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Alan J Koffron

Publications and source records attributed to Alan J Koffron.

13 recordsLinked to original sources
PubMed2006

Proposed classification of complications after live donor nephrectomy.

OBJECTIVES: A standardized classification for the potential complications of living donor nephrectomy is an essential step in establishing a construct for monitoring and reporting the outcomes of this procedure. It is also helpful in informing potential donors about the inherent risks of the donor operation as part of the informed choice process. METHODS: We reviewed 600 laparoscopic live donor nephrectomies performed at our center. A modification of the Clavien classification system describing procedure-related complications was developed and used to grade the severity of all complications. RESULTS: We observed 43 complications (7.2%) in our series of 600 patients. Grade 1 defines all events that, if left untreated, would have a spontaneous resolution or needed a simple bedside procedure (39.5%). Grade 2 complications differ from grade 1 in that they are potentially life-threatening and usually require some form of intervention, but do not result in ongoing disability. We subdivided grade 2 complications (55.8% in our study) into 2a, 2b, and 2c. The latter describes complications requiring open conversion of laparoscopic donor nephrectomy for patient treatment. Grade 3 complications are events with residual or lasting disability (4.7% in our review). Grade 4 events are those resulting in renal failure or death because of any complication (none occurred in our series). CONCLUSIONS: A graded classification scheme for reporting the complications of donor nephrectomy may be useful for maintaining registry information on donor outcomes and when informing potential donors about the risks and benefits of this procedure.

Humans↗
PubMed2005

Liver graft volume estimation in 100 living donors: measure twice, cut once.

Estimation of graft volume (GV) is critical in living donor liver transplantation. This study examines the accuracy of formula-derived GV estimates and compares them to both radiogically-derived estimates and actual measurements. We first compared formula-derived estimates of GV and compared them to actual volumes to provide estimates for both right lobe (RL) and left lateral segment (LLS) GV. We then applied these formulae to a validation cohort. Finally, we evaluated both formula-derived and radiologically-derived estimates by comparing them to actual GV measurements. There is a marginal concordance between formula-derived calculation and GV for RL donors, but the error ratio was lower than for radiologic estimates. In contrast, MRI measurements for LLS grafts demonstrated a lower error ratio than formula-derived estimation. Formula-derived estimates of GV should be routinely used in the initial screening of potential living donors as long as their limitations are appreciated.

Biometry↗
PubMed2005

Liver transplantation with simultaneous removal of an intracardiac transjugular intrahepatic portosystemic shunt and a vena cava filter without the utilization of cardiopulmonary bypass.

Transjugular intrahepatic shunts (TIPSs) are widely used in the management of portal hypertension complications including variceal bleeding, refractory ascites, and hepatic hydrothorax. Vena cava filters (VCFs) are an important therapeutic modality in the prevention of pulmonary emboli in patients suffering deep venous thrombosis and clinical contraindications for anticoagulation. Stent and filter misplacement or migration may occur, complicating liver transplantation (LT) surgery. We describe the intraoperative management of a patient with cirrhosis, who had a TIPS extending into the right atrium (RA) and a retrohepatic VCF. Stent and filter removals were deferred until the time of LT. Both procedures were performed successfully by complete cava and portal reconstruction. In conclusion, careful assessment and surgical management of patients with stent and filters permits successful LT.

Adult↗
PubMed2005

The economic impact of MELD on liver transplant centers.

Adoption of the model for end stage liver disease (MELD) system prioritized patients awaiting liver transplant (LT) by severity of illness including progressive renal dysfunction. Unfortunately, current reimbursement for LT is not adjusted by severity of illness or need for simultaneous liver-kidney transplantation (LKT). This study examines hospital cost and reimbursement for LT and LKT to determine the effect of MELD on transplant center (TC) financial outcomes given current reimbursement practices as well as DRG outlier threshold limits. LT was performed for 86 adults prior to and 127 following the implementation of MELD. Between the eras, there was a substantial increase in the average laboratory MELD score (17.1 to 20.7 p=0.004) and percentage of LKTs performed (5.8% to 17.3% p=0.01). Increasing MELD score was associated with higher costs ($4309 per MELD point p<0.001) and decreasing TC net income ($1512 per MELD point p<0.001). In patients not achieving the Medicare outlier status, predicted net loss was $17,700 for high-MELD patients and $19,133 for those needing LKT. In conclusion, contractual reimbursement agreements that are not indexed by severity of disease may not reflect the increased costs resulting from the MELD system. Even with outlier thresholds, Medicare reimbursement is inadequate resulting in a net loss for the TC.

Aged↗
PubMed2004

Comparative analysis of live liver donation risk using a comprehensive grading system for severity.

We investigated whether right lobe (RL) liver donation is associated with a higher incidence or severity of donor complications than left lobe (LL) liver and left lateral segment (LLS) liver donations. We studied 80 living donors: 35 RL liver donors and 45 LL/LLS liver donors. A modification of the Clavien classification was used to grade the severity of complications. RL and LL/LLS liver donations had equivalent blood loss, readmission and reoperation rates, use of blood products, and lengths of stay in the intensive care unit and hospital. RL liver donors underwent longer surgeries and experienced more postoperative pain than LL/LLS liver donors. The overall rate of complications was 33%. There was a higher rate of complications in RL liver donors (51%) than LL/LLS liver donors (20%). When graded by severity, there were more grade 2 complications in RL liver donors than in LL/LLS liver donors. Our report confirms that RL liver donation is associated with higher morbidity than LL/LLS liver donation. When the complications are systematically graded by severity, there is a significant difference in Clavien grade 2 complications in RL liver donors.

Adult↗
PubMed2004

Laparoscopic donor nephrectomy 1997 to 2003: lessons learned with 500 cases at a single institution.

BACKGROUND: Laparoscopic live donor nephrectomy (LDN) is a less invasive alternative to traditional open nephrectomy that has several potential advantages. However, there have been few large series reports describing the complications of LDN and the details of their management. METHODS: We performed a retrospective review of 500 LDNs performed at our center between October 1997 and September 2003. We evaluated preoperative donor characteristics, intraoperative parameters and complications, and postoperative recovery and complications. A modification of the Clavien classification was developed and used to grade the severity of all complications. RESULTS: The overall rate of intraoperative complications was 2.8%. There were 9 open conversions (1.8%), of which 6 were in the first 100 cases. Six of the 9 open conversions were for management of complications; 3 were elective. Seven renovascular incidents (1.4%) all required open conversion except one. The overall rate of postoperative complications was 3.4%. Thirty of 500 patients in our LDN series experienced an intraoperative or procedure-related complication (6.0%). When graded by severity, 18 of 31 (58.1%) of all complications were grade 1, 11 of 31 (35.4%) grade 2, and 2 of 31 (6.5%) grade 3. Only 1 recipient experienced delayed graft function, and only 1 recipient had a urologic complication. CONCLUSIONS: Our series supports the safety and efficacy of LDN with very low intraoperative complication and conversion rates. Most of the intraoperative complications can be managed laparoscopically. Readmissions are extremely rare (1.5%). Aberrant vascular anatomy and obesity are not contraindications to LDN, but they require experience. With careful surgical technique, delayed graft function and urologic complications in recipients can be avoided. A graded classification scheme for reporting complications of donor nephrectomy might be useful for maintaining registry information on donor outcomes and when informing potential donors about the risks and benefits of this procedure.

Adolescent↗
PubMed2003

Penetrating injuries of the subclavian artery.

BACKGROUND: Penetrating injuries of the subclavian artery occurs infrequently but represent a surgical challenge. We reviewed our experience with penetrating injury of the subclavian artery and identify factors that influenced morbidity and mortality. METHODS: A retrospective review was performed on 54 consecutive patients who sustained penetrating injury to the subclavian artery during a 10-year period. RESULTS: The causes of injuries were gunshot wounds in 46 patients (85%), stab wounds in 5 patients (9%), and shotgun wounds in 3 patients (6%). The overall mortality was 39%. Operative management of the subclavian artery injury included primary repair in 38 patients, interposition grafting in 13 patients, and ligation in 3 patients. The most common associated injury was subclavian vein (44%) followed by brachial plexus (31%). Predictors of survivability include mechanism of penetrating injuries, hemodynamic status of patients on arrival, and three or more associated injuries involving other structures. Associated brachial plexus injury accounts for the majority of long-term morbidity in survivors. CONCLUSIONS: Penetrating injuries of the subclavian artery are associated with high morbidity and mortality. Multiple concomitant injuries, unstable vital signs upon presentation, and gun shot injuries greatly increase mortality.

Adolescent↗
PubMed2003

Dual-echo, chemical shift gradient-echo magnetic resonance imaging to quantify hepatic steatosis: Implications for living liver donation.

In living liver donation, a fatty liver poses risks for both recipient and donor. Currently, liver biopsy is the standard for assessing the presence and extent of steatosis. The goals of this study were to correlate a steatosis index derived from magnetic resonance imaging (MRI) to the histologic grade on biopsy as well as to determine the topographic distribution of steatosis within the liver. We examined the ability of dual-echo, chemical shift gradient-echo MRI to predict the degree of steatosis on liver biopsy. A total of 22 subjects received both a liver biopsy and detailed MRI evaluation. These individuals included 15 potential living donors and 7 patients with nonalcoholic fatty liver disease. MRI steatosis index was then compared with histologic grade on liver biopsy. The topographic distribution of hepatic steatosis was determined from those subjects in whom MRI detected hepatic steatosis. The steatosis index had a positive correlation with grade of steatosis on liver biopsy (correlation coefficient, 0.84). There was no significant variation in the degree of steatosis among segments. A steatosis index of >0.2 had good positive and negative predictive value for the presence of significant steatosis (>15%) on biopsy. Our quantitative MRI protocol can predict the degree of hepatic steatosis when it is minimal to moderate, and may obviate the need for liver biopsy for the purpose of quantification of steatosis in living donors. Fat saturation added to the MRI protocol may further improve diagnostic accuracy. This technique may be applicable to the larger population with hepatic steatosis.

Adult↗
PubMed2003

Transluminal stent graft repair with Wallgraft endoprosthesis in a porcine arteriovenous graft pseudoaneurysm model.

PURPOSE: Pseudoaneurysm is a known complication of arteriovenous grafts in chronic hemodialysis and can result in graft disruption or thrombosis if left untreated. This study evaluated the safety and efficacy of endovascular repair with Wallgraft endoprosthesis (Boston Scientific, Inc, Watertown, Mass) in a porcine arteriovenous graft (AVG) pseudoaneurysm model. MATERIALS AND METHODS: Bilateral groin AVG pseudoaneurysms (n = 18) were created with an oversized Dacron interposition graft within a polytetrafluoroethylene femoral AVG in nine domestic swine and allowed to mature 28 +/- 4 days (standard deviation). Transluminal placement of Wallgraft was performed to exclude the pseudoaneurysm from the AVG circulation. Hemodialysis was performed (400 mL/min x 1 hour, with intravenous heparin 30 units/kg) every 4 days for a total of 6 weeks via 15-gauge needles in the treated AVG pseudoaneurysm site. Arteriography and duplex ultrasound scan were performed to determine AVG patency and pseudoaneurysm flow. Histologic evaluation was performed to determine Wallgraft morphology. In vitro pulsatile flow chamber was used to determine maximal flow volume without peri-Wallgraft endoleak. RESULTS: All AVG pseudoaneurysms were successfully excluded with the Wallgrafts. Twelve AVG (67%) remained patent at the completion of the study. No Wallgraft migration occurred from hemodialysis. Transient peri-Wallgraft endoleak (<2 hours after hemodialysis) was present in 13 of 18 (72%) and four of 12 (33%) AVG pseudoaneurysms by weeks 1 and 6, respectively. With maintenance of an intraluminal pressure of 80, 100, 120, 140, and 160 mm Hg in the pulsatile flow chamber, the maximal flow rates without peri-Wallgraft endoleak were 625 +/- 120, 650 +/- 145, 620 +/- 95, 425 +/- 110, and 262 +/- 86 mL/min. Scanning electron microscopy showed a neointimal layer covered with thrombus on the Wallgraft surface. CONCLUSION: Endoluminal placement of Wallgraft endoprosthesis provides adequate structural support for continuous hemodialysis after AVG pseudoaneurysm exclusion. Transient blood flow in the pseudoaneurysm cavity may occur immediately after the hemodialysis, which may represent the effect of heparin used during hemodialysis. This study suggests Wallgraft is a safe and effective treatment for AVG pseudoaneurysm and permits continuous hemodialysis.

Aneurysm, False↗
PubMed2002

A prospective study of rapid corticosteroid elimination in simultaneous pancreas-kidney transplantation: comparison of two maintenance immunosuppression protocols: tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus.

BACKGROUND: We examined the feasibility of rapid corticosteroid elimination in simultaneous pancreas kidney transplantation. METHODS: Forty consecutive simultaneous pancreas-kidney (SPK) transplant recipients were enrolled in a prospective study in which antithymocyte globulin induction and 6 days of corticosteroids were administered along with tacrolimus and MMF (n=20) or tacrolimus and sirolimus (n=20). Mean+/-SD follow-up for recipients receiving tacrolimus/MMF and tacrolimus/sirolimus were 12.7+/-3.9 and 13.4+/-2.9 months, respectively. Patient and graft survival, and rejection rates were compared to an historical control group (n=86; mean follow-up 41.5+/-15.4 months) of SPK recipients that received induction and tacrolimus, MMF, and corticosteroids. RESULTS: Demographic characteristics of recipient and donor variables were similar among all groups. The 1-year actuarial patient, kidney, and pancreas survival rates in the 40 SPK transplant recipients with rapid corticosteroid elimination were 100, 100, and 100%, respectively. In the historical control group the 1-year actual patient, kidney, and pancreas survival rates were 96.5, 93.0, and 91.9%, respectively. The 1-year rejection-free survival rate recipients in the rapid steroid elimination group collectively was 97.5 vs 80.2% in the historical control group (P=0.034). At 6 and 12 months posttransplant the serum creatinine values remained stable in all groups. CONCLUSIONS: We conclude that chronic corticosteroid exposure is not required in SPK transplant recipients receiving antithymocyte globulin induction and maintenance immuno-suppression consisting of either tacrolimus and mycophenolate mofetil or tacrolimus and sirolimus.

Adolescent↗
PubMed2002

Technical and immunologic progress in simultaneous pancreas-kidney transplantation.

BACKGROUND: During the past few years the use of new immunosuppressants and refinements in surgical technique of simultaneous pancreas-kidney (SPK) transplantation have resulted in markedly improved outcomes. This is a retrospective study of 208 SPK transplants performed at Northwestern University, demonstrating the advances made at a single center that are reflective of the field at large. METHODS: An 8.5-year time span was split into 4 distinct eras marking sequential changes in immunosuppression and surgical technique that ensued. SPK transplant outcomes of patient and graft survival and rejection rates were compared. Also examined were end points related to the changing risk profile of the recipients, as well as quality of allograft function and rates of rehospitalizations. RESULTS: Recipients receiving tacrolimus/mycophenolate mofetil-based immunosuppression had patient, kidney, and pancreas survival rates significantly higher than those of earlier cohorts. The elimination of corticosteroids did not reduce survival rates or increase rejection risk. The use of pancreatic exocrine enteric drainage technique over bladder drainage reduced rehospitalizations. CONCLUSIONS: Advances in immunosuppression management combined with technical refinements have made SPK transplantation a safer and more effective treatment option for the diabetic, uremic patient.

Adolescent↗