Ischemic injury in cirrhotic livers: an experimental study of the temporary arrest of hepatic circulation

Inflow control can be safely used in laparoscopic subsegmentectomy of the liver: a single-center 10-year experience

BACKGROUND

Several techniques have been developed to reduce blood loss in liver resection. The half-Pringle and Pringle maneuvers are commonly used for inflow control. This study compared the outcomes of different inflow control techniques in laparoscopic subsegmentectomy.

METHODS

From October 2010 to December 2020, a total of 362 laparoscopic liver resections were performed by a single surgeon (C.C. Yong) in our institute. We retrospectively enrolled 133 patients who underwent laparoscopic subsegmentectomy during the same period. Perioperative and long-term outcomes were analyzed.

RESULTS

The 133 patients were divided into 3 groups: no inflow control (n = 49), half-Pringle maneuver (n = 46), and Pringle maneuver (n = 38). A lower proportion of patients with cirrhosis were included in the half-Pringle maneuver group (P = .02). Fewer patients in the half-Pringle maneuver group had undergone previous abdominal (P = .01) or liver (P = .02) surgery. The no inflow control group had more patients with tumors located in the anterolateral segments (P = .001). The no inflow control group had a shorter operation time (P < .001) and less blood loss (P = .03). The need for blood transfusion, morbidity, and hospital days did not differ among the 3 groups. The overall survival did not significantly differ among the 3 groups (P = .89).

CONCLUSIONS

The half-Pringle and Pringle maneuvers did not affect perioperative or long-term outcomes during laparoscopic subsegmentectomy. The inflow control maneuvers could be safely performed in laparoscopic subsegmentectomy.

How much ischemia can the liver tolerate during resection?

The use of vascular inflow occlusion (VIO, also known as the Pringle maneuver) during liver surgery prevents severe blood loss and the need for blood transfusion. The most commonly used technique for VIO entails clamping of the portal triad, which simultaneously occludes the proper hepatic artery and portal vein. Although VIO is an effective technique to reduce intraoperative blood loss, it also inevitably inflicts hepatic ischemia/reperfusion (I/R) injury as a side effect. I/R injury induces formation of reactive oxygen species that cause oxidative stress and cell death, ultimately leading to a sterile inflammatory response that causes hepatocellular damage and liver dysfunction that can result in acute liver failure in most severe cases. Since the duration of ischemia correlates positively with the severity of liver injury, there is a need to find the balance between preventing severe blood loss and inducing liver damage through the use of VIO. Although research on the maximum duration of hepatic ischemia has intensified since the beginning of the 1980s, there still is no consensus on the tolerable upper limit. Based on the available literature, it is concluded that intermittent and continuous VIO can both be used safely when ischemia times do not exceed 120 min. However, intermittent VIO should be the preferred technique in cases that require >120 min duration of ischemia.

Is there any benefit from expanding the criteria for the resection of hepatocellular carcinoma in cirrhotic liver? Experience from a developing country

BACKGROUND

Patients with large-size (>10 cm) hepatocellular carcinoma (HCC) in Child B cirrhosis are usually excluded from curative treatment, i.e., hepatic resection, because of marginal liver function and poor outcome. This study was designed to evaluate the feasibility of the radiofrequency (RF)-assisted sequential "coagulate-cut liver resection technique" in expanding the criteria for resection of large HCC in cirrhotic livers with impaired liver function.

METHODS

Forty patients with Child-Pugh A or B cirrhosis underwent liver resection from December 1, 2001 to December 31, 2008. Of these, 20 patients (13 Child-Pugh A and 7 Child-Pugh B) with advanced stage HCC (stage B and C according to Barcelona-Clinic Liver Cancer Group) underwent major liver resection. The two groups were comparable in terms of patient age, liver cirrhosis etiology, tumor number, and size.

RESULTS

All resections were performed without the Pringle maneuver. There was no significant difference found between the two groups regarding resection time, perioperative transfusion, postoperative complications, hospital stay, and day 7 values of hemoglobin and liver enzymes. Likewise, there was no significant difference found in the overall survival between Child A and Child B patients who underwent major liver resection

CONCLUSIONS

RF-assisted sequentional "coagulate-cut liver resection technique" may be a viable alternative for management of patients with advanced HCC in cirrhotic liver with impaired function.

Pretreatment with intrathecal or intravenous morphine attenuates hepatic ischaemia-reperfusion injury in normal and cirrhotic rat liver

BACKGROUND

Opioids have been shown to attenuate ischaemia-reperfusion injury (IRI) in a number of organs. We evaluated the effect of morphine pretreatment on IRI in both normal and cirrhotic rat liver.

METHODS

Morphine was administered either i.v. or intrathecally (i.t.) 10 min before initiating 1 h of ischaemia followed by 6 h reperfusion in normal rat liver. Hepatic injury was assessed histologically using Suzuki's criteria. These manoeuvres were repeated using the optimal dose of morphine after administration of naloxone methiodide and wortmannin. Serum levels of transaminases were measured, and expression of phosphorylated Akt, Jak2, and STAT3 were assessed by immunoblotting. Similar procedures were repeated on rats with carbon tetrachloride-induced liver cirrhosis, and the levels of phosphorylated protein kinase C (PKC), haem oxygenase-1 (HO-1), and inducible nitric oxide synthase (iNOS) were also evaluated, as these proteins have beneficial effects during IRI.

RESULTS

Morphine pretreatment at 100 µg kg(-1) (i.v.) or 10 µg (i.t.) reduced necrosis, apoptosis, and serum transaminase levels, and increased phosphorylated Akt and STAT3 but not JAK2 expression in normal liver. These changes were reversed by prior administration of naloxone methiodide and wortmannin. Although morphine preconditioning was also protective in cirrhotic liver, STAT3 and JAK2 phosphorylation status was unchanged. There was, however, increased expression of phosphorylated PKC and HO-1, and a reduction in iNOS.

CONCLUSIONS

Morphine preconditioning protects against IRI in both normal and cirrhotic rat liver. This involves opioid receptors, phosphatidylinositol-3-kinase, and Akt. The downstream pathways involved are different for cirrhotic liver, with preliminary evidence suggesting involvement of HO-1.

Hemihepatic versus total hepatic inflow occlusion during hepatectomy: A systematic review and meta-analysis

AIM: To evaluate the clinical outcomes of patients undergoing hepatectomy with hemihepatic vascular occlusion (HHO) compared with total hepatic inflow occlusion (THO).

METHODS: Randomized controlled trials (RCTs) comparing hemihepatic vascular occlusion and total hepatic inflow occlusion were included by a systematic literature search. Two authors independently assessed the trials for inclusion and extracted the data. A meta-analysis was conducted to estimate blood loss, transfusion requirement, and liver injury based on the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Either the fixed effects model or random effects model was used.

RESULTS: Four RCTs including 338 patients met the predefined inclusion criteria. A total of 167 patients were treated with THO and 171 with HHO. Meta-analysis of AST levels on postoperative day 1 indicated higher levels in the THO group with weighted mean difference (WMD) 342.27; 95% confidence intervals (CI) 217.28-467.26; P = 0.00 001; I² = 16%. Meta-analysis showed no significant difference between THO group and HHO group on blood loss, transfusion requirement, mortality, morbidity, operating time, ischemic duration, hospital stay, ALT levels on postoperative day 1, 3 and 7 and AST levels on postoperative day 3 and 7.

CONCLUSION: Hemihepatic vascular occlusion does not offer satisfying benefit to the patients undergoing hepatic resection. However, they have less liver injury after liver resections.

Effects of intermittent Pringle's manoeuvre on cirrhotic compared with normal liver

BACKGROUND

Although patients with liver cirrhosis are supposed to tolerate ischaemia-reperfusion poorly, the exact impact of intermittent inflow clamping during hepatic resection of cirrhotic compared with normal liver remains unclear.

METHODS

Intermittent Pringle's manoeuvre was applied during minor hepatectomy in 172 patients with a normal liver, 59 with chronic hepatitis and 97 with liver cirrhosis. To assess hepatic injury, delta (D)-aspartate aminotransferase (AST) and D-alanine aminotransferase (ALT) (maximum level minus preoperative level) were calculated. To evaluate postoperative liver function, postoperative levels of total bilirubin, albumin and cholinesterase (ChE), and prothrombin time were measured.

RESULTS

Significant correlations between D-AST or D-ALT and clamping time were found in each group. The regression coefficients of the regression lines for D-AST and D-ALT in patients with normal liver were significantly higher than those in patients with cirrhotic liver. Irrespective of whether clamping time was 45 min or less, or at least 60 min, D-AST and D-ALT were significantly lower in patients with cirrhosis than in those with a normal liver. Parameters of hepatic functional reserve, such as total bilirubin, prothrombin time, albumin and ChE, were impaired significantly after surgery in patients with a cirrhotic liver.

CONCLUSION

Patients with liver cirrhosis had a smaller increase in aminotransferase levels following portal triad clamping than those with a normal liver. However, hepatic functional reserve in those with a cirrhotic liver seemed to be affected more after intermittent inflow occlusion.

Outcome using hemihepatic vascular occlusion versus the pringle maneuver in resections limited to one hepatic section or less

Consensus is lacking concerning how to manage afferent vessels during hepatectomy, particularly as to the Pringle maneuver vs. selective hemihepatic clamping. Data for 81 hepatocellular carcinoma patients with chronic hepatitis or liver cirrhosis whose liver resection was limited to one section or less, including intraoperative data and postoperative liver function data, were analyzed retrospectively to compare two strategies. No significant differences of intraoperative data or postoperative clinical course were seen between the two groups, even in patients with chronic hepatitis or liver cirrhosis whose postoperative deterioration of liver function could be expected to be more than patients with a normal liver. The difference was evident only in serum alanine aminotransferase level on postoperative day 10 (mean +/- SEM, 64.5 +/- 5.1 IU in the Pringle group vs. 51.6 +/- 4.4 IU in the selective clamping group; P < 0.05). During liver resection limited to one section or less, even with underlying chronic hepatitis or cirrhosis, intermittent use of the Pringle maneuver preserved liver function to the same extent as selective clamping.

FTY720 attenuates hepatic ischemia-reperfusion injury in normal and cirrhotic livers

Hepatic ischemia-reperfusion injury is an inevitable consequence during liver surgery. The outcome is particularly poor in cirrhotic livers, which are more prone to hepatic ischemia-reperfusion injury. We aim to study whether FTY720 could attenuate hepatic ischemia-reperfusion injury both in normal and in cirrhotic livers. We applied a 70% liver-ischemia (60 min) model in rats with normal or cirrhotic livers. FTY720 was given 20 min before ischemia and 10 min before reperfusion (1 mg/kg, i.v.). Liver tissues and blood were sampled at 20 min, 60 min, 90 min, 6 h and 24 h after reperfusion for detection of MAPK-Egr-1, Akt pathways and caspase cascade. Hepatic ultrastructure and apoptosis were also compared. FTY720 significantly improved liver function in the rats with normal and cirrhotic livers. Akt pathway was activated at 6 and 24 h after reperfusion. FTY720 significantly down-regulated Egr-1, ET-1, iNOS and MIP-2 accompanied with up-regulation of A20, IL-10, HO-1 and Hsp70. MAPK (Raf-MEK-Erk) pathway was down-regulated. Hepatic ultrastructure was well maintained and fewer apoptotic liver cells were found in the FTY720 groups. In conclusion, FTY720 attenuates ischemia-reperfusion injury in both normal and cirrhotic livers by activation of cell survival Akt signaling and down-regulation of Egr-1 via Raf-MEK-Erk pathway.

Isquemia hepática normotérmica em ratos: estudo da lesão celular através do uso de clampeamento pedicular contínuo e intermitente

OBJETIVO: Avaliar as alterações bioquímicas decorrentes da isquemia hepática normotérmica, seguida de reperfusão em duas modalidades de clampeamento da tríade portal em ratos. MÉTODO: Trinta ratos Wistar machos pesando entre 250 e 320 gramas foram divididos em três grupos de 10 animais cada. Induzimos 40 minutos de isquemia hepática por clampeamento pedicular contínuo (grupo I) ou intermitente (grupo II). No grupo controle não houve clampeamento. Como parâmetro de lesão hepatocelular adotamos a concentração plasmática de: transaminase glutâmico oxalacética (TGO), transaminase glutâmico pirúvica (TGP) e lactato desidrogenase (LDH). Colhemos as amostras de sangue no início (T1) e no final da cirurgia (T2). Todos os animais foram submetidos ao mesmo tempo operatório: 60 minutos. RESULTADOS: Não houve diferença estatística nos valores iniciais (T1) das três enzimas nos três grupos. Todos apresentaram aumento significativo das enzimas do momento 1 (T1) para o momento 2 (T2). Houve diferença estatística no aumento médio de TGO e TGP entre os três grupos, sendo o maior aumento encontrado no grupo I e o menor, no grupo controle. Não houve diferença significativa, em relação à LDH, entre o grupo II e o grupo controle. No grupo I, entretanto, houve aumento significativo em relação aos demais. Conclusão: Comparado ao clampeamento contínuo, para um período total de 40 minutos de isquemia, o clampeamento da tríade portal em ratos realizado de forma intermitente, com ciclos de 10 minutos de isquemia e 5 minutos de reperfusão, provoca menor dano hepatocelular, o que foi constatado pela menor alteração enzimática.

N-acetilcisteína diminui a congestão hepática na lesão de isquemia e reperfusão: estudo experimental

OBJETIVOS: A isquemia tem sido utilizada na cirurgia hepática desde o início do século. Embora possibilite a diminuição da perda sangüínea durante as ressecções e a manutenção do órgão à espera de um transplante, a ausência de perfusão traz como conseqüência um dano ao órgão, que se amplifica por ocasião da sua reoxigenação. A N-Acetilcisteína é uma droga capaz de repor os estoques celulares de glutationa, um antioxidante fundamental no controle das lesões resultantes do restabelecimento da perfusão sangüínea, esperando-se dessa forma que diminua a lesão acima descrita. Com o propósito de avaliar a capacidade da N-Acetilcisteína reduzir o dano hepático, utilizou-se um modelo murino de isquemia e reperfusão normotérmica. MÉTODO: Foram utilizados vinte ratos Wistar fêmeas, divididos em dois grupos. No grupo tratado, 400mg/kg de N-Acetilcisteína foram administrados pela via intravenosa, 15 minutos antes do clampeamento do pedículo do lobo esquerdo por 90 minutos. No grupo controle foi administrado o volume equivalente de solução fisiológica. Foi estabelecido um período de quatro horas de reperfusão, após o qual os animais foram sacrificados para a realização de análise histopatológica do lobo esquerdo com coloração de Hematoxilina-Eosina. A lesão tecidual foi quantificada quanto à presença de congestão, esteatose e necrose. RESULTADOS: O estudo evidenciou a capacidade de a N-Acetilcisteína diminuir significativamente a congestão. Não houve diferenças quanto à presença de esteatose e necrose. CONCLUSÃO: Os resultados obtidos permitem-nos concluir que o uso prévio da N-Acetilcisteína nos processos de isquemia e reperfusão, em normotermia, é capaz de diminuir a congestão hepática. A N-Acetilcisteína não diminui a presença de esteatose e necrose.

Blunted anti-inflammatory response to adenosine in alcoholic cirrhosis

BACKGROUND/AIM

Adenosine is an endogenous nucleoside that is released under metabolically unfavourable circumstances such as ischaemia or infection. It exerts potent anti-inflammatory effects by decreasing tumour necrosis factor release and costimulating interleukin-10 production by human monocytes. The aim of this study was to assess the cytokine response to adenosine in whole blood cultures from alcoholic cirrhotic patients.

METHODS

Whole blood from 17 patients and 17 healthy controls stimulated with lipopolysaccharide was cultured in the presence of adenosine at different concentrations and, in some experiments, with the adenosine deaminase inhibitor deoxycoformycin. Peripheral blood mononuclear cell response was compared to whole blood, and plasma adenosine deaminase activity was measured.

RESULTS

Adenosine (100 microM) significantly inhibited TNF release and increased IL-10 production in whole blood cultures from controls stimulated with lipopolysaccharide, but not from cirrhotic patients. However, the response to adenosine was restored in peripheral mononuclear cells of patients in the absence of autologous plasma. To test the hypothesis that plasma adenosine deaminase, which was increased in the patients' plasma, was actually involved in this blunted response to adenosine in alcoholic cirrhosis, we performed adenosine dose-response experiments and pharmacologically blocked adenosine deaminase activity with deoxycoformycin. In both kinds of experiment, adenosine-induced inhibition of TNF release could be restored in alcoholic cirrhotic patients.

CONCLUSIONS

These data indicate that increased circulating adenosine deaminase activity blunts the anti-inflammatory properties of adenosine in alcoholic cirrhotic patients.

Normothermic liver ischemia and antioxidant treatment during hepatic resections

The purpose of our study was to evaluate the clinical impact of reperfusion injury after normothermic ischemia during major liver resections and the effect of an intraoperative antioxidant infusion. This prospective randomized study comprised 50 patients; half of them (treatment group) were given an antioxidant infusion containing tocopherol and ascorbate immediately prior to reperfusion onset. Venous blood samples for the determination of MDA-TBARS (malondialdehyde-thiobarbituric acid reactive substances) by a HPLC-based test as a marker of lipid peroxidation were taken prior to ischemia, 30 min after reperfusion onset and at the end of the operation. In the control group there was a significant increase of MDA-TBARS (p = 0.001) at 30 min after reperfusion onset. At the end of the operation the values had returned to the initial level. The treatment group showed only a marginal increase (p-value for the difference between the two groups: 0.007). After exclusion of the patients with histologically proven advanced cirrhosis the increase in the control group (p < 0.001) and the difference between the increase in the two groups (p = 0.001) became more significant. Prothrombin time was also significantly better in the treatment group (p = 0.003). Postoperative complications such as prolonged liver failure, bleeding disorders and infections were seen more often in the control group. In our study MDA-TBARS was increased after liver ischemia, but in patients with advanced cirrhosis the effect was smaller or even absent. This increase and possible clinical consequences of reperfusion injury could be reduced by intraoperative administration of an antioxidant infusion.

Effects and limitations of prolonged intermittent ischaemia for hepatic resection of the cirrhotic liver

Intermittent clamping of the hepatic pedicle during hepatectomy may reduce operative bleeding, but its limitations and long-term effects on the cirrhotic liver are unknown. Eighty-three patients with cirrhosis undergoing hepatectomy with repeated clamping for 15 min and declamping for 5 min were divided into three groups based on total clamping duration: group 1 less than 40 min (39 patients); group 2 40-80 min (28); group 3 more than 80 min (16). Larger tumours were associated with longer ischaemia times (P = 0.002), longer operating times, greater operative blood loss and increased blood transfusion requirements (P < 0.001), and resulted in higher postoperative levels of serum transaminases and lactic dehydrogenase (P < 0.001). Operative morbidity and mortality rates, and the late hepatic failure rate, were not affected. The longest total ischaemia time was 204 min but the uppermost time limit for hepatic ischaemia remains to be determined.