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J F Buell

Publications and source records attributed to J F Buell.

At least 37 records · Page 2Linked to original sources

Global cardiovascular risk under early corticosteroid cessation decreases progressively in the first year following renal transplantation.

UNLABELLED: A primary reason to eliminate corticosteroids from immunosuppressive regimens in solid organ transplant recipients is improved cardiovascular risk profiles. Although a number of studies have documented that corticosteroid withdrawal (CSWD) regimens reduce hypertension, hyperlipidemia, diabetes, and weight gain, global assessments of cardiovascular risk under CSWD have not been reported. The purpose of this study was to document cardiovascular risk under CSWD using a global risk assessment by Framingham risk assessment. METHODS: Framingham global cardiovascular risk assessments were performed at baseline and 3, 6, and 12 months posttransplant on patients enrolled in prospective, IRB-approved early (<7 days of corticosteroids) CSWD trials. Framingham score was based on age, sex, presence of diabetes, HDL and total cholesterol, and systolic blood pressure. All patients were nonsmokers. Left ventricular hypertrophy assessment by EKG criteria was not available at all time points and therefore were not included. RESULTS: One hundred eighty-three patients were included in the analysis. Fourteen percent of patients had evidence of coronary heart disease (prior MI, CABG, PTCA, or significant cardiovascular disease as evidenced by angiography) prior to transplant. Complete information was available for 160 patients at baseline, 132 at 1, 3, and 6 months, and 93 at 12 months posttransplant. Mean 10-year risk (expressed as percent) for developing coronary heart disease decreased over time: 8.03 at baseline, 8.31 at 3 months, 7.40 at 6 months, and 7.20 at 12 months, indicating that global cardiovascular risk fell at 1 year posttransplant by about 10% in renal transplant recipients undergoing early CSWD. CONCLUSIONS: Estimation of cardiovascular risk by Framingham risk factor assessment allows incorporation of several cardiovascular risk factors into a single estimate, thereby accounting for differential effects of each individual factor on global cardiovascular risk. This experience indicates that global cardiovascular risk decreases by approximately 10% at 1 year posttransplant in renal transplant recipients who undergo early corticosteroid withdrawal (CSWD).

Adrenal Cortex Hormones↗

Epidemiology and clinical consequences of vancomycin-resistant enterococci in liver transplant patients.

BACKGROUND: Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplant patients. To guide control efforts, we conducted an epidemiological study of the frequency, source, and modes of transmission of VRE at our center. METHODS: During September 1998 through August 1999, we obtained weekly surveillance cultures from consenting liver transplant patients and surfaces in their rooms. Pooled handwash specimens from personnel also were obtained. Specimens were processed on selective media to detect VRE, and isolates were typed by pulsed field gel electrophoresis. Information was collected from patient records concerning in-hospital treatment and clinical course. RESULTS: Serial cultures were obtained during 33 admissions of 29 patients. VRE were detected in initial specimens from 6 admissions, and nosocomial acquisition of VRE occurred in 12 (44%) of the remaining 27 admissions. Seven different strain types of VRE were detected. The initial site of acquisition was stool in all cases; bile became culture-positive in only two patients. Overall, 16 (55%) of the 29 patients became colonized, usually after transplantation. VRE were detected in environmental cultures during 10 admissions and in 2 of 21 pooled handwashes. No statistically significant differences in clinical status or treatment were found when colonized patients were compared to noncolonized controls. The only VRE infection resulted from a choledochojejunostomy anastomotic leak. CONCLUSION: Alimentary tract colonization by VRE occurred commonly in liver transplant patients, probably by cross-transmission. The clinical consequences were modest in the patients studied, but colonized transplant patients provide a substantial reservoir for continued VRE transmission in hospitals.

Adult↗

Emergent lung retransplantation after discovery of two primary malignancies in the donor.

A 50-year-old woman underwent single lung transplantation for advanced chronic obstructive pulmonary disease. Shortly after the procedure, it was discovered that the donor suffered from both a renal cell carcinoma and a spindle-cell sarcoma of the ascending aorta, which had metastasized to the spleen. The patient was emergently listed for a retransplantation and underwent bilateral lung transplantation after a new donor became available 4 days after the initial transplantation procedure. After 24 months, the patient is without evidence of malignancy. This case illustrates the role of immediate retransplantation for patients who have inadvertently received thoracic organs from donors harboring occult malignancies.

Adult↗

Is any method of vascular control superior in hepatic resection of metastatic cancers? Longmire clamping, pringle maneuver, and total vascular isolation.

HYPOTHESIS: Although control of the hepatic vascular pedicle is commonly used during hepatic resection, the optimal method of vascular control continues to be debated. The utility of total or selective vascular isolation, pedicle inflow occlusion, or the absence of vascular isolation during minor and major hepatectomy needs to be examined. DESIGN: Retrospective review of hepatic resections performed for either isolated colorectal or noncolorectal hepatic metastases. SETTING: The University of Chicago Hospitals, Chicago, Ill, a tertiary-care referral center. PATIENTS: One hundred forty-one patients who underwent hepatic resection for isolated metastatic liver disease were identified through The University of Chicago Hospitals Tumor Registry. MAIN OUTCOME MEASURES: Intraoperative parameters, perioperative morbidity and mortality, and tumor recurrence. RESULTS: Four groups were compared with alternative methods of vascular management, including total vascular isolation, Longmire clamping, Pringle maneuver, or no vascular control. Tumor number and size were not significantly different between groups. Blood loss and transfusion requirements tended to be higher in the total vascular isolation group and were significantly higher compared with the Pringle group (P =.06) and the no vascular control group (P =.04), but this also correlated with a higher incidence of complexity of surgical resection. The highest incidence of postoperative complications occurred in the total vascular isolation group (P<.05). With similar permanent pathologic margins, the rates of intrahepatic recurrence were similar among all groups, with the no vascular control group having the lowest recurrence rate. CONCLUSIONS: All methods of vascular control appeared equivalent with respect to limiting blood loss and transfusion requirements while providing adequate surgical margins. The highest rates of blood requirements and complications were noted in the total vascular isolation group, which corresponded to the highest incidence of complex resections. The Longmire clamp group incurred the lowest incidence of complications and resulted in identical surgical margins. The application of vascular control is beneficial to surgeons during hepatic resection, but the method of control should be selected based on the location and complexity of resection required and preference of the individual surgeon.

Aged↗

Transmission of donor cancer into cardiothoracic transplant recipients.

BACKGROUND: The demand for transplantable organs exceeds donor supply. Patients with central nervous system (CNS) or other tumors are controversial donors, and the donor cancer transmission rates in cardiothoracic transplant recipients have not been determined. The Israel Penn International Transplant Tumor Registry (IPITTR) was queried to define the risk of donor cancer transmission in cardiothoracic transplant recipients. METHODS: All heart, lung, or heart-lung recipients of organs from donors with a history of malignancy were reviewed. Donor and recipient demographics, histologic findings, and recurrence were reviewed. RESULTS: Twenty-two patients received 17 hearts, 3 lungs, and 2 heart-lung transplants from donors with known CNS or other malignancies. No malignancy transmissions were noted with astrocytomas (n = 3) or glioblastomas (n = 1), except a medulloblastoma that recurred at 6 months. The transmission rate for CNS tumors was 17% (1 of 6), and 1- and 3-year survivals were 67% and 50%, respectively. The most common non-CNS donor cancer was renal cell carcinoma (n = 5). Two renal cell cancer transmissions occurred, both when vascular extension was present. The most aggressive tumor transmission was choriocarcinoma (n = 2) and melanoma (n = 2). Two of 3 choriocarcinomas metastasized with 67% mortality, and both melanomas were transmitted and resulted in death. Other donor cancers included angiosarcoma (n = 2), cervical (n = 1), lung (n = 1), prostate (n = 1), and a liver adenocarcinoma. The transmission rate for all non-CNS groups was 56% (9 of 16) with a 2-year survival of 40%. CONCLUSIONS: The IPITTR experience indicates that tumor transmission is high (10 of 22, 45%) in cardiothoracic transplant recipients. Similar to intra-abdominal organ recipients in the IPITTR, (1) renal cell carcinomas without capsular invasion appear safe with no transmission, (2) vascular invasion in renal cell carcinoma appears to result in early tumor transmission, and (3) melanoma and choriocarcinoma have high rates of transmission with early and almost universal death.

Brain Neoplasms↗

Are concerns over right laparoscopic donor nephrectomy unwarranted?

OBJECTIVE: To examine the ability of several large, experienced transplantation centers to perform right-sided laparoscopic donor nephrectomy safely with equivalent long-term renal allograft function. SUMMARY BACKGROUND DATA: Early reports noted a higher incidence of renal vein thrombosis and eventual graft loss. However, exclusion of right-sided donors would deprive a significant proportion of donors a laparoscopically harvested graft. METHODS: A retrospective review was performed among 97 patients from seven centers performing right-sided laparoscopic donor nephrectomy. Surgical and postoperative demographic factors were evaluated. Complications were identified and long-term renal allograft function was compared with historical left-sided laparoscopic donor nephrectomy cohorts. RESULTS: Right laparoscopic donor nephrectomy was performed for varying reasons, including multiple left renal arteries or veins, smaller right kidney, or cystic right renal mass. Mean surgical time was 235.0 +/- 66.7 minutes, with a mean blood loss of 139 +/- 165.8 mL. Conversion was required in three patients secondary to bleeding or anatomical anomalies. Mean warm ischemic time was limited at 238 +/- 112 seconds. Return to diet was achieved on average after 7.5 +/- 2.3 hours, with mean discharge at 54.6 +/- 22.8 hours. Two grafts were lost during the early experience of these centers to renal vein thrombosis. Both surgical and postoperative complications were limited, with few long-term adverse effects. Mean serum creatinine levels were higher than open and left laparoscopic donor nephrectomy on postoperative day 1, but at all remaining intervals the right laparoscopic donors had equivalent creatinine values. CONCLUSIONS: These results confirm that right laparoscopic donor nephrectomy provides similar patient benefits, including early return to diet and discharge. Long-term creatinine values were no higher than in traditional open donor or left laparoscopic donor cohorts. These results establish that early concerns about high thrombosis rates are not supported by a multiinstitutional review of laparoscopic right donor nephrectomies.

Adolescent↗

Surgical management of benign tumors of the liver.

INTRODUCTION: Benign tumors of the liver are increasingly being diagnosed and continue to represent a management challenge. These lesions constitute a substantial component of hepatic neoplasms evaluated and resected at a tertiary referral center. We reviewed our experience with resection of benign liver lesions to clarify the safety and effectiveness of this treatment. METHODS: Between January 1996 and January 2000, 28 patients with benign hepatic lesions were identified from a cohort of 140 hepatic resection patients. Demographic characteristics, operative management, morbidity, mortality and follow-up were retrospectively analyzed. RESULTS: The mean age in our patients was 35 +/- 14, with 24/28 (86%) patients being female. Seven of the 24 woman (29%) at presentation were either pregnant or immediate postpartum. A history of OCP use was noted in 14/24 (58%) female patients. The most common presenting symptom was abdominal pain in 12/28 (43%). Resection for an undiagnosed mass occurred in 11/28 (39%) patients. The distribution of pathology was hemangioma 10/28 (35.7%), adenoma 8/28 (28.6%), hepatic cyst 5/28 (17.9%), hamartoma 2/28 (7.1%), and FNH 3/28 (10.7%). Average size of the tumor was 7.4 +/- 3.9 (range 2.5-15 cm) with a mean of 1.4 +/- 0.8 lesions (range 1-3) per patient. Tumors were evenly distributed between the right and left side while eight patients (29%) had bilobar tumors. Enucleation rather than anatomic resection was performed in 18/28 (64%) patients, with a mean blood loss of 457 +/- 532 cc (range 50-2200 cc). Blood transfusion was required in only 3/28 (10%) patients, while total vascular isolation was used in only a single patient undergoing an extended left hepatectomy. Mean length of stay was 6.8 +/- 3.2 d (range 3-14 d). Three complications (10.7%) were encountered: pulmonary embolus, ileus and non-operative bile leak. There were no mortalities in this series. Recurrence of tumor occurred in only one patient with a giant hepatic cyst managed laparoscopically. CONCLUSIONS: In our institution, the management of clinically relevant benign tumors of the liver comprises a significant proportion of our resectional practice (20%). Our data suggests that both enucleation and anatomically based resections can be performed safely with minimal blood loss and transfusion requirements. Resection of symptomatic lesions was highly effective in treating abdominal pain due to these benign tumors. We advocate resection of non-resolving hepatic adenomas, symptomatic lesions, or when malignancy cannot be excluded.

Adenoma↗

Initial presentation with stage IV colorectal cancer: how aggressive should we be?

HYPOTHESIS: The appropriate surgical treatment of patients with colorectal cancer who are found on initial presentation to have stage IV disease is controversial. With presumed limited life expectancy, the role of primary colon or rectal resection has been questioned, as has the utility of synchronous hepatic resection. DESIGN: A retrospective chart review. SETTING: The University of Chicago Hospitals, Chicago, Ill, a tertiary-care referral center. PATIENTS: One hundred twenty patients were identified through The University of Chicago Hospitals Tumor Registry whose initial presentation showed stage IV colorectal cancer and who underwent laparotomy. MAIN OUTCOME MEASURES: The primary end points of the study were perioperative morbidity and mortality and overall survival. RESULTS: Median survival and 5-year survival were 14.4 months and 10%, respectively. Survival was greater for patients younger than 65 years than for those who were aged 65 years or older (18.3 vs 9.8 months; P = .007). Carcinomatosis was associated with significantly decreased survival when compared with less extensive stage IV disease (6.7 vs 18.1 months; P<.001). Patients who underwent any form of resection of hepatic metastases achieved a survival advantage over those with unresectable liver lesions (median survival, 29.6 vs 10.2 months; P<.001). Overall, 27 patients (22.5%) developed postoperative complications. Seven patients (5.8%) died during the postoperative period. CONCLUSIONS: Age of 65 years or older, carcinomatosis, and extensive (bilobar) liver involvement are associated with decreased survival and increased postoperative morbidity and mortality and may negate any potential benefit patients derive from resection of the primary lesion. A substantial number of patients with synchronous hepatic metastases have protracted survival that justifies resection of the primary colorectal tumor at initial presentation. Despite the presence of stage IV disease, resection of the primary tumor and, when feasible, liver metastases is indicated.

Adult↗

Hepatic resection: effective treatment for primary and secondary tumors.

BACKGROUND: Hepatic resection is an accepted therapeutic modality for isolated colorectal metastases (CRM) and primary hepatobiliary cancers (PC). Controversy continues regarding the safety, efficacy, and appropriateness of resection for noncolorectal metastases (NCM). METHODS: A retrospective review of 167 resections in 160 patients was performed to evaluate the impact of demographics and perioperative data on survival and recurrence. Statistical analyses were performed by Student t test, analysis of variance, and Kaplan-Meier survival estimates. RESULTS: Resections were performed for CRM, 110 of 167 (66%), NCM, 31 of 167 (19%), and PC, 26 of 167 (15%). The interval from primary to metastases was significantly longer in the NCM group than the CRM group (34.7+/-45.1 vs. 18.7+/-23.7 months; P<.01). Mean number of lesions was not different between groups; however, NCM were larger than CRM (5.9+/-4.5 vs 4.5+/-2.9 cm; P<.05). Operative complications were significantly greater for PC (54%) versus CRM and NCM (21% and 19%, respectively; P<.01), although length of stay was similar between groups. Perioperative mortality was 2%. Actuarial survival at 1 year, 3 years, and 5 years was CRM 91%, 54%, and 40%, PC 75%, 60%, and 38%, and NCM 68%, 36%, and not available, respectively (CRM vs. NCM; P<.01 at 3 years). CONCLUSIONS: Hepatic resection for primary and secondary malignancy can be performed with minimal morbidity and mortality. Resection of NCM is associated with a lower overall survival compared with CRM and PC. The disease-free interval from resection of the primary to metastasectomy is prolonged and hepatic recurrence infrequent after resection in the NCM group. These results suggest that tumor biology is a critical determinant of outcome after hepatic resection of primary and secondary hepatic tumors.

Aged↗

Management of symptomatic malignant melanoma of the gastrointestinal tract.

BACKGROUND: Melanoma metastatic to the gastrointestinal (GI) tract is asymptomatic or presents with pain, bleeding, or obstruction. To determine whether surgery influences outcomes, we reviewed our experience with this patient population. METHODS: Medical records of patients with metastatic melanoma to the GI tract were reviewed. Patients were divided into four groups, i.e., complete resection, partial debulking, unresectable, or unexplored. Analysis was performed using the Kaplan-Meier method. RESULTS: Fifty patients with melanoma metastatic to the GI tract were identified (40 men and 10 women; mean age, 44 years). Presenting symptoms included pain (62%), bleeding (28%), and obstruction (18%). Diagnosis was confirmed using contrast studies (38%), endoscopy (20%), or computed tomography (30%). Thirty-six patients (61%) underwent a total of 39 operations. Seventeen patients underwent complete resection, whereas 14 underwent partial debulking. Five patients had unresectable lesions, and 14 patients did not undergo exploration because of medical contraindications. The operative mortality rate was 2.5% (1 of 39). The mean survival times for the unexplored and unresected groups were similar (4.1 months). Patients who underwent partial resection exhibited a longer mean survival time (8.9 months) than did patients in the unresected group (P < .001). The complete-resection group demonstrated a mean survival time of 23.5 months, which was significantly longer than that for patients who underwent less than complete resection (P < .0001). CONCLUSIONS: Metastatic melanoma to the GI tract can result in significant morbidity and death. Surgical resection can be performed safely. Patients for whom all sites of disease are completely resected experience significant improvements in survival times, compared with patients who undergo less than complete resection. For selected patients, surgical treatment of metastatic melanoma involving the GI tract is appropriate therapy.

Adult↗

A phase I trial of continuous hyperthermic peritoneal perfusion with tumor necrosis factor and cisplatin in the treatment of peritoneal carcinomatosis.

BACKGROUND: Tumor necrosis factor (TNF), hyperthermia, and cisplatin have synergistic cytotoxicity against cancer cells in vitro. This combination may be well suited to the regional treatment of peritoneal tumor spread in patients. Continuous hyperthermic peritoneal perfusion (CHPP) is a technique that allows uniform delivery of cytotoxic agents and heat to the peritoneal surface. A Phase I trial of CHPP with TNF and cisplatin was conducted to define the maximum tolerated dose (MTD) for TNF and cisplatin under moderate hyperthermia in the treatment of peritoneal carcinomatosis. METHODS: Twenty-seven patients with peritoneal carcinomatosis underwent exploratory laparotomy and tumor debulking followed by a 90-minute CHPP with cisplatin (100-350 mg/m2) and TNF (0-0.3 mg/L). Perfusion parameters included a perfusate volume of 3-9 L, a peritoneal temperature of 42-43 degrees C, and a flow rate of 1.5 L/minute. Sodium thiosulfate was administered systemically during and after the perfusion as a cisplatin binding agent. RESULTS: There was no operative or treatment-related mortality in this study. CHPP resulted in a 14-fold higher area under the concentration versus time curve (AUC) for cisplatin in the perfusate compared with plasma, and a 4854-fold higher AUC for TNF. The MTD was defined as 250 mg/m2 cisplatin plus 0.1 mg/L TNF. The dose-limiting toxicity was renal insufficiency. No other systemic toxicity was identified, and no significant regional toxicity was identified. The median time to toleration of a regular diet was 8 days (range, 5-20 days). CONCLUSIONS: The favorable regional pharmacologic profile of the combination of cisplatin and TNF suggests that these agents administered via CHPP warrant further evaluation as prophylaxis against or treatment for peritoneal carcinomatosis.

Adult↗

The clinical implications of hypophosphatemia following major hepatic resection or cryosurgery.

OBJECTIVES: To determine the incidence and predisposing factors leading to postoperative hypophosphatemia after major hepatic surgery and the consequences of this electrolyte abnormality. DESIGN: A retrospective study. SETTING: A university tertiary care referral center. PATIENTS AND METHODS: Thirty-five consecutive patients undergoing either major hepatic resections or cryosurgery from July 1994 through January 1997 were retrospectively reviewed for the occurrence of hypophosphatemia and postoperative complications. MAIN OUTCOME MEASURES: Prolonged ventilatory support, intensive care unit and hospital stays, and the incidence of postoperative complications. RESULTS: The overall incidence of hypophosphatemia in our series was 21 (67%) of 35 with a mortality rate of 1 (2.8%) in 35. Mean operative time, estimated blood loss, partial vascular occlusion time, and transfusion requirements were similar between the hypophosphatemic and the nonhypophosphatemic groups. The presence of postoperative complications was significantly greater in the hypophosphatemic group (17 [80%] of 21) vs the nonhypophosphatemic group (4 [28%] of 14) (P<.05). The incidence of antacid use in the hypophosphatemic group (14 [66%] of 21) was significantly higher than the use in the nonhypophosphatemic group (2 [14%] of 14) (P<.05). CONCLUSIONS: Hypophosphatemia commonly occurs in major hepatic procedures. The presence of moderate hypophosphatemia is associated with the use of antacid therapy but no other perioperative or operative variables. The occurrence of hypophosphatemia correlates with an increased incidence of postoperative complications. Awareness of this entity can direct aggressive replacement of phosphates and avert the occurrence of severe hypophosphatemia and associated complications.

Adult↗