Evaluation of apoptosis in the liver preserved by simple hypothermia using histidine-tryptophan-ketoglutarate and prolactin-modified histidine-tryptophan-ketoglutarate solution

Introduction

Organ ischemia is accompanied by cell death due to apoptosis. It occurs together with necrosis, which has more unfavorable consequences due to the release of cytokines that activate the inflammatory response cascade. The aim of this study was to assess the degree of apoptosis in porcine livers preserved by simple hypothermia for 12 hours using standard solutions (University of Wisconsin [UW] and histidine-tryptophan-glutarate [HTK]), and to evaluate the effect of prolactin (PRL) addition to the HTK solution.

Materials and methods

The study was performed on the livers of Great White breed pigs, after inducing 30 minutes of warm ischemia (WIT30), followed by 30 minutes of perfusion-cooling to 4°C, and 12 hours of preservation. Livers were evaluated after preservation in Ringer's solution (control); UW (control reference fluid); HTK and HTK modified by the addition of prolactin (20 UI/L. Apoptosis was assessed in liver sections by the TdT-mediated dUTP nick-end labeling method after 12-hour preservation. We adopted a prevalence scale ranging from 0 to 3+, depending on the number of observed nuclei and apoptotic bodies (AB).

Results

Preservation in Ringer's solution yielded AB distribution at the 1+ level, with a lack of characteristic localization resulting from necrotic lesions. Analysis of the livers preserved in the UW solution showed high, 3+ level of AB presence. For the tested HTK solution, the observed ABs localization value was 3+, whereas in the PRL-modified group it was also 3+, but with a tendency to move from zone II to cluster III, which is important for liver metabolic functions.

Conclusions

PRL improved the preservation properties of HTK for porcine livers by maintaining a high apoptosis level. It may stabilize cell membranes thus reducing the oncotic necrosis, promoting increased apoptosis during simple hypothermia.     

Adrenaline and dopamine in porcine livers after cold preservation with University of Wisconsin histidine-tryptophan-ketoglutarate, prolactin-modified histidine-tryptophan-ketoglutarate solutions

Introduction

Hepatic ischemia-reperfusion injury remains a significant factor influencing early liver graft function. The aim of this study was to assess the impact on hepatic ischemia as reflected by catecholamine concentrations of different methods of organ preservation.

Materials and methods

Catecholamine levels were measured in 24 (n = 6/group) pig livers, which underwent 30-minute warm ischemia followed by 30-minute perfusion and subsequent cold storage for 12 hours. For perfusion and preservation, we used University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK), HTK-modified with prolactin (PRL) or Ringer's solutions. Dopamine (DO) and adrenaline (ADR) concentrations in liver venous effluents were assayed using a radioimmunological method after 30 minutes of perfusion and following 12 hours of preservation.

Results

DO and ADR levels were higher after 12 hours preservation compared to 30 minutes of perfusion. HTK produced an increase of over 100%. Addition of PRL (20 IU/L) did not affect DO and ADR levels after 30 minutes of perfusion, but significantly decreased their concentrations at 12 hours of preservation. After UW perfusion and preservation, we observed a 10% increase in catecholamine levels as compared with postperfusion values. Preservation with Ringer's solution demonstrated significantly higher DO and ADR levels compared with other solutions.

Conclusion

Catecholamines are present in the liver after 30 minute of perfusion and 12 hours of cold storage. The increased levels after 12 hours of preservation may be due to their release from intracellular spaces (as a controlled process or as a result of necrosis). It may play a crucial role in reperfusion injury, which, in turn, may explain the mechanism of no-reflow phenomenon.     

Histidine-Tryptophan-Ketoglutarate and Delayed Graft Function After Prolonged Cold Ischemia

Background

Several articles have compared histidine-tryptophan-ketoglutarate solution (HTK) with other preservation solutions in both liver and kidney transplantation, and the results suggest that HTK is as good or better than the criterion standard University of Wisconsin solution (UW) for short periods of cold ischemia, such as in live donation, but that it is not so efficient for longer periods of cold ischemia, causing a higher incidence of delayed graft function.

Objective

To evaluate energy levels, metabolites, and histologic findings to determine why HTK is inefficient for longer periods of cold ischemia.

Methods

Rat livers were perfused with either HTK or UW, and at various times, tissue samples were obtained for analysis of adenine triphosphate and metabolites using high-performance liquid chromatography or for histologic analysis.

Results

The high energy charge observed with HTK-perfused livers plateaued after 5 minutes, and by 60 minutes began to decrease, following the same trend as other samples. The plateau is due to excess available glucose; however, after 1 hour, it is beginning to be consumed. Low levels of uridine, required for glycogen synthesis, are found in HTK-perfused livers, which suggests that at reperfusion, there is none available, whereas the higher concentrations found in UW-perfused livers may be advantageous after reperfusion. This will be especially detrimental to use of HTK because glycogen is used up rapidly because of the presence of α-ketoglutarate in the solution, enabling continuation of the tricarboxylic acid cycle.

Conclusions

Overall, HTK seems to do well for the first 2 hours, after which any advantage observed initially starts to disappear. A liver perfused in HTK and transplanted after more than 1 hour reacts like an organ from an individual who has been starved, because of the low energy charge and absence of a glycogen store or ability to synthesis glycogen because of lack of uridine. Livers perfused with UW demonstrate higher levels of uridine and do not lose their glycogen content to the same extent as HTK-perfused livers. These findings explain in part why HTK sometimes causes delayed graft function after longer periods of cold ischemia.     

Evaluation of cysteine effect on redox potential of porcine liver preserved by simple hypothermia

Introduction

Cysteine (cys), a thiol amino-acid, is involved in de novo glutathione (GSH) synthesis in the extra- and intracellular space. It is also probably involved in the anaerobic glycolysis process. Both these facts may affect the metabolic condition of the liver preserved by simple hypothermia for transplantation. The aim of the study was to verify whether cysteine addition to histidine-tryptophan-ketoglutarate (HTK) organ preservation solution showed a positive effect on liver redox potential after 12-hour preservation in simple hypothermia.

Materials and methods

After collecting livers of Great White breed pigs that underwent 30 min of warm ischemia, before 30-min perfusion and cooling to 4°C with modified HTK solution containing cysteine prior to 12 h of preservation. Activity of glutathione reductase (GR), glutathione peroxidase (GPx), and superoxide dismutase (SOD) was determined in liver homogenates after perfusion and after the preservation period. The results were compared with pure HTK, Ringer's and reference University of Wisconsin (UW) solutions.

Results

30 min of perfusion and 12 h of cold preservation (CIT) in the Ringer's solution markedly increased GPx, SOD, and GR activities in liver homogenates compared with the activity using other fluids. After 12-h CIT the activities of GR, GPx and SOD were significantly higher in cys-modified HTK solution than the control HTK solution. They were comparable to the values recorded for the UW group.

Conclusions

Addition of cys to the HTK solution positively influenced the total pool of free radical scavengers in a liver undergoing 12-hour ischemia in the simple hypothermia, which was reflected in the elevated redox enzyme activity possibly due to cys participation in GSH synthesis.     

Fructose 1-6 bisphosphate versus University of Wisconsin solution for rat liver preservation: does FBP prevent early mitochondrial injury?

Background

Fructose 1,6-biphosphate (FBP) has been shown to exert therapeutic effects in models of ischemia-reperfusion in organs other than the liver. This study compared FBP and University of Wisconsin (UW) solution during cold storage and reperfusion, among mitochondria of adult male Wistar rat livers.

Methods

Adult male Wistar rats were assigned to two groups according to the preservation solution used; UW or FBP Aspartate transaminase (AST), alanine transferase (ALT); and lactic dehydrogenase (LDH) were measured in samples of the storage solution obtained at 2, 4 and 6 hours of preservation. After 6 hours of cold storage, we reperfused the liver, taking blood samples to measure AST, ALT, LDH, and throbarbituric acid reactive substances (TBARS). Hepatic fragments were processed for histologic analysis; for determinations of TBARS, catalase, and nitric oxide as well as for mitochondrial evaluation by infrared spectroscopy.

Results

During cold preservation, levels of AST and LDH in the storage solution were lower among the FBP group, but after reperfusion, serum levels of AST, ALT, and LDH were higher in this group, as was catalase activity. TBARS and nitric oxide were comparable between the groups. In the UW group there was a higher amide I/amide II ratio than in the FBP group, suggesting an abnormal protein structure of the mitochondrial membrane. No signs of preservation injury were observed in any liver biopsy, but sinusoidal congestion was present in livers preserved with FBP.

Conclusion

FBP showed a protective effect for preservation during cold storage seeming to protect the mitochondrial membrane although it did not prevent reperfusion injury.     

The effect of methylprednisolone on warm ischemia-reperfusion injury in the liver

Background

Liver ischemia-reperfusion (I-R) injury is a well-known cause of morbidity and mortality following liver surgery and transplantation. Further investigation is warranted to identify measures that reduce the untoward sequelae of liver ischemia.

Methods

Male Sprague-Dawley rats (wild-type) and Zucker rats (with hepatic steatosis) were subjected to 75 minutes of 70% hepatic ischemia and 3 hours of reperfusion. The ischemic periods were based on protocols of either continuous clamping (CC) or ischemic preconditioning (IP). Prior to ischemia induction, rats were pretreated with intravenous methylprednisolone (MP; 2 mg/kg) or normal saline. Warm I-R injury was evaluated using serum levels of aspartate aminotransferase (AST), serum interleukin-6 (IL-6), and hematoxylin and eosin staining.

Results

Histology, serum IL-6, and AST release revealed that MP treatment provided significant protection as compared with ischemic controls (both CC and IP groups) only in the normal, not steatotic, livers. The inflammatory response was considerably reduced in MP groups with normal livers but not in steatotic livers. In general, the IP groups showed decreased I-R injury compared to the CC group. However, MP was able to further reduce I-R injury only in normal, not steatotic, livers.

Conclusions

MP attenuated the postischemic and inflammatory response in the normal, and not steatotic, livers. MP pretreatment might be effective in reducing warm I-R injury to livers without steatosis. The mechanism of I-R-related hepatocellular damage in steatotic liver is different than in normal liver.     

Morphine and its metabolites after patient-controlled analgesia: considerations for respiratory depression

Study Objective

To assess concentrations of morphine and its metabolites after patient-controlled analgesia (PCA).

Design

Pilot pharmacokinetic study of morphine and pharmacokinetic simulation.

Setting

Post-anesthesia care room and ward of an academic teaching hospital.

Patients

10 ASA physical status I, II, and III postoperative surgical patients.

Interventions

Patients received morphine via PCA by routine hospital protocols.

Measurements

The population mean plasma and effect-site concentrations of morphine, morphine-6-glucuronide (M6G), and morphine-3-glucuronide (M3G) was simulated in 4 patient group scenarios: morphine PCA used alone, morphine PCA used with continuous background morphine infusion of 0.5 mg/hr, morphine PCA used with continuous background morphine infusion of 1.0 mg/hr, and morphine PCA used with continuous background morphine infusion of 2.0 mg/hr.

Main Results

The 4 groups exhibited simulated peak morphine, M6G, and M3G effect-site concentrations at 8 to 24 hours post-infusion. The highest peak morphine, M6G, and M3G effect-site concentrations decreased in the following order by group: 2.0 mg/hr morphine infusion + PCA group, 1.0 mg/hr morphine infusion + PCA group, and 0.5. mg/hr morphine infusion + PCA group.

Conclusions

Patients receiving morphine PCA should be monitored closely from 8 to 24 hours postoperatively. Morphine PCA given with background infusion rates up to 1.0 mg/hr does not offer distinct pharmacokinetic advantages over morphine PCA alone. Morphine PCA with background infusion rate of 2.0 mg/hr is associated with the greatest risk of respiratory depression.     

Improved Renal Function of Warm Ischemically Damaged Kidneys Using Polysol

Objective

We sought to assess the efficacy of POLYSOL, a low-viscosity, colloid-based organ preservation solution, for the preservation of warm ischemically damaged kidney grafts compared with histidine-tryptophane-ketoglutarate (HTK) solution.

Methods

Pigs (25-30 kg) underwent a left nephrectomy after clamping the renal vessels for 30 minutes. Kidney grafts washed out with Polysol (n = 6) or HTK (n = 6) were cold stored (CS) for 20 hours at 4°C. After the preservation period, the contralateral kidney was removed and the preserved kidney implanted heterotopically. Renal function was assessed daily for 7 days. Thereafter, animals were killed and the kidney grafts removed for histologic analysis.

Results

All animals survived for 7 days. All Polysol CS-preserved grafts showed immediate function, as demonstrated by urine production within 24 hours after reperfusion as compared with 3/6 grafts in the HTK CS group. Overall, the Polysol CS group showed improved renal function compared with HTK CS. Also, peak serum creatinine and blood urea values were lower in the Polysol CS group compared with HTK-preserved grafts. Histologic evaluation of warm ischemically damaged grafts showed less glomerular shrinking, less tubular damage, less edema, less inflammatory infiltration, and less necrosis in Polysol compared with HTK-preserved grafts.

Conclusion

Application of Polysol solution for washout and CS preservation of warm ischemically damaged kidney grafts resulted in improved renal function and structural integrity when compared with HTK.     

Protective effects of clarithromycin in rats with hypoxia/reoxygenation-induced intestinal injury

Background

This study was designed to determine the role of oxidative stress, nitric oxide (NO), and glutathione-related antioxidant enzymes in rat pups with hypoxia/reoxygenation (H/R)-induced bowel injury and to evaluate the potential benefits of prophylactic clarithromycin.

Methods

One-day-old Wistar albino rat pups (N = 21) were randomly divided into 3 groups: group I (control), group II (exposed to H/R), and group III (clarithromycin + H/R). Clarithromycin was administered (40 mg/kg) subcutaneously to group III for 3 days. On the fourth day, all rats except controls were exposed to H/R and were killed at 6 hours after H/R. Histopathologic injury scores (HIS), malonyldialdehyde, glutathione (GSH), glutathione-peroxidase (GSH-Px) activities, and NO levels were measured on intestinal samples.

Results

Whereas there was no difference for malonyldialdehyde levels among groups, HIS and NO levels were higher in group II than groups I and III (P < .05). However, GSH and GSH-Px activities were lower in group II than groups I and III (P < .05). Clarithromycin significantly increased GSH and GSH-Px activities and reduced HIS and NO levels in group III.

Conclusion

This study showed that oxidative stress and NO contributed to the pathogenesis of H/R-induced bowel injury and that clarithromycin had a protective effect on bowel injury owing to anti-inflammatory and antioxidant effects.     

Laparoscopy-assisted orchiopexy for recurrent undescended testes in children

Objective

Reoperative orchidopexy is a technical challenge to pediatric surgeons. The laparoscopy-assisted procedure is described for securing the testis in the scrotum in patients with a past history of open orchidopexy and testes in an unsatisfactory position.

Patients and Methods

Thirty-one patients with 35 abnormally positioned testes (4 bilateral) were evaluated. All patients had a past history of inguinal surgery, and ages ranged between 2.5 and 13 years (mean, 5.5 years). Previous surgical procedures included 32 orchiopexies and 3 testicular detorsion of undescended testis. If needed, inguinal dissection was performed to loose the adherence between the cord and inguinal canal. Laparoscopic orchidopexy was applied to allow the testis to remain in the scrotum without tension. Patients underwent follow-up every 3 months after the operation with physical and ultrasound examinations.

Results

Ten low inguinal testes were treated directly with open inguinal redo orchidopexy, whereas laparoscopy-assisted orchidopexy was possible in 23 (92%) of the remaining 25 reoperations. In 2 (8%) of these cases, severe scarring was present between the cord and the inguinal canal impeding the laparoscopy-assisted orchidopexy. For laparoscopy-assisted procedure, the operation time was 42 to 67 minutes (mean = 52 min). After the laparoscopy-assisted reoperations, 23 (92%) testes remain within the scrotum after a mean follow-up of 22 months (range, 6-32 months).

Conclusion

When feasible, laparoscopy-assisted orchiopexy is a simple and effective technique for securing testicles in reoperative orchiopexy procedures.     

Comparative analysis of the performance of various crystalloid cardioplegic solutions on myocardial protection after prolonged cold ischemia

Introduction

The quality and effectiveness of myocardial protection are fundamental problems to expand the use of and consequently good outcomes of donated hearts for transplantation.

Objective

The purpose of this investigation was to compare the cardioprotective effects of Krebs-Henseleit, Bretschneider-HTK, St Thomas, and Celsior solutions using a modified nonrecirculating Langendorff column model of isolated perfused rat heart during prolonged cold storage.

Materials and Methods

After removal 36 rat hearts underwent isolated perfusion into a Langendorff apparatus using Krebs-Henseleit solution for a 15-minute period of recovery; we excluded organs that did not maintain an aortic pressure above 100 m Hg. Subsequently, we equally distributed the hearts into four groups according to the cardioprotection solution; group 1, Krebs-Henseleit (control); group II, Bretschneider-HTK; group III, St Thomas; and group IV, Celsior. Each heart received the specific cardioplegic solution at 10°C for 2-hour storage at 20°C, before a 15 minutes perfusion with Krebs-Henseleit solution for recovery and stabilization. After 60 additional minutes of perfusion, every 5 minutes we determined heart rate (HR), coronary flow (CF), left ventricular systolic pressure (LVSP), and positive and negative peak of the first derivative of left ventricular pressure (+dP/dt and −dP/dt, respectively).

Results

Comparative analysis by Turkey's test showed the following performances among the groups at 60 minutes of reperfusion: HR: II = IV > III > I; CF: II = IV > I = III; LVSP: IV > I = II = III; +dP/dt: IV > I = II = III; and −dP/dt: IV = II > I = II.

Conclusion

Cardioprotective solutions generally used in clinical practice are not able to avoid hemodynamic alterations in hearts exposed to prolonged ischemia. Celsior solution showed better performance than Bretschneider-HTK, St Thomas, and Krebs-Henseleit.     

Recombinant Human Erythropoietin Pretreatment Attenuates Heart Ischemia-Reperfusion Injury in Rats by Suppressing the Systemic Inflammatory Response

Background

Ischemia-reperfusion (I/R) injury may influence graft function after transplantation. Erythropoietin (EPO) attenuates I/R injury in various animal organs such as intestine, brain, and kidney.

Objective

To evaluate the effects of pretreatment with recombinant human EPO (rhEPO) on I/R-induced heart injury.

Materials and Methods

A rat model of I/R injury was established by ligating the left descending coronary artery for 30 minutes, followed by reperfusion for 4 hours. Fifty Sprague-Dawley rats were divided into 5 groups: sham operation; I/R; I/R+rhEPO, 100 U/kg; I/R+rhEPO, 1000 U/kg; and I/R+rhEPO, 5000 U/kg. Electrocardiograms were assessed continuously to note arrhythmia caused by reperfusion. Serum concentrations of interleukin (IL)-6 and IL-8, and tumor necrosis factor-α were measured at 2 and 4 hours after reperfusion.

Results

The rhEPO-treated animals exhibited dosage-dependent significant reduction in the incidence of ventricular arrhythmia caused by reperfusion, and markedly decreased serum concentrations of IL-6, IL-8, and tumor necrosis factor-α (P < .05) compared with the I/R group (P < .05).

Conclusion

The rhEPO attenuates myocardial I/R injury in rats, at least in part related to inhibition of the system inflammatory response.     

Maternal microchimerism in biliary atresia

Background

The aim of this study was to determine the existence and extent of maternal microchimerism in the livers of biliary atresia (BA) patients.

Methods

Two series of investigations were performed based on the sex of our subjects. Subjects for series I were men, of which 6 had BA. Livers were analyzed using X and Y chromosome probes and fluorescent in situ hybridization. Subjects for series II were woman. Nine BA cases and their mothers were HLA typed (class I). Daughter livers were also tested for antibodies to maternal and other HLA. Two cases of neonatal hepatitis, 2 cases of Alagille syndrome, and 1 case of Byler syndrome acted as controls.

Results

All male BA livers were found to contain a mixture of cells with 1 and 2 X chromosomes (ie, XY or XX). All livers from male controls had only 1 X chromosome (ie, XY). All female BA subjects had varying intensities of antimaternal HLA class I (HLA-A) antibodies in their bile duct epithelium and hepatocytes (strong, 5; mild, 3; weak, 1). The liver from the female control did not display any antimaternal HLA class I antibodies (HLA-Ab).

Conclusion

Our preliminary data appear to show that maternal microchimerism is present within the livers of patients with progressive postnatal type BA. We suggest that BA could in fact be a graft-vs-host disease masquerading as an autoimmune reaction triggered by maternal microchimerism, and we intend to pursue this hypothesis further to clarify the etiology of BA.     

Hepatocyte viability and adenosine triphosphate content decrease linearly over time during conventional cold storage of rat liver grafts

Introduction

The gold standard in organ preservation is static cold storage (SCS) using University of Wisconsin solution (UW). Although it is well-known that there is a finite limit to SCS preservation, and that there is a correlation between the adenosine triphosphate (ATP) levels and organ function post-preservation, a quantitative relationship has not been established, which is important in understanding the fundamental limitations to preservation, minimizing cold ischemic injury, and hence maximizing use of the donor organ pool.

Aim

This study determines the time limits of cellular viability and metabolic function during SCS, and characterizes the relationship between cellular viability and energetic state using clinically relevant techniques in organ preservation.

Methods

Rat livers were procured and stored using conventional storage in UW solution at 4°C. Viability was assessed by determining the amount of viable hepatocytes and intracellular ATP content after 0, 24, 48, 72, and 120 hours of storage.

Results

Numbers of viable hepatocytes that were isolated from these livers decreased steadily during SCS. After 5 days, viable hepatocytes decreased from 25.95 × 10⁶ to 0.87 × 10⁶ cells/gram tissue. Intracellular ATP content decreased from 9.63 to 0.93 moles/g tissue. Statistical analysis of variance established a linear relation for both parameters as a function of time (P < .05).

Conclusion

The linear correlation between hepatocyte viability, ATP content, and storage time suggests a shared physiological foundation. These findings confirm ATP as direct predictor for organ quality in the context of liver preservation, which will aid quantitative assessment of donor organs for various applications.     

Intrahepatic Biliary Anatomy Derived From Right Graft Adult Live Donor Liver Transplantation

Objective

The successful management of the bile duct in right graft adult live donor liver transplantation requires knowledge of both its central (hilar) and distal (sectorial) anatomy. The purpose of this study was to provide a systematic classification of its branching patterns to enhance clinical decision-making.

Patients and Methods

We analyzed three-dimensional computed tomography (3-D CT) imaging reconstructions of 139 potential live liver donors evaluated at our institution between January 2003 and June 2007.

Results

Fifty-four (n = 54 or 38.8%) donor candidates had a normal (classic) hilar and sectorial right bile duct anatomy (type I). Seventy-eight (n = 78 or 56.1%) cases had either hilar or sectorial branching abnormalities (types II or III). Seven (n = 7 or 5.1%) livers had a mixed type (IV) of a rare and complex central and distal anatomy.

Conclusions

We believe that the classification proposed herein can aid in the better organization and categorization of the variants encountered within the right-sided intrahepatic biliary system.     

Comparing the performance of rat lungs preserved for 6 or 12 hours after perfusion with low-potassium dextran or histidine-tryptophan-ketoglutarate

Introduction

In lung transplantation, graft dysfunction is a frequent cause of mortality; the etiopathogenesis is related to ischemia-reperfusion injury. We sought to compare the lung performance of rats after reperfusion after presentation with 3 solutions at 2 ischemia times.

Methods

We randomized 60 male Wistar rats to undergo anterograde perfusion via the pulmonary artery with low-potassium dextran (LPD), histidine-tryptophan ketoglutarate (HTK), or saline. After extraction, the heart-lung blocks were preserved in a solution at hypothermia for 6 or 12 hours before perfusion with homologous blood for 60 minutes using ex vivo system Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus). Respiratory mechanics, pulmonary weight, pulmonary artery pressure (PAP), and relative lung oxygenation capacity (ROC) measurements were obtained every 10 minutes.

Results

Comparing tidal volume (TV), compliance, resistance, ROC, PAP, and pulmonary weight the LPD, HTK, and saline group did not differ at 6 and 12 hours. The TV was higher in the lungs with 6-hour ischemia in the LPD, HTK, and saline groups. Compliance was higher in the lungs with 6-hour ischemia in the LPD and saline groups. There were no differences in ROC values comparing lungs with 6- versus 12-hour ischemia in the LPD group. A significant difference was observed between lungs in the HTK and saline groups. Resistance was higher in the lungs with 12-hour ischemia among the LPD, HTK, and saline groups. There was a gradual weight increase in the lungs, particularly those undergoing 12-hour ischemia, despite the absence of a significant difference between groups.

Conclusion

Rat lungs perfused with LPD and HTK preservation solutions showed similar reperfusion performances in this ex-vivo perfusion model.     

External validation of postoperative nomograms for prediction of all-cause mortality, cancer-specific mortality, and recurrence in patients with urothelial carcinoma of the bladder

Background

The Bladder Cancer Research Consortium (BCRC) created nomograms to predict all-cause mortality (ACM), cancer-specific mortality (CSM), and recurrence after radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB).

Objective

To perform a formal validation of the BCRC nomograms in a large multi-institutional patient cohort from Europe.

Design, setting, and participants

Records of 2501 patients who underwent RC for UCB at eight European centers were reviewed. Complete information for external validation was available in 2404 patients for the ACM and CSM nomograms and in 2243 patients for the recurrence nomogram.

Measurements

For the purpose of external validation, model discrimination was measured using the receiver operating characteristics derived area under the curve. Calibration plots examined the relationship between predicted and observed probabilities at 2 yr, 5 yr, and 8 yr. Decision curve analyses were applied to assess the net benefit derived from the three models.

Results and limitations

The discrimination accuracies of the BCRC nomograms for ACM and CSM at 2 yr, 5 yr, and 8 yr after RC were 71.0%, 69.1%, and 68.2%, and 74.9%, 73.1%, and 72.4%, respectively. The accuracy of discrimination for the recurrence nomogram at the same time points was 76.5%, 75.3%, and 74.9%, respectively. Calibration plots revealed slight underestimations from ideal predictions. Decision curve analyses showed an increased net benefit for the use of the BCRC nomograms in this cohort. Limitations include the retrospective study design, potential surgeon bias, and lack of a central pathologic review.

Conclusions

The ACM, CSM, and recurrence nomograms showed acceptable predictive accuracies and could thus be adopted into clinical practice in UCB patients treated in Europe.     

Effect of university of wisconsin and histidine-tryptophan-ketoglutarate preservation solutions on blood potassium levels of patients undergoing living-donor liver transplantation

Background

The potassium content of University of Wisconsin solution (UW) is 125 mEq/L and that of histidine-tryptophan-ketoglutarate solution (HTK) only 9 mEq/L. The aim of the present study was to analyze their effects to change potassium levels on reperfusion among patients undergoing living-donor liver transplantation.

Methods

Anesthesia records of adult living-donor liver transplant patients were reviewed retrospectively. Patients received liver graft preserved in UW were grouped in group I (GI) and HTK in group II (GII). The potassium levels in the anheptic phase were compared with those 5 minutes after reperfusion using paired Student t tests. P values of <.05 were regarded to be significant.

Results

Eighty-five GI patients showed the potassium significantly decreased from 3.76 ± 0.70 to 3.60 ± 0.74, whereas the change among 355 GII patients was almost unremarkable: 4.00 ± 0.57 to 3.96 ± 0.06 mEq/L.

Conclusions

Although UW contains a higher potassium content, it seems to have no negative impact on changes in serum potassium levels; in contrast it decreased the potassium level significantly at 5 minutes after reperfusion. Both preservation solutions maintain the patients' potassium levels within the normal range.     

Operative vs nonoperative management of blunt pancreatic trauma in children

Purpose

The aim of this study was to evaluate the outcome of nonoperative vs operative management of blunt pancreatic trauma in children.

Methods

Retrospective review of pancreatic injuries from 1995 to 2006 at an urban level I regional pediatric trauma center.

Results

Forty-three children with pancreatic injury were included in the analysis. Injuries included grade I (n = 18), grade II (n = 6), grade III (n = 17), and grade IV (n = 2). For grade II to IV injuries, patients managed operatively (n = 14) and nonoperatively (n = 11) had similar lengths of stay and rates of readmission, despite increased pancreatic complications (PCs) in the nonoperative cohort (21% vs 73%; P = .02). There was a trend toward increased non-PCs in patients managed with resection (P = .07). Twelve patients underwent successful diagnostic endoscopic retrograde cholangiopancreatography in which duct injury was identified. In this group, nonoperative management was pursued in 6 patients but was associated with increased rates of PC (86% nonoperative vs 29% operative; P = .02).

Conclusions

Operative management of children with grades II to IV pancreatic injury results in significantly decreased rates of PCs but fails to decrease length of stay in the hospital, possibly as a result of non-PCs. Endoscopic retrograde cholangiopancreatography may serve as a useful diagnostic modality for guiding operative vs nonoperative management decisions.     

Recombinant human soluble thrombomodulin (ART-123) prevents warm ischemia-reperfusion injury in liver grafts from non-heart-beating donors

Background

Liver transplantation is an established treatment for end-stage liver disease. However, an ongoing problem worldwide concerning this treatment is the shortage of grafts. Although transplantation using grafts from non-heart-beating donors (NHBDs) is considered a promising solution, some researchers have reported that these liver grafts are associated with primary graft nonfunction and biliary complications. The purpose of this study was to establish a safe technique procuring liver grafts from marginal donors such as NHBDs.

Materials and methods

Male Wistar rats were divided into three groups: (1) the heart-beating (HB) group, whose livers were retrieved from HB donors; (2) the non-HB (NHB) group, whose livers were retrieved from NHBDs that had experienced an apnea-induced agonal condition (for this group, livers were subjected to warm ischemia for 30 minutes after cardiac arrest); and (3) the recombinant human soluble thrombomodulin (ART-123) group, whose livers were retrieved in the same manner as the NHB group but pretreated with ART-123 (1 mg/kg) at the agonal stage. The livers were reperfused for 60 minutes with oxygenated Krebs-Henseleit bicarbonate buffer after cold preservation for 6 hours.

Results

Bile production and portal flow volume in the ART-123 group were significantly higher than those in the NHB group. Alanine aminotransferase levels in the ART-123 group were significantly lower than those in the NHB group. Histological findings showed the narrowing of sinusoidal spaces and necroses in the NHB group were more severe than those in the ART-123 group.

Conclusions

These results suggest that thrombomodulin may improve the viability of liver grafts from NHBDs.