The impact of carbon dioxide pneumoperitoneum on liver regeneration after liver resection in a rat model. Surg Endosc. 2010;24:1-8. [PMID: 19533243 DOI: 10.1007/s00464-009-0536-x]

Impact of laparoscopic liver resection on liver regeneration

BACKGROUND

Liver regeneration after liver resection plays an important role in preventing posthepatectomy liver failure. In this study, we aimed to evaluate and compare the impact of laparoscopic liver resection (LLR) and open liver resection (OLR) on liver regeneration.

METHODS

Patients who underwent curative anatomical liver resection for hepatocellular carcinoma, cholangiocellular carcinoma, and colorectal liver metastases at our institution between January 2010 and December 2018 were included in this study. The patients were divided into the OLR and LLR groups. Preoperative liver volume (PLV), future remnant liver volume, resected liver volume (RLV), liver volume at 1 month after the surgery, and liver volume at 6 months after the surgery were calculated. The liver regeneration rate was defined as the increase in the rate of RLV, and the liver recovery rate was defined as the rate of return to the PLV.

RESULTS

The study included 72 patients. Among them, 43 were included in the OLR group and 29 were included in the LLR group. No differences were observed in the baseline characteristics and surgical procedures between the two groups. Moreover, no significant difference was observed in the liver regeneration rate at 1 month after the surgery (OLR vs. LLR: 68.9% vs. 69.0%, p = 0.875) and at 6 months after the surgery (91.8% vs. 93.2%, p = 0.995). Furthermore, the liver recovery rates were not significantly different between the two groups at 1 month after the surgery (90.3% vs. 90.6%, p = 0.893) and at 6 months after the surgery (96.9% vs. 98.8%, p = 0.986).

CONCLUSION

Liver regeneration after liver resection is not affected by the type of surgical procedure and both laparoscopic and open procedures yield similar regeneration and recovery rates.

Effect of laparoscopic liver resection versus the open technique on hepatocyte regenerating activity in the rat

BACKGROUND

Laparoscopic liver resection offers a safe and feasible option primarily for the excision of hepatic neoplasms. Timely recovery of liver volume is a key factor for improving prognosis and post-operative mortality of patients undergone liver resection. The aim of the present study was to compare liver regeneration after laparoscopic over open partial hepatectomy.

METHODS

Wistar rats were subjected to laparoscopic 70% hepatectomy (group LAP-HEP), open 70% hepatectomy (group HEP), sham operation (group Sham) or no intervention (group Control). At various timepoints following operation (1 h-2 weeks), the liver was excised to assess relative liver weight, thiobarbituric acid reactive substances (TBARS) levels, mitotic activity, tissue expression of Nuclear Factor-κB (NFκB), Intercellular Adhesion Molecule-1 (ICAM-1) and Vascular Cell Adhesion Molecule-1 (VCAM-1) and the histopathologic profile.

RESULTS

No differences were seen in relative liver weight between hepatectomy groups. Mitotic index was increased in all operative study groups, being higher in group LAP-HEP than in group HEP. TBARS levels were higher in group LAP-HEP compared to group HEP. NFκB and VCAM-1 tissue expression scores were increased in all operative study groups with VCAM-1 being higher in group HEP, while ICAM-1 was overexpressed only in hepatectomy groups. Mild histopathologic lesions were noted in hepatectomy groups with the histopathologic score being higher in group HEP (24 h).

CONCLUSIONS

Laparoscopic liver resection enhanced hepatocyte mitotic activity which was accompanied by mild oxidative stress and a less pronounced local inflammatory response and tissue injury to that of the open technique.

Postoperative immunosuppression after open and laparoscopic liver resection: assessment of cellular immune function and monocytic HLA-DR expression

In an experimental setting, the authors demonstrated a trend toward improved preservation of the immune system after laparoscopic hepatic resection compared with open surgery.

Background and Objectives:

Major abdominal procedures are strongly associated with postoperative immunosuppression and subsequent increased patient morbidity. It is believed that laparoscopic surgery causes less depletion of the systemic immune function because of the reduced tissue trauma. Various cytokines and monocytic HLA-DR expression have been successfully implemented to assess postoperative immune function. The aim of our study was to show the difference in immunologic profiles after minimally invasive versus conventional liver resection.

Methods:

Ten animals underwent either laparoscopic or conventional open left lateral liver resection. Flow cytometric characteristics of HLA-DR expression on monocytes and lipopolysaccharide-stimulated cellular secretion of tumor necrosis factor α, interferon γ, interleukin 6, and interleukin 8 were measured and analyzed in ex vivo whole blood samples. Intraoperative and postoperative clinical outcome parameters were also documented and evaluated.

Results:

All animals survived the procedures. Postoperative complications were fever (n = 3), wound infections (n = 2), and biloma (n = 1). Open surgery showed a morbidity rate of 80% compared with 40% after laparoscopic surgery. Laparoscopic liver resection showed no postoperative immunoparalysis. Major histocompatibility complex class II expression in this group was elevated, whereas the open surgery group showed decreased major histocompatibility complex class II expression on postoperative day 1. Postoperative secretion of tumor necrosis factor α, interleukin 6, and interferon γ was lower in the open surgery group. Elevated transaminase levels after laparoscopy might have resulted from an ischemia/reperfusion injury caused by the capnoperitoneum.

Conclusion:

Major immunoparalysis depression was not observed in either group. Laparoscopic surgery shows a tendency to improve immunologic recovery after liver resection.

Effects of different pressure levels of CO2 pneumoperitoneum on liver regeneration after liver resection in a rat model

BACKGROUND

A recent study demonstrated that high pressure of carbon dioxide (CO2) pneumoperitoneum before liver resection impairs postoperative liver regeneration. This study was aimed to investigate effects of varying insufflation pressures of CO2 pneumoperitoneum on liver regeneration using a rat model.

METHODS

180 male Wistar rats were randomly divided into three groups: control group (without preoperative pneumoperitoneum), low-pressure group (with preoperative pneumoperitoneum at 5 mmHg), and high-pressure group (with preoperative pneumoperitoneum at 10 mmHg). After pneumoperitoneum, all rats were subjected to 70% partial hepatic resection and then euthanized at 0 min, 12 h, and on postoperative days (PODs) 1, 2, 4, and 7. Following outcome parameters were used: liver regeneration (liver regeneration rate, mitotic count, Ki-67 labeling index), hepatocellular damage (serum aminotransferases), oxidative stress [serum malondialdehyde (MDA)], interleukin-6 (IL-6), and hepatocyte growth factor (HGF) expression in the liver tissue.

RESULTS

No significant differences were observed for all parameters between control and low-pressure groups. The liver regeneration rate and mitotic count were significantly decreased in the high-pressure group than in control and low-pressure groups on PODs 2 and 4. Postoperative hepatocellular damage was significantly greater in the high-pressure group on PODs 1, 2, 4, and 7 compared with control and/or low-pressure groups. Serum MDA levels were significantly higher in the high-pressure group on PODs 1 and 2, and serum IL-6 levels were significantly higher in the high-pressure group at 12 h and on POD 1, compared with control and/or low-pressure groups. The HGF tissue expression was significantly lower in the high-pressure group at 12 h and on PODs 1 and 4, compared with that in control and/or low-pressure groups.

CONCLUSIONS

High-pressure pneumoperitoneum before 70% liver resection impairs postoperative liver regeneration, but low-pressure pneumoperitoneum has no adverse effects. This study suggests that following laparoscopic liver resection using appropriate pneumoperitoneum pressure, no impairment of liver regeneration occurs.

Risk factors and management of conversions to an open approach in laparoscopic liver resection: analysis of 265 consecutive cases

BACKGROUND

As a consequence of continuous technical developments in liver surgery, laparoscopic liver resection (LLR) is increasingly performed worldwide.

METHODS

Between January 2004 and December 2011, 265 LLR were performed in 242 patients for various diseases. The experience of LLR is reported focusing on risk factors of conversion and their management.

RESULTS

The overall conversion rate was 17/265 (6.4%), equally distributed over the period of the study. Statistically significant factors for conversion were found to be LLR of the postero-superior (P-S) segments (SI, SIVa; SVII; SVIII) (12.7% converted versus 2.5% non-converted groups, P = 0.01) and a major compared with a minor hepatectomy (15.2% vs. 4.6%, P = 0.02 respectively). A R0 resection was achieved in 93.2% of cases. According to Dindo's classification, complications were recorded as grade I (n = 20); grade II (6); grade III (11) and grade IV(1) events (total morbidity rate of 14%). Univariate analysis identified a major hepatectomy and resection involving P-S segments as prognostic factors for conversion whereas multivariate analysis identified the latter as an independent risk factor [P = 0.003, odds ratio (OR) = 5.9, 95% confidence interval (CI) = 1.8-18.8].

CONCLUSIONS

LLR can be safely performed with low overall morbidity. According to this experience and irrespective of the learning curve, resections of P-S segments were identified as an independent risk factor for conversion in LLR.

Lentiviral-mediated delivery of shRNA targeting the SMAD3 gene promotes liver regeneration in rats

AIM: To investigate the effect of lentiviral-mediated delivery of shRNA targeting the SMAD3 gene on liver regeneration in rats.

METHODS: Sixty male rats were randomly divided into three groups: SMAD3 shRNA group (n = 20), shRNA control group (n = 20), and normal saline group (n = 20). Intrasplenic injection of lentivirus carrying the SMAD3 shRNA or control shRNA at a dose of 1.0 × 10⁸ TU per rat was performed in rats of the SMAD3 shRNA group and shRNA control group, respectively, while the normal saline group was given equal volume of normal saline. After 96 h, 2/3 partial hepatectomy was performed to develop a rat model of liver regeneration. Seven rats of each group were sacrificed at 96 h, and the rest were sacrificed at 144 h after hepatectomy. Liver tissue specimens were collected. SMAD3 expression was detected using real-time PCR and immunohistochemistry. Proliferation of hepatocytes was evaluated by detecting Ki67 by immunohistochemistry. The ratio of liver weight to body weight was determined to observe its role in liver regeneration in vivo.

RESULTS: At 96 h and 144 h after hepatectomy, SMAD3 mRNA expression decreased by 73% and 63% in the SMAD3 shRNA group compared to the shRNA control group. The expression of SMAD3 protein also decreased obviously. More active proliferation of hepatocytes was observed after SMAD3 down-regulation. The liver weight/body weight in the SMAD3 shRNA group was higher than those in the normal saline control group and shRNA control group (96 h: 4.50 ± 0.43 vs 3.97 ± 0.55 vs 3.98 ± 0.40, 144 h: 4.66 ± 0.54 vs 4.15 ± 0.51 vs 4.20 ± 0.34), but there was no statistically significance between them (all P > 0.05).

CONCLUSION: Down-regulation of SMAD3 expression could moderately promote liver regeneration in rats.

Effects of carbon dioxide pneumoperitoneum on hepatic and renal morphology of rats after segmental colectomy and colonic anastomosis

PURPOSE

To evaluate the effects of increased intraperitoneal pressure caused by carbon dioxide pneumoperitoneum on the hepatic and renal morphology of rats.

METHODS

Fifty-four adult male rats were randomly divided into three groups (P, PP and C) after anesthesia: P - in 18 animals, pneumoperitoneum was established for 30 minutes immediately before laparotomy; PP - in 18 animals, pneumoperitoneum was established for 60 minutes divided into 30 immediately before laparotomy and 30 after abdominal closure; control group (C) - 18 animals underwent laparotomy without pneumoperitoneum induction. The pneumoperitoneum was maintained at a pressure of 5 mm Hg. Nine animals in each group were killed on the 3(rd) and 7(th) postoperative days, when kidney and liver samples were collected for morphological analysis. The liver specimens were stained with hematoxylin and eosin (HE), and the kidney specimens, with HE and von Kossa. Blinded examiners analyzed the slides.

RESULTS

No changes in renal morphology were found. Liver samples showed histological signs of degeneration in animals in the pneumoperitoneum groups killed on the 7(th) postoperative day (p=0.029).

CONCLUSION

The CO(2) pneumoperitoneum did not affect renal morphology but caused hydropic degeneration in the liver of animals killed on the 7(th) postoperative day.

Transplantation of porcine hepatocytes cultured with polylactic Acid-o-carboxymethylated chitosan nanoparticles promotes liver regeneration in acute liver failure rats

In this study, free porcine hepatocytes suspension (Group A), porcine hepatocytes embedded in collagen gel (Group B), porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel (Group C), and PLA-O-CMC nanoparticles alone (Group D) were transplanted into peritoneal cavity of ALF rats, respectively. The result showed that plasma HGF levels were elevated post-transplantation with a peak at 12 hr. The rats in Group C showed highest plasma HGF levels at 2, 6, 12, 24 and 36 hr post-transplantation and lowest HGF level at 48 hr. Plasma VEGF levels were elevated at 48 hr post-transplantation with a peak at 72 hr. The rats in Group C showed highest plasma HGF levels at 48, 72, and 96 hr post-transplantation. The liver functions in Group C were recovered most rapidly. Compared with Group B, Group C had significant high liver Kiel 67 antigen labeling index (Ki-67 LI) at day 1 post-HTx (P < .05). Ki-67 LI in groups B and C was higher than that in groups A and D at days 5 and 7 post-HTx. In conclusion, intraperitoneal transplantation of porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel can promote significantly liver regeneration in ALF rats.