipyridamole.

Bacterial adherence to endothelial-seeded polytetrafluoroethylene grafts.

Since infections of an arterial prosthesis pose a serious threat to life and limb, efforts to produce a graft that is resistant to hematogenous bacteremia continue. We studied the effect of endothelial seeding on bacterial adherence to polytetrafluoroethylene grafts in a canine model. Enzymatically derived venous endothelial cells were seeded in 10 cm long, 4 mm inner diameter polytetrafluoroethylene grafts, which were then implanted as carotid interpositions opposite contralateral unseeded controls. After 4 to 8 weeks, each dog received an intravenous infusion of 3 X 10(8) radiolabeled Staphylococcus aureus. Seeded grafts had significantly fewer adherent viable bacteria than had control grafts (mean, 432 versus 989; p less than 0.05) and significantly fewer radiolabeled bacteria (mean, 2 X 10(5) versus 8 X 10(5); p less than 0.05). Seeded grafts also had significantly more thrombus-free, luminal surface area than had control grafts (mean, 72% versus 40.6%; p less than 0.05). Scanning electron microscopy and autoradiography of seeded grafts confirmed that the sites of bacterial adherence largely corresponded to accumulations of surface thrombus. In this experiment, endothelial seeding appeared to protect against bacterial adherence after a hematogenous challenge 4 to 8 weeks after implantation by reducing luminal thrombi.

Small paraduodenal hernias.

During an 18-month period, five patients ranging in age from 3 1/2 to 79 years old were treated for small paraduodenal hernia. Three had acute strangulated obstruction, while in the other two patients the hernia was found incidentally, during surgery for other causes. As the mortality of obstructing internal hernias exceeds 50%, all paraduodenal hernias, even small and asymptomatic ones, should be considered an operable condition. The operating surgeon must be aware of the various types and locations of paraduodenal hernias and look for them whenever operating for unexplained abdominal pain or obstruction. Contrary to the common assumptioh that paraduodenal hernias are rare congenital anomalies, we believe the rarity of this condition to be due to insufficient attention to the clinical picture and inadequate exploration of the paraduodenal hernia during laparotomy.

Choledochoduodenostomy in the treatment of benign biliary tract disease.

Recurrent surgical interventions on the biliary system for benign biliary tract diseases carry high morbidity and mortality. Choledochoduodenostomy creates a large and easily performed biliodigestive anastomosis enabling good drainage of the biliary system. Among 27 patients undergoing choledochoduodenostomy for benign biliary tract diseases, recurrent cholangitis occurred in only one patient, in whom a stenosed anastomosis was probably the culprit. The other patients have been free of abdominal complaints, cholangitis, or pancreatitis for follow-up periods of from six months to eight years. There was no operative mortality; morbidity was 45%, but hospital stay averaged only 14.7 days. The traditional objections to this procedure do not seem valid where choledochoduodenostomy is rightly indicated, the common bile duct is dilated, and a wide enough anastomosis is constructed. Our favorable results mark choledochoduodenostomy as a safe, simple, and effective procedure in the management of benign biliary tract disease, particularly in the high risk patient.

Studies on segmental pancreatic autotransplants in dogs.

Success with segmental pancreas transplants has been impaired by immunologic and technical considerations. Experiments were performed with autotransplants to avoid immunologic problems, allowing concentration on surgical techniques. Survival of splenic lobe pancreas autotransplants in pancreatectomized dogs was extended with relocation of the graft from the groin to the abdominal cavity and distal arteriovenous fistula to increase graft flow. Fibrosis of the graft occurred regardless of the method of duct treatment, latex (Neoprene) or Silastic injection or free intraperitoneal drainage. Hormonal responses in normoglycemic animals showed normal insulin levels (6 +/- 0.8 microU/mL) as compared with controls (5.4 +/- 0.9 microU/mL), while peak levels during arginine stimulation were higher in dogs with autotransplants (39.7 +/- 20 microU/mL) than in controls (15.1 +/- 1.9 microU/mL. Pancreatic polypeptide basal levels in animals with transplants were 42 +/- 2.2 pg/mL as compared with 256 +/- 28 pg/mL in controls, with no response to bombesin or protein meal stimulation. In this model, splenic lobe was capable of maintaining normoglycemia with avoidance of ketogenic amino acid patterns. Continuous fibrosis was the biggest threat to islet survival.

Carcinoma of colon after ureterocolic anastomosis: implantation on calyceal mucosa.

Two cases are reported of the development of mucoid adenocarcinoma of the colon in young patients, nineteen and thirty-four years after ureterocolic anastomosis for benign conditions. One patient showed implantation of the colonic neoplasm on the mucosa of an upper calyx in the obstructed kidney. Patients who have undergone ureterocolic anastomosis have a greatly increased risk of the development of large-bowel neoplasms. When suspected, radiologic examination of the colon using a water-soluble contrast material, together with rectosigmoidoscopy or colonoscopy, is essential. Because of the serious nature of this complication, it is suggested that the recent trend to return to the use of large bowel in urinary diversion may be hazardous, especially in the young patient with a benign disease.

Choledochoduodenostomy in the treatment of benign biliary tract disease.

During the 15 year period 1965 through 1979, sixty patients underwent choledochoduodenostomy for benign obstructive lesions of the biliary tract. Patients with traumatic and iatrogenic common duct strictures were excluded. Eighty-two percent of the patients were in the seventh to ninth decades of life. Twenty-seven patients (45 percent) had undergone a total of 40 previous biliary tract surgical interventions. Thirty-three patients (55 percent) in the older age group (average age 75 years) were subjected to choledochoduodenostomy as a primary procedure during the first surgical intervention on the biliary system. Cholangitis recurred in only one patient (in whom the sump syndrome was the culprit), while all other patients have been free of abdominal complaints, cholangitis and pancreatitis during follow-up of 1 to 15 years. There was no operative mortality; morbidity was 26 percent. Hospital stay averaged 15 days. These favorable results mark choledochoduodenostomy as a safe, simple and effective procedure in the treatment of benign biliary tract disease, particularly in aged and high risk patients.

Skin level permanent feeding gastrostomy.

Feeding gastrostomy can be troublesome, inconvenient and painful to the patient, especially if the catheter is redundant, thereby causing deformity of the opening ad leakage of gastric juice and food around the tube. A skin level permanent feeding gastrostomy was fashioned in four patients with neurologic disease. The mushroom catheter was introduced into the stomach, secured by a purse-string suture and fastened to the abdominal wall by a metal hub. The hub was fitted to a syringe by an adaptor for feeding purposes and was covered between meals. The device is simple to construct, safe, spill-proof and easily adopted by the patients.

A comparison of digital subtraction angiography and noninvasive testing in the diagnosis of cerebrovascular disease.

Among the 1,892 patients who underwent cerebrovascular digital subtraction angiography at our hospital over the past 18 months, there was a subgroup of 34 patients (65 carotid arteries) for whom noninvasive cerebrovascular test results and standard cerebral arteriograms were also available. These patients were reviewed retrospectively and the ability of both methods to detect hemodynamically significant lesions, defined as a greater than 50 percent reduction in the diameter of the carotid artery, was determined using the arteriograms as the "gold standard." Noninvasive cerebrovascular tests had a sensitivity of 81 percent, a specificity of 95 percent, a positive predictive value of 92 percent, a negative prediction value of 88 percent, and an overall accuracy of 89 percent. Digital subtraction angiography had a sensitivity of 84 percent, a specificity of 92 percent, a positive predictive value of 88 percent, a negative predictive value of 89 percent, and an overall accuracy of 89 percent. If the four cases of hemodynamically significant stenosis of the carotid siphon not detected by digital subtraction angiography had been considered as false-negatives, its sensitivity would have been reduced to 72 percent. In patients with hemispheric cerebral ischemia, we found noninvasive cerebrovascular tests neither necessary nor cost-effective. Digital subtraction angiography, on the other hand, often provided definitive diagnostic information in such patients if the intracranial circulation was well defined and the extracranial lesion corresponded to the patients' symptoms. Noninvasive cerebrovascular testing was the safest and most cost-effective technique for screening patients with asymptomatic bruits, atypical, nonhemispheric cerebral symptoms, and those who have undergone carotid endarterectomy. If the noninvasive cerebrovascular test result was positive or equivocal, digital subtraction angiography was performed to localize the responsible lesion and exclude carotid occlusion.

Surgical treatment of gastroesophageal reflux with esophageal stricture in infancy and childhood.

During the past 5 years, 26 infants and children with gastroesophageal reflux were operated on. The results have been highly satisfactory and unattended by serious complications or mortality. Barium fluoroscopy was the most reliable diagnostic method. The indications for operation were persistent vomiting with failure to thrive, recurrent aspiration pneumonia, gastrointestinal bleeding and peptic stricture of the esophagus, not relieved by medical treatment. The high incidence of peptic stricture of the esophagus (50 percent) may reflect delay in diagnosis and medical treatment, which is successful in 60 to 87 percent of the infants with gastroesophageal reflux. Surgical treatment consisted of Nissen fundoplication combined with gastrostomy in cases of esophageal stenosis where dilatations were indicated. Complications related to the operation were minimal. In a follow-up period of 9 months to 5 years, all patients had obtained relief of symptoms of reflux and had excellent nutritional status and normal growth.

Fever caused by leaking atherosclerotic abdominal aortic aneurysm.

Two cases of leaking atherosclerotic abdominal aortic aneurysm are presented. The leakage caused fever and leukocytosis, combined with signs of peritoneal irritation. Blood hemoglobin levels were reduced. Both patients were initially treated for sepsis but within hours the cause was identified; both died in the operating theater. The experience of others is reviewed and the mechanism of fever caused by leaking aneurysm is discussed.

The ileocecal segment: an anti-reflux conduit for hepatic portoenterostomy.

This paper describes an approach to prevent reflux and ascending cholangitis after hepatic portoenterostomy for biliary atresia. The method utilizes the terminal ileum and right colon as the conduit and a Nisson-type plication to the area of the ileocecal valve. It was used in one patient.

The simultaneous occurrence of paraduodenal and paracecal herniae presenting with volvulus of the intervening bowel.

A very rare coincidence of paraduodenal and paracecal hernia with volvulus of the intervening small intestine is reported. The unusual anatomical set up predising to volvulus of a large loop of small bowel has been described. Restoration of normal anatomy was made possible by the application of principles of treatment of internal herniae.

Use of clindamycin and gentamicin in pediatric colonic surgery.

The combination of clindamycin and gentamicin was used to treat 25 pediatric surgical patients. In 9 of the 11 patients with perforated appendicitis, B. fragilis was isolated from the peritoneal cavity. There was a rapid clinical response to treatment in all cases. No side effects were observed. Clindamycin and gentamicin seem to be the antibiotics of choice for such infections.

Semi-quantitative photoplethysmography in the diagnosis of lower extremity venous insufficiency.

A new standardization device has permitted calibration of the Photopulse Adaptor, thus, making venous photoplethysmography (PPG) a more accurate, semiquantitative technique. Using this device, we studied 10 normal volunteers and 151 extremities in 69 symptomatic patients We also developed a formula for calculating the slope of the venous recovery curve which took into consideration the degree of venous emptying as well as the duration of venous recovery. The PPG was "abnormal" if there was no measurable venous emptying despite effective calf contraction or if the calculated venous recovery rate (VRR) exceeded 2.0 mm/sec. VRR clearly separated normal extremities (1.28 mm/sec) from those in which venous reflux was present (3.34 mm/sec). If we had relied on measurement of venous recovery time (VRT) alone, 30% of hour normal volunteers and 52% of our symptomatic patients would have been misdiagnosed. We feel that these modifications have made PPG a more accurate technique less subject to the vagaries of arterial inflow, and thereby more valuable to the vascular surgeon in elucidating venous pathophysiology and following the results of his therapy.

CT guided periaortic fluid aspiration diagnosing aortic graft infection.

CT guided diagnostic aspiration was performed on a patient suspected of aortic graft infection. The positive aspiration prompted aggressive successful surgical intervention.

Preoperative dipyridamole-thallium scanning, selective coronary revascularization and long-term survival in patients with critical lower limb ischemia.

BACKGROUND: A large proportion of patients with critical limb ischemia have advanced, often asymptomatic coronary artery disease which is associated with increased perioperative risk and decreased long-term survival. METHODS: We evaluated retrospectively the short and long-term effect of routine dipyridamole-thallium cardiac scanning (DTS) and selective coronary revascularization in 113 consecutive patients who were scheduled for revascularization of the lower extremity. RESULTS: DTS was abnormal in 60 (53.1%) patients and demonstrated a moderate-severe reversible defect in 26 (23.0%) patients. On the basis of DTS and clinical evaluation 33 (29.2%) patients were referred for coronary catheterization. Of these, 9 underwent PTCA and 4 underwent coronary artery bypass, without complications. Surgical revascularization of the limbs was performed in all but two patients. Two (1.8%) patients died postoperatively, three (2.7%) sustained nonfatal postoperative myocardial infarctions. None of the patients who underwent preoperative coronary revascularization suffered a cardiac complication after the peripheral vascular operation. During mean follow-up of 31.7 months, 30 (28.0%) patients died. A moderate-severe reversible defect on DTS was the strongest predictor for shortened survival (Exp(b)=0.61, CI 95%=0.42-0.88; p=0.006). Patients who underwent preoperative coronary revascularization followed a survival curve approaching those without a reversible defect on DTS (mean survival 61+/-8 vs 63+/-4 months; NS) which was significantly better than those with such a defect who did not undergo coronary revascularization (mean survival 34+/-5 months; p=0.03). CONCLUSIONS: While the perioperative benefits of routine preoperative DTS screening in patients with critical limb ischemia, remain debatable, it provides an opportunity for identification and treatment of life-limiting coronary artery disease and improving survival.

Ultrasound-guided thrombin injection for the treatment of iatrogenic pseudoaneurysm of the femoral artery.

BACKGROUND: Pseudoaneurysm occurring after catheterization of the femoral artery is associated with significant morbidity. Percutaneous ultrasound-guided thrombin injection has recently emerged as a potential first-line therapy. OBJECTIVES: To evaluate the efficacy of this treatment in eight patients with iatrogenic femoral artery pseudoaneurysm. METHODS: After attempted treatment with external compression had failed, eight patients with iatrogenic femoral artery pseudoaneurysm were treated with thrombin injection. Treatment performed between 2 and 9 days following arterial puncture. The study group comprised seven males and one female ranging in age from 23 to 89 years (median 70). Seven had undergone cardiac catheterization with or without intervention, and five were receiving antiplatelet and/or anticoagulant drugs. Arterial pseudoaneurysm resulted from femoral vein catheterization in one patient. Using a sterile technique and real-time Doppler ultrasound guidance, a dilute solution of bovine thrombin (average dose 250 units, range 100-600), was slowly injected directly into the pseudoaneurysm until cessation of flow was seen. Patients were allowed to walk within 2 hours of the procedure and were followed up clinically and by color Doppler ultrasound during the admission. RESULTS: Cardiac catheterization had been inadvertently performed via the superficial or profunda femoris arteries in four of the eight patients. Thrombin injection was initially successful in all eight patients without complication. Thrombosis occurred immediately in every case. Early recanalization of pseudoaneurysm occurred in one patient despite repeat thrombin injection and attempted ultrasound-guided compression. He eventually required surgical repair. The final success rate was 87.5% (7/8). CONCLUSION: Faulty puncture technique is an important risk factor for the development of post-catheterization femoral artery pseudoaneurysm. Ultrasound-guided thrombin injection is a safe, rapid, well-tolerated, inexpensive and successful therapy. If initial external compression with a sandbag fails to result in thrombosis of the pseudoaneurysm then thrombin injection should be considered as first-line therapy. If unsuccessful, it does not preclude the use of alternative treatment modalities. Further study is necessary to assess the long-term effects of thrombin injection.