Perioperative intra- and extravascular volume in liver transplant recipients.

UNLABELLED: Assessing adequate volemia to avoid fluid overload and pulmonary edema perioperatively in liver transplantation (LT) is a challenge both for the anesthetist and the intensivist. Volumetric preload indices, such as intrathoracic blood volume index (ITBVI), measured by transpulmonary thermodilution, and continuous end-diastolic volume index (EDVI), measured by pulmonary artery thermodilution, were shown to better reflect preload than central venous pressure (CVP) or pulmonary artery occlusion pressure (PAOP). An ITBVI increase soon after the graft reperfusion influenced pulmonary perfusion without an alteration of extravascular lung water index (EVLWI) and without impaired oxygenation. This study was designed to evaluate relationships between CVP, PAOP, ITBVI, EDVI, and stroke volume index (SVI) within 48 hours after LT. We also investigated the relationship between EVLWI and arterial partial pressure of oxygen and inspired oxygen fraction ratio (PaO(2)/FiO(2)). METHODS: We enrolled 125 patients (103 men and 22 women) undergoing LT. All patients were monitored with the PiCCO system (Pulsion Medical System) and with advanced pulmonary artery catheter connected to the Vigilance System. Hemodynamic-volumetric data were collected upon intensive care unit admission and every 8 hours up to 48 hours. Univariate and multivariate regression models were fitted to assess associations between SVI and EDVI, ITBVI, and filling pressures after adjusting for the right ventricular ejection fraction (RVEF, categorized as ≤30, 31-40, or >40) and the phase of the observation period. We also assessed associations between PaO(2)/FiO(2) and EVLWI. RESULTS: SVI was associated with EDVI, ITBVI, and RVEF. The models showing the best fit to the data were those including EDVI and ITBVI. Neither CVP nor PAOP showed correlation with SVI. EVLWI inversely correlated with PaO(2)/FiO(2). CONCLUSIONS: In the first 48 hours after LT, ITBVI and EDVI were associated with SVI assessment, whereas CVP and PAOP were not related. EVLWI significantly inversely correlated with PaO(2)/FiO(2).

Sequential versus contemporaneous portal and arterial reperfusion during liver transplantation.

Although sequential portal and arterial revascularization (SPAr) is the most common method of graft reperfusion at liver transplantation (OLT), contemporaneous portal and hepatic artery revascularization (CPAr) has been used to reduce arterial ischemia to the bile ducts. The aim of this study was to prospectively compare SPAr (group 1; n=19) versus CPAr (group 2; n=21) among 40 consecutive OLT from heart-beating donors. There were no differences in the demographics characteristics, Model for End-stage Liver Disease scores, indication for OLT and donor parameters between the groups. OLT was performed using the piggyback technique. The biliary anastomosis was performed in all cases by a duct-to-duct technique with a T-tube in 32% versus 29% of cases without a T tube (P=.83). In the CPAr group, the liver was reperfused simultaneously via the portal vein and hepatic artery. CPAr showed a longer warm ischemia (66 ± 8 vs 37 ± 7 minutes; P<.001), while SPAr had a longer arterial ischemia 103 ± 42 vs 66 ± 8 minutes (P=.0004). Recovery of graft function was similar. There was no primary nonfunction and delayed graft function occurred among 10% versus 9%. Liver function tests were similar between the two groups up to 90 days case of follow-up- One-year graft and patient survivals were, respectively, 89% and 95% versus 94% and 100% (P=.29). At a median follow-up of 13 ± 6 versus 14 ± 7 months, biliary complications included anastomotic stenoses in 15% versus 19% (P=.78) and intrahepatic non-anastomotic biliary strictures in 26% versus none (P=.01) for SPAr and CPAr, respectively. CPAr was safe and feasible, reducing the incidence of intrahepatic biliary strictures by decreasing the duration of arterial ischemia to the intrahepatic bile ducts.

Perioperative considerations in HIV-infected liver transplanted patients.

UNLABELLED: The introduction of highly active antiretroviral therapy (HAART) has improved survival in HIV patients, allowing them to undergo liver transplantation (OLT) in cases of end-stage liver disease. HIV patients show a higher incidence of pulmonary hypertension. The aim of this study was to evaluate pulmonary and systemic hemodynamic changes in HIV-infected patients compared with a non-HIV-infected group of patients undergoing OLT. METHODS: We analyzed 20 HIV-infected patients and 20 non-HIV-infected patients who underwent OLT. We analyzed preoperative cardiovascular status, as well as intra- and postoperative hemodynamic data. Hemodynamic data were recorded at 4 predefined phases during OLT and at 24, 48, and 72 hours after intensive care unit (ICU) admission. We also evaluated the following perioperative aspects: transfusion requirements, postoperative mechanical ventilation time, ventilation time, and length of ICU and of hospital stay. RESULTS: HIV-positive patients were younger than controls with a greater incidence of coinfection with hepatotropic viruses. One HIV-infected patient died in the ICU. Hemodynamic data showed a higher cardiac index and higher pulmonary vascular resistance index among HIV-infected patients, but without any clinical impact. No significant difference in blood unit transfusions, postoperative time on mechanical ventilation, or length of ICU or hospital stay was observed between the groups. CONCLUSIONS: Although the number of patients studied is limited, we concluded that HIV-infected patients undergoing OLT showed similar perioperative courses as non-HIV-infected patients.

Involvement of mu class glutathione S-transferase subunit M2 (rGST M2) levels in the initiation and promotion of hepatocellular carcinogenesis in old rats.

Age-associated differences in the response of the initiation and promotion of hepatocellular carcinogenesis in the rat were analyzed. Male Wistar rats 5 and 18 months-old were used throughout. They underwent an experimental design of multistage model of hepatocarcinogenesis: hepatic cells were initiated with the complete carcinogen Aflatoxin B1 (0.5mg/Kg b.w.) and the promotion was performed through a combined treatment of proliferation (partial hepatectomy, 65%) and administration of the tumorigenic promoter phenobarbital (0.1% in drinking water for 21 days). After the treatment, rats were sacrificed and the following parameters were determined: activity and subunit composition of the glutathione S-transferase enzyme system, the number of liver preneoplastic foci and the proliferation cell index. The combined treatment (initiation + promotion) lowered the expression of the mu class GST (rGST M1, rGST M2). The inhibition in rGST M2 in old animals (which in basal conditions had already been lower) was significant. On the other hand, the treatment increased the alpha class GST (rGST A, rGST A3). The number of preneoplastic foci was higher in old rats (number of foci/cm(2): 6.9+/-0.3 vs 3.9+/-0.3 in young rats, p< 0.05). The proliferation cell index did not show age-related differences. Because rGST M2 deficiency coexisted with induced expression of alpha class, the livers would be resistant to some toxic insults, being selectively sensitive to potentially genotoxic substances for which M2 is an essential detoxification pathway. The transition to a rGST M2-deficient phenotype during aging could induce higher responsiveness to genotoxic effects, and might favor the likelihood of further progression, indicating a higher susceptibility of aged animals to the development of carcinogenesis.

Prevention of post-herpetic neuralgia: acyclovir and prednisolone versus epidural local anesthetic and methylprednisolone.

BACKGROUND: Treatment of herpes zoster (HZ) includes the use of acyclovir with or without steroids. An alternative therapy is the epidural administration of local anesthetics with or without steroids. This trial compared the efficacy of these two treatment regimens in the prevention of post-herpetic neuralgia (PHN). METHODS: Six hundred adults over 55 years of age with a rash of less than 7 days duration, and severe pain due to HZ, were enrolled and randomized to receive either intravenous acyclovir (10 mg/kg three times daily) for 9 days+prednisolone (60 mg per day with progressive reduction) for 21 days, or 6-12 ml bupivacaine (0.25%) every 6-8 or 12 h+methylprednisolone 40 mg every 3-4 days by epidural catheter during a period ranging from 7 to 21 days. Efficacy was evaluated at 1, 3, 6 and 12 months. PHN was assessed as pain and/or allodynia, and "abnormal sensations" (hypoesthesia, burning, itching, etc.). Statistical analysis was performed based on the intent-to-treat population. RESULTS: In the 485 patients who completed the study, the incidence of pain after 1 year was 22.2% (51 patients of 230) after acyclovir+steroids, and 1.6% (4 patients of 255) after epidural analgesia+steroids. The incidence of abnormal sensations was 12.2% (28 patients) after acyclovir+steroids, and 4.3% (11 patients) in group B. CONCLUSIONS: Epidural administration of local anesthetic and methylprednisolone is significantly more effective in preventing PHN at 12 months compared to intravenous acyclovir and prednisolone.