Pharmacokinetics of Voriconazole in Peritoneal Fluid of Critically Ill Patients.

Data on the distribution of voriconazole (VRC) in the human peritoneal cavity are sparse. This prospective study aimed to describe the pharmacokinetics of intravenous VRC in the peritoneal fluid of critically ill patients. A total of 19 patients were included. Individual pharmacokinetic curves, drawn after single (first dose on day 1) and multiple (steady-state) doses, displayed a slower rise and lower fluctuation of VRC concentrations in peritoneal fluid than in plasma. Good but variable penetration of VRC into the peritoneal cavity was observed, and the median (range) peritoneal fluid/plasma ratios of the area under the concentration-time curve (AUC) were 0.54 (0.34 to 0.73) and 0.67 (0.63 to 0.94) for single and multiple doses, respectively. Approximately 81% (13/16) of the VRC steady-state trough concentrations (Cmin,ss) in plasma were within the therapeutic range (1 to 5.5 µg/mL), and the corresponding Cmin,ss (median [range]) in peritoneal fluid was 2.12 (1.39 to 3.72) µg/mL. Based on the recent 3-year (2019 to 2021) surveillance of the antifungal susceptibilities for Candida species isolated from peritoneal fluid in our center, the aforementioned 13 Cmin,ss in peritoneal fluid exceeded the MIC90 of C. albicans, C. glabrata, and C. parapsilosis (0.06, 1.00, and 0.25 µg/mL, respectively), which supported VRC as a reasonable choice for initial empirical therapies against intraabdominal candidiasis caused by these three Candida species, prior to the receipt of susceptibility testing results.

Population pharmacokinetics and limited sampling strategies of polymyxin B in critically ill patients.

OBJECTIVES: To characterize the pharmacokinetics (PK) of polymyxin B in Chinese critically ill patients. The factors significantly affecting PK parameters are identified, and a limited sampling strategy for therapeutic drug monitoring of polymyxin B is explored. METHODS: Thirty patients (212 samples) were included in a population PK analysis. A limited sampling strategy was developed using Bayesian estimation, multiple linear regression and modified integral equations. Non-linear mixed-effects models were developed using Phoenix NLME software. RESULTS: A two-compartment population PK model was used to describe polymyxin B PK. Population estimates of the volumes of central compartment distribution (V) and peripheral compartment distribution (V2), central compartment clearance (CL) and intercompartmental clearance (Q) were 7.857 L, 12.668 L, 1.672 L/h and 7.009 L/h. Continuous renal replacement therapy (CRRT) significantly affected CL, and body weight significantly affected CL and Q. The AUC0-12h of polymyxin B in patients with CRRT was significantly lower than in patients without CRRT. CL and Q increased with increasing body weight. A limited sampling strategy was suggested using a two-sample scheme with plasma at 0.5h and 8h after the end of infusion (C0.5 and C8) for therapeutic drug monitoring in the clinic. CONCLUSIONS: A dosing regimen should be based on body weight and the application of CRRT. A two-sample strategy for therapeutic drug monitoring could facilitate individualized treatment with polymyxin B in critically ill patients.

Voriconazole pharmacokinetics in a critically ill patient during extracorporeal membrane oxygenation.

The pharmacokinetics (PK) of several drugs including antimicrobials might be highly altered during extracorporeal membrane oxygenation (ECMO) therapy. We present the change of voriconazole (VRC) PK during ECMO in a critically ill patient who received intravenous VRC at a maintenance dose of 200 mg every 12 h for empirical antifungal therapy. Two PK profiles were drawn before and after the initiation of ECMO therapy. Though the trough levels (both C0 and C12) with ECMO were slightly lower than that without ECMO (12.58 and 12.84 vs. 14.02 µg/mL), the peak levels and the area under the concentration-time curve from 0 h to 6 h (AUC0-6) were comparable (16.36 vs. 16.06 µg/mL and 90.78 vs. 91.45 µg·h/mL, respectively), indicating that VRC plasma exposure during ECMO therapy did not greatly decrease in our patient. The circuit factors including the type of membrane should be taken into account to further identify the effects of ECMO on the PK of VRC.

Population pharmacokinetic model-guided optimization of intravenous voriconazole dosing regimens in critically ill patients with liver dysfunction.

STUDY OBJECTIVES: This study aimed to establish a population pharmacokinetic (PPK) model of intravenous voriconazole (VRC) in critically ill patients with liver dysfunction and to explore the optimal dosing strategies in specific clinical scenarios for invasive fungal infections (IFIs) caused by common Aspergillus and Candida species. DESIGN: Prospective pharmacokinetics study. SETTING: The intensive care unit in a tertiary-care medical center. PATIENTS: A total of 297 plasma VRC concentrations from 26 critically ill patients with liver dysfunction were included in the PPK analysis. METHODS: Model-based simulations with therapeutic range of 2-6 mg/L as the plasma trough concentration (Cmin ) target and the free area under the concentration-time curve from 0 to 24 h (ƒAUC24 ) divided by the minimum inhibitory concentration (MIC) (ie, ƒAUC24 /MIC) ≥25 as the effective target were performed to optimize VRC dosing regimens for Child-Pugh class A and B (CP-A/B) and Child-Pugh class C (CP-C) patients. RESULTS: A two-compartment model with first-order elimination adequately described the data. Significant covariates in the final model were body weight on both central and peripheral distribution volume and Child-Pugh class on clearance. Intravenous VRC loading dose of 5 mg/kg every 12 h (q12h) for the first day was adequate for CP-A/B and CP-C patients to attain the Cmin target at 24 h. The maintenance dose regimens of 100 mg q12h or 200 mg q24h for CP-A/B patients and 50 mg q12h or 100 mg q24h for CP-C patients could obtain the probability of effective target attainment of >90% at an MIC ≤0.5 mg/L and achieve the cumulative fraction of response of >90% against C. albicans, C. parapsilosis, C. glabrata, C. krusei, A. fumigatus, and A. flavus. Additionally, the daily VRC doses could be increased by 50 mg for CP-A/B and CP-C patients at an MIC of 1 mg/L, with plasma Cmin monitored closely to avoid serious adverse events. It is recommended that an appropriate alternative antifungal agent or a combination therapy could be adopted when an MIC ≥2 mg/L is reported, or when the infection is caused by C. tropicalis but the MIC value is not available. CONCLUSIONS: For critically ill patients with liver dysfunction, the loading dose of intravenous VRC should be reduced to 5 mg/kg q12h. Additionally, based on the types of fungal pathogens and their susceptibility to VRC, the adjusted maintenance dose regimens with lower doses or longer dosing intervals should be considered for CP-A/B and CP-C patients.

Pharmacokinetics of intravenous voriconazole in patients with liver dysfunction: A prospective study in the intensive care unit.

OBJECTIVES: To characterize the pharmacokinetics (PK) of intravenous voriconazole (VRC) in critically ill patients with liver dysfunction. METHODS: Patients with liver dysfunction in the intensive care unit (ICU) were included prospectively. The Child-Pugh score was used to categorize the degree of liver dysfunction. The initial intravenous VRC dosing regimen comprised a loading dose of 300 mg every 12 h for the first 24 h, followed by 200 mg every 12 h. The first PK curves (PK curve 1) were drawn within one dosing interval of the first dose for 17 patients; the second PK curves (PK curve 2) were drawn within one dosing interval after a minimum of seven doses for 12 patients. PK parameters were estimated by non-compartmental analysis. RESULTS: There were good correlations between the area under the curve (AUC0-12) of PK curve 2 and the corresponding trough concentration (C0) and peak concentration (Cmax) (r2 = 0.951 and 0.963, respectively; both p < 0.001). The median half-life (t1/2) and clearance (CL) of patients in Child-Pugh class A (n = 3), B (n = 5), and C (n = 4) of PK curve 2 were 24.4 h and 3.31 l/h, 29.1 h and 2.54 l/h, and 60.7 h and 2.04 l/h, respectively. In the different Child-Pugh classes, the CL (median) of PK curve 2 were all lower than those of PK curve 1. The apparent steady-state volume of distribution (Vss) of PK curve 1 was positively correlated with actual body weight (r2 = 0.450, p = 0.004). The median first C0 of 17 patients determined on day 5 was 5.27 (2.61) µg/ml, and 29.4% of C0 exceeded the upper limit of the therapeutic window (2-6 µg/ml). CONCLUSIONS: The CL of VRC decreased with increasing severity of liver dysfunction according to the Child-Pugh classification, along with an increased t1/2, which resulted in high plasma exposure of VRC. Adjusted dosing regimens of intravenous VRC should be established based on Child-Pugh classes for these ICU patients, and plasma concentrations should be monitored closely to avoid serious adverse events.

Pseudogene integrator complex subunit 6 pseudogene 1 (INTS6P1) as a novel plasma-based biomarker for hepatocellular carcinoma screening.

In this study, we aimed to determine whether the pseudogene integrator complex subunit 6 pseudogene 1 (INTS6P1) in plasma could be used as a novel approach to screen for and detect hepatocellular carcinoma (HCC). We explored the clinical role of INTS6P1: First, the expression level of INTS6P1 was measured in a cohort of 33 HCC tissue samples and adjacent normal liver tissue, next, the INTS6P1 expression was detected in the culture medium and tumor cells in a cellular experiment, and last, the diagnostic performance of INTS6P1 was examined in an independent cohort of 100 people. The expression level of INTS6P1 was remarkably downregulated in the HCC tissues compared with that in the normal liver tissues (p = 0.0066). In plasma, the INTS6P1 levels were significantly decreased in HCC patients compared with non-HCC patients (p < 0.01). Additionally, we inferred that INTS6P1 might be a prospective biomarker for screening HCC patients in which the serum-AFP levels were lower than 20 ng/ml by the area under the curve-receiver operating characteristic (AUC-ROC) analysis (p < 0.05). Pseudogene INTS6P1 could be used as a novel HCC plasma-based biomarker and might improve the accuracy of HCC screening.

Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs.

Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P<0.05). And there was no significant difference between DBD group and DBCD group (P>0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.

A technique of recipient portal venoplasty and cuff insertion for portal revascularization in orthotopic rat liver transplantation.

BACKGROUND: In addition to suprahepatic vena cava anastomosis in two-cuff rat liver transplantation, recipient portal vein revascularization is one of the most difficult procedures that must be performed, especially for beginners. MATERIALS AND METHODS: A total of 43 cases of liver transplantation were performed. Rats in Group 1 and Group 2 were subjected to transplant procedures that used the conventional and portal venoplasty techniques, respectively. The portal vein anastomosis duration, anhepatic phase length, portal vein surgical complications, and 1 wk post-transplant survival rates were recorded for each group. RESULTS: The portal revascularization duration was statistically significantly less for Group 2 versus Group 1 (1.50 ± 0.61 min and 4.32 ± 0.67 min, respectively, P < 0.05). The anhepatic phase length of Groups 1 and 2 were 21.79 ± 1.27 min and 18.55 ± 1.47 min, respectively (P < 0.05). No significant differences between the groups were observed in relation to either portal vein surgery complications or 1-week survival rates. CONCLUSIONS: The recipient portal venoplasty and cuff insertion technique is a safe and fast alternative surgical option for portal revascularization in two-cuff rat liver transplantations performed by a single trainee.

Clinical study on prevention of HBV re-infection by entecavir after liver transplantation.

PURPOSE: This aims to evaluate the effects of lamivudine (LAM) and entecavir (ETV) in preventing hepatitis B virus (HBV) re-infection after liver transplantation (LT). METHODS: A retrospective matched case-control method was used in this study. From June 2005 to May 2007, the patients who received LAM (100 mg qd) or ETV (0.5 mg qd) were chosen. The LAM and ETV groups were matched using a 3:1 ratio based on the factors, such as age, gender, LAM or ETV antiviral duration, primary disease, and HBV DNA levels at the initiation of antiviral therapy. Data on serum HBV markers, HBV DNA, and cumulative recurrence were collected. RESULTS: Two hundred and fifty-two patients were enrolled. The average duration of follow-up was 38.5 and 41.2 months (LAM and ETV groups) (p>0.05). Duration of pre-operative antiviral therapy was 30.3 and 25.8 d (LAM and ETV groups) (p>0.05). The HBV DNA level decreased from 3.89×10(6) to 5.31×10(5) copies/mL before LT in the LAM group, and decreased from 8.74×10(6) to 5.49×10(4) copies/mL in the ETV group (p<0.05). Eighteen patients in LAM group developed HBV re-infection and 0 in ETV group. CONCLUSION: ETV is superior to LAM for preventing HBV re-infection following LT.

[Preoperative neutrophil-lymphocyte ratio as a prognostic predictor after liver transplantation for hepatocellular carcinoma].

OBJECTIVE: To analyze the negative impact of preoperative neutrophil-lymphocyte ratio (NLR) on the tumor recurrence of hepatocellular carcinoma (HCC) after orthotopic liver transplantation. METHODS: The clinical data of HBV (hepatitis B virus)-associated HCC patients undergoing liver transplantation were retrospectively analyzed. Their clinical and pathological risk factors for tumor-free survival were evaluated by univariate analysis. The analysis of Cox multiple regression was performed to determine the parameters of predicting the HCC recurrence. NLR ≥ 2.5 was considered to be elevated. RESULTS: A total of 76 patients were identified. Among them, 37 had an elevated NLR. The 1, 3 and 5-year tumor-free survival rates were 69.2%, 52.7% and 50.9% respectively. The disease-free survival for patients with high NLR was significantly worse than that for those with normal NLR (1, 3, and 5 year survivals at 56.3%, 37.6% and 37.6% vs 81.1%, 66.9% and 63.3% respectively; P = 0.011). Univariate analysis of factors revealed that tumor size > 5 cm, tumor number > 3, vascular invasion, serum α-fetoprotein level ≥ 400 µg/L and NLR ≥ 2.5 were preoperative predictors of disease-free survival. Cox regression analysis showed that the presence of vascular invasion, tumor number > 3 and NLR ≥ 2.5 were independent prognostic factors of worse disease-free survival. CONCLUSION: An elevated NLR significantly increases the risk for tumor recurrence in HCC patients undergoing liver transplantation.

[The relationship between hepatocellular carcinoma recurrence and hepatitis B virus recurrence after liver transplantation].

OBJECTIVE: To investigate the relationship between hepatocellular carcinoma (HCC) recurrence and hepatitis B virus (HBV) recurrence. METHODS: The clinical data of 340 patients underwent liver transplantation due to HBV related end-stage liver disease and received long-term follow up in our hospital from Jan 2004 to Dec 2008 were retrospectively analyzed. All patients received nucleoside analogues therapy formally before entering into the waiting list and nucleoside analogues combined low-dose HBIG therapy during and after transplantation. Patients were regularly followed up at the outpatient, monitoring the HBV recurrence and survival. Multivariate Cox regression analysis was used to evaluate the risk factors for hepatitis recurrence. RESULTS: 33 patients suffered from HBV recurrence post transplantation. The 1-, 3- and 5- year recurrence rates were 7.0%, 10% and 13% respectively. The median HBV recurrence time was 5 months (1-21 months). COX regression analysis revealed that risk factors for HBV recurrence were HCC (HR = 2.98; 95% CI 1.08-8.25; P < 0.05) and pre-transplantation HBV-DNA load over 5 log10 copies/ml (HR = 3.99; 95% CI 1.85-8.62; P < 0.01). Further stratified analysis showed that patients who suffered from carcinoma recurrence had a higher incidence of HBV recurrence than those who did not, which were 27.9% and 8.7% (HR = 4.58;95% CI 1.88-11.12; P < 0.01) respectively. 12 patients suffered from both HCC and HBV recurrence. Spearman correlation analysis demonstrated a strong correlation between HBV and HCC recurrence times (r = 0.583, P < 0.05). CONCLUSIONS: Post transplantation HCC recurrence is a risk factor for HBV recurrence.

High hepatitis B virus DNA level in serum before liver transplantation increases the risk of hepatocellular carcinoma recurrence.

AIM: To analyze the relationship between hepatitis B virus (HBV) and hepatocellular carcinoma (HCC) recurrence in orthotopic liver transplantation (OLT) patients. METHODS: 340 HBV patients with OLT were included in the study; among them were 148 patients with HBV-associated HCC. RESULTS: HCC recurrence rates at 1, 3 and 5 years were 21, 29, and 46%, respectively. Exceeding Milan criteria (hazard ratio, HR = 12.35; 95% confidence interval, CI, 2.80-54.49; p = 0.001), HBV DNA level >5 log(10) copies/ml before transplant (HR = 2.45; 95% CI 1.10-5.45; p = 0.03) and HBV recurrence (HR = 2.27; 95% CI 1.10-4.75; p = 0.03) were significant independent predictors of HCC recurrence. HBV DNA >5 log(10) copies/ml before transplant (HR = 8.65; 95% CI 3.40-21.98; p < 0.001) and concomitance with HCC (HR = 2.79; 95% CI 1.33-5.87; p = 0.007) were predictors of HBV recurrence. Further stratified analysis showed that HBV recurrence was more prevalent in the HCC recurrence group (HR = 4.58; 95% CI 1.88-11.12; p = 0.001). CONCLUSIONS: There is a close relationship between HBV and HCC recurrence after transplant. High HBV DNA levels before transplant are associated with HCC recurrence after transplant.

Prognostic factors for late mortality after liver transplantation for benign end-stage liver disease.

BACKGROUND: There are increasing numbers of patients who survive more than one year after liver transplantation. Many studies have focused on the early mortality of these patients. However, the factors affecting long-term survival are not fully understood. This study aims to evaluate prognostic factors predicting long-term survival and to explore measures for improving the survival outcomes of patients who underwent liver transplantation for benign end-stage liver diseases. METHODS: The causes of late death after liver transplantation and potential prognostic factors were retrospectively analyzed for 221 consecutive patients who underwent liver transplantation from October 2003 to June 2008. Twenty-seven variables were assessed using the Kaplan-Meier method, and those variables found to be univariately significant at P < 0.10 were entered into a backward step-down Cox proportional hazard regression analysis to identify the independent prognostic factors influencing the recipients' long-term survival. RESULTS: Twenty-eight recipients died one year after liver transplantation. The major causes of late mortality were infectious complications, biliary complications, and Hepatitis B virus recurrence/reinfection. After Cox analysis, the five remaining co-variables were: age, ABO blood group, cold ischemia time, post-infection region, and biliary complications. CONCLUSIONS: The major causes of late mortality were infection, biliary complications and Hepatitis B virus recurrence/reinfection. Five variables (Age, ABO blood group, cold ischemia time, infection, and biliary complications) had significant impacts on patient survival.

[Clinical analysis between "early" versus "late" liver retransplantation].

OBJECTIVE: To compare early and late orthotopic liver retransplantation (re-OLT) for patients with poor graft function after primary transplantation at our center and sum up our clinical experience in re-OLT. METHODS: The clinical data of 36 re-OLTs from January 2004 to July 2009 were analyzed retrospectively, consisting of the first group with 17 cases of early re-OLT and the second group with 19 cases of late re-OLT. The average ages were (45 ± 13) years and (48 ± 10) years, and the time intervals were (49 ± 54) days and (514 ± 342) days in early re-OLT group and late re-OLT group, respectively. RESULTS: Biliary tract complications were the main indications for early re-OLT and late re-OLT. Other common indications were vascular complications in early re-OLT and recurrence of primary diseases in late re-OLT. No significant differences were found between the groups with regard to the volume of bleeding during operation, cold ischemia time, operative duration and perioperative mortality except the MELD score. Outcome was fatal for 8 patients in early re-OLT and 10 patients in late re-OLT. Three deaths were due to severe sepsis-related disease, 3 deaths due to multiple organ failure in early re-OLT and 4 deaths due to severe sepsis-related disease, 3 deaths due to recurrence of HCC in late re-OLT. One and 2-year actuarial survival rates after re-OLT were 52.9% and 41.2%, respectively, for patients in early re-OLT, and 63.2% and 52.6%, respectively, for patients in late re-OLT. No significant differences were found regarding survival rates between the two groups (P > 0.05). CONCLUSIONS: The similar clinical results can be achieved in early and late re-OLT. Proper indications and optimal operation timing, experienced surgical procedures and effective perioperative anti-infection strategy contribute to the improvement of the overall survival rate of the patients after re-OLT.

[Risk factors predicting late mortality after liver transplantation for benign end-stage liver disease].

OBJECTIVES: To find out the risk factors predicting long-term survival, and to explore the measures for further improving the survival outcome of whom underwent liver transplantation (LT) for benign end-stage liver disease. METHODS: The common causes of late death after LT and risk factors were retrospectively analyzed in 221 consecutive patients, who underwent LT from October 2003 to June 2007 and survived more than one year. Twenty-six potential risk factors were assessed by the Kaplan-Meier method, and those variables found to be univariately significant at P < 0.10 were entered into a backward step down Cox proportional hazard regression analysis to screen the independent risk factors influencing the recipient's long-term survival. RESULTS: There were 28 recipients died one year later after LT during the follow-up period. The major causes of late mortality were related to infectious complications 5.0% (11/221), biliary complications 3.6% (8/221) and HBV recurrence/reinfection 1.4% (3/221). After Cox proportional hazard regression analysis, 5 covariables finally retained in the formula were: age (RR = 2.325, P = 0.009), ABO blood group (RR = 2.206, P = 0.015), cold ischemia time (RR = 3.001, P = 0.000), post-infection region (RR = 1.665, P = 0.007) and biliary complications (RR = 2.655, P = 0.004). CONCLUSION: Age (≥ 60 years), ABO blood group (incompatible), cold ischemia time (> 12 h), infectious complications (lung infection) and biliary complications (diffuse biliary stricture) significantly impact patient's survival time.

Liver transplantation for end-stage alcoholic liver disease: a single-center experience from mainland China.

There has been a gradual increase in the number of patients with end-stage alcoholic liver disease (ALD) undergoing liver transplantation (LT) in mainland China. However, few studies have focused on the post-transplant outcomes of this population. The aim of this study was to evaluate the efficacy of LT in patients with ALD, mainly focusing on survival rates, complications, and alcohol recidivism. The results were retrospectively analyzed from 20 patients, who underwent LT for ALD from December 2003 to September 2007 at Liver Transplant Center of Third Affiliated Hospital of Sun Yat-sen University. The 1-, 2-, and 3-year survival rates of the ALD group and non-ALD group were 90.0, 80.0, 80.0% and 90.3, 84.7, 79.8%, respectively. There was no significant difference in 1-, 2-, and 3-year survival rates between these two groups (P=.909). No significant difference was observed in complications such as pulmonary infection (50.0 vs. 31.9%, P=.137), biliary complications (15.0 vs. 27.4%, P=.297), hepatic arterial complications (10.0 vs. 6.9%, P=.641), and rejection (15.0 vs. 8.1%, P=.394) after LT between the ALD group and non-ALD group. There was only one person who resumed mild, intermittent drinking after LT. End-stage ALD is a good indication for LT, with similar results in non-ALD patients. The major cause of death in ALD patients after LT was infectious complications. More attention is needed for the prophylaxis of infectious complications after LT.

Contrast-enhanced ultrasound for the evaluation of hepatic artery stenosis after liver transplantation: potential role in changing the clinical algorithm.

Hepatic artery stenosis (HAS) is a common complication in liver transplant patients. Conventional angiography remains the gold standard for diagnosis. Recently, contrast-enhanced ultrasound (CEUS) has begun providing real-time angiographic-like images of vessels and allowing the accurate diagnosis of arterial diseases such as hepatic artery thrombosis. The purpose of this study was to evaluate the efficacy of CEUS in depicting HAS after liver transplantation. Forty-seven liver transplant recipients underwent CEUS examinations with the intravenous injection of microbubble contrast agents. The reference standard was conventional angiography for 15 patients and computed tomographic angiography for 32 patients. The presence, degree, location, and type of HAS were evaluated. For the detection of HAS by CEUS, the following was found: an accuracy of 91.5% (43/47), a sensitivity of 92.3% (36/39), a specificity of 87.5% (7/8), a positive predictive value of 97.3% (36/37), and a negative predictive value of 70% (7/10). CEUS corrected false-positive findings on color Doppler ultrasound in 7 of 47 cases (14.9%). The accuracy of CEUS in identifying the location and type of HAS was 92.3% (36/39) and 84.6% (33/39), respectively. CEUS is a useful noninvasive technique for the detection of HAS in liver transplant patients because it provides comprehensive information, including the presence, location, degree, and type. A positive CEUS finding suggests angiography as the next step rather than a computed tomography scan and may thereby alter the clinical imaging algorithm.

[Effect of artificial liver support system on the survival rate of high risk patients after liver transplantation].

OBJECTIVE: To observe the effect of artificial liver support system (ALSS) after liver transplantation on the survival rate of severe hepatitis patients. METHODS: Patients with severe hepatitis with model for end stage liver disease (MELD) score above 35 were divided into two groups according to whether pre-transplantation ALSS was instituted (n=23) or not (n=41). Evaluation was performed on the day when the patient entered into the waiting list and 1 day pre-transplantation. Survival rates and survival curves were estimated with Kaplan-Meier method. Log-Rank test for trends was used when comparing curves. RESULTS: There was no significant difference between two groups when comparing the parameters including prothrombin time, fibrinogen, total bilirubin, blood ammonia, creatinine, MELD score on the day of entering into the waiting list (all P>0.05). After the therapy of ALSS, the parameters of ALSS group were significantly improved comparing to those of the control group (all P<0.01). MELD score of ALSS group on the day pre-transplant was decreased significantly comparing to that on the day entering into the waiting list (37.6+/-2.0 vs. 41.4+/-2.2, P<0.01), with the difference in MELD score (DeltaMELD) of -3.8. MELD score of control group on the day entering into the waiting list and 1 day pre-transplant was 40.6+/-1.7 and 41.0+/-1.6 respectively, with DeltaMELD of +0.4 ( P>0.05). The blood loss and operation time in ALSS group was significantly less than the control group [(4 070.0+/-688.1) ml vs. (4 905.9+/-1 142.1) ml, (9.4+/-1.1) hours vs. (10.5+/-1.0) hours, P<0.05 and P<0.01). Thirty days and 1 year survival rate of ALSS group was 91% and 82%, and that of control group was 76% and 59% respectively (P=0.044). CONCLUSION: ALSS can improve the survival rate of patients with severe hepatitis undergoing liver transplantation through ameliorating physiological status, lessening blood loss during operation and operation time.

Characteristics of ambient volatile organic compounds (VOCs) measured in Shanghai, China.

To better understand the characteristics of ambient abundance of volatile organic compounds (VOCs) in Shanghai, one of the biggest metropolis of China, VOCs were measured with a gas chromatography system equipped with a mass-selective detector (GC/MSD) from July 2006 to February 2010. An intensive measurement campaign was conducted (eight samples per day with a 3 hour interval) during May 2009. The comparison of ambient VOCs collected in different regions of Shanghai shows that the concentrations are slightly higher in the busy commercial area (28.9 ppbv at Xujiaui) than in the urban administrative area (24.3 ppbv at Pudong). However, during the intensive measurement period, the concentrations in the large steel industrial area (28.7 ppbv at Baoshan) were much higher than in the urban administrative area (18 ppbv at Pudong), especially for alkanes, alkenes, and toluene. The seasonal variations of ambient VOC concentrations measured at the Xujiahui sampling site indicate that the VOC concentrations are significantly affected by meteorological conditions (such as wind direction and precipitation). In addition, although alkanes are the most abundant VOCs at the Xujiahui measurement site, the most important VOCs contributing to ozone formation potential (OFP) are aromatics, accounting for 57% of the total OFP. The diurnal variations of VOC concentrations show that VOC concentrations are higher on weekdays than in weekends at the Xujiahui sampling site, suggesting that traffic condition and human activities have important impacts on VOC emissions in Shanghai. The evidence also shows that the major sources of isoprene are mainly resulted from gasoline evaporation at a particular time (06:00-09:00) in the busy commercial area. The results gained from this study provide useful information for better understanding the characteristics of ambient VOCs and the sources of VOCs in Shanghai.