D.G. Kim

Benefit of downsizing hepatocellular carcinoma in a liver transplant population

Aliment Pharmacol Theru200231, 415–423

High Mortality Associated With Acinetobacter Species Infection in Liver Transplant Patients

BACKGROUNDnAcinetobacter species have become increasingly important nosocomial pathogens worldwide and can result in a wide range of infections, including bacteremia, pneumonia, urinary tract infection, peritonitis, among others. The aim of this study was to investigate clinical characteristics, mortality, and outcomes among liver transplant recipients with Acinetobacter species infections.nnnMETHODSnWe retrospectively analyzed 451 subjects who had undergone living donor liver transplantations between January 2001 and May 2010. Pandrug-resistant (PDR) Acinetobacter species were defined as resistant to all commercially available antibiotics except colistin.nnnRESULTSnInfectious complications due to Acinetobacter species appeared in 26 patients (5.8%) with a total of 37 episodes. Of the species identified, 34 were Acinetobacter baumannii and 3 Acinetobacter Iwoffiii. The presumed sources of infection were the biliary tract (n = 21, 56.8%), lung (n = 7, 18.9%), intra-abdomen (n = 6, 16.2%), catheter (n = 2, 5.4%), and urinary tract (n = 1, 3.6%). Among the 37 Acinetobacter species, 75.7% (28/37) were PDR species. Age, duration of intensive care unit stay, Child-Pugh score, and Model for End-stage Liver Disease score were not significant risk factors for Acinetobacter species infection. However, the overall mortality among patients with Acinetobacter species infections was 50% (13/26), which was significantly higher than that among those free of infection (50% vs 11.5%, P < .05). Multivariate analysis using a Cox regression model showed that inappropriate antimicrobial treatment was a significant independent risk factor for mortality among patients with Acinetobacter species infections (hazard Ratio = 4.19, 95% confidence interval 1.1-18.7; P = .06).nnnCONCLUSIONnPatients with Acinetobacter species infections after liver transplantation show a significantly worse prognosis. PDR Acinetobacter species have been a major problem in our center.

Single-Port Laparoscopy-Assisted Donor Right Hepatectomy in Living Donor Liver Transplantation: Sensible Approach or Unnecessary Hindrance?

BACKGROUNDnSingle-port laparoscopic (SPL) surgery has rapidly gained attention worldwide. Since May 2008, we have propagated the use of SPL surgery, mainly for cholecystectomy and appendectomy. Recently, we have used this modality of minimally invasive surgery for various liver surgeries. We hereby discuss our outcomes of SPL-assisted donor right hepatectomies.nnnMETHODSnThe preoperative workup is the same as for a standard donor hepatectomy. We retrospectively reviewed the data of 150 patients who underwent donor right hepatectomy from October 2008 to May 2011. We divided them into 3 groups depending on the type of surgical procedure.nnnRESULTSnAmong 150 patients, 20 underwent laparoscopy-assisted donor right hepatectomy (LADRH); 40 underwent single-port laparoscopy-assisted donor right hepatectomy (SPLADRH); and 90 underwent open donor right hepatectomy (ODRH). The donor demographics were comparable among the groups. Postoperative complication and reoperation rates revealed no significant differences. The SPLADRH group showed the lowest level of postoperative pain, thereby leading to a better quality of life postoperatively.nnnCONCLUSIONSnSPLADRH seems to be a simple, feasible approach.

Surgical Techniques According to Anatomic Variations in Living Donor Liver Transplantation Using the Right Lobe

OBJECTIVESnIn living donor liver transplantation, the right lobe has many anatomic variations in the vascular tree, which could lead to surgical complications. We need to define surgical technique according to anatomy.nnnMETHODSnFrom January 2000 to September 2007, 310 living donor liver transplantations using the right lobe were performed in patients with end-stage liver disease. The vascular trees were evaluated preoperatively with computed tomography and magnetic resonance angiography. We classified anatomic points for safe harvest in the hepatic artery, portal vein, and hepatic vein and described technical points based on anatomic variations.nnnRESULTnThere were many anatomic variations in the hepatic vasculature. Hepatic artery variations were observed in 16.8% of cases. Double hepatic artery was observed in 14 cases (4.5%). Of these 14 cases, reconstruction as a single artery was performed in 6 and dual reconstruction was performed in 8 cases. Portal vein variation was observed in 45 cases (14.5%): Dual anastomosis to right and left portal vein was performed in type III (n = 20; 6.4%) and type IV (n = 3; 1.0%) variations. There were 70 cases of portal vein thrombosis. In 8 of the 70, a jump or interposition graft with iliac vein was utilized. Of the middle hepatic vein variant, segment V vein only was reconstructed in 188 (60.6%) cases. In 21 (6.8%) cases, segment VIII vein only was reconstructed, and in 43 (13.9%) cases, both segment V and segment VIII veins were reconstructed using the recipients portal vein, a cryopreserved iliac vein, or a prosthetic graft. The most common variation of right inferior hepatic vein was type II (n = 141; 45.5%), which has 1 right inferior hepatic vein.nnnCONCLUSIONnLiving donor liver transplantation using the right lobe can be performed safely, but there is a potential operative risk because of various anatomic variations. To minimize operative complications, anatomic variations should be kept in mind to ensure a safe and successful operation.

Correlation of Portal Venous Velocity and Portal Venous Flow With Short-Term Graft Regeneration in Recipients of Living Donor Liver Transplants

BACKGROUNDnTo evaluate the correlation of postoperative portal venous velocity (PVV) and portal venous flow (PVF) with the degree of short-term graft regeneration in recipients of living donor liver transplantation (LDLT).nnnMATERIALS AND METHODSnBetween August 2005 and April 2006, we performed 44 adult-to-adult LDLTs with right-lobe grafts, of whom 31 recipients were included in this study. Doppler ultrasonography was used to measure PVV (cm/s) and PVF (mL/min) on postoperative days (POD) 1, 3, and 5 or 6. Portal venous velocity index (PVI) was defined as the ratio of PVV to graft weight (GW), and portal flow volume index (PFI) as the ratio of PVF to GW. Graft regeneration rate (GRR), defined as the ratio of the volume of regenerated graft to GW, was estimated by dividing computed tomography volumetry at POD 7 by GW measured after retrieval of the graft. We analyzed the relationship between GRR and PVV, PVF, PVI, and PFI.nnnRESULTSnGW ranged between 528 g and 1040 g (mean = 735 g) and GRR ranged between 118% and 278% (mean = 172%). Although neither PVV nor PVF correlated with GRR, PVI and PFI at POD 1 (P = .009) and PFI at POD 5 or 6 (P = .012) significantly correlated with GRR at POD 7.nnnCONCLUSIONnPVI and PFI at POD 1 are useful indicators to predict short-term graft regeneration in recipients of LDLT.

Performance of Posttransplant Model for End-Stage Liver Disease (MELD) and Delta-MELD Scores on Short-Term Outcome After Living Donor Liver Transplantation

The performance of the Model for End-stage Liver Disease (MELD) and delta-MELD scores in predicting posttransplant survival has been variable and the results are conflicting, suggesting that posttransplantational factors are more important than pre- or peritransplantational factors in outcomes following liver transplantation (OLT). We assessed the value of posttransplant MELD and delta-MELD scores to predict short-term (90-day) posttransplant survival. We evaluated 279 consecutive patients undergoing living donor OLTs. The MELD scores were calculated serially from pretransplantation as well as 3, 7, and 14 days after transplantation. Twenty-seven (9.7%) among 279 patients died within 90 days after transplantation. Pretransplant MELD score was not associated with short-term posttransplant mortality. The area under the receiver operating characteristic (AUROC) curve in predicting 90-day mortality was 0.637 for posttransplant 3-day MELD, 0.746 for posttransplant 7-day MELD, and 0.859 for posttransplant 14-day MELD score (P = .047, <.001, and <.001, respectively); AUROC was 0.582, 0.646, and 0.784 for 3-day, 7-day, and 14-day delta-MELD scores (P = .235, .034, <.001, respectively). Upon multivariate analysis, posttransplant 14-day MELD (> or =20 vs <20), and 14-day delta-MELD scores (> or =-3 vs <-3) were independent short-term prognostic factors with risk ratios of 18.875 (95% confidential interval [CI]: 4.625-77.028, P < .001) and 13.577 (95% CI: 2.641-69.791, P = .002), respectively. In conclusion, determination of posttransplant 14-day MELD and 14-day delta-MELD scores may afford suitable short-term prognostic predictors for patients following living donor OLT.

Extended Criteria for Living Donor Liver Transplantation in Patients With Advanced Hepatocellular Carcinoma

BACKGROUNDnThe purpose of this study was to evaluate the possibility of expanding the selection criteria in living donor liver transplantation (LDLT) to treat hepatocellular carcinoma (HCC).nnnMETHODSnFrom October 2000 to December 2010, we retrospectively analyzed 71 patients who had undergone LDLT beyond the Milan criteria (MC), among the entire cohort of 199 HCC patients. We evaluated the tumor biology as well as overall and disease-free survival (DFS), seeking to identify risk factors for recurrence. The median follow-up was 37 months (range 5-124).nnnRESULTSnAmong the 71 patients beyond the MC were 18 recurrences and 30 deaths. Their 5-year overall and DFS rates were 52.3% and 67.7%, respectively. On multivariate analysis, tumor diameter, tumor number, and E-S grade significantly influenced overall and DFS. According to our new criteria (size≤7 cm, number≤7), 86% of our patients would be included compared with 64% using MC. Five-year DFS and overall survival rates according to our criteria were comparable with the MC: 86.8% and 72.3% versus 86.8% and 73.4%, respectively.nnnCONCLUSIONnOur criteria appear to achieve useful cut-off values beyond the MC.

Intraoperative Changes in Hyponatremia as a Risk Factor for Prolonged Mechanical Ventilation After Living Donor Liver Transplantation

Prolonged mechanical ventilation (PMV), a common clinical manifestation, may result in fatal outcomes after living donor liver transplantation (LDLT). Although hyponatremia contributes to neurologic alterations in association with PMV, the effects of acute changes in hyponatremia during LDLT have not been well studied. We sought to determine whether an acute change in hyponatremia during surgery might be a risk factor for PMV after LDLT. Perioperative data were retrospectively collected from 381 patients who underwent LDLT from January 2000 to December 2008. PMV was defined as the need for ≥24 hours of mechanical ventilation within the first postoperative week. Using multivariate logistic regression a simple comparison of perioperative variables between the PMV group and the non-PMV group yielded a predictive model to establish PMV. Thirty-seven patients (9.7%) experienced PMV after LDLT. Intraoperative changes in blood sodium were associated with postoperative PMV; however, the relationship was limited to patients with preoperative hyponatremia. Patients with PMV showed lower survival rates than those without PMV (56.3% vs 86.3%; P <.001). A multivariate analysis revealed that preoperative hepatic encephalopathy, hypotension during surgery (more than 3 bowls), and intraoperative changes in hyponatremia were predictive of PMV. Among the hyponatremia change subgroups, only a severe intraoperative change (≥10 mEq/L) was associated with PMV occurrence (odds ratio, 5.85; 95% confidence interval, 1.62 to 21.20, P = .007). In conclusion, a severe intraoperative change in hyponatremia was a risk factor for PMV in the immediate period after LDLT.

Strategies to Reduce Infectious Complication Using Epidemiologic Data Analysis in Liver Transplant Recipients

BACKGROUNDnInfectious complications are major factors for morbidity and mortality in liver transplant recipients. To establish a proper strategy to reduce infectious complications, we analyzed epidemiologic and risk factors for post-transplant infections.nnnMETHODSnWe analyzed the medical records of 231 consecutive liver transplant recipients from December 2007 to November 2011, including at least 1-year follow up, for comparison with those from 1996 toxa02005.nnnRESULTSnAmong 231 patients, 126 (54.5%) experienced 244 infectious episodes, a rate of 1.05 per patient. Among overall mortality of 9.9% (23/231), infections were more prevalent (Pxa0= .04). Predominant infections were postoperative intra-abdominal problems (36.1%), peritonitis (15.2%), pneumonia (13.5%), bacteremia (4.1%), wound complications (1.6%), viral etiologies (18.0%), and other causes (11.5%). Causative organisms were bacterial (68.9%), viral (14.7%), fungal (7.0%), and unproven ones (9.4%). Multivariate analysis of risks for infection showed significant impacts of Model for End-stage Liver Disease score [Pxa0= .027; odds ratio (OR), 1.04], post-transplant biliary complications (Pxa0< .001; OR, 3.50), and rejection episodes (Pxa0= .023; OR, 3.39). Mortality was related to retransplantation (Pxa0= .003), post-transplant dialysis (Pxa0= .006), and infection (Pxa0= .056) upon univariate analysis, none of which were significant in multivariate analysis. Compared with data from the previous period, overall and infection-related mortality decreased from 24.5% to 9.9% and 52.9% to 26.1%, respectively. There were no significant changes in the types of infection or rate of drug-resistant bacteria, but candidal infections and cytomegalovirus reactivations were more prevalent.nnnCONCLUSIONnOur data showed current perioperative antimicrobial regimens need not be changed: however, new strategies are needed to reduce infectious complications after liver transplantation, to reduce biliary complications and to properly manage rejection episodes.

Antiviral Prophylaxis Versus Preemptive Therapy to Prevent Cytomegalovirus Infection and Related Death in Liver Transplantation: A Retrospective Study With Propensity Score Matching

BACKGROUNDnCytomegalovirus (CMV), the most significant viral infection in liver transplant recipients, is addressed by 2 methods: Preemptive therapy (PT) or universal prophylaxis (UP).nnnMETHODSnWe analyzed medical records including at least 1 year follow-up of patients who underwent liver transplantation from 2006 to 2009 in 3 tertiary hospitals. PT was used in 2 hospitals (PT group), whereas UP with valganciclovir for 3 months was adopted in the other hospital (UP group). The 2 groups were matched using propensity scoring by perioperative variables. We performed a 1:1 comparison of the efficacy of UP and PT.nnnRESULTSnWe analyzed 634 liver transplant patients, including 562 matched subjects. Baseline characteristics and underlying liver status were comparable. CMV immunoglobulin G of recipients was positive in 98.9% of the PT group and 99.3% of the UP group. CMV viremia episodes that required administration of an antiviral agent occurred in 26 (9.3%) PT and 37 (13.2%) UP subjects (P = .18). CMV-related mortalities were similar (0.7% vs 1.8%; P = .45), but all-cause mortality was higher in the PT group (18.5% vs 13.2%; P = .08).nnnCONCLUSIONnThe efficacy of PT was similar to UP to prevent CMV disease and related mortality among a group at moderate risk for CMV infection.