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Ischemic Time (ischemic + time)
Kinds of Ischemic Time Selected AbstractsEffects of Tisseel and FloSeal on Primary Ischemic Time in a Rat Fasciocutaneous Free Flap Model,THE LARYNGOSCOPE, Issue 2 2004Aaron W. Partsafas BS Abstract Objectives: Free flaps are the technique of choice for reconstruction of defects resulting from extirpation of tumors of the head and neck. Advances in microsurgical technique have resulted in success rates of greater than 95%. Numerous intraoperative factors, ranging from technical issues to topically applied agents, can complicate the outcome of microsurgical free tissue transfer. Synthetic tissue adhesives and hemostatic agents are playing an ever-increasing role in reconstructive surgery. The safety of these factors in free flap surgery has not been ascertained. Study Design: Animal Care Committee live rat model. Methods: Male Sprague-Dawley rats were divided into three groups: group I, Control; group 2, FloSeal; group 3, Tisseel. In each group, a 3 × 6 cm ventral fasciocutaneous groin flap based on the left superficial epigastric artery was elevated and the experimental material applied beneath the flap and around the flap pedicle prior to suturing of the flap back to the wound bed. The experimental materials consisted of 0.2 mL saline in the control group, 0.5 mL FloSeal, and 0.2 mL Tisseel. In phase I of this study, the effect of each treatment on flap survival was assessed by survival at postoperative day 4. In phase II of the study, the effects of these agents on ischemic tolerance was investigated. Five rats in each treatment group were exposed to ischemic times of 6, 8, 10, and 12 hours. Survival of the flap was assessed 7 days after reversal of the ischemia. Probit curves and the critical ischemic time (CIT50) were calculated. Results: All flaps survived the 2-hour period of ischemia and were viable at postoperative day 4. Flap survival from group 1 (Control), group 2 (FloSeal), and group 3 (Tisseel) at the various ischemic times was as follows: at 6 hours, 80%, 80%, and 80%, respectively; at 8 hours, 80%, 80%, 60%; at 10 hours, 60%, 33%, 40%; at 12 hours, 20%, 20%, 0%. The CIT50 for the Control, FloSeal, and Tisseel groups was 9.4, 9.0, and 7.0 hours, respectively. Conclusions: FloSeal, a thrombin-based hemostatic agent, and Tisseel, a fibrin glue, displayed no adverse effect on flap survival in this model. [source] Evaluation of renal function after laparoscopic partial nephrectomy with renal scintigraphy using 99mtechnetium-mercaptoacetyltriglycineINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2006KOBAYASHI YASUYUKI Aim: We evaluated the functions of an affected kidney after laparoscopic partial nephrectomy (LPN) using renal scintigraphy with 99mtechnetium-mercaptoacetyltriglycine (99mTc-MAG3). Methods: Split renal function of 10 patients who underwent LPN for renal tumors was assessed using renal scintigraphy with 99mTc-MAG3 before surgery, and 1 week and 3 months post-surgery. Results: Median operating time was 196.5 min, median tumor diameter was 2.3 cm, mean blood loss was 64 mL and mean ischemic time was 38.5 min. Median change in serum creatinine level pre- to post-surgery was 0.15 mg/dL. Median contribution of the affected kidney to total renal function (calculated using 99mTc-MAG3) was 50.0%, 41.7% and 36.1% before surgery, 1 week and 3 months after LPN, respectively. In one patient, the tumor was resected after cooling of the affected kidney with ice slush for 15 min, and the split renal function ratio remained as high as 50% at 3 months post-operatively despite a total ischemic time of 61 min. Conclusions: This paper evaluated renal function on the affected side before and after surgery by measuring split renal function with renal scintigraphy using 99mTc-MAG3. Risk factors for renal dysfunction in the affected kidney after LPN include age over 70 years with more than 30 min warm ischemic time, re-clamping of the renal artery procedure, and a warm ischemic time greater than 60 min. We believe that renal cooling with slush ice prevents renal dysfunction of the affected kidney after LPN with longer warm ischemic times. However, an easier renal cooling technique should be sought for regular use of cooling procedures in LPN. [source] Critical ischemic time for the rat ovary: Experimental study evaluating early histopathologic changesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2009Ayhan Coskun Abstract The aim of the present study was to determine a critical ischemic time for ovary in an experimental study in rats. An experimental model using slip-knot tying of all ovarian arteries and veins in cycling female rats was developed. Rat ovaries were tied using the technique through an explorative laparotomy. Complete ischemia times of 1, 2 and 3 h were used for the study. At the end of the ischemic times, the ovaries were harvested following 1 h of reperfusion. Histology indicated a gradually increased congestion correlating with the respective increased ischemic times. According to the present findings 2 h complete ischemia yields a significant injury. The model used in the present study may be used for complete ischemia,reperfusion injury of the rat ovary. [source] Extended right liver grafts obtained by an ex situ split can be used safely for primary and secondary transplantation with acceptable biliary morbidityLIVER TRANSPLANTATION, Issue 7 2009Atsushi Takebe Split liver transplantation (SLT) is clearly beneficial for pediatric recipients. However, the increased risk of biliary complications in adult recipients of SLT in comparison with whole liver transplantation (WLT) remains controversial. The objective of this study was to investigate the incidence and clinical outcome of biliary complications in an SLT group using split extended right grafts (ERGs) after ex situ splitting in comparison with WLT in adults. The retrospectively collected data for 80 consecutive liver transplants using ERGs after ex situ splitting between 1998 and 2007 were compared with the data for 80 liver transplants using whole liver grafts in a matched-pair analysis paired by the donor age, recipient age, indications, Model for End-Stage Liver Disease score, and high-urgency status. The cold ischemic time was significantly longer in the SLT group (P = 0.006). As expected, bile leakage from the transected surface occurred only in the SLT group (15%) without any mortality or graft loss. The incidence of all other early or late biliary complications (eg, anastomotic leakage and stenosis) was not different between SLT and WLT. The 1- and 5-year patient and graft survival rates showed no statistical difference between SLT and WLT [83.2% and 82.0% versus 88.5% and 79.8% (P = 0.92) and 70.8% and 67.5% versus 83.6% and 70.0% (P = 0.16), respectively]. In conclusion, ERGs can be used safely without any increased mortality and with acceptable morbidity, and they should also be considered for retransplantation. The significantly longer cold ischemic time in the SLT group indicates the potential for improved results and should thus be considered in the design of allocation policies. Liver Transpl 15:730,737, 2009. © 2009 AASLD. [source] Sirolimus-based immunosuppression following liver transplantation for hepatocellular carcinomaLIVER TRANSPLANTATION, Issue 5 2008Michael A. Zimmerman Experience with sirolimus (SRL)-based immunosuppression following orthotopic liver transplantation (OLT) is rapidly accumulating. In combination with calcineurin inhibitors (CNIs), SRL may reduce the incidence of acute rejection and lower overall required drug levels. This study sought to quantify long-term outcome following OLT in patients with cirrhosis and concomitant hepatocellular carcinoma (HCC) who were treated with an SRL-based regimen as a primary therapy. From January 2000 to June 2007, 97 patients underwent OLT for end-stage liver disease and HCC at the University of Colorado Health Sciences Center. Of those, 45 patients received SRL, in addition to CNIs, as a component of their primary immunosuppression regimen post-OLT. Conversely, 52 patients received the standard immunosuppression regimen including CNIs, mycophenolate mofetil, and corticosteroids. The 2 treatment groups were compared with respect to the following variables: age, gender, tumor stage by explant, grade, size, presence of vascular invasion, focality, Child's class, baseline creatinine, and warm and cold ischemic times. The 2 groups were comparable by all factors save for cold ischemic time, which was significantly longer in the CNI-treated group. Overall survival at 1 and 5 years post-OLT for patients treated with SRL was 95.5% and 78.8%, respectively. Conversely, survival in patients treated with CNIs exclusively at the same time intervals was 83% and 62%. Although there was no difference in the incidence of major complications, the SRL group experienced a modest improvement in renal function. Cumulatively, these data suggest a potential survival benefit with SRL-based therapy in patients undergoing OLT for end-stage liver disease and concomitant malignancy. Liver Transpl 2008. © 2008 AASLD. [source] Recurrence of hepatitis C infection: Where are we now?LIVER TRANSPLANTATION, Issue S2 2005Michael Charlton Key Points 1Hepatitis C-associated liver failure is the most common indication for liver transplantation, and approximately 10% of HCV-infected recipients will die or lose their allograft secondary to recurrent HCV infection. 2Risk factors associated with histological recurrence of HCV include donor (age, fat content, ischemic time, and living donor), recipient (age and non-Caucasian race), clinical (rejection and CMV), and viral (viral load and quasispecies). 3Treatment of recipients with histological recurrence is with pegylated IFN (± ribavirin). The role of hepatitis C immunoglobulin in the management of postransplant HCV is still evolving. (Liver Transpl 2005;11:S57,S62.) [source] Alternatives to the double vena cava method in partial liver transplantationLIVER TRANSPLANTATION, Issue 1 2005Yoji Kishi Minimizing graft congestion in partial liver transplantation is important, especially when the graft weight is marginal for the recipient metabolic demand. We prefer the double vena cava technique for reconstructing middle hepatic vein tributaries with thick, short hepatic veins because the technique can reduce the warm ischemic time of the graft and make a wide anastomosis. This technique requires a cryopreserved superior or inferior vena cava. We devised an alternative double vena cava method using iliac or femoral vein grafts and applied it to two right liver transplantation patients. There was no postoperative hepatic venous outflow block in either patient. In conclusion, application of this technique, even in the absence of a suitable vena cava, can help to minimize graft congestion. (Liver Transpl 2005;11:101,103.) [source] Significance of positive cytotoxic cross-match in adult-to-adult living donor liver transplantation using small graft volumeLIVER TRANSPLANTATION, Issue 12 2002Kyung-Suk Suh MD A positive cross-match in cadaveric liver transplantation is relatively acceptable, but its role in living donor liver transplantation (LDLT) is less well known. The aim of this study is to examine the significance of cytotoxic cross-match in adult-to-adult LDLT using small-for-size grafts. Forty-three adult-to-adult LDLTs were performed at Seoul National University Hospital (Seoul, Korea) from January 1999 to July 2001. Subjects consisted of 27 men and 16 women with an average age of 45.4 years. Average liver graft weight was 565.3 ± 145.7 g, and average graft-recipient weight ratio (GRWR) was 0.89% ± 0.20%. HLA cross-match testing by lymphocytotoxicity and flow cytometry was performed routinely preoperatively. Factors that may influence survival, such as age; sex; blood group type A, type B, type O compatibility; cytotoxic cross-match; donor age; surgical time; cold ischemic time; and GRWR, were analyzed. Nine patients (20.9%) died in the hospital. There was a greater in-hospital mortality rate in women than men (37.5% v 11.1%; P = .049). The extra-small,graft group (0.54% , GRWR < 0.8%; n = 14) showed greater in-hospital mortality rates than the small-graft group (0.8% , GRWR , 1.42%; n = 29; 42.9% v 10.3%; P = .022). A positive cross-match was detected in 4 women transplant recipients, and 3 of these patients belonged to the extra-small,graft group. All patients with a positive cross-match died of multiorgan failure after early postoperative acute rejection episodes. Positive cross-match was the only significant factor in multivariate analysis (P = .035). In conclusion, when lymphocytotoxic cross-match and flow cytometry are significantly positive, adult-to-adult LDLT using small-for-size grafts should not be performed. [source] Outcome of the use of pediatric donor livers in adult recipientsLIVER TRANSPLANTATION, Issue 1 2001Motohiko Yasutomi The prolonged waiting time caused by the lack of donor livers leads to an increasing number of terminally ill patients waiting for lifesaving liver transplantation. To rescue these patients, transplant programs are accepting donor organs from the expanded donor pool, using donors of increasingly older age, as well as from the pediatric age group, often despite significant mismatch in liver size. We investigated the outcome of 102 consecutive liver transplantations using pediatric donor livers in adult recipients. One-year graft survival using donors aged 12 years or younger (group 1, n = 14) and donors aged 12 to 18 years (group 2, n = 88) was compared. In addition, risk factors for graft loss and vascular complications were analyzed. The 1-year graft survival rate in adult transplant recipients in group 1 was 64.3% compared with 87.5% in those in group 2 (P = .015). The main cause of graft loss was arterial complications, occurring in 5 of 16 transplant recipients (31.3%). Major risk factors for graft loss and vascular complications were related to the size of the donor: age, height and weight, body surface area of donor and recipient, and warm ischemic time. We conclude that the outcome of small pediatric donor livers in adult recipients is poor, mainly because of the increased incidence of arterial complications. When a pediatric donor is used in an adult recipient, ischemic time should be kept to a minimum and anticoagulative therapy should be administered in the immediate postoperative period to avoid arterial complications. However, because small pediatric donors are the only source of lifesaving organs for the infant recipient, the use of small pediatric donor livers in adults should be avoided. [source] Retransplantation for late liver graft failure: Predictors of mortalityLIVER TRANSPLANTATION, Issue 2 2000Marcelo Facciuto As patient survival after orthotopic liver transplantation (OLT) improves, late complications, including late graft failure, more commonly occur and retransplantation (re-OLT) is required more often. Survival after re-OLT is poorer than after primary OLT, and given the organ shortage, it is essential that we optimize our use of scarce donor livers. We sought to identify variables that predict poor outcome after late re-OLT. Among adults who underwent OLT between September 1989 and October 1997, we identified transplant recipients who survived greater than 6 months (n = 964) and analyzed those who required late re-OLT (,6 months after primary OLT). We recorded the indication for the initial OLT and interval from OLT to re-OLT. We also analyzed data collected at the time of re-OLT, including age, sex, indications for primary OLT and re-OLT, United Network for Organ Sharing status, preoperative laboratory values (white blood cells, platelets, hemoglobin, albumin, bilirubin, creatinine, and prothrombin time), Child-Pugh-Turcotte score, number of rejection episodes before re-OLT, and interval between OLT and re-OLT. In addition, we analyzed surgical factors (including procedure performed and use of packed red blood cells, fresh frozen plasma, and platelets), postoperative immunosuppression, and donor factors (age, ischemic time). Forty-eight patients (5%) underwent late re-OLT at a median of 557 days (range, 195 to 2,559 days) post-OLT. Survival rates after re-OLT at 90 days, 1 year, and 5 years were 71%, 60%, and 42%, respectively. Patients surviving 90 days or greater after re-OLT had an 85% chance of surviving to 1 year. Sepsis was the leading cause of death (15 of 25 deaths; 60%). Recipient age older than 50 years (P = .04), preoperative creatinine level greater than 2 mg/dL (P = .004), and use of intraoperative blood products (packed red blood cells, P = .001; fresh frozen plasma, P = .002; platelets, P = .004) had significant impacts on survival. Late re-OLT was associated with increased mortality. Careful patient selection, with particular attention to recipient age and renal function, may help improve results and optimize our use of scarce donor livers. [source] Orthotopic liver transplantation for children with Alagille syndromePEDIATRIC TRANSPLANTATION, Issue 5 2010Ronen Arnon Arnon R, Annunziato R, Miloh T, Suchy F, Sakworawich A, Hiroshi S, Kishore I, Kerkar N. Orthotopic liver transplantation for children with Alagille syndrome. Pediatr Transplantation 2010: 14:622,628. © 2010 John Wiley & Sons A/S. Abstract:, AGS is an inherited disorder involving the liver, heart, eyes, face, and skeleton. Aim: To determine the outcome of LT in children with AGS compared to those with BA. Methods: Children with AGS and BA who had a LT between 10/1987 and 5/2008 were identified from the UNOS database. Results: Of 11 467 children who received a liver transplant, 461 (4.0%) had AGS and 3056 (26.7%) had BA. One- and five-yr patient survival was significantly lower in patients with AGS in comparison with patients with BA (AGS; 82.9%, 78.4%, BA; 89.9%, 84%, respectively). Early death (<30 days from transplant) was significantly higher in AGS than in BA. One- and five-yr graft survival was significantly lower in AGS than in BA (AGS; 74.7%, 61.5%, BA; 81.6%, 70.0%, respectively). Death from graft failure, neurological, and cardiac complications was significantly higher in patients with AGS than in patients with BA. Serum creatinine at transplant, prior LT, and cold ischemic time >12 h were identified as risk factors for death. Conclusion: Children with AGS were older at the time of LT and their one- and five-yr patient and graft survival were significantly lower compared to BA. Risk factors for poor outcome in AGS after LT were identified. [source] Effects of Tisseel and FloSeal on Primary Ischemic Time in a Rat Fasciocutaneous Free Flap Model,THE LARYNGOSCOPE, Issue 2 2004Aaron W. Partsafas BS Abstract Objectives: Free flaps are the technique of choice for reconstruction of defects resulting from extirpation of tumors of the head and neck. Advances in microsurgical technique have resulted in success rates of greater than 95%. Numerous intraoperative factors, ranging from technical issues to topically applied agents, can complicate the outcome of microsurgical free tissue transfer. Synthetic tissue adhesives and hemostatic agents are playing an ever-increasing role in reconstructive surgery. The safety of these factors in free flap surgery has not been ascertained. Study Design: Animal Care Committee live rat model. Methods: Male Sprague-Dawley rats were divided into three groups: group I, Control; group 2, FloSeal; group 3, Tisseel. In each group, a 3 × 6 cm ventral fasciocutaneous groin flap based on the left superficial epigastric artery was elevated and the experimental material applied beneath the flap and around the flap pedicle prior to suturing of the flap back to the wound bed. The experimental materials consisted of 0.2 mL saline in the control group, 0.5 mL FloSeal, and 0.2 mL Tisseel. In phase I of this study, the effect of each treatment on flap survival was assessed by survival at postoperative day 4. In phase II of the study, the effects of these agents on ischemic tolerance was investigated. Five rats in each treatment group were exposed to ischemic times of 6, 8, 10, and 12 hours. Survival of the flap was assessed 7 days after reversal of the ischemia. Probit curves and the critical ischemic time (CIT50) were calculated. Results: All flaps survived the 2-hour period of ischemia and were viable at postoperative day 4. Flap survival from group 1 (Control), group 2 (FloSeal), and group 3 (Tisseel) at the various ischemic times was as follows: at 6 hours, 80%, 80%, and 80%, respectively; at 8 hours, 80%, 80%, 60%; at 10 hours, 60%, 33%, 40%; at 12 hours, 20%, 20%, 0%. The CIT50 for the Control, FloSeal, and Tisseel groups was 9.4, 9.0, and 7.0 hours, respectively. Conclusions: FloSeal, a thrombin-based hemostatic agent, and Tisseel, a fibrin glue, displayed no adverse effect on flap survival in this model. [source] Recurrent Primary Biliary Cirrhosis After Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010M. G. Silveira Recurrent primary biliary cirrhosis (PBC) is an important clinical outcome after liver transplantation (LT) in selected patients. Prevalence rates for recurrent PBC (rPBC) reported by individual LT programs range between 9% and 35%. The diagnostic hallmark of rPBC is histologic identification of granulomatous changes. Clinical and biochemical features are frequently absent with rPBC and cannot be used alone for diagnostic purposes. Some of the risk factors of rPBC may include recipient factors such as age, gender, HLA status and immunosuppression, as well as donor factors such as age, gender and ischemic time, although controversy exists. Most patients have early stage disease at the time of diagnosis, and there may be a role for therapy with ursodeoxycholic acid. While short- and medium-term outcomes remain favorable, especially if compared to patients transplanted for other indications, continued follow-up may identify reduced long-term graft and patient survival. [source] Fate of the Mate: The Influence of Delayed Graft Function in Renal Transplantation on the Mate RecipientAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2009J. F. Johnson Delayed graft function (DGF) in a deceased-donor renal recipient is associated with allograft dysfunction 1-year posttransplant. There is limited research about the influence to allograft function on the mate of a DGF recipient over time. Using a retrospective cohort design, we studied 55 recipients from a single center. The primary outcome was the change in glomerular filtration rate (GFR) 1-year posttransplant. The secondary outcome was the GFR at baseline. We found that mates to DGF recipients had a mean change in GFR 1-year posttransplant of ,11.2 mL/min, while the control group had a mean change of ,0.4 mL/min. The difference in the primary outcome was significant (p = 0.025) in a multivariate analysis, adjusting for cold ischemic time, panel reactive antibody level, allograft loss, human leukocyte antibody (HLA)-B mismatches and HLA-DR mismatches. No significant difference between groups was found in baseline GFR. In conclusion, mates to DGF recipients had a significantly larger decline in allograft function 1-year posttransplant compared to controls with similar renal function at baseline. We believe strategies that may preserve allograft function in these,at-risk'recipients should be developed and tested. [source] Increased Primary Non-Function in Transplanted Deceased-Donor Kidneys Flushed with Histidine-Tryptophan-Ketoglutarate SolutionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2009R. B. Stevens Histidine-Tryptophan-Ketoglutarate (HTK) solution is increasingly used to flush and preserve organ donor kidneys, with efficacy claimed equivalent to University of Wisconsin (UW) solution. We observed and reported increased graft pancreatitis in pancreata flushed with HTK solution, which prompted this review of transplanting HTK-flushed kidneys. We analyzed outcomes of deceased-donor kidneys flushed with HTK and UW solutions with a minimum of 12 months follow-up, excluding pediatric and multi-organ recipients. We evaluated patient and graft survival and rejection rates, variables that might constitute hazards to graft survival and renal function. Two-year patient survival, rejection, renal function and graft survival were not different, but early graft loss (<6 months) was worse in HTK-flushed kidneys (p < 0.03). A Cox analysis of donor grade, cold ischemic time, panel reactive antibodies (PRA), donor race, first vs. repeat transplant, rejection and flush solution showed that only HTK use predicted early graft loss (p < 0.04; relative risk = 3.24), almost exclusively attributable to primary non-function (HTK, n = 5 (6.30%); UW, n = 1 (0.65%); p = 0.02). Delayed graft function and early graft loss with HTK occurred only in lesser grade kidneys, suggesting it should be used with caution in marginal donors. [source] Living Donor and Split-Liver Transplants in Hepatitis C Recipients: Does Liver Regeneration Increase the Risk for Recurrence?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2005Abhinav Humar Concern exists that partial liver transplants (either a living donor [LD] or deceased donor [DD] in hepatitis C virus (HCV)-positive recipients may be associated with an increased risk for recurrence. From 1999 to 2003, at our institution, 51 HCV-positive recipients underwent liver transplants: 32 whole-liver (WL) transplants, 12 LD transplants and 7 DD split transplants. Donor characteristics differed in that WL donors were older, and LD livers had lower ischemic times. Recipient characteristics were similar except that mean MELD scores in LD recipients were lower (p < 0.05). With a mean follow-up of 28.3 months, 46 (90%) recipients are alive: three died from HCV recurrent liver disease and two from tumor recurrence. Based on 1-year protocol biopsies, the incidence of histologic recurrence in the three groups is as follows: WL, 81%; LD, 50% and DD split, 86% (p = 0.06 for LD versus WL). The mean grade of inflammation on the biopsy specimens was: WL, 1.31; LD, 0.33 and DD split, 1.2 (p = 0.002 for LD versus WL; p = 0.03 for LD versus DD split). Mean stage of fibrosis was: WL, 0.96; LD, 0.22 and DD split, 0.60 (p = 0.07 for LD versus WL). Liver regeneration does not seem to affect hepatitis C recurrence as much, perhaps, as factors such as DD status, donor age and cold ischemic time. [source] An In Vivo Autotransplant Model of Renal Preservation: Cold Storage Versus Machine Perfusion in the Prevention of Ischemia/Reperfusion InjuryARTIFICIAL ORGANS, Issue 7 2009Gaetano La Manna Abstract There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation. Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion (n = 6) or cold storage (n = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5,-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation. The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys. The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage. [source] Postoperative troponin I values: Insult or injury?CLINICAL CARDIOLOGY, Issue 10 2000Keith A. Horvath M.D. Abstract Background: Troponin I (TnI) is increasingly employed as a highly specific marker of acute myocardial ischemia. The value of this marker after cardiac surgery is unclear. Hypothesis: The purpose of this study was to measure serum TnI levels prospectively at 1, 6, and 72 h after elective cardiac operations. In addition, TnI levels were measured from the shed mediastinal blood at 1 and 6 h postoperatively. Serum values were correlated with cross clamp time, type of operation, incidence of perioperative myocardial infarction, as assessed by postoperative electrocardiograms (ECG) and regional wall motion, as documented by intraoperative transesophageal echocardiography (TEE). Methods: Sixty patients underwent the following types of surgery: coronary artery bypass graft (CABG) (n = 45), valve repair/replacement (n = 10), and combination valve and coronary surgery (n = 5). Myocardial protection consisted of moderate systemic hypothermia (30,32°C), cold blood cardioplegia, and topical cooling for all patients. Results: Of 60 patients, 57 (95%) had elevated TnI levels, consistent with myocardial injury, 1 h postoperatively. This incidence increased to 98% (59/60) at 6 h postoperatively. There was a positive correlation between the length of cross clamp time and initial postoperative serum TnI (r = 0.70). There was no difference in the serum TnI values whether or not surgery was for ischemic heart disease (CABG or CABG + valve versus valve). There were no postoperative myocardial infarctions as assessed by serial ECGs. There was no evidence of diminished regional wall motion by TEE. Levels of TnI in the mediastinal shed blood were greater than assay in 58% (35/60) of the patients at 1 h and in 88% (53/60) at 6 h postoperatively. Patients who received an auto-transfusion of mediastinal shed blood (n = 22) had on average a 10-fold postoperative increase in serum TnI levels between 1 and 6 h. Patients who did not receive autotransfusion average less than doubled their TnI levels over the same interval. At 72 h, TnI levels were below the initial postoperative levels but still indicative of myocardial injury. Conclusion: Postoperative TnI levels are elevated after all types of cardiac surgery. There is a strong correlation between intraoperative ischemic time and postoperative TnI level. Further elevation of TnI is significantly enhanced by reinfusion of mediastinal shed blood. Despite these postoperative increases in TnI, there was no evidence of myocardial infarction by ECG or TEE. The postoperative TnI value is even less meaningful after autotransfusion of shed mediastinal blood. [source] Progressive interstitial fibrosis of kidney allograft early after transplantation from a non-heart beating donor: possible role of persistent ischemic injuryCLINICAL TRANSPLANTATION, Issue 2010Kohsuke Masutani Masutani K, Kitada H, Yamada S, Tsuchimoto A, Noguchi H, Tsuruya K, Katafuchi R, Tanaka M, Iida M. Progressive interstitial fibrosis of kidney allograft early after transplantation from a non-heart beating donor: Possible role of persistent ischemic injury. Clin Transplant 2010: 24 (Suppl. 22): 70,74. © 2010 John Wiley & Sons A/S. Abstract:, The donor was 63-yr-old woman with subarachnoid hemorrhage. As she developed severe hypotension for more than four h before cardiac arrest, we biopsied the grafts and decided to transplant those kidneys. Recipient 1 was a 23-yr-old man on 13-yr dialysis program. After 19 d of delayed graft function (DGF), we discontinued hemodialysis (HD). However, the decrease in serum creatinine (sCr) was poor. The minimum sCr was 4.3 mg/dL on post-operative day (POD) 40, and increased to 6.5 mg/dL. The contralateral graft was transplanted to a 61-yr-old man (recipient 2) with 18-yr HD. After 15 d of DGF period, sCr decreased gradually and has been stable at 1.9 mg/dL. In recipient 1, graft biopsies performed on POD 15, 69, and 110, revealed progressive interstitial fibrosis and tubular atrophy (IF/TA) without evidences of acute rejection, tacrolimus associated injury, reflux nephropathy, or viral nephropathy. The second biopsy on POD 69 showed typical findings of acute tubular necrosis. We compared the clinical courses of the two recipients because certain features of recipient 1, such as age, duration of HD, total ischemic time, and body size were advantageous, whereas graft function was poorer than that in recipient 2. Recipient 1 developed severe anemia following the dissociation of graft function from recipient 2. In this case, posttransplant anemia and lower blood pressure might promote IF/TA through persistent ischemic tubular damage, and positive CMV antigenemia and its treatment could promote anemia. Especially in the kidney allograft from a marginal donor, we should consider various factors to obtain a better graft outcome. [source] Factors contributing to long graft survival in non-heart-beating cadaveric renal transplantation in Japan: a single-center study at Kitasato UniversityCLINICAL TRANSPLANTATION, Issue 6 2002Kazunari Yoshida Yoshida K, Endo T, Saito T, Iwamura M, Ikeda M, Kamata K, Sato K, Baba S. Factors contributing to long graft survival in non-heart-beating cadaveric renal transplantation in Japan: a single-center study at Kitasato University. Clin Transplant 2002: 16: 397,404. © Blackwell Munksgaard, 2002 A total of 107 cadaveric kidneys from non-heart-beating donors (NHBDs) have been transplanted between 1974 and 2000 at Kitasato University Hospital, Sagamihara, Japan. The patient survival of the 107 recipients of cadaveric renal transplants at 1, 5 and 10 yr was 0.857, 0.770 and 0.746, respectively. The 50% graft survival was 3.8 yr. The 5 and 10-yr graft survival was 0.457 and 0.337, respectively. Twenty of the 107 recipients of non-heart-beating cadaveric renal transplantation had graft survival longer than 10 yr. Of these 20 patients, 14 survivors still maintain functioning renal grafts and two died with functioning graft, although the remaining four reverted to dialysis because of chronic rejection and nephropathy. The average graft survival of these 20 patients at the time of study was 13.3 yr and the longest was 21.4 yr. The average serum creatinine level at 10 yr after transplantation was 1.63 mg/dL, almost identical to that at 5 yr post-transplant. The donors aged on average 40.2 yr; 13 were male and seven were female. The youngest donor was 9-yr-old and the oldest was 66. The graft survival was significantly better in the group with donor age younger than 55 yr (Log-rank: p=0.007). The average weight of the renal graft was not different between the long and shorter graft survival groups. The average warm ischemic time and total ischemic time were 9.7 and 539.7 min, respectively. The duration of post-transplant acute tubular necrosis averaged 9.2 days. These parameters tended to be shorter than those in recipients with graft survival >10 yr, but with no statistical significance. The mean numbers of acute rejection (AR) episode within 3 months after transplantation were 0.25 ± 0.66 and 0.92 ± 0.90 (p=0.020) in long survival and shorter survival groups, respectively. Long survivors had a significantly lower incidence of AR. Two of 20 cases received conventional immunosuppression with prednisolone, azathioprine and mizoribin, and 18 had prednisolone and calcineurin inhibitor (CNI). Kaplan,Meier analysis showed a significant contribution of CNI to graft survival (p=0.036). However, the graft survival reduction rate after 1 yr post-transplant did not differ between conventional and CNI immunosuppression. These data suggest that renal grafts retrieved with proper organ procurement procedures from NHBDs may survive long-term and help to overcome donor shortage. [source] Evaluation of renal function after laparoscopic partial nephrectomy with renal scintigraphy using 99mtechnetium-mercaptoacetyltriglycineINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2006KOBAYASHI YASUYUKI Aim: We evaluated the functions of an affected kidney after laparoscopic partial nephrectomy (LPN) using renal scintigraphy with 99mtechnetium-mercaptoacetyltriglycine (99mTc-MAG3). Methods: Split renal function of 10 patients who underwent LPN for renal tumors was assessed using renal scintigraphy with 99mTc-MAG3 before surgery, and 1 week and 3 months post-surgery. Results: Median operating time was 196.5 min, median tumor diameter was 2.3 cm, mean blood loss was 64 mL and mean ischemic time was 38.5 min. Median change in serum creatinine level pre- to post-surgery was 0.15 mg/dL. Median contribution of the affected kidney to total renal function (calculated using 99mTc-MAG3) was 50.0%, 41.7% and 36.1% before surgery, 1 week and 3 months after LPN, respectively. In one patient, the tumor was resected after cooling of the affected kidney with ice slush for 15 min, and the split renal function ratio remained as high as 50% at 3 months post-operatively despite a total ischemic time of 61 min. Conclusions: This paper evaluated renal function on the affected side before and after surgery by measuring split renal function with renal scintigraphy using 99mTc-MAG3. Risk factors for renal dysfunction in the affected kidney after LPN include age over 70 years with more than 30 min warm ischemic time, re-clamping of the renal artery procedure, and a warm ischemic time greater than 60 min. We believe that renal cooling with slush ice prevents renal dysfunction of the affected kidney after LPN with longer warm ischemic times. However, an easier renal cooling technique should be sought for regular use of cooling procedures in LPN. [source] Hand-assisted laparoscopic and open living donor nephrectomy in KoreaINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2005JA HYEON KU Abstract Background: We compared the results of hand-assisted laparoscopic living donor nephrectomy (LLDN) and conventional open living donor nephrectomy (OLDN). Methods: The clinical data on 49 hand-assisted LLDN and 21 OLDN on the left side performed at two institutions in Korea from January 2001 to February 2003 were reviewed. Demographic data of donors and recipients were similar in the two groups. Results: There was one conversion to an open procedure due to bleeding in the LLDN group. The median operation times (180 min in LLDN versus 170 min in OLDN) and warm ischemic times (2.5 min in LLDN versus 2.0 min in OLDN) in the two groups were similar. The estimated mean blood loss, duration of hospital stay and complication rate was also similar in the two groups. The LLDN group reported less pain (visual analog scale) postoperatively (4.1 versus 5.3), but this was not significant (P = 0.058). The time to oral intake in the LLDN group was significantly longer by an average of 1 day (P = 0.001). Return to work was sooner in the LLDN group (4.0 weeks versus 6.0 weeks; P = 0.026). The recipient graft function was equivalent between the two groups. Hand-assisted LLDN appears to be a safe and effective alternative to OLDN. Conclusion: Our findings suggest that this technique may give the ability provide grafts of similar quality to OLDN, while extending to the donors the advantages of a traditional LLDN procedure. [source] Critical ischemic time for the rat ovary: Experimental study evaluating early histopathologic changesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2009Ayhan Coskun Abstract The aim of the present study was to determine a critical ischemic time for ovary in an experimental study in rats. An experimental model using slip-knot tying of all ovarian arteries and veins in cycling female rats was developed. Rat ovaries were tied using the technique through an explorative laparotomy. Complete ischemia times of 1, 2 and 3 h were used for the study. At the end of the ischemic times, the ovaries were harvested following 1 h of reperfusion. Histology indicated a gradually increased congestion correlating with the respective increased ischemic times. According to the present findings 2 h complete ischemia yields a significant injury. The model used in the present study may be used for complete ischemia,reperfusion injury of the rat ovary. [source] Sirolimus-based immunosuppression following liver transplantation for hepatocellular carcinomaLIVER TRANSPLANTATION, Issue 5 2008Michael A. Zimmerman Experience with sirolimus (SRL)-based immunosuppression following orthotopic liver transplantation (OLT) is rapidly accumulating. In combination with calcineurin inhibitors (CNIs), SRL may reduce the incidence of acute rejection and lower overall required drug levels. This study sought to quantify long-term outcome following OLT in patients with cirrhosis and concomitant hepatocellular carcinoma (HCC) who were treated with an SRL-based regimen as a primary therapy. From January 2000 to June 2007, 97 patients underwent OLT for end-stage liver disease and HCC at the University of Colorado Health Sciences Center. Of those, 45 patients received SRL, in addition to CNIs, as a component of their primary immunosuppression regimen post-OLT. Conversely, 52 patients received the standard immunosuppression regimen including CNIs, mycophenolate mofetil, and corticosteroids. The 2 treatment groups were compared with respect to the following variables: age, gender, tumor stage by explant, grade, size, presence of vascular invasion, focality, Child's class, baseline creatinine, and warm and cold ischemic times. The 2 groups were comparable by all factors save for cold ischemic time, which was significantly longer in the CNI-treated group. Overall survival at 1 and 5 years post-OLT for patients treated with SRL was 95.5% and 78.8%, respectively. Conversely, survival in patients treated with CNIs exclusively at the same time intervals was 83% and 62%. Although there was no difference in the incidence of major complications, the SRL group experienced a modest improvement in renal function. Cumulatively, these data suggest a potential survival benefit with SRL-based therapy in patients undergoing OLT for end-stage liver disease and concomitant malignancy. Liver Transpl 2008. © 2008 AASLD. [source] Liver regeneration after adult living donor and deceased donor split-liver transplantsLIVER TRANSPLANTATION, Issue 3 2004Abhinav Humar As the number of living donor (LD) and deceased donor (DD) split-liver transplants (SLTs) have increased over the last 5 years, so too has the interest in liver regeneration after such partial-liver transplants. We looked at liver regeneration, as measured by computed tomography (CT) volumetrics, to see if there were significant differences among LDs, right-lobe LD recipients, and SLT recipients. We measured liver volume at 3 months postoperatively by using CT, and we compared the result to the patient's ideal liver volume (ILV), which was calculated using a standard equation. The study group consisted of 70 adult patients who either had donated their right lobe for LD transplants (n = 24) or had undergone a partial-liver transplant (right-lobe LD transplants, n = 24; right-lobe SLTs, n = 11; left-lobe SLTs, n = 11). DD (vs. LDs) were younger (P < 0.01), were heavier (P = 0.06), and had longer ischemic times (P < 0.01). At 3 months postoperatively, LDs had attained 78.6% of their ILV, less than the percentage for right-lobe LD recipients (103.9%; P = 0.0002), right-lobe SLT recipients (113.6%; P = 0.01), and left-lobe SLT recipients (119.7%; P = 0.0006). When liver size at the third postoperative month was compared with the liver size immediately postoperatively, LDs had a 1.85-fold increase. This was smaller than the increase seen in right-lobe LD recipients (2.08-fold), right-lobe SLT recipients (2.17-fold), and left-lobe SLT recipients (2.52-fold). In conclusion, liver regeneration, as measured by CT volume, seems to be greatest in SLT recipients. LD recipients seem to have greater liver growth than their donors. The reason for this remains unclear. (Liver Transpl 2004;10:374,378.) [source] Liver transplantation in patients with portal vein thrombosisLIVER TRANSPLANTATION, Issue 2 2001Gerardo Manzanet MD The aim of this study is to analyze the incidence, risk factors, management, and follow-up of patients with portal vein thrombosis (PVT) undergoing primary orthotopic liver transplantation (OLT). Four hundred fifteen OLTs were performed in 391 patients. In 62 patients, partial (group 1; n = 48) or complete (group 2; n = 14) PVT was found at the time of surgery. Portal flow was reestablished by venous thrombectomy. In this study, we compare 62 primary OLTs performed in patients with PVT at the time of OLT with a group of 329 primary OLTs performed in patients without PVT (group 3) and analyze the incidence of PVT, use of diagnostic methods, surgical management, and outcome. We found no significant differences among the 3 groups for length of surgery, cold and warm ischemic times, and postoperative stay in the intensive care unit. With the piggyback technique, groups 1 and 2 had greater blood losses and required more blood transfusions than group 3. The early reoperation rate was greater in group 2. The incidence of rethrombosis was 4.8% (group 1, 2%; group 2, 14.3%). Reexploration and thrombectomy (2 patients) and retransplantation (1 patient) had a 100% mortality rate. In particular, the mortality rate of patients with complete PVT with extension into the splanchnic veins is high (33%). Three-month and 4-year patient survival rates were statistically similar in the 3 groups. The presence of PVT at the time of OLT is not a contraindication for OLT. However, if PVT extends into the splanchnic veins, the outcome is guarded. [source] Safety and risk of using pediatric donor livers in adult liver transplantationLIVER TRANSPLANTATION, Issue 1 2001Sukru Emre MD Pediatric donor (PD) livers have been allocated to adult transplant recipients in certain situations despite size discrepancies. We compared data on adults (age , 19 years) who underwent primary liver transplantation using livers from either PDs (age < 13 years; n = 70) or adult donors (ADs; age , 19 years; n = 1,051). We also investigated the risk factors and effect of prolonged cholestasis on survival in the PD group. In an attempt to determine the minimal graft volume requirement, we divided the PD group into 2 subgroups based on the ratio of donor liver weight (DLW) to estimated recipient liver weight (ERLW) at 2 different cutoff values: less than 0.4 (n = 5) versus 0.4 or greater (n = 56) and less than 0.5 (n = 21) versus 0.5 or greater (n = 40). The incidence of hepatic artery thrombosis (HAT) was significantly greater in the PD group (12.9%) compared with the AD group (3.8%; P = .0003). Multivariate analysis showed that preoperative prothrombin time of 16 seconds or greater (relative risk, 3.206; P = .0115) and absence of FK506 use as a primary immunosuppressant (relative risk, 4.477; P = .0078) were independent risk factors affecting 1-year graft survival in the PD group. In the PD group, transplant recipients who developed cholestasis (total bilirubin level , 5 mg/dL on postoperative day 7) had longer warm (WITs) and cold ischemic times (CITs). Transplant recipients with a DLW/ERLW less than 0.4 had a trend toward a greater incidence of HAT (40%; P < .06), septicemia (60%), and decreased 1- and 5-year graft survival rates (40% and 20%; P = .08 and .07 v DLW/ERLW of 0.4 or greater, respectively). In conclusion, the use of PD livers for adult recipients was associated with a greater risk for developing HAT. The outcome of small-for-size grafts is more likely to be adversely affected by longer WITs and CITs. The safe limit of graft volume appeared to be a DLW/ERLW of 0.4 or greater. [source] Effects of Tisseel and FloSeal on Primary Ischemic Time in a Rat Fasciocutaneous Free Flap Model,THE LARYNGOSCOPE, Issue 2 2004Aaron W. Partsafas BS Abstract Objectives: Free flaps are the technique of choice for reconstruction of defects resulting from extirpation of tumors of the head and neck. Advances in microsurgical technique have resulted in success rates of greater than 95%. Numerous intraoperative factors, ranging from technical issues to topically applied agents, can complicate the outcome of microsurgical free tissue transfer. Synthetic tissue adhesives and hemostatic agents are playing an ever-increasing role in reconstructive surgery. The safety of these factors in free flap surgery has not been ascertained. Study Design: Animal Care Committee live rat model. Methods: Male Sprague-Dawley rats were divided into three groups: group I, Control; group 2, FloSeal; group 3, Tisseel. In each group, a 3 × 6 cm ventral fasciocutaneous groin flap based on the left superficial epigastric artery was elevated and the experimental material applied beneath the flap and around the flap pedicle prior to suturing of the flap back to the wound bed. The experimental materials consisted of 0.2 mL saline in the control group, 0.5 mL FloSeal, and 0.2 mL Tisseel. In phase I of this study, the effect of each treatment on flap survival was assessed by survival at postoperative day 4. In phase II of the study, the effects of these agents on ischemic tolerance was investigated. Five rats in each treatment group were exposed to ischemic times of 6, 8, 10, and 12 hours. Survival of the flap was assessed 7 days after reversal of the ischemia. Probit curves and the critical ischemic time (CIT50) were calculated. Results: All flaps survived the 2-hour period of ischemia and were viable at postoperative day 4. Flap survival from group 1 (Control), group 2 (FloSeal), and group 3 (Tisseel) at the various ischemic times was as follows: at 6 hours, 80%, 80%, and 80%, respectively; at 8 hours, 80%, 80%, 60%; at 10 hours, 60%, 33%, 40%; at 12 hours, 20%, 20%, 0%. The CIT50 for the Control, FloSeal, and Tisseel groups was 9.4, 9.0, and 7.0 hours, respectively. Conclusions: FloSeal, a thrombin-based hemostatic agent, and Tisseel, a fibrin glue, displayed no adverse effect on flap survival in this model. [source] Cold Machine Perfusion Versus Static Cold Storage of Kidneys Donated After Cardiac Death: A UK Multicenter Randomized Controlled TrialAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010C. J. E. Watson One third of deceased donor kidneys for transplantation in the UK are donated following cardiac death (DCD). Such kidneys have a high rate of delayed graft function (DGF) following transplantation. We conducted a multicenter, randomized controlled trial to determine whether kidney preservation using cold, pulsatile machine perfusion (MP) was superior to simple cold storage (CS) for DCD kidneys. One kidney from each DCD donor was randomly allocated to CS, the other to MP. A sequential trial design was used with the primary endpoint being DGF, defined as the necessity for dialysis within the first 7 days following transplant. The trial was stopped when data were available for 45 pairs of kidneys. There was no difference in the incidence of DGF between kidneys assigned to MP or CS (58% vs. 56%, respectively), in the context of an asystolic period of 15 min and median cold ischemic times of 13.9 h for MP and 14.3 h for CS kidneys. Renal function at 3 and 12 months was similar between groups, as was graft and patient survival. For kidneys from controlled DCD donors (with mean cold ischemic times around 14 h), MP offers no advantage over CS, which is cheaper and more straightforward. [source] Living Donor and Split-Liver Transplants in Hepatitis C Recipients: Does Liver Regeneration Increase the Risk for Recurrence?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2005Abhinav Humar Concern exists that partial liver transplants (either a living donor [LD] or deceased donor [DD] in hepatitis C virus (HCV)-positive recipients may be associated with an increased risk for recurrence. From 1999 to 2003, at our institution, 51 HCV-positive recipients underwent liver transplants: 32 whole-liver (WL) transplants, 12 LD transplants and 7 DD split transplants. Donor characteristics differed in that WL donors were older, and LD livers had lower ischemic times. Recipient characteristics were similar except that mean MELD scores in LD recipients were lower (p < 0.05). With a mean follow-up of 28.3 months, 46 (90%) recipients are alive: three died from HCV recurrent liver disease and two from tumor recurrence. Based on 1-year protocol biopsies, the incidence of histologic recurrence in the three groups is as follows: WL, 81%; LD, 50% and DD split, 86% (p = 0.06 for LD versus WL). The mean grade of inflammation on the biopsy specimens was: WL, 1.31; LD, 0.33 and DD split, 1.2 (p = 0.002 for LD versus WL; p = 0.03 for LD versus DD split). Mean stage of fibrosis was: WL, 0.96; LD, 0.22 and DD split, 0.60 (p = 0.07 for LD versus WL). Liver regeneration does not seem to affect hepatitis C recurrence as much, perhaps, as factors such as DD status, donor age and cold ischemic time. [source] |