Measurement of high-energy (10-60 keV) x-ray spectral line widths with eV accuracy.

A high resolution crystal spectrometer utilizing a crystal in transmission geometry has been developed and experimentally optimized to measure the widths of emission lines in the 10-60 keV energy range with eV accuracy. The spectrometer achieves high spectral resolution by utilizing crystal planes with small lattice spacings (down to 2d = 0.099 nm), a large crystal bending radius and Rowland circle diameter (965 mm), and an image plate detector with high spatial resolution (60 µm in the case of the Fuji TR image plate). High resolution W L-shell and K-shell laboratory test spectra in the 10-60 keV range and Ho K-shell spectra near 47 keV recorded at the LLNL Titan laser facility are presented. The Ho K-shell spectra are the highest resolution hard x-ray spectra recorded from a solid target irradiated by a high-intensity laser.

New consistency tests for high-accuracy measurements of X-ray mass attenuation coefficients by the X-ray extended-range technique.

An extension of the X-ray extended-range technique is described for measuring X-ray mass attenuation coefficients by introducing absolute measurement of a number of foils - the multiple independent foil technique. Illustrating the technique with the results of measurements for gold in the 38-50 keV energy range, it is shown that its use enables selection of the most uniform and well defined of available foils, leading to more accurate measurements; it allows one to test the consistency of independently measured absolute values of the mass attenuation coefficient with those obtained by the thickness transfer method; and it tests the linearity of the response of the counter and counting chain throughout the range of X-ray intensities encountered in a given experiment. In light of the results for gold, the strategy to be ideally employed in measuring absolute X-ray mass attenuation coefficients, X-ray absorption fine structure and related quantities is discussed.

Nonoperative management of blunt splenic injury in adults 55 years and older: a twenty-year experience.

The nonoperative management of splenic injury secondary to blunt trauma in older patients remains controversial. We have reviewed our experience from January 1978 to December 1997 with selective nonoperative management of blunt splenic injury in adults 55 years and older. Criteria for nonoperative management included hemodynamic stability with any transient hypotension corrected using less than 2,000 cm3 crystalloid infusion, a negative abdominal physical examination ruling out associated injuries, and a blood transfusion requirement of no more than 2 units attributable to the splenic injury. During the study period, 18 patients over age 55 with radiographic confirmation of a splenic injury met the above criteria for nonoperative management. Their mean age was 72 years (range 56-86), and 13 of the 18 were female (72%). The mean Injury Severity Score was 15 (range 4-29), with the mechanism of injury equally divided between automobile crashes (9) and falls (9). During a similar time period, 15 patients 55 years or older with splenic injury composed an operative group; these patients did not differ with respect to age (mean 68 years), sex (60% female), or mechanism of injury. CT scans of 8 patients managed nonoperatively were available and graded using the American Association for the Surgery of Trauma classification, with a mean score of 2.3 (range 2-3). Eight of the 18 nonsurgical patients received blood transfusions. None of the 18 patients who met the criteria for nonoperative management "failed" the protocol, and none were taken to the operating room for abdominal exploration. Two patients (11%) died of associated thoracic injuries after lengthy hospital stays, one at 10 days and one at 24 days. We conclude from our data that nonoperative management of blunt splenic injury in patients age 55 years and older is indicated provided they are hemodynamically stable, do not require significant blood transfusion, and have no other associated abdominal injuries.

Human endothelial cell cultures from progenitor cells obtained by leukapheresis.

Although improved prosthetic graft patency with endothelial cell (EC) seeding has been shown in animal models, the clinical application of this technique requires a convenient source of ECs. We have evaluated EC cultures derived from the mononuclear cell (MNC) fraction obtained during large-volume leukapheresis and compared this with cultures grown from peripheral blood cells obtained by phlebotomy. Leukapheresis was performed in healthy adult volunteers (n = 7) using software designed to increase the percentage of MNCs harvested. Blood (40-293 mL) was drawn from a peripheral vein in healthy adult volunteers (n = 13), and the MNCs were obtained by differential centrifugation using a Lymphoprep gradient. Significantly more MNCs were obtained by leukapheresis than by phlebotomy. Each leukapheresis procedure yielded 12.5 to 23 mL, which contained 2.29 +/- 0.35 x 10(9) MNCs, compared with 2.16 +/- 0.50 x 10(8) MNCs, for each phlebotomy (P < 0.001). EC colonies developed in significantly more cultures from leukapheresis-derived MNCs (6 of 7) than phlebotomy-derived MNCs (4 of 13; P = 0.008). Leukapheresis-derived cells developed EC morphology at 15.5 +/- 2 days compared with 21 +/- 3.4 days for cells obtained by phlebotomy (P = not significant). EC were identified by positive factor VIII and vascular endothelial growth factor receptor immunostaining. Leukapheresis significantly increases the number of progenitor cells available for differentiation into EC compared with phlebotomy and avoids the need for any surgical procedure to harvest a peripheral vein as a direct source of ECs.

Isolation of endothelial cells and their progenitor cells from human peripheral blood.

PURPOSE: We have developed techniques to isolate endothelial cell (EC) progenitors from human peripheral and umbilical cord blood. METHODS: Human adult peripheral and umbilical cord blood monocytes were isolated by centrifugation, and progenitor cells were separated with the use of magnetic polystyrene beads that were coated with a monoclonal antibody specific for the CD34 cell-membrane antigen. Cells were propagated in selective media, and developing cultures were immunostained for CD31, CD34, factor VIII, and vascular endothelial growth factor cell receptors. ECs that developed were transfected with a gene for prourokinase and used to line ePTFE grafts, which were evaluated in vitro in a pulsatile flow system. RESULTS: Umbilical cord monocyte cultures demonstrated colonies that resembled ECs at approximately 2 weeks, with growth being best supported by EC growth media plus 20% calf serum with iron. Immunostaining of colonies was positive for CD31 and factor VIII. After 18 days in culture, CD34(+) cells from adult peripheral blood were noted, which had the typical cobblestone appearance of ECs and immunostained positively for CD31 and factor VIII-related antigens. Cultures of umbilical cord-derived cells and adult peripheral blood-derived cells developed complex line formations within 1 week in culture that stained positively for vascular endothelial growth factor receptor-2. Urokinase-transfected ECs were shown to overexpress urokinase. Prosthetic grafts lined with transfected cells showed 87.33% +/- 4.97% cell adherence after 2 hours in a pulsatile flow system at clinically relevant shear stress. CONCLUSION: We conclude that endothelial progenitor cells can be isolated from human adult peripheral and umbilical cord blood and developed into EC cultures as a source of cells for vascular graft seeding and gene therapy.

Octreotide in the treatment of thoracic duct injuries.

Anecdotal reports support the use of octreotide in the treatment of traumatic thoracic duct injuries and chylothorax, but no prospective studies have proved its efficacy. We evaluated the effects of octreotide in treating thoracic duct transection in a canine model. Eight mongrel dogs (27.8+/-5.1 kg) were fed one pint of 10.5 per cent milkfat 2 hours before operation. Through a left supraclavicular neck incision, the thoracic duct was identified and transected, producing free flow of chyle. A quarter-inch drain was tunneled subcutaneously from the wound and attached to closed suction. After wound closure dogs were randomized to a control group (n = 4) receiving sham injections of saline subcutaneously three times per day, or a treatment group (n = 4) given 3 microg/kg octreotide three times per day. Postoperatively all dogs were fed a standard low-fat (5-7%) crude fat diet. Drain output was measured each day, and on odd-numbered postoperative days the drainage was analyzed for cholesterol, triglycerides, albumin, and total protein. Fistula closure was defined as drainage <10 ml/24-hour period. Treated dogs achieved fistula closure significantly faster than controls: 3.5+/-1.3 days versus 7.8+/-1.0 days (P = 0.0037). Whereas equivalent amounts of drainage occurred on the day of surgery and on postoperative day one in both groups, by postoperative day 2 the treatment group had significantly less drainage over 24 hours: 63+/-69 ml versus 195+/-79 ml (P = 0.046); this significant difference persisted through postoperative day 5 when drainage began to decrease in the control group. No significant differences between groups were seen in levels of cholesterol, triglycerides, albumin, or protein in the drainage at any time point. We conclude that octreotide is effective in treating thoracic duct injury, leading to an early decrease in drainage and early fistula closure. The mechanism for this effect remains to be clarified.

The effect of graded compression elastic stockings on the lower leg venous system during daily activity.

PURPOSE: We evaluated the effects of wearing 20 to 30 mm Hg gradient thigh-length stockings during daily activity on the lower leg venous system. METHODS: Twenty-one healthy women volunteers, aged 39 +/- 12 years, were examined. One subject was clinical class 4, one was class 2, two were class 1, and the remainder were class 0. The diameter of the posterior tibial, peroneal, and greater saphenous veins were measured at midcalf by means of bilateral duplex ultrasound scanning; calf circumference was measured at the same level. In addition, the number and caliber of all detectable medial calf perforating veins were recorded. Each subject was examined on two separate days, one while wearing the gradient stockings and one not wearing them. Baseline measurements were made on each day before the subjects began their workday, with follow-up measurements made after approximately 4.5 hours of normal activity. RESULTS: Calf circumference increased an average of 23.8 +/- 10.1 mm without stockings (P <.001) and decreased by 5.2 +/- 7.0 mm when wearing stockings (P =.003). The number of detected perforating veins increased without stockings by 1.8 +/- 2.0 at the follow-up examination (P =.002); with stockings, the change was 0.4 +/- 1.2 (P = NS). CONCLUSION: Graded compression elastic stockings help preserve lower leg venous caliber and tone throughout the deep, superficial, and perforating venous systems during normal ambulatory activity, and this may, in part, explain their beneficial effects.

Prosecution and conviction of the injured intoxicated driver.

BACKGROUND: Previous studies have reported low conviction rates for drunk drivers injured in motor vehicle crashes and transported to the hospital. The purpose of this study was to evaluate this rate during a recent period and to investigate the variables that predict alcohol-related convictions for injured drunk drivers admitted to our hospital. METHODS: A retrospective review of medical records from January 1991 through May 1997 identified 71 patients who were legally intoxicated drivers injured in motor vehicle crashes. Court records, police reports, and driving records were also obtained. RESULTS: Overall, 51% of the drunk drivers were convicted of alcohol-related offenses and 32% escaped without any conviction. Blood alcohol level and a police officer's estimation of whether the driver had been drinking were significant predictors of an alcohol-related conviction. Age, Injury Severity Score, a police officer's estimation of injury, and the number of people or cars involved in the crash were not significantly associated with legal outcome. CONCLUSION: Although this study shows an important increase in alcohol-related conviction rates, responsibility for further progress will depend on the medical community, law enforcement agencies, and the judicial system working together.

Three-dimensional vascular imaging using Doppler ultrasound.

BACKGROUND: We have evaluated the efficacy of using three-dimensional reconstruction of amplitude Doppler imaging data to quantitatively assess carotid artery bifurcation stenoses. METHODS: Sixty-four consecutive frames of amplitude (power) Doppler images are stored to be reassembled into a three-dimensional image representing the patent lumen. These images can then be rotated by any angle necessary to clearly view the vascular anatomy and to make quantitative ultrasound caliper measurements of the stenotic lumen and normal vessel caliber. RESULTS: Three-dimensional Doppler images accurately classified 53 of 61 vessels (87%) into categories of stenosis compared with angiography. All stenoses with >60% diameter reduction were detected and classified as such, for a sensitivity of 100%. CONCLUSIONS: Three-dimensional vascular imaging based on amplitude (power) Doppler data provides an accurate noninvasive technique for quantitative diagnosis of carotid bifurcation atherosclerotic disease, with selectable viewing projections that eliminate vessel overlap and other artifacts, and complements the hemodynamic data already available with two-dimensional duplex ultrasound.

Improved adherence of genetically modified endothelial cells to small-diameter expanded polytetrafluoroethylene grafts in a canine model.

PURPOSE: A significant limitation to using genetically modified endothelial cells (ECs) to seed prosthetic grafts before implantation has been poor cell adherence to the graft lumen. Methodologic changes to improve cell adherence were evaluated in a canine carotid interposition graft model using 4 mm interior diameter expanded polytetrafluoroethylene. METHODS: ECs harvested from external jugular veins were grown in culture, with 80% of the cells from each culture transduced by incubation with an LXSN-type retroviral vector carrying a gene for human prourokinase and a neomycin resistance gene for selection in antibiotic G418. Control grafts had passive luminal coating with fibronectin and were seeded with transduced ECs immediately after G418 selection; these grafts were incubated for 2 days before implantation. Experimental grafts had fibronectin forcefully squeezed through the interstices and were seeded with ECs that had recovered in culture for 5 days after G418 selection; these grafts were incubated for 4 days before implantation. For each control (n = 9) and experimental (n = 12) graft, a graft prepared in the same fashion but seeded with the remaining autologous nontransduced cells was placed in the contralateral carotid artery. Grafts were explanted after 30 days and were evaluated for patency, thrombus-free surface area, and cell-free surface area. RESULTS: No significant differences in patency rates were seen between any groups. The thrombus-free surface area was improved for experimental grafts (90%) compared with control grafts (76%), but this improvement did not achieve statistical significance. The cell-free surface area for transduced cells on experimental grafts was 65% compared with 96% for control grafts (p = 0.021) and was comparable with that for nontransduced cells on both control grafts (62%) and experimental grafts (51%; p = 0.201). CONCLUSIONS: Adherence of genetically modified endothelial cells to small-diameter expanded polytetrafluoroethylene grafts in an in vivo physiologic flow model is significantly improved when cells have a more prolonged recovery from G418 selection, when the graft lumen is more uniformly coated with fibronectin before EC seeding, and when seeded grafts are left longer in culture before implantation to develop cell lining stability. The short-term patency rate of these seeded grafts is not affected by increased cell retention; long-term graft patency data and luminal healing require further evaluation.

A 4-year outcome-based retrospective study of wound healing and limb salvage in patients with chronic wounds.

This multicenter, retrospective study evaluated the wound healing and limb salvage outcomes over a 4-year period in 3,830 patients in 39 hospital-affiliated Wound Care Centers. These centers provide comprehensive outpatient wound care for chronic, nonhealing wounds. Two distinct outcomes were identified: (1) wound healing with comprehensive wound care (CWC) alone, and (2) wound healing with comprehensive wound care plus platelet releasate (CWC+PR). Data were analyzed with respect to healing and limb salvage in two groups: 1,019 patients who received CWC and 2,811 patients who received CWC+PR. Analysis of the standardized, customized database showed that overall healing rates were higher (p < .00001) and amputation rates were lower (p = .00005) in the CWC+PR group than in the CWC group. In addition, when healing rates were analyzed according to underlying condition, patients with all underlying conditions except autoimmune disorders showed higher healing rates in the CWC+PR group than in the CWC group. This study showed that patients treated with comprehensive wound care plus topical use of autologous platelet releasate had significantly higher rates of wound healing and increased limb salvage for most wounds than those treated with comprehensive wound care alone.

Serial duplex ultrasound examinations for deep vein thrombosis in patients with suspected pulmonary embolism.

PURPOSE: We have prospectively evaluated the need for serial venous duplex ultrasound examinations in an inpatient population with an initially normal study result. METHODS: Patients were selected for study on the basis of clinical suspicion of pulmonary embolism and possible lower extremity deep vein thrombosis, a comorbid condition contributing to a nondiagnostic ventilation/perfusion lung scan, and an initially normal bilateral venous duplex ultrasound examination that included complete evaluation of the femoropopliteal system and the deep calf veins. Repeat duplex examinations were done during the same hospital admission between 5 and 14 days after the initial study. RESULTS: Ninety-four patients with an initially normal duplex ultrasound examination result had repeat studies done at an average of 7.9 +/- 2.6 days. Ninety-two examination results remained normal bilaterally. Two patients had isolated intramuscular calf vein deep vein thrombosis: one in the gastrocnemius system of both calves with associated calf tenderness at 11-day follow-up and one in a mid-calf soleal vein without associated symptoms at 10 days. No patients had any evidence of deep vein thrombosis in the femoropopliteal or tibioperoneal venous systems. CONCLUSIONS: Serial follow-up duplex ultrasound evaluation is unnecessary after an initially complete, normal study in patients with symptoms who have suspected pulmonary embolism and nondiagnostic ventilation-perfusion lung scans.

Progression of superficial venous thrombosis to deep vein thrombosis.

PURPOSE: We have evaluated the progression of isolated superficial venous thrombosis to deep vein thrombosis in patients with no initial deep venous involvement. METHODS: Patients with thrombosis isolated to the superficial veins with no evidence of deep venous involvement by duplex ultrasound examination were evaluated by follow-up duplex ultrasonography to determine the incidence of disease progression into the deep veins of the lower extremities. Initial and follow-up duplex scans evaluated the femoropopliteal and deep calf veins in their entirety; follow-up studies were done at an average of 6.3 days, ranging from 2 to 10 days. RESULTS: From January 1992 to January 1996, 263 patients were identified with isolated superficial venous thrombosis. Thirty (11%) patients had documented progression to deep venous involvement. The most common site of deep vein involvement was progression of disease from the greater saphenous vein in the thigh into the common femoral vein (21 patients, 70%), with 18 of these extensions noted to be nonocclusive and 12 having a free-floating component. Three patients had extended above-knee saphenous vein thrombi through thigh perforators to occlude the femoral vein in the thigh, three patients had extended below-knee saphenous disease into the popliteal vein, and three patients had extended below-knee thrombi into the tibioperoneal veins with calf perforators. At the time of the follow-up examination all 30 patients were being treated without anticoagulation. CONCLUSIONS: Proximal saphenous vein thrombosis should be treated with anticoagulation or at least followed by serial duplex ultrasound evaluation so that definitive therapy may be initiated, if progression is noted. More distal superficial venous thrombosis should be carefully followed clinically and repeat duplex ultrasound scans performed, if progression is noted or patient symptoms worsen.

Coronary artery bypass and valve replacement in octogenarians.

A total of 325 patients, aged 80 to 92 (mean 82), underwent cardiac operations with cardiopulmonary bypass over a 4-year period (1991-1995). Hypothermia (22 degrees C) and hyperkalemic cardioplegia were used in each. Coronary bypass procedures only (Group I) were performed in 255 patients with 22 early deaths (8.6%), and the average number of grafts was 3.7 per patient. Single or double valve replacement, with coronary bypass (Group II) was performed in 46 patients, with six early deaths (13%). Single or double valve replacement, without coronary bypass (Group III) was performed in 24 patients, with two early deaths (8.3%). Total hospital mortality was 30 deaths in 325 patients (9.2%). Fifty-six procedures (22%) from Group I and four (9%) from Group II were performed as emergencies, and all operations in Group III were elective. Seventy-two patients (27%) from Group I, 18 patients (39%) from Group II, and nine patients (37%) from Group III had major complications including renal failure, cerebrovascular accident, myocardial infarction, postoperative hemorrhage, sepsis, and ventilatory dependency. Mean hospital stay was 10.5 days for Group I, 13.3 days for Group II, and 15.2 days for Group III, with an overall mean of 13 days (range, 6-52) days. Higher mortality was related to a cardiac index <1.8, cardiogenic shock, emergency operation, creatinine >2.0, and morbid obesity. Mean left ventricular ejection fractions were 0.51 for Group I, 0.45 for Group II, and 0.49 for Group III. Preoperative risk factors associated with a higher mortality included hypertension, smoking, diabetes, and pulmonary hypertension. Two hundred seventy-two of the 299 operative survivors were followed for a mean of 18 (range, 3-52) months. The actuarial survival of octogenarians is 92 per cent, 80 per cent, and 65 per cent at 1, 3, and 5 years, respectively, and of the patients surviving operation it was 85 per cent, 70 per cent, and 55 per cent at 1, 3, and 5 years, respectively. At postoperative follow up, 80 per cent of the survivors reported an active functional status, and there was a low incidence of cardiac-related deaths.

Appropriate indications for venous duplex ultrasonographic examinations.

BACKGROUND: Because of the rapid growth in requests for lower extremity venous duplex ultrasonographic examinations, we have evaluated test results to determine the appropriate indications for testing and whether there is overuse of this technique. METHODS: We reviewed the records of all patients who had duplex ultrasonogram during an 18-month period to rule out deep vein thrombosis (DVT). Test outcome was evaluated with data on the age, gender, outpatient or inpatient status, duration of symptoms, physical findings, and risk factors of the patients. RESULTS: We reviewed 3474 examinations; 1265 outpatients and 1231 inpatients were evaluated to rule out DVT, and 978 patients were evaluated to rule out a source of pulmonary embolism. More outpatients were female, and they tended to be younger; outpatients also had more acute femoropopliteal DVT. The presence of sudden onset of unilateral swelling was a strong predictor of acute DVT in all three groups: 52% of such patients were found to have DVT. Mild unilateral symptoms with a coexistent risk factor was associated with a 10% to 20% prevalence of acute DVT. Chronic unilateral swelling was associated with acute DVT only with a coexistent risk factor and only in 1% of such patients. Bilateral swelling was only associated with acute DVT in the inpatient population, with 17% of studies having positive results. If calf tenderness was the only symptom with no associated risk factors, seven (1.6%) of 415 patients had acute DVT and six of these were tibioperoneal. No patients with cellulitis or isolated joint pain had acute DVT. With clinically suspected pulmonary embolism in patients without associated symptoms or risk factors, 7 (1.5%) of 447 studies showed tibioperoneal disease with no acute femoropopliteal disease. CONCLUSIONS: The physical examination and clinical history of the patient remain important indicators of the presence (or absence) of lower extremity DVT and can guide the appropriate use of duplex ultrasonography for the diagnosis.

Spermatic cord hematoma: case report and literature review.

Spermatic cord hematoma is a rare diagnosis. The etiology may be idiopathic, traumatic, secondary to anticoagulation therapy, or as an extension of a retroperitoneal hemorrhage. It has been misdiagnosed as an incarcerated inguinal hernia, a testicular torsion, or a tumor. A review of the English literature is presented. An additional case is presented here as a complication of anticoagulation therapy after aortic valve replacement. Risk factors for a spermatic cord hematoma may warrant an ultrasound examination.

Urokinase expression in transduced endothelial cells.

Increased thromboresistance through the release of lytic agents by endothelial cells may improve the patency of endothelial lined prosthetic grafts. We have evaluated the expression of urokinase from cells transduced with a retrovirus containing the gene for a human preprourokinase. Endothelial cells were enzymatically harvested from canine external jugular vein in nine animals and grown to confluence in culture. One-third of these cells served as controls, and the remaining two-thirds were transduced via incubation with an LXSN-type retroviral vector carrying the urokinase gene and a neomycin resistance gene. Successfully transduced cells were selected by incubation with 400 micrograms/mL G418 and pure cultures grown to confluence. Supernatants from confluent control and experimental cell cultures after 48 hours in defined, serum-free medium were assayed for human urokinase concentration and overall enzyme activity. ELISA quantitation of concentration using mouse antihuman urokinase antibody showed 0.15 +/- 0.11 ng/mL/hr/10(6) cells in the transduced cell supernatant; no measurable concentration was found in the control cells. (P < 0.01) Overall (human plus canine) enzyme activity of urokinase was determined using an indirect spectrophotometric assay based on plasminogen activation (ploug U/mL). Transduced cells showed activities of 0.12 at 10 days and 0.45 at confluence; control cell activity was 0.0 and 0.15, respectively. (P < 0.05) These data show that endothelial cells can be transduced with a urokinase expressing gene that increases the release of this thrombolytic agent. Lining small diameter prosthetic grafts with these cells may improve their thromboresistance and long-term patency.

Carotid endarterectomy based on preoperative duplex ultrasound.

Recent studies have suggested that carotid endarterectomy can be performed safely based solely on the noninvasive duplex ultrasound evaluation in selected patients. We have prospectively evaluated 60 consecutive patients who underwent 65 carotid endarterectomies, 48 patients without preoperative angiography and 12 with angiography. Forty-two patients were operated on for symptomatic disease, and 23 procedures were done for critical, asymptomatic stenoses. Long term followup consisted of physical examination and serial duplex scans every 3-6 months postoperatively over a mean followup period of 2.4 years. Clinical management indicated by duplex ultrasound was altered in only one of the 12 patients who had preoperative angiography, a change in the timing of the endarterectomy in a symptomatic patient with an ulcerated lesion seen at angiography. At operation the severity of disease predicted by duplex ultrasound was confirmed in all cases (100 per cent sensitivity), including one > 80% diameter stenosis interpreted by angiography as occluded; no unsuspected anatomic anomalies were found at surgery. The duplex scan also correlated well with intraoperative findings of surface ulceration and gross intraplaque hemorrhage. There was one intraoperative stroke with good recovery in a patient with preoperative angiography; and there were no deaths, for a combined morbidity and mortality of 1.6 per cent. During long term followup, 97 per cent of patients have remained symptom-free. We conclude that clinical assessment with a preoperative duplex ultrasound scan of good technical quality and interpreted in collaboration with the vascular surgeon provides appropriate information on which to base carotid endarterectomy and allows a safe alternative to the routine use of preoperative angiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Closed drainage versus open packing of infected pancreatic necrosis.

Infected pancreatic necrosis is the most lethal form of pancreatic infections. We have compared our results of open packing and closed catheter drainage after surgical debridement in 20 patients between 1978 and 1993. There were 18 men and 2 women, ages 18 to 72 (mean 54 years). Pancreatitis was attributed to alcohol in eight patients, gallstones in four, surgery in four, hyperlipidemia in one, and was unknown in one. The most common infectious organisms were Strep. viridans, E. coli, Staph aureus, and Candida albicans. Surgical debridement and closed catheter drainage without lavage was the initial treatment in nine patients. Seven of 9 (78%) required reoperation for recurrent abscess and necrosis. Procedure related morbidity was 70 per cent and overall mortality was 44 per cent. Sepsis was the cause of death in three patients and multi-system organ failure in one patient. Surgical debridement and open packing was performed in 11 patients. Each patient had scheduled reoperations for repeat debridement and packing an average of 10 times over 21 days. Procedure-related morbidity was 73 per cent and overall mortality was 18 per cent. One patient died of cardiac failure and one of multisystem organ failure. Retroperitoneal hemorrhage and recurrent abscesses were more frequent after closed drainage, whereas gastric fistula and incisional hernia were more frequent after open packing. Ventilator dependence, pancreatic and intestinal fistula, and organ failure occurred at the same rate. In conclusion, surgical debridement and open packing, with planned redebridement and packing, is more effective in controlling the septic process than is closed catheter drainage of infected pancreatic necrosis.

The relationship of cardiac and neurological complications to blood pressure changes following carotid endarterectomy.

This study was undertaken to study serial blood pressure changes following carotid endarterectomy (CE) and to analyze their relationship to neurological and cardiac complications. Over a 41 month period, 330 carotid endarterectomies (CE) were studied prospectively. Elevation of blood pressure developed in 214 of 330 (64%) patients undergoing CE. Four patients in the CE group developed perioperative myocardial infarction. None of these patients had hypertension following CE. Eleven patients (3.3%) developed new neurological deficits; 10 of these patients had perioperative hypertension (P = 0.041). Hypertension following carotid endarterectomy increased the likelihood of neurological deficit, but not a myocardial infarction.