The effect of preconditioning on liver regeneration after hepatic resection in cirrhotic rats

Liver ischemia-reperfusion injury: From trigger loading to shot firing

An ischemia-reperfusion injury (IRI) results from a prolonged ischemic insult followed by the restoration of blood perfusion, being a common cause of morbidity and mortality, especially in liver transplantation. At the maximum of the potential damage, IRI is characterized by 2 main phases. The first is the ischemic phase, where the hypoxia and vascular stasis induces cell damage and the accumulation of damage-associated molecular patterns and cytokines. The second is the reperfusion phase, where the local sterile inflammatory response driven by innate immunity leads to a massive cell death and impaired liver functionality. The ischemic time becomes crucial in patients with underlying pathophysiological conditions. It is possible to compare this process to a shooting gun, where the loading trigger is the ischemia period and the firing shot is the reperfusion phase. In this optic, this article aims at reviewing the main ischemic events following the phases of the surgical timeline, considering the consequent reperfusion damage.

Early predictor of mortality due to irreversible posthepatectomy liver failure in patients with hepatocellular carcinoma

BACKGROUND

Although mortality after liver resection has declined, posthepatectomy liver failure (PHLF) remains a major cause of operative mortality. To date there is not consensus on a definition for PHLF. However, there have been many efforts to define PHLF causing operative mortality. In the present study we sought to identify early predictors of death from irreversible PHLF.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 359 patients with hepatocellular carcinoma who underwent liver resection between March 2000 and December 2010. Various biochemical parameters from postoperative days (POD) 1, 3, 5, and 7 were analyzed and compared with the "50-50" criterion.

RESULTS

Operative mortality was 4.7 %. Prothrombin time (PT) <65 % and bilirubin ≥ 38 μmol/L on POD 5 showed the only significant difference as compared with "50-50" criterion. The new combination of bilirubin level and the international normalized ratio showed higher sensitivity, area under the curve, as well as similar accuracy (sensitivity 78.6 vs. 28.6 %; p = 0.002; area under the curve 0.8402 vs. 0.6396; p = 0.00176; accuracy 88.6 vs. 93.4 %; p = 0.090). Multivariate analysis revealed the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 to be the only independent predictive factor of mortality (odds ratio, 82.29; 95 % confidence interval 8.69-779.64; p < 0.001).

CONCLUSIONS

In patients with chronic liver disease who will undergo liver resection the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 may be a more sensitive predictor than the "50-50" criterion of mortality from PHLF. Although it needs to validated by prospective study, this measure may be applied to select patients receiving artificial liver supports or liver transplantation.

Parenteral solution of nutritional hepatotrophic factors improves regeneration in thioacetamide-induced cirrhotic livers after partial hepatectomy

Liver resection is a suitable option for the treatment of certain hepatic conditions, particularly hepatocarcinomas, in patients with cirrhosis. However, this disease impairs liver regeneration, which increases the risk of liver failure and postoperative death. Supportive treatments for regeneration of the remaining liver may be useful for the recovery of these patients. We demonstrated that nutritional hepatotrophic factors (NHF) is an effective regenerative stimulus for cirrhotic livers in rats subjected to partial hepatectomy (PH). The rats with thioacetamide-induced cirrhosis were subjected to PH, and they were divided into 2 groups. One group received intraperitoneal administration of NHF, and the other group received saline solution. After 12 days, biometric data, collagen content, hepatocyte regeneration (proliferation cell nuclear antigen immunochemistry), and profibrotic gene expression (Collagen-α1, matrix metalloproteinase 2, tissue inhibitor of metalloproteinase 1, and transforming growth factor beta 1) were assessed. The results indicated that the rats treated with NHF after PH had an increased liver size, a reduced amount of collagen, and a higher hepatocyte proliferation index compared with the rats that underwent PH alone. In addition, collagen-α1 gene expression was decreased in the NHF-treated rats. Thus, postoperative improvement in the liver morphology following NHF treatment may cause a significant decrease in the risk of liver failure and mortality after hepatic resection.