Does arterialisation time influence biliary tract complications after orthotopic liver transplantation?

Impact of recombinant globular adiponectin on early warm ischemia-reperfusion injury in rat bile duct after liver transplantation

Adiponectin (APN) is an adipocyte protein with anti-diabetic properties, which has been recently revealed to have anti-inflammatory activity in organ ischemia- reperfusion injury (IRI). However, little is known about its function in bile duct IRI after liver transplantation. Therefore, we investigated whether APN affects early warm IRI in rat bile duct using a liver autologous transplantation model. In our study, rats were randomly divided into three experimental groups: a sham group, a IRI group, and a APN group. The serum enzyme levels and BDISS scores of bile duct histology associated with bile duct injury, decreased after administration of APN. Subsequently, the expression of proinflammatory cytokines, such as tumor necrosis factor(TNF-α),.interleukin-6(IL-6) and myeloperoxidase (MPO) decreased. Furthermore, pretreatment with APN suppressed the activation of nuclear factor-kappa B (NF-κB) (p65), a transcription factor involved in inflammatory reactions, compared to other two groups. Administration of APN also downregulated the expression of Fas protein and attenuated caspase-3 activity to decrease bile duct apoptosis. Our results illustrate that APN protects the rat bile duct against early warm IRI by suppressing the inflammatory response and hepatocyte apoptosis, and NF-κB (p65) plays an important role in this process.

Timing of hepatic artery reperfusion and biliary strictures in liver transplantation

During orthotopic liver transplantation (OLT), biliary tract perfusion occurs with hepatic artery reperfusion (HARP), commonly performed after the portal vein reperfusion (PVRP). We examined whether the average time interval between PVRP and HARP impacted on postoperative biliary strictures occurrence. Patients undergoing OLT from 2007 to 2009 were included if they were ≥18 years old, had survived 3 months postoperatively, and had data for PVRP and HARP. Patients receiving allografts from DCD donors were excluded. Patients were followed for 6 months post-OLT. Seventy-five patients met the study inclusion criteria. Of these, 10 patients had a biliary stricture. There was no statistical difference between those with and without biliary stricture in age, gender, etiology, MELD score, graft survival, and time interval between PVRP and HARP. Ninety percent of patients with biliary stricture had a PVRP-HARP time interval >30 minutes, as opposed to 77% of patients without biliary stricture. However, this was not statistically significant. The cold ischemia time was significantly different between the two groups. Time interval for HARP after PVRP did not appear to affect the development of biliary strictures. However, 30 minutes may be suggested as a critical time after which there is an increase in biliary stricture occurrence.

The influence of a contemporaneous portal and hepatic artery revascularization protocol on biliary complications after liver transplantation

BACKGROUND

We sought to compare the impact of sequential and contemporaneous revascularizations of portal vein and hepatic artery on biliary complications in patients undergoing liver transplantation.

METHODS

We reviewed 184 patients who underwent liver transplantation in our center, and categorized them into different groups based on the duration of time between the portal venous and hepatic arterial reperfusion: >10 minutes in the sequential portal and hepatic artery revascularization group (SPA; n = 56), and within 1 minute in the contemporaneous portal and hepatic artery revascularization group (CPA; n = 121).The other patients with an interval from 1-10 minutes (n = 7) were excluded. This study then compared the outcomes between the SPA and CPA groups.

RESULTS

Cold ischemic time (mean ± standard deviation) for the SPA and CPA groups were 561 ± 150 vs 577 ± 187 minutes, respectively (P = .53). The incidence of biliary complications for the SPA and CPA groups were 14/56 and 11/121, respectively (25% vs 9%; P = .005). By the Clavien-Dindo Classification of Surgical Complications, the biliary complications in SPA group tended to be more severe compared with the CPA group (grade I, 0% vs 0%; II, 14% vs 36%; IIIa, 71% vs 64%; IIIb, 7% vs 0%; IV, 7% vs 0%; P = .10). Among biliary complications, the incidence of nonanatomic strictures was greater in the SPA group (9% vs 2%; P = .03), whereas the difference was not significant for anastomotic strictures (P = .054). Except for a lower serum albumin level in the SPA group 1 day after liver transplantation (P < .001), there are no differences in post-transplant liver function or renal function at 1, 7, and 30 days after transplantation.

CONCLUSION

The CPA protocol can decrease the incidence of biliary complications substantially after liver transplantation and should replace the SPA protocol used by some centers in liver transplantation.

Protective effect of gadolinium chloride on early warm ischemia/reperfusion injury in rat bile duct during liver transplantation

Background

Activation of Kupffer cell (KC) is acknowledged as a key event in the initiation and perpetuation of bile duct warm ischemia/reperfusion injury. The inhibitory effect of gadolinium chloride (GdCl₃) on KC activation shows potential as a protective intervention in liver injury, but there is less research with regard to bile duct injury.

Methods

Sixty-five male Sprague-Dawley rats (200–250 g) were randomly divided into three experimental groups: a sham group (n = 15), a control group (n = 25), and a GdCl₃ group (n = 25). Specimen was collected at 0.5, 2, 6, 12 and 24 h after operation. Alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin (TBIL) of serum were measured. Tumor necrosis factor-α (TNF-α), Capase-3 activity and soluble Fas (sFas) were detected. The pathologic changes of bile duct were observed. Immunochemistry for bile duct Fas was performed. Apoptosis of bile duct cells was evaluated by the terminal UDP nick end labeling assay.

Results

GdCl₃ significantly decreased the levels of ALT, ALP and TBIL at 2, 6, 12, and 24 h, and increased serum sFas at 2, 6 and 12 h (P<0.05). TNF-α was lower in the GdCl₃ group than in the control group at 2, 6, 12 and 24 h (P<0.05). Preadministration of GdCl₃ significantly reduced the Caspase-3 activity and bile duct cell apoptosis at 2, 6, 12 and 24 h. After operation for 2, 6 and 12 h, the expression of Fas protein was lower in the GdCl₃ group than in the control group (P<0.05).

Conclusions

GdCl₃ plays an important role in suppressing bile duct cell apoptosis, including decreasing ALT, ALP, TBIL and TNF-α; suppressing Fas-FasL-Caspase signal transduction during transplantation.

Liver graft injury induced by ischemia and reperfusion secondary to retrograde reperfusion

AIM: To evaluate the influence of retrograde reperfusion on ischemia/reperfusion injury in a rat model of liver transplantation.

METHODS: Thirty-six male Sprague-Dawley rats undergoing orthoptic liver transplantation were divided into three groups (n = 12 for each group): group 1, antegrade reperfusion via the portal vein; group 2, antegrade reperfusion simultaneously via the portal vein and hepatic artery; group 3: retrograde reperfusion via the vena cava. Serum parameters were determined 1, 6 and 24 h after operation. Liver samples were taken for histological assessment. Cell apoptotic index was determined.

RESULTS: Rats of group 3 showed significantly lower serum level of aspartate aminotransferase compared to groups 1 and 2 (968.4 U/L ± 221.5 U/L vs 1 801.6 U/L ± 324.5 U/L, 2 564.1 U/L ± 410.3 U/L, P = 0.003, 0.000). Serum level of aspartate aminotransferase was significantly lower in group 1 than in group 2. The liver of rats of group 3 showed significantly less leukocytic infiltrates compared to groups 1 and group 2. The apoptotic index was lower in group 3 than in group 1 and 2.

CONCLUSION: Retrograde reperfusion leads to a lower level of ischemia/reperfusion injury than antegrade reperfusion in rats undergoing liver transplantation.