[Surgical risk scale in pediatric surgery]. / Escala de riesgo quirúrgico en cirugía pediátrica.

INTRODUCTION: The need to measure the level of surgical risk arises from its direct relationship with the development of postoperative complications and the use of hospital resources. The construction of a surgical risk scale (ERQ) for pediatric surgery should be based on a common language, by using a small number of easy to collect and reproduce variables. The objectives of this study were to construct an ERQ for pediatric patients and to analyze the surgical performance. MATERIALS AND METHODS: We retrospectively analyzed 105 primary surgical procedures under general anesthesia performed by liver transplantation service at Hospital Garrahan, between 29/6/08 and 25/3/10. Newborn patients were not considered. The ERQ was built by adding patient risk factors (PRL): weight (< o > 10 kg), co-morbidities (coagulopathy-obesity-diabetes) and life support; and the magnitude level of the surgical procedure (SPL): surgical time and requirement of blood transfusions. The surgical performance was considered as a relation between the level of surgical risk and the post-operative results, measured with the classification of surgical complications proposed by Clavien et al (STROC). The main end point of the study was the STROC > or = 3 (severe complications). The ERQ predictive power for serious complications was compared with the anaesthetic risk (ASA). Descriptive and analytical statistics took place. The predictive value for complications was calculated by means of a ROC curve. The estimation of the risk was calculated by relative risk. RESULTS: The ERQ was constituted on a continuum of 6 risk levels (2 to 7). The ROC's curve predictive power to determine the development of severe post-operative complications (STROC > or = 3) was 0.87 (CI 0,80-0,94) for the ERQ and 0.81 (CI 0,73-0,89) for the ASA. Level of > or = 5 of ERQ was the cut-off point that better predicted the development of STROC > or = 3. CONCLUSION: The ERQ is an easy tool, useful to quantify and compare surgical risks and results. It showed a high predictive power of postoperative complications.

Model for end-stage liver disease-based allocation system for liver transplantation in Argentina: does it work outside the United States?

BACKGROUND: In July 2005, Argentina was the first country after the United States to adopt the MELD system. The purpose of the present study was to analyse the impact of this new system on the adult liver waiting list (WL). METHODS: Between 2005 and 2009, 1773 adult patients were listed for liver transplantation: 150 emergencies and 1623 electives. Elective patients were categorized using the MELD system. A prospective database was used to analyse mortality and probability to be transplanted (PTBT) on the WL. RESULTS: The waiting time increased inversely with the MELD score and PTBT positively correlated with MELD score. With scores >/= 18 the PTBT remained over 50%. However, the largest MELD subgroup with <10 points (n = 433) had the lower PTBT (3%). In contrast, patients with T(2) hepatocellular carcinoma benefited excessively with the highest PTBT (84.2%) and the lowest mortality rate (5.4%). The WL mortality increased after MELD adoption (10% vs. 14.8% vs. P < 0.01). Patients with <10 MELD points had >fourfold probability of dying on the WL than PTBT (14.3% vs. 3%; P < 0.0001). CONCLUSIONS: After MELD implementation, WL mortality increased and most patients who died had a low MELD score. A comprehensive revision of the MELD system must be performed to include cultural and socio-economical variables that could affect each country individually.

Characteristics of Liver Transplantation in Argentina: A Multicenter Study.

INTRODUCTION: There is a lack of information regarding outcomes after liver transplant in Latin America. OBJECTIVES: This study sought to describe outcomes after liver transplant in adult patients from Argentina. METHODS: We performed an ambispective cohort study of adult patients transplanted between June 2010 and October 2012 in 6 centers from Argentina. Only patients who survived after the first 48 hours postransplantation were included. Pretransplantation and posttransplantation data were collected. RESULTS: A total of 200 patients were included in the study. Median age at time of transplant was 50 (interquartile range [IQR] 26 to 54) years. In total, 173 (86%) patients had cirrhosis, and the most frequent etiology in these patients was hepatitis C (32%). A total of 35 (17%) patients were transplanted with hepatocellular carcinoma. In patients with cirrhosis, the median Model for End-Stage Liver Disease (MELD) score at time of liver transplant was 25 (IQR 19 to 30). Median time on the waiting list for elective patients was 101 (IQR 27 to 295) days, and 3 (IQR 2 to 4) days for urgent patients. Almost 40% of the patients were readmitted during the first 6 months after liver transplant. Acute rejection occurred in 27% of the patients. Biliary and vascular complications were reported in 39 (19%) and 19 (9%) patients, respectively. Renal failure, diabetes, and dyslipidemia were present in 40 (26%), 87 (57%), and 77 (50%) at 2 years, respectively. CONCLUSIONS: We believe the information contained in this article might be of value for reviewing current practices and developing local policies.

Combined cardiohepatic transplantation due to severe heterozygous familiar hypercholesteremia type II: first case in Argentina--a case report.

Heterozygous familial hypercholesteremia type II is a recessive autonomic disease with a population incidence

The UW solution for canine kidney preservation. Its specific effect on renal hemodynamics and microvasculature.

The preservation effects of UW solution on renal hemodynamics and microvascular systems were studied in canine kidney autografts. In 72-hr UW-preserved kidneys, the microvessels of both cortex and medulla were completely visualized with silicon rubber compound 1 hr after reperfusion. Histology also showed extremely well-preserved arterioglomerular and tubular systems. These results were correlated with good renal blood flow, prompt recovery of posttransplant graft function, and 100% two-week survival of dogs. In contrast, kidneys preserved for 72 hr with Euro-Collins solution showed necrotic and obstructive changes of the microvasculature and deterioration of renal hemodynamics. In 120-hr UW-preserved kidneys, the microcirculation of the medullary region became poor after reflow when there was fairly intact perfusion of the cortical region, indicating an ischemia-related intrarenal blood flow maldistribution. The 120-hr kidneys subsequently failed in spite of having a good blood flow and morphologically well-maintained microvasculature after reperfusion. These data demonstrated that much, but not all, of the beneficial effect of UW solution in kidney preservation might be attributed to its remarkable protection of renal microvasculature. Correction of intrarenal blood maldistribution caused by a discrepancy in tolerance to ischemia of the vascular and tubular systems might be important in successfully preserving the kidney for 120 hr.

Effect of cold ischemia time on the early outcome of human hepatic allografts preserved with UW solution.

Five hundred ninety-three cadaveric livers were used for primary liver transplantation between October 24, 1987, and May 19, 1989. The grafts were procured with a combined method, using in situ cooling with cold electrolyte solution and backtable flushing with UW solution. The mean cold-ischemia time was 12.8 (range 2.4-34.7) hr. The cases were divided into 5 groups according to the cold-ischemia time: group 1: less than 10 hr (n = 223); group 2: 10-14 hr (n = 188); group 3: 15-19 hr (n = 101); group 4: 20-24 hr (n = 52); and group 5: greater than or equal to 25 hr (n = 29). There was no difference between the 5 groups in 1-year patient survival, highest SGOT in first week after operation, and SGOT and total bilirubin during the first month after operation. However, with a logistic regression model, the retransplantation rate (P = 0.001) and primary nonfunction rate (P = 0.006) significantly rose as cold-ischemia time increased, meaning that the equivalency of patient survival was increasingly dependent on aggressive retransplantation.

The effect of bile duct ligation and bile diversion on FK506 pharmacokinetics in dogs.

Mongrel or beagle dogs were submitted to bile duct ligation, or to extraenteric biliary diversion by means of choledochoureterostomy. The kinetics of intravenously administered FK506 was not changed from control status two weeks after bile duct ligation, but the bioavailability of orally administered FK506 was nearly quadrupled. Following oral administration, the absorption of FK506 was highly variable. The results indicate that in dogs FK506 is absorbed from the intestine just as efficiently in the absence of enteric bile and in presence of exogenous bile salt supplement when compared with its absorption in presence of normal bile drainage. These findings with FK506 are different from those with cyclosporine after biliary obstruction or diversion and will have important practical as well as experimental ramifications.

Liver transplantation in transthyretin familial amyloid polyneuropathy: first report from Argentina.

This is the first report from Argentina of liver transplantation in patients with transthyretin related familial amyloidotic polyneuropathy. The aims of the study were to analyze the clinical characteristics of this new focus and evaluate the postoperative complications and long term follow up. Five of ten patients evaluated underwent liver transplantation. During the waiting period the polyneuropathy disability score in each patient progressed one or two stages. Pretransplant modified body mass index was 723. The procedure was done with full size grafts in four cases and a split right graft in one. All patients presented postoperative complications related to disease: severe edema of the legs, recurrent choledochal lithiasis, postoperative hernia, necrotizing fasciitis and ischemic rectosigmoidal perforation. Assessment of three patients after 20 months of transplantation showed improvement in somatic and mental symptoms. No improvement was noted in cardiac denervation and gastric stasis. Liver transplantation is a rational therapeutic option for transthyretin familial amyloidotic polyneuropathy in Argentina and should be indicated in earlier stages of the symptomatic disease to reduce the postoperative morbidity and mortality. Family studies and follow up of asymptomatic carriers will define the epidemiological behavior in this country and facilitate early therapeutic intervention.

Renal transplantation in baboons under FK 506.

FK 506 was tested in unrelated baboons submitted to renal transplantation and bilateral native nephrectomy. Untreated baboons died after 9.2 +/- 4.0 SD days. When FK 506 was given orally for 90 days, survival with the optimum dose was 74.6 +/- 28.9 days; this allowed maximum credit for each individual animal of 90 days. A 3-day course of intramuscular FK 506 started on postoperative day 4 allowed 1- to 2-month survival. Delayed rejection in these baboons as well as in those treated daily for 90 days with FK could sometimes be reversed temporarily with a second 3-day course. The doses required for a good therapeutic effect were 10 times greater in baboons than in dogs, a finding that may reflect a species difference of lymphocyte sensitivity to this drug. FK appeared to be relatively nontoxic in subhuman primates, and it remains a promising drug for clinical trial.

Immunosuppression of canine, monkey, and baboon allografts by FK 506: with special reference to synergism with other drugs and to tolerance induction.

In dogs the most effective oral dose of FK 506 for prevention of renal homograft rejection was 1.5 mg/kg/day. With maximum credit allowed at 90 days, survival was increased to 61.0 +/- 33.6 (SD) days compared with 13.0 +/- 4.1 in untreated control animals. Higher doses were toxic. The smallest dose that was used (0.5 mg/kg/day) prolonged survival after renal transplantation to 33.7 +/- 23.9 (SD) days. When the small dose of FK 506 was combined with 5 mg/kg/day of cyclosporine and 5 mg of prednisone, five of six canine kidney recipients lived for 90 days. These results were degraded by omission of any of the constituent drugs or reduction by half of the triple drug doses. Thirteen of the dogs treated with various drug regimens lived for 90 days, after which time treatment was stopped; 10 of the dogs eventually rejected the grafts, but three had continued graft function for 6 months or longer and may be permanently tolerant. Moreover, in dogs when 1 mg/kg of intramuscular FK was given to 19 kidney and seven liver recipients for 3 days on postoperative days 1 to 3, 4 to 6, or 7 to 9, the animals survived subsequently for 11 to more than 160 days. All but four of the grafts were eventually rejected, but the prolonged effect of a short course of delayed therapy suggests the possibility of tolerance induction. In cynomolgus monkeys and baboons, FK as a single drug was found to be immunosuppressive after kidney transplantation. Correlation in the dogs and primates between immunosuppression, toxicity, and FK blood levels was not possible because of presently imperfect standardization of assay and monitoring techniques. FK had serious side effects in dogs, but not so obviously in monkeys and not at all in baboons.

Comparison of UW with other solutions for liver preservation in dogs.

The efficacy of the University of Wisconsin (UW) solution was compared with conventional Euro-Collins solution, as well as with 3 variants of a silica gel solution developed at the University of Minnesota (UM). Protection of the liver grafts with UW was superior after 24 hour preservation, although the results were inferior to those with immediate transplantation, as judged by animal survival, liver function tests, coagulation, and histopathologic parameters. The UM-III solution allowed similar animal survival as with the UW solution. Lactobionate and raffinose that are contained in both the UW and UM-III solutions were thought to be essential constituents for long-term preservation of liver grafts. The study not only establishes, under controlled circumstances, the superiority of the UW solution, but it also provides insight about the reasons for its effectiveness as well as a caution against its over exploitation.

Tube choledochoureterostomy: a simple method for bile diversion.

A technique of bile diversion by tube choledochoureterostomy has been devised for the purpose of studying the role of bile in the intestinal absorption of drugs. This method was used in six dogs. No technical difficulties or major complications developed, as are inevitable with alternative methods, including external fistula.

Effect of FK506 in experimental organ transplantation.

FK506 is the most potent immunosuppressive agent known. Its toxicity is substantial in dogs, minor in rats, and unknown in subhuman primates. In small doses that are nontoxic even in dogs, it can be used in synergistic combination with cyclosporine, steroids, and presumably in other drugs.

Canine kidney transplantation with FK-506 alone or in combination with cyclosporine and steroids.

The immunosuppressive agent FK permitted increased kidney transplant survival in dogs over a wide dose range, but with weight loss and manifold evidence of toxicity. The best use of FK at low doses was in combination with CyA and Pred.

Orthotopic liver transplantation in dogs receiving FK-506.

Ten dogs that survived the perioperative events of liver transplantation were treated with 1 mg/kg/d oral FK. Eight of the recipients lived for at least 1 month postoperatively, and seven are still alive with normal hepatic function after 35 to 65 days. The consistency and good quality of results with this difficult transplant preparation using FK, in spite of its rumored great toxicity in dogs, have highlighted the importance of further developing the drug.

[Autoimmune hepatitis in children. Initial presentation as fulminant hepatic failure]. / Hepatitis autoinmune en niños. Presentación inicial como falla hepática fulminante.

UNLABELLED: There are few cases reported of autoimmune hepatitis (AIH) type 2 presenting as fulminant hepatic failure (FHF) in children. The purpose of this study was to report three girls with AIH type 2 that presented as FHF. METHODS: Over a period of 12 years, 123 patients with AIH diagnosed based on international criteria, 9 (7%) were type 2.3 of them presented as FHF. Other etiologies (viral, metabolic and toxic) were ruled out. The treatment was started with prednisone (2 mg-kg-day) and azathioprine (2 mg-kg-day). EVOLUTION: Patients 1 and 3 died while waiting for liver transplant (LT) at 72 and 48 hours after initiating medical treatment. Patient 2 underwent LT3 days after starting treatment, with excellent evolution at 3 years and 7 months of follow up. CONCLUSIONS: 1--AIH type 2 was very infrequent in our group. 2--33% of cases had initial presentation as FHF. 3--The course of the disease was aggressive, not responding to immunosuppressive therapy. The evolution was unfavorable in all patients. 4--LT is an alternative treatment for this severe disease.

[Pharmacovigilance of calcineurin inhibitor in peidatric kidney and liver transplantation]. / Farmacovigilancia de inhibidores de calcineurina en trasplante renal y hepático pediátrico.

AIM: To develop a pharmacovigilance program of calcineurin inhibitors used in pediatric renal and liver transplant patients at Hospital de Pediatría JP Garrahan, Argentina. METHODS: Adverse drug reactions (ADRs) of pediatric patients with kidney and liver transplantation treated with calcineurin inhibitors (cyclosporine and tacrolimus) were evaluated by retrospective review of medical records of patients transplanted between 2010 and 2011. In addition, we carried out active pharmacovigilance since March, 2011. ADRs were reported to the National Health Authority. RESULTS: A total of 59 patients, 28 kidney transplant and 31 liver tarnsplant patients were analyzed. In both transplants, 60 ADRs to cyclosporine were reported including (number of cases), hypertension (19) and nephrotoxicity (6). In addition, 46 ADRs to tacrolimus were registered as hypomagnesemia (25), hypertension (7) and nephrotoxicity (5). A total of 95% and 96% of the adverse events to cyclosporine and tacrolimus, respectively, were defined as probable or definitive. Lastly, 70% and 98% of the events to cyclosporine and tacrolimus respectively, have been moderately severe or severe. CONCLUSIONS: This is the first study in Latin America that developed an intensive qualitative and quantitative analysis of the ADRs to calcineruin inhibitors in pediatric kidney and liver transplant patients. Spontaneous reporting should be motivated as well as monitoring ADRs should continue in the medium and long term for improving patient's quality of life.

Objetivo: Desarrollar un programa de farmacovigilancia de pacientes pediátricos trasplantados hepáticos y renales centrado en inmunosupresores calcineurínicos del Hospital de Pediatría JP Garrahan de Argentina. Métodos: Se evaluaron las reacciones adversas a medicamentos (RAM) de los pacientes pediátricos trasplantados renales y hepáticos de nuestro hospital tratados con inhibidores de calcineurina (ciclosporina y tacrolimus) por revisión retrospectiva de historias clínicas de pacientes trasplantados en 2010-2011, y análisis prospectivo por farmacovigilancia activa de trasplantados fuera de dicho período, cuyas complicaciones se hayan presentado en los ateneos semanales del Servicio de Trasplante desde marzo de 2011. Las RAM se notificaron a la autoridad sanitaria nacional. Resultados: Se analizaron un total de 59 pacientes, 28 trasplantados renales y 31 hepáticos. Se notificaron, en ambos trasplantes, 60 RAM a ciclosporina destacándose (número de casos) hipertensión arterial (19) y nefrotoxicidad (6). Asimismo, se registraron 46 RAM a tacrolimus, incluyendo hipomagnesemia (25), hipertensión (7) y nefrotoxicidad (5). El 95% y 96% de los eventos adversos a ciclosporina y a tacrolimus, respectivamente, han sido agrupados como probables o definitivos. El 70% y 98% de los eventos adversos a ciclosporina y a tacrolimus respectivamente, han sido de severidad moderada o grave. Conclusiones: Este es el primer proyecto en América Latina que propone y desarrolla el estudio cuali-cuantitativo intensivo de RAM a inhibidores de calcineurina en trasplante pediátrico renal y hepático. Es necesario estimular la notificación espontánea así como continuar el seguimiento de RAM a mediano y largo plazo para mejorar la calidad de vida del paciente trasplantado.

Monitoring cyclosporine microemulsion at two hours post dosing in pediatric maintenance liver transplant recipients.

Cyclosporine absorption has been key to obtaining adequate results in immunosuppressive regimens. Since 2005, we have used a different monitoring program for Cyclosporine among pediatric liver transplant recipients namely, two hours post dosing concentrations (O(2)). This study of 128 patients included 50.8% males and 64.8% recipients of cadaveric livers. Their main reasons for transplantation were as follows: 43.8% acute liver failure and 37.5% biliary atresia. Mean age at time of transplantation was 5.4 +/- 4.5 years for boys and 3.4 +/- 3.3 years for girls. Mean age at the beginning of C(2) monitoring was 8.9 +/- 4.8 years and time elapsed since transplantation was 53.6 +/- 36.4 months. The initial Cyclosporine dose of 5.5 +/- 5 mg/kg/d had been reduced by month 24 to 4.5 +/- 1.5 mg/kg/d. Estimation of glomerular filtration rate (eGFR) was performed using the Schwartz formula. Baseline creatinine and eGFR were 0.73 +/- 0.49 mg/dL and 111.99 +/- 28.27 mL/min.m(2) versus 24-month creatinine and eGFR of 0.69 +/- 0.20 mg/dL and 122.26 +/- 24.47 mL/min.m(2), respectively (P < .05). Eight patients experienced acute rejection episodes, 4 had chronic rejection, 3 posttransplantation proliferative diseases (PTLD) were reported, and 2 patients died. Cyclosporine C2 monitoring allowed a trend toward long-term dose reduction. Consequently we observed significant improvement in renal function. Acute/chronic rejection rates were low, which suggested that C(2) monitoring was effective to control immunosuppressive therapy.The low incidence of PTLD and patient mortality showed that there was an adequate balance between safety and efficacy profiles.