Prolonged preservation in University of Wisconsin solution associated with hepatic artery thrombosis after orthotopic liver transplantation

Superior Outcomes and Reduced Wait Times in Pediatric Recipients of Living Donor Liver Transplantation

Background

Living donor liver transplantation (LDLT) is increasingly used to bridge the gap between the current supply and demand imbalance for deceased donor organs to provide lifesaving liver transplantation.

Methods

Outcomes of 135 children who underwent LDLT were compared with 158 recipients of deceased donor liver transplantation (DDLT) at the largest pediatric liver transplant program in Canada.

Results

Recipients of LDLT were significantly younger than deceased donor recipients (P ≤ 0.001), less likely to require dialysis pretransplant (P < 0.002) and had shorter wait time duration when the primary indication was cholestatic liver disease (P = 0.003). The LDLT donors were either related genetically or emotionally (79%), or unrelated (21%) to the pediatric recipients. One-, 5-, and 10-year patient survival rates were significantly higher in LDLT (97%, 94%, and 94%) compared with DDLT (92%, 87%, and 80%; log-rank P = 0.02) recipients, as were graft survival rates (96%, 93%, and 93% for LDLT versus 89%, 81.4%, and 70%, respectively, for DDLT; log-rank P = 0.001). Medical and surgical complications were not statistically different between groups. Graft failure was higher in recipients of DDLT (odds ratio, 2.60; 95% confidence interval, 1.02, 6.58) than in the LDLT group after adjustment for clinical characteristics and propensity score.

Conclusions

Living donor liver transplantation provides superior outcomes for children and is an excellent and effective strategy to increase the chances of receiving a liver transplant.

Twenty Years of Experience in Pediatric Living Donor Liver Transplantation: Focus on Hepatic Artery Reconstruction, Complications, and Outcomes

BACKGROUND

Hepatic artery thrombosis (HAT) increases morbidity and mortality after liver transplantation (LT). The identification of risk factors for HAT may aid transplant teams in the development of strategies aimed at reducing HAT. This article describes the risk factors for HAT and outcomes after LT.

METHODS

This report describes a retrospective study (1995 to 2015) of primary pediatric living donor LT (LDLT). Pretransplant and technical variables were included in the study. Binary logistic regression was used for data analysis.

RESULTS

This study included 656 primary LDLT. The median age, body weight, and pediatric end-stage liver disease score at the time of transplant were 13 months, 8.4 kg and 15, respectively. Twenty-one (3.2%) patients developed HAT. Intraoperative HAT (odds ratio, 62.63; 95% confidence interval, 12.64-310.19; P < 0.001) and the use of liver grafts with a graft-to-recipient weight ratio less than 1.1% (odds ratio, 24.46; 95% confidence interval, 4.55-131.56; P < 0.001) retained statistical significance in the multivariate model. Patient and graft survivals were significantly worse in cases with HAT. The overtime trend analysis revealed a decrease in the incidence of HAT (P = 0.008) and an increase in the use of 2-arterial anastomosis (P < 0.001).

CONCLUSIONS

A graft-to-recipient weight ratio of 1.1% or less and intraoperative HAT were independently associated with HAT. Trend analysis further revealed a significant reduction in the incidence of HAT over time, as well as the increased use of 2 hepatic arteries for anastomosis during graft implantation. The double artery anastomosis may represent an extra protection to pediatric recipients undergoing LDLT.

Impact of Liver Graft Transport on Postoperative Results and Short-Term Liver Survival

BACKGROUND

The Andalusian community has a specific management model of liver transplantation with a common waiting list, forcing transportation of 45% of hepatic grafts. These trips within the community have been made exclusively via expressway since 2012, sometimes surpassing 400 km in distance. The objective of this study was to analyze the effect of graft transportation on our community regarding postoperative results, primary dysfunction, and short-term graft survival.

METHODS

This was a retrospective observational cohort study that included 110 patients recipients of liver transplants from 2009 to 2012. Group A (n = 53) were patients transplanted with grafts removed in Malaga, and group B (n = 57) were patients with transported grafts.

RESULTS

In group B, significant increments in total and cold ischemia time (TIT and CIT) were found. We found a significant higher increase, mostly in 2012, in TIT and CIT in the greater transportation distance subgroup (>150 km). In postoperative variables analysis, differences were found in the bilirubin levels the 1st postoperative day, alkaline phosphatase levels the 1st and 3rd days, and factor V in the 1st day in favor of the nontransported grafts. In the multivariable analysis transport and distance travelled in km presented a relationship with the 1st day bilirubin levels and the primary dysfunction of the graft.

CONCLUSIONS

Our results point to graft transportation having an influence on primary dysfunction and graft survival. This relationship can be multifaceted and influenced by currently unknown factors. This is a factor to consider regarding liver transplant management strategy decisions.

Intention-to-treat analysis of percutaneous endovascular treatment of hepatic artery stenosis after orthotopic liver transplantation

Hepatic artery stenosis (HAS) is a rare complication of orthotopic liver transplantation (LT). HAS could evolve into complete thrombosis and lead to graft loss, incurring significant morbidity and mortality. Even though endovascular management by percutaneous transluminal angioplasty ± stenting (PTA) is the primary treatment of HAS, its longterm impact on hepatic artery (HA) patency and graft survival remains unclear. This study aimed to evaluate longterm outcomes of PTA and to define the risk factors of treatment failure. From 2006 to 2012, 30 patients with critical HAS (>50% stenosis of HA) and treated by PTA were identified from 870 adult patients undergoing LT. Seventeen patients were diagnosed by post-LT screening, and 13 patients were symptomatic due to HAS. PTA was completed successfully in 27 (90%) patients with angioplasty plus stenting in 23 and angioplasty alone in 4. The immediate technical success rate was 90%. A major complication that was observed was arterial dissection (1 patient) which eventually necessitated retransplantation. Restenosis was observed in 10 (33%) patients. One-year, 3-year, and 5-year HA patency rates were 68%, 62.8%, and 62.8%, respectively. Overall patient survival was 93.3% at 3 years and 85.3% at 5 years. The 3-year and 5-year liver graft survival rates were 84.7% and 64.5%, respectively. No significant difference was observed in patient and graft survivals between asymptomatic and symptomatic patients after PTA. Similarly, no difference was observed between angioplasty alone and angioplasty plus stenting. In conclusion, endovascular therapy ensures a good 5-year graft survival (64.5%) and patient survival (85.3%) in patients with critical HAS by maintaining HA patency with a low risk of serious morbidity (3.3%). Liver Transplantation 22 923-933 2016 AASLD.

Polyethylene glycol rinse solution: An effective way to prevent ischemia-reperfusion injury

AIM: To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts.

METHODS: Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer’s lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1).

RESULTS: When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI.

CONCLUSION: Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI.

Endovascular treatment of hepatic artery stenosis after liver transplantation

BACKGROUND

Hepatic artery stenosis (HAS) after orthotopic liver transplantation is a significant risk factor for subsequent hepatic artery thrombosis (HAT). HAT is associated with a 30%-50% risk of liver failure culminating in retransplantation or death. Traditional treatment of hepatic artery complications has been surgical, with hepatic artery revision or retransplantation. Endovascular therapy of HAS, described primarily in the interventional radiology literature, may provide a less-invasive treatment option.

METHODS

This was a retrospective review of all endovascular interventions performed for HAS after orthotopic liver transplantation over a 31-month period (August 2009 to January 2012). Patients with duplex ultrasound imaging evidence of severe main HAS (peak systolic velocity of >400 cm/s, resistive index of <.5) underwent endovascular treatment with either primary stent placement or percutaneous transluminal angioplasty (PTA) alone. Patients were followed with serial ultrasound imaging to assess for treatment success and late restenosis. Reintervention was performed if significant restenosis occurred.

RESULTS

Thirty-five hepatic artery interventions were performed in 23 patients. Over the 31-month study period, 318 orthotopic liver transplantations were performed, yielding a 7.4% (23/318) rate of hepatic artery intervention. Primary technical success was achieved in 97% (34/35) of cases. Initial treatment was with PTA alone (n = 10) or primary stent placement (n = 13). The initial postintervention ultrasound images revealed improvements in hepatic artery peak systolic velocity (267 ± 118 [posttreatment] vs 489.9 ± 155 cm/s [pretreatment]; P < .0001) and main hepatic artery resistive index (0.61 ± 0.08 [posttreatment] vs 0.41 ± 0.07 [pretreatment]; P < .0001). At a mean follow-up of 8.2 ± 1.8 months (range, 0-29), there were 12 reinterventions in 10 patients for recurrent HAS. Thirty-one percent (n = 4/13) of patients undergoing initial stent placement required reintervention (at 236 ± 124 days of follow-up) compared with 60% (n = 6/10) of patients undergoing initial PTA (at 62.5 ± 44 days of follow-up). Primary patency rates (Kaplan-Meier) after primary stent placement were 92%, 85%, and 69% at 1, 3, and 6 months, respectively, compared with 70%, 60%, and 50% after PTA (P = .17). Primary-assisted patency for the entire cohort was 97% at 6 and 12 months. Major complications were one arterial rupture managed endovascularly and one artery dissection that precipitated HAT and required retransplantation. The overall rate of HAT in the entire cohort was 4.3% (1/23).

CONCLUSIONS

Endovascular treatment of HAS can be performed with high technical success, excellent primary-assisted patency, and acceptable morbidity. Initial use of a stent may improve primary patency when compared with PTA. The need for reintervention is common, placing particular importance on aggressive surveillance. Longer follow-up and a larger cohort are needed to confirm these encouraging early results.

Impact of very advanced donor age on hepatic artery thrombosis after liver transplantation

BACKGROUND

The impact of advanced donor age on hepatic artery thrombosis (HAT) after liver transplantation (LT) is controversial.

METHODS

We analyzed the incidence of and risk factors for HAT in LT with donors aged 70 years or older. Eighty patients were transplanted between 1998 and 2002 (group A) and 132 between 2003 and 2008 (group B).

RESULTS

In the more recent approach to hepatic artery (HA) reconstruction, the donor HA was systematically preferred to the Carrel patch/celiac trunk, the reconstruction of donor accessory right HA on the donor gastroduodenal artery significantly increased, and the use of interposition grafts was minimized. Group B showed higher Model for End-stage Liver Disease score, lower ischemia time, and lower use of the folding technique/mesenteric conduits. There were 10 cases of HAT (4.7%): 8 (10%) in group A and 2 (1.5%) in group B (P=0.007). Early HAT occurred in 7 (8.8%) patients in group A and in 2 (1.5%) in group B (P=0.02). Group A (P=0.01), anatomical variations of HA (P=0.005), and the use of interposition grafts (P=0.004) were all factors independently affecting HAT.

CONCLUSIONS

A low incidence of late HAT was observed in single-center LTs with very old donors. Early HAT decreased over time to largely acceptable rates because of more appropriate technical management.

Pharmacological strategies against cold ischemia reperfusion injury

IMPORTANCE OF THE FIELD

Good organ preservation is a determinant of graft outcome after revascularization. The necessity of increasing the quality of organ preservation, as well as of extending cold storage time, has made it necessary to consider the use of pharmacological additives.

AREAS COVERED IN THIS REVIEW

The complex physiopathology of cold-ischemia-reperfusion (I/R) injury--and in particular cell death, mitochondrial injury and endoplasmic reticulum stress--are reviewed. Basic principles of the formulation of the different preservation solutions are discussed.

WHAT THE READER WILL GAIN

Current strategies and new trends in static organ preservation using additives such as trimetazidine, polyethylene glycols, melatonin, trophic factors and endothelin antagonists in solution are presented and discussed. The benefits and mechanisms responsible for enhancing organ protection against I/R injury are also discussed. Graft preservation was substantially improved when additives were added to the preservation solutions.

TAKE HOME MESSAGE

Enrichment of preservation solutions by additives is clinically useful only for short periods. For longer periods of cold ischemia, the use of such additives becomes insufficient because graft function deteriorates as a result of ischemia. In such conditions, the preservation strategy should be changed by the use of machine perfusion in normothermic conditions.

Prevalence, treatment, and outcomes of the hepatic artery stenosis after liver transplantation

INTRODUCTION

Hepatic artery stenosis (HAS) after liver transplantation can lead to altered hepatic function and/or thrombosis, there by increasing morbidity and mortality. The prevalence of HAS in the literatures varies from 4% to 11%.

OBJECTIVE

We sought to describe the prevalence and treatment of hepatic artery stenosis.

METHODS

We performed a descriptive retrospective analysis of 253 liver transplantations from March 1998 to May 2007, including patients with suspected HAS owing to increased hepatic enzymes, altered Doppler ultrasound (us) and hepatic biopsy. The confirmation of HAS was achieved through areriography.

RESULTS

Nine patients were identified to have HAS, a 3.5% prevalence. Among the HAS patients, seven were male and two female. Their average age was 35.5 years (range, 65 to 53). The average time between the diagnosis and transplantation was 14.2 months (range, 9 to 68). The increase in hepatic enzymes among this group averaged: aspartate aminotransferase 131 U/L (range, 26 to 412) and alanine aminotransferase 192 U/L (range, 35 to 511). Doppler US showed alteration in the resistance level index. All patients underwent areriography; only one could not be treated owing to severe hepatic artery spasm, which also occurred during another attempt weeks after the first one. Among the eight patients, six were treated with stents and two with angioplastis. All treated patients displayed improvements in parameters. Four patients treated with stents required retreatment: two underwent angioplasty and two, a thrombolytic. One graft rethrombosed but evolved in compensated fashion with recanalization by collaterals. There has been no graft loss or mortality in this population. The average time of posttreatment follow-up was 31.28 (range, 9 to 68) months.

CONCLUSION

The prevalence of HAS in our unit was within that reported in the literature. Treatment with a stent or angioplasty proved to be efficient to control this complication, considering that hepatic function recovered and that there was neither graft nor patient loss.

Living-related versus deceased donor pediatric liver transplantation: a multivariate analysis of technical and immunological complications in 235 recipients

Timely access to a living donor (LD) reduced pretransplant mortality in pediatric liver transplantation (LT). We hypothesized that this strategy may provide better posttransplant outcome. Between July 1993 and April 2002, 235 children received a primary LT from a LD (n = 100) or a deceased donor (DD) (n = 135). Demographic, surgical and immunological variables were compared, and respective impact on posttransplant complications was studied using a multivariate analysis. Five-year patient survival rates were 92% and 85% for groups LD and DD, respectively (p = 0.181), the corresponding graft survival rates being 89% and 77% (p = 0.033). At multivariate analysis: (1) type of donor (DD) was correlated with higher rate of artery thrombosis (p < 0.012); (2) biliary complication rate at 5 years was 29% and 23% for groups LD and DD, respectively (p = 0.451); (3) lower acute rejection incidence could be correlated with type of donor (DD) (p = 0.001), and immunosuppressive therapy (tacrolimus) (p < 0.001). We conclude that (1) according to the multivariate analysis, LT with LD provided similar patient and graft outcome, when compared to DD; (2) a higher rate of artery thrombosis and a lower rate of rejection were observed in group DD; (3) this study confirms the efficacy of tacrolimus for immunoprophylaxis, whatever the type of organ donor is.

Risk factors contributing to hepatic artery thrombosis following living-donor liver transplantation

BACKGROUND/PURPOSE

This study was carried out to investigate the risk factors contributing to hepatic artery thrombosis in living-donor liver transplantation.

METHODS

Two hundred and twenty-two recipients (113 adults and 109 children) of living-donor liver transplantation were the subjects of this study. The diagnosis of hepatic artery thrombosis was made by color-Doppler ultrasonography and/or hepatic angiography. Parameters for this study were: (1) donor sex, age, and body weight; (2) recipient sex, age, body weight, liver disease, preoperative prothrombin time, and type of arterial reconstruction; and (3) previous liver transplantation.

RESULTS

Hepatic artery thrombosis occurred in 12 patients (5.4%) at 3 to 15 days posttransplant. Recipient female sex and metabolic disorder as the original disease were found to be significantly associated with hepatic artery thrombosis. The 5-year patient survival rate in recipients with hepatic artery thrombosis (58.3%) was significantly lower than that in recipients without this complication (84.4%).

CONCLUSIONS

Female sex and metabolic disease may be factors contributing to hepatic artery thrombosis after living-donor liver transplantation. More intensive anticoagulation therapy for this patient population might decrease the incidence of hepatic artery thrombosis and, thus, posttransplant recipient mortality.

Clinical outcomes from hepatic artery stenting in liver transplantation

Hepatic artery stenosis after liver transplantation may affect liver function and result in hepatic artery thrombosis. Surgical reconstruction has been the first choice for treatment. Interventional radiologic technique can be used, but there is no report on long-term outcome. The aim of this paper is to assess current outcome and complications of hepatic artery stenting. Twenty-six adult patients were stented for hepatic artery stenosis between 1998 and 2003. Nine patients had previous surgical reconstruction for hepatic artery stenosis. Seventeen patients suffered newly developed hepatic artery stenosis. Three patients were retransplanted. After stenting, the patients were followed by Doppler ultrasound at day 1, 1 month, and 6 months. Angiography was scheduled in 6 months. Four patients died within 2 months. The other 22 patients were followed for mean 31 +/- 14 months (8-71 months). One of 22 patients died from renal failure 2 years later. Twelve patients' hepatic arteries looked normal after stenting. Restenosis was seen in 8 patients (36%). Other complications were artery thrombosis (n = 1) and long segment stricture (n = 1). In 2 patients (25%) restenosis resulted in thrombosis. Six of the 8 patients who developed recurrent stenosis were successfully treated interventionally: restent (n = 5) and balloon dilation (n = 3). However, 3 patients (38%) restenosed. Kaplan-Meier complication-free survival was 54% at 1 year after stenting. In conclusion, hepatic artery stenting is a viable treatment for hepatic artery stenosis with reasonable results. Stenting is useful as adjuvant treatment after surgical revision.

Improved survival after live donor adult liver transplantation (LDALT) using right lobe grafts: program experience and lessons learned

We present our program experience with 85 live donor adult liver transplantation (LDALT) procedures using right lobe grafts with five simultaneous live donor kidney transplants using different donors performed over a 6-year period. After an "early" 2-year experience of 25 LDALT procedures, program improvements in donor and recipient selection, preoperative imaging, donor and recipient surgical technique and immunosuppressive management significantly reduced operative mortality (16% vs. 3.3%, p = 0.038) and improved patient and graft 1-year survival in recipients during our "later" experience with the next 60 cases (January 2001 and March 2005; patient survival: early 70.8% vs. later 92.7%, p = 0.028; graft survival: Early 64% vs. later 91.1%, p = 0.019, respectively). Overall patient and graft survival were 82% and 80%. There was a trend for less postoperative complications (major and minor) with program experience (early 88% vs. later 66.7%; p = 0.054) but overall morbidity remained at 73.8%. Biliary complications (cholangitis, disruption, leak or stricture) were not influenced by program experience (early 32% vs. later 38%). Liver volume adjusted to 100% of standard liver volume (SLV) within 1 month post-transplant. Despite a high rate of morbidity after LDALT, excellent patient and graft survival can be achieved with program experience.

Cadaveric full-size liver transplantation and the graft alternatives in adults: a comparative study from a single centre

BACKGROUND/AIMS

This study aims to compare the results of living donor (LDLT), cadaveric split (SLT) and domino (DO) liver transplantation which are currently available alternatives to the conventional cadaveric full-size liver transplantation (CAD).

METHODS

Immunologic, vascular and biliary complications (BC) were evaluated in 38 LDLT, 20 SLT, 17 DO and 38 CAD recipients.

RESULTS

The incidence of acute rejection (AR) was similar between groups, and between blood-related and blood-unrelated patients. AR was more severe in the SLT group according to the Banff scores (P=0.03, P<0.001, P<0.001). The evolution of AR was similar between the groups, in terms of development of chronic rejection. No venous complications occurred in the overall population. The rate of arterial thrombosis (10.5, 10, 0 and 3%, respectively) was statistically similar between groups. The rate of BC (26, 40, 12, and 8%, respectively) was higher in the partial grafts than in the whole grafts (P=0.006), but was not significantly different within each group. There was an association between the severity of preservation injury and occurrence of AR (P=0.01) and arterial thrombosis (P=0.016), but not BC. One- and 2-year graft and patient survival rates were similar between groups.

CONCLUSIONS

None of the graft types seemed to confer immunological advantage. BC remained problematic in the partial grafts, independently from ischemia time.

Intrahepatic biliary strictures without hepatic artery thrombosis after liver transplantation: an analysis of 1,113 liver transplantations at a single center

BACKGROUND

Intrahepatic biliary strictures (IHBS) without hepatic artery thrombosis (HAT) is a serious complication and known to increase the risk of graft failure after liver transplantation. This manuscript describes the incidence, risk factors, clinical pictures, management, and outcomes.

METHODS

Between 1994 and 2002, 1,113 liver transplantations were performed in 974 adult patients. Data was retrospectively analyzed in terms of incidence, risk factors, clinical pictures (type of strictures), management (radiologic, surgical management), and outcomes.

RESULTS

Sixteen (1.4%) grafts had IHBS without HAT. Specific risk factors were not identified from donors or recipients. However, ischemic factors from the donors were suspected from non-heart-beating donors (n=1) and cardiac-arrest donors (n=2). Three types of IHBS were identified: (1) diffuse type (n=7), (2) bilateral proximal type (n=7), and (3) unilateral type (n=2). Overall success rate of radiologic interventions was 31.3% (5/16). Of the 11 patients who did not improve, 6 died: diffuse type (3/7, 42.9%), bilateral type (3/7, 42.9%), and unilateral (0/2, 0%). Three patients had retransplantation, and two patients are waiting retransplantation. The majority of the IHBS were diffuse or bilateral (14/16, 87.5%), and rate of the graft failure was high (10/14, 71.4 %). Overall graft survival of IHBS was lower than that without IHBS (P=0.025).

CONCLUSIONS

The majority of the IHBS without HAT were of a diffuse or bilateral proximal type. Patients with diffuse or bilateral proximal type have a low success rate from radiologic intervention and may benefit from early retransplantation.

The role of complex hepatic artery reconstruction in orthotopic liver transplantation

The goal of this study was to analyze the influence of multiple anastomosis on outcome in orthotopic liver transplantation (OLT) and its implications for split-liver and living related liver transplantation programs. In a retrospective study, 683 first OLTs in adults were analyzed. Complex hepatic artery reconstruction was defined as revascularization of the graft requiring additional anastomosis between donor hepatic arteries. OLT was performed in a standard manner. All patients had daily ultrasound examination. In this series we found 72 grafts (10.5%) with anatomic arterial variations that required complex hepatic artery reconstruction. There was no difference in primary organ function and demographic data compared with patients with simple arterial reconstruction. However, hepatic artery thrombosis (HAT) occurred in 9.7% of patients (7 of 72) with complex reconstruction in contrast to 2.0% in the control group (12 of 638; P <.001). Statistical analysis identified multiple anastomoses (P <.002) and primary nonfunction (P <.02) as significant risk factors for HAT. Three patients underwent successful thrombectomy for HAT, all others had to undergo retransplantation. Although in the group with complex arterial reconstruction increased graft loss caused by HAT was found early postoperatively, the overall 5-year patient and graft survival was not different for both groups. Although complex reconstruction is a risk factor for HAT, early diagnosis of HAT by daily ultrasound and early repeat OLT can provide similar 5-year survival as for patients with simple reconstruction. We conclude that complex hepatic artery reconstruction challenges conventional OLT as well as split-liver and living related liver transplantation, but does not necessarily affect its long-term outcome.

Hyperaggregating effect of hydroxyethyl starch components and University of Wisconsin solution on human red blood cells: a risk of impaired graft perfusion in organ procurement?

BACKGROUND

The standard preservation solution used during organ procurement and preservation of most organs is the University of Wisconsin (UW) solution. Despite its superiority over other cold storage solutions, the inclusion of hydroxyethyl starch (HES) as one of the components of the UW solution has been both advocated and denied. This study determined whether HES had any effect on red blood cell (RBC) aggregability and correlated aggregation parameters with HES molecular weight.

METHODS

Human RBC aggregability and deformability were investigated in vitro, at 4 degrees C, with a laser-assisted optical rotation cell analyzer. The study of RBC aggregation in a binary HES-HES system gave an indication about the nature of HES-RBCs interactions. Bright field microscopy and atomic force microscopy were used to morphologically characterize the aggregates size and form.

RESULTS

High molecular weight HES and UW solution had a potent hyperaggregating effect; low molecular weight HES had a hypoaggregating effect on RBC. RBC aggregates were of large size and their resistance to dissociation by flow-induced shear stress was high.

CONCLUSION

The authors' in vitro experiments conclusively showed that the physiologic function of RBCs to form aggregates is significantly affected in the presence of HES. The use of high molecular weight HES in UW solution accounts for extended and accelerated aggregation of erythrocytes that may result in stasis of blood and incomplete washout of donor organs before transplantation.

Worth continuing doing ex situ liver graft splitting? A single-center analysis

Grafts for split liver transplantation can be prepared in situ during the retrieval operation, or ex situ on the back table. The in situ technique has theoretical advantages because it minimizes the cold ischemic time and allows excellent hemostasis at the cut surface. However, in situ liver division prolongs the retrieval procedure, may precipitate hemodynamic instability in the donor, and may cause logistical difficulties for some centers. This report is a single-center analysis comparing results of ex situ liver division (group I: 1992-97; and group II: 1998-2001) before and after a new protocol for liver graft division was introduced in our center. Eighty-nine split liver transplants (SLT) were reviewed retrospectively. Vascular complications were less common in group II (3.3% vs. 20%; p = 0.04), and 1-year graft survival increased from 59% to 78% (p = 0.03). Since 1998, 1-year graft survival of SLT has been similar to that of conventional liver graft transplantation in our center (78% and 74%, respectively). In conclusion, good results can be achieved from splitting livers ex situ and this procedure should be considered when the in situ technique is not feasible.

Is presensitization relevant to liver transplantation outcome?

The impact of anti-HLA antibodies and crossmatch (CM) on liver transplantation (LT) outcome is still controversial. In this retrospective study we analyzed LT outcome according to pretransplant pre-formed anti-HLA antibodies and CM status. Serum anti-HLA antibodies were screened by ELISA assay, utilizing One Lambda antigen tray-mixed (LAT-M). CMs were performed by the complement dependent cytotoxicity test using Dithiotreitol treated sera. Anti-HLA antibodies were studied in 80 recipients; 56/80 had positive LAT-M tests (PLAT-M), whereas the remaining 24 recipients tested negative for both classes I and II (NLAT-M). Rejection episodes were more frequent in PLAT-M compared with NLAT-M group in post-LT intervals of <1 week (p = 0.05), 1 week-3 months (p = 0.035), and 3-12 months (p = 0.076). Graft and patient survival rates were better, albeit not significantly, in the NLAT-M compared with PLAT-M recipients. CM status was investigated in 62/80 recipients, 18/62 recipients had positive CM (PCM), and 44 had negative CM (NCM). Five of 18 PCM recipients (28%) experienced early graft loss compared with 1/44 (2%) with NCM (p = 0.006). Rejection episodes were more frequent within first 3 months post-LT in PCM recipients compared with NCM (p = 0.015). One-year graft survival rate was better in NCM, compared with PCM recipients (graft loss of 2/44 vs 5/18). NCM PLAT-M had a higher incidence of rejection episodes compared with the NCM NLAT-M group (p = 0.031). The presence of anti-HLA antibodies suggests a deleterious effect on LT outcome, and was associated with an increased incidence of early graft loss and rejection episodes.

Cigarette smoking is associated with an increased incidence of vascular complications after liver transplantation

Hepatic artery thrombosis (HAT) and other vascular complications are significant causes of morbidity after liver transplantation. Although cigarette smoking increases the risk of vascular complications after renal transplantation, its impact after liver transplantation remains unknown. Between May 1995 and April 2001, 288 liver transplantations were performed in 263 patients. Vascular complications developed in 39 patients (13.5%) (arterial complications, 28 patients [9.7%]; venous complications, 11 patients [3.8%]). Patient demographics, comorbid illnesses, and risk factors were analyzed using the Mann-Whitney U test, Chi-squared test, and Fisher's exact test. In patients with a history of cigarette smoking, incidence of vascular complications was higher than in those without history of cigarette smoking (17.8% v 8%, P =.02). Having quit cigarette smoking 2 years before liver transplantation reduced the incidence of vascular complications by 58.6% (24.4% v 11.8%, P =.04). The incidence of arterial complications was also higher in patients with a history of cigarette smoking compared with those without such history (13.5% v 4.8%, P =.015). Cigarette smoking cessation for 2 years also reduced the risk of arterial complications by 77.6% (21.8% v 5.9%, P =.005). However, the incidence of venous complications was not associated with cigarette smoking. Furthermore, there was no significant association between development of vascular complications and all other characteristics studied. Cigarette smoking is associated with a higher risk for developing vascular complications, especially arterial complications after liver transplantation. Cigarette smoking cessation at least 2 years before liver transplantation can significantly reduce the risk for vascular complications. Cigarette smoking cessation should be an essential requirement for liver transplantation candidates to decrease the morbidity arising from vascular complication after liver transplantation.

Postreperfusion biopsies are useful in predicting complications after liver transplantation

Biliary complications after orthotopic liver transplantation (OLT) may occur because of preservation injury (PI). In this study, we examine findings on routine reperfusion biopsy specimens in relation to the occurrence of biliary complications and graft outcome. From 1997 to 2000, a total of 193 OLTs were performed in our center. Postreperfusion biopsy specimens were analyzed and histological lesions were graded. For analysis, grafts were grouped into 2 categories: the presence or absence of PI (severe to moderate lesions versus mild or no lesions). Histological evidence of PI was present in 17% of the biopsy specimens. The incidence of grafts with PI and ischemia time longer than 12 hours was 38% compared with 14% in PI and short ischemia time (P =.02). Biliary complications were also more frequent in the PI group (28% v 14%; P =.03). Study of risk factors by means of logistic regression analysis confirmed that the PI group had a greater risk for biliary complications (relative risk, 2.8; 95% confidence interval, 1 to 7.4; P =.03). Moreover, moderate macrovesicular steatosis was found in 6% of the grafts, resulting in a 40% graft loss rate. We found that an increased presence of neutrophilic infiltrates in the postreperfusion biopsy specimen, indicating PI, was related to an increased incidence of biliary complications. Moreover, moderate macrovesicular steatosis was associated with increased graft loss. Therefore, postreperfusion biopsies are useful in anticipating post-OLT complications.

Split-liver transplantation for two adult recipients: feasibility and long-term outcomes

OBJECTIVE

To identify the outcomes and risks of split-liver transplantation (SLT) for two adult recipients to determine the feasibility of more widespread use of this procedure to increase the graft pool for adults.

SUMMARY BACKGROUND DATA

The shortage of cadaver liver grafts for adults is increasing. Using livers from donors defined as optimal, the authors have been developing techniques for SLT for two adult recipients at their center.

METHODS

From July 1993 to December 1999, 34 adults have undergone SLT with grafts from optimal donors prepared by ex situ split (n = 30) or in situ split (n = 4), and 88 adults received optimal whole-liver grafts that were not split. Four split-grafts were transplanted at other centers. The outcomes of transplantation with right and left split-liver grafts were compared with those of whole-liver transplants. The main end points were patient and graft survival at 1 and 2 years and the incidence and types of complications.

RESULTS

For whole-liver, right and left split-liver grafts, respectively, patient survival rates were 88%, 74%, and 88% at 1 year and 85%, 74%, and 64% at 2 years. Graft survival rates were 88%, 74%, and 75% at 1 year and 85%, 74%, and 43% at 2 years. Patient survival was adversely affected by graft steatosis and recipients inpatient status before transplantation. Graft survival was adversely affected by steatosis and a graft-to-recipient body weight ratio of less than 1%. Primary nonfunction occurred in three left split-liver grafts. The rates of arterial (6%) and biliary (22%) complications were similar to published data from conventional transplantation for an adult and a child. SLT for two adults increased the number of recipients by 62% compared with whole-liver transplantation and was logistically possible in 16 of the 104 (15%) optimal cadaver donors.

CONCLUSIONS

Split-liver transplantation for two adults is technically feasible. Outcomes and complication rates can be improved by rigid selection criteria for donors and recipients, particularly for the smaller left graft, and possibly also by in situ splitting in cadaver donors. Wider use will require changes in the procedures for graft allocation and coordination between centers experienced in the techniques.

Hepatic artery thrombosis after orthotopic liver transplantation: a review of nonsurgical causes

Hepatic artery thrombosis (HAT) is one of the principal causes of morbidity and graft loss following liver transplantation. There are several risk factors for the development of HAT; technical aspects of the arterial anastomosis are important particularly for early thrombosis, but the improvement of surgical technique has lessened this problem. Apart from technical causes, other risk factors include a variety of conditions such as low donor/recipient age ratio, immunologic factors, clotting abnormalities, tobacco use, and infections. In particular, cytomegalovirus (CMV) infection of endothelial cells has been recently suggested as an infective cause of HAT, as it is known to be followed by a rapid procoagulant response. Thus, latent CMV in an allograft may become activated and promote or contribute to vascular thrombosis. This review evaluates these aspects, focusing on data relating CMV infection or viremia to HAT following liver transplantation.

Safety and risk of using pediatric donor livers in adult liver transplantation

Pediatric donor (PD) livers have been allocated to adult transplant recipients in certain situations despite size discrepancies. We compared data on adults (age > or = 19 years) who underwent primary liver transplantation using livers from either PDs (age < 13 years; n = 70) or adult donors (ADs; age > or = 19 years; n = 1,051). We also investigated the risk factors and effect of prolonged cholestasis on survival in the PD group. In an attempt to determine the minimal graft volume requirement, we divided the PD group into 2 subgroups based on the ratio of donor liver weight (DLW) to estimated recipient liver weight (ERLW) at 2 different cutoff values: less than 0.4 (n = 5) versus 0.4 or greater (n = 56) and less than 0.5 (n = 21) versus 0.5 or greater (n = 40). The incidence of hepatic artery thrombosis (HAT) was significantly greater in the PD group (12.9%) compared with the AD group (3.8%; P =.0003). Multivariate analysis showed that preoperative prothrombin time of 16 seconds or greater (relative risk, 3.206; P =.0115) and absence of FK506 use as a primary immunosuppressant (relative risk, 4.477; P =.0078) were independent risk factors affecting 1-year graft survival in the PD group. In the PD group, transplant recipients who developed cholestasis (total bilirubin level > or = 5 mg/dL on postoperative day 7) had longer warm (WITs) and cold ischemic times (CITs). Transplant recipients with a DLW/ERLW less than 0.4 had a trend toward a greater incidence of HAT (40%; P <.06), septicemia (60%), and decreased 1- and 5-year graft survival rates (40% and 20%; P =.08 and.07 v DLW/ERLW of 0.4 or greater, respectively). In conclusion, the use of PD livers for adult recipients was associated with a greater risk for developing HAT. The outcome of small-for-size grafts is more likely to be adversely affected by longer WITs and CITs. The safe limit of graft volume appeared to be a DLW/ERLW of 0. 4 or greater.

Increased late hepatic artery thrombosis rate and decreased graft survival after liver transplants with zero cross-reactive group mismatches

The use of broad-specificity cross-reactive groups (CREGs) at the A and B HLA loci has been proposed as a means to improve both access and outcome for renal transplantation but has not yet been studied for liver transplantation. We retrospectively analyzed our results for all adult liver transplantations performed at our center between 1989 and 1996 for which HLA typing and complete 3-year follow-up data were available. Two hundred eight transplantations were studied, with a mean follow-up of 66 +/- 2 months (range, 36 to 110 months); A and B loci were converted to CREGs by the method of Rodey. Thirteen percent of the patients with 0 CREG mismatches had hepatic artery thrombosis versus 2% for those with 1 or more mismatches (odds ratio, 6.7; 95% confidence interval, 2.6 to 17.3 by univariate analysis; odds ratio, 3.5; 95% confidence interval, 1.1 to 11.7 by logistic regression analysis). These events occurred significantly later in the 0-CREG mismatch group (21 +/- 7 v 4 +/- 2 months posttransplantation; P =.04 by Student's t-test). Graft survival rates were significantly lower for patients with 0 CREG mismatches (56% v 68% at end of study; P =.05 by Cox-Mantel test). The number of CREG mismatches had no effect on the frequency of rejection, steroid-resistant rejection, or infectious complications, including cytomegalovirus. Neither total nor individual A, B, or DR HLA matching had an effect on outcome. There appears to be little evidence that intentional CREG matching would improve outcomes for liver transplantation and, under some circumstances, could be deleterious.

Right lobe living donor liver transplantation: a review

The continuing shortage of organs for adult transplant recipients has generated enthusiasm for adult-to-adult living donor liver transplantation (LDLT). The major concern has been the ability to resect a graft of adequate size without subjecting the donor to undue risk. The right hepatic lobe is generally large enough for adult recipients, but because of the real and perceived risks of right lobe (RL) resection, surgeons have been hesitant to offer this option to their patients. The first series of RL resections that included a significant number of patients was reported in 1999, and the results were encouraging. Only minor complications occurred in donors, and the recipients fared quite well. Enthusiasm for these donor resections is growing, and more centers are beginning to perform them. There is a good deal of global experience with pediatric LDLT but little with adults, and there are unique considerations in this population. This review examines donor selection criteria for adult recipients, highlights technical points critical for good outcome, and examines the early results and complications in both donors and recipients. If the preliminary results continue to be reproduced, RL LDLT could have significant impact on the worsening organ shortage.

Pediatric liver transplantation with cadaveric or living related donors: comparative results in 90 elective recipients of primary grafts

STUDY DESIGN

Between July 1993 and March 1997, 110 children were listed for primary elective liver transplantation with cadaveric (Cad: n = 68) or living-related (LR: n = 42) donors. Pregraft mortality, post-transplant survival, and surgical and immunologic complications were retrospectively compared in both groups.

RESULTS

The pregraft mortality rate was 10 (15%) of 68 versus 1 (2%) of 42 in the Cad and LR groups, respectively (P =.049). Postliver transplantation 1-year patient and graft survival rates were 87% and 75% in the Cad group (n = 49) versus 92% and 90% in the LR group (n = 41), respectively (NS). The incidence of post-transplant complications was as follows: hepatic artery thrombosis (Cad: 16%; LR: 0%, P =.020), portal vein thrombosis (Cad: 8%; LR: 2%, NS), and biliary complications (Cad: 14%; LR: 34%, P =.044). The overall incidence of acute rejection was similar in both groups; however, a lower incidence of acute rejection occurred in LR graft recipients treated with tacrolimus.

CONCLUSIONS

The introduction of an LR donor liver transplantation program allowed a significant decrease in the pretransplant mortality rate, with a consequent overall improvement in patient survival compared with the Cad series. The incidence of biliary complications was higher in the LR series, whereas better human leukocyte antigen matching in this subgroup did not result in a lower rejection incidence.

Hepatic artery thrombosis in pediatric liver transplantation: graft salvage after thrombectomy

Hepatic artery thrombosis (HAT) is a devastating complication that may occur after orthotopic liver transplantation (OLT). A higher incidence has been reported in children. Salvage of the graft by thrombectomy has been suggested as an alternative to re-transplantation. In this study we report the outcome of three children who underwent thrombectomy for HAT. Between January 1992 and June 1998, 14 children (< 17 yrs of age) underwent liver transplantation. Three developed HAT (one a whole-liver graft recipient, age 17; two living-related graft recipients, ages 4 and 4.5 yr). In the first patient, thrombosis of the hepatic artery was associated with scattered areas of parenchymal necrosis on computed tomography. In the two living-related patients, HAT was found incidentally during re-exploration for bleeding (day 2 and day 10). Thrombectomy was performed in all three patients. At 18-24 months after thrombectomy, all three children had normal graft function. In the first patient, complete regeneration of the liver has been documented by computed tomography and a late asymptomatic recurrent thrombosis is suggested by absence of arterial flow on Doppler examination. The hepatic artery is patent in the two living-related recipients. One of these living-related recipients developed ischemic bile duct stricture and underwent successful percutaneous balloon dilatation. We conclude that long-term normal graft function can be achieved by thrombectomy in pediatric liver recipients with HAT, even in the presence of limited parenchymal damage.

Cytomegalovirus and its association with hepatic artery thrombosis after liver transplantation

BACKGROUND

Hepatic artery thrombosis (HAT) is a cause of morbidity and graft loss in approximately 7% of patients after an orthotopic liver transplantation (OLT). Although technical problems are often thought to be the cause of HAT, in general the etiology remains unclear. Because cytomegalovirus (CMV) can infect endothelial cells in vitro and lead to a rapid procoagulant response, it can be hypothesized that, in the absence of CMV antibodies, latent CMV in an allograft may become activated and promote or contribute to vascular thrombosis. Therefore, the purpose of this study was to examine the relationship between CMV serology of the donor and recipient with the development of HAT after OLT.

METHODS

Between July 1988 and November 1995 (University of Wisconsin era), 490 OLTs were performed in 413 patients. Subsequently, four patients were excluded in whom the CMV serology results of the donor were not available. Sixteen of the 409 patients developed HAT within 30 days after liver transplantation. The control group consisted of the other 393 patients.

RESULTS

The incidence of HAT was 12.5% in 64 CMV D+R- patients and 0% in 52 CMV D-R- patients. However, in the other combinations (D+R+ and D-R+), the incidence was only 2.8% (P = 0.005). Eight of the 16 patients with HAT belonged to the CMV D+R- group.

CONCLUSIONS

We conclude that CMV-seronegative patients receiving a seropositive allograft may be at risk for early HAT. Seropositivity of the donor alone and of the recipient alone was not significantly related to the incidence of HAT. Prophylactic treatment with ganciclovir and/or anticoagulation should be evaluated to prevent this complication.

Biphasic spiral computed tomography versus digital subtraction angiography for evaluation of arterial thrombosis after orthotopic liver transplantation

RATIONALE AND OBJECTIVES

The authors characterize the spiral computed tomographic (CT) findings in patients with hepatic arterial thrombosis after orthotopic liver transplantation (OLT).

METHODS

In nine with and 15 patients without hepatic artery thrombosis (HAT) after OLT, unenhanced and contrast-enhanced biphasic spiral CT was performed during arterial and venous phases, and evaluated by consensus of two blinded readers. Evaluation included signs of parenchymal and vascular changes in the liver. Findings subsequently were correlated with those of digital subtraction angiography (DSA).

RESULTS

Among all patients, eight had complete occlusion of the proximal hepatic artery and one patient had partial thrombosis, as revealed by conventional DSA. Characteristic CT findings of HAT included irregularly shaped confluent hypoattenuating liver areas (n = 8), seen both before and after administration of contrast material. Necrotic lesions and changes consistent with ischemic type of biliary lesion were documented in six patients. Biphasic CT allowed detection of HAT in eight patients. Because of inadequate contrast enhancement during the arterial phase, thrombosed intrahepatic arteries were not adequately diagnosed in one patient. Overall CT sensitivity to detect HAT was 89%, specificity was 100%.

CONCLUSIONS

Characteristic biphasic spiral CT findings in hepatic artery thrombosis contribute to early detection of arterial thrombosis after OLT and are helpful for planning more invasive diagnostic approaches.

Efficacy of intraportal infusion of prostaglandin E1 to improve the hepatic blood flow and graft viability in porcine liver transplantation

BACKGROUND

Prostaglandin E1 (PGE1) has been reported to have a protective effect in experimental and clinical models of liver damage. The aim of this study was to elucidate the effects of the intraportal infusion of PGE1 on hepatic blood flow and graft viability after orthotopic liver transplantation in pigs.

METHODS

First, the hepatic arterial flow (HAF), portal venous flow (PVF), and liver tissue blood flow (LTBF) were measured during the continuous intravenous or intraportal infusion of PGE1. Second, two groups of pigs underwent orthotopic liver transplantation: group A, untreated controls; and group B, animals that received intraportal PGE1 for 2 hr after vascular reconstruction of the allograft. Changes in HAF, PVF, LTBF, and hepatic function were measured.

RESULTS

The intraportal infusion of PGE1 significantly increased HAF and had no effect on blood pressure, PVF, or LTBF. In group B, HAF and LTBF increased significantly with time. In group A, HAF remained unchanged and a decrease in LTBF was observed. Group B exhibited a higher arterial ketone body ratio and a greater bile flow compared with group A. A significant elevation in serum glutamic oxaloacetic transaminase concentration was observed in group A, but not in group B.

CONCLUSIONS

This study demonstrates that the intraportal infusion of PGE1 improves hepatic allograft blood flow, predominantly through an effect on HAF, and may improve graft viability after orthotopic liver transplantation.

A positive crossmatch in liver transplantation--no effect or inappropriate analysis? A prospective study

BACKGROUND

Controversy over the relationship of preformed lymphocytotoxic antibodies and liver graft outcome remains. Because graft loss associated with preformed lymphocytotoxic antibodies probably occurs early after transplant, analysis of long-term survival is of questionable value. We therefore prospectively analyzed the effect on short- and long-term graft survival of the presence of lymphocytotoxic alloantibody in 207 primary adult liver allograft recipients.

METHODS

Pretransplant serum was tested for donor-specific lymphocytotoxic antibodies and panel-reactive antibodies (PRA) using donor splenic lymphocytes and lymphocytes obtained for routine tissue typing.

RESULTS

A positive crossmatch was detected in 24 recipients (11.5%): T-cell positive in 11 recipients and B-cell positive in 13 recipients. PRA were detected in 68 of 179 recipients tested (37.4%). High T-cell PRA (>55%) was detected in 17 recipients, and high B-cell PRA was detected in 20 recipients. Low PRA (<15%) against T cells was detected in 19 recipients and against B cells in 24 recipients. Graft failures occurred in 5 of 24 (21%) crossmatch-positive recipients and in 7 of 172 (4%) crossmatch-negative recipients. Graft survival was significantly lower in crossmatch-positive recipients at 1 month after transplant (chi-square=10.3, P=0.00133) but not at 3 months or 1 year. Causes of early graft loss were associated with immunological mechanisms, whereas later losses were due to nonimmunological mechanisms.

CONCLUSIONS

Early graft loss may be increased in those recipients who are crossmatch positive. However, the logistical problems and consequences associated with allocation probably outweigh the benefits of prospective crossmatching.

The impact of microsurgical hepatic arterial reconstruction on the outcome of liver transplantation for congenital biliary atresia

BACKGROUND

Hepatic artery thrombosis (HAT) after liver transplantation for biliary atresia (BA) is a serious complication that most often leads to retransplantation (re-OLT). The purpose of the present study was: (1) to identify risk factors associated with HAT and (2) to analyze the impact of recently introduced microsurgical hepatic arterial reconstruction (MHR) on the incidence of HAT, subsequent need for re-OLT, and patient survival.

METHODS

A retrospective review of 194 patients transplanted for BA was performed. One hundred and sixty-six patients (group 1) underwent conventional arterial reconstruction and 28 (group 2) had MHR.

RESULTS

Actuarial survival for patients with HAT was significantly worse than for patients without HAT at 1, 2, and 5 years (71%, 61%, and 57% versus 85%, 85%, and 85%, P = 0.0007). Stepwise logistic regression analysis revealed that the risk of HAT correlated best with the type of arterial reconstruction (P = 0.007) followed by pretransplant bilirubin concentration (P = 0.04) and the number of acute rejection episodes (P = 0.03). In group 1, 32 patients developed HAT (19%), and of these, 18 underwent re-OLT for HAT. No patient in group 2 developed HAT (P = 0.006 versus group 1). One-year actuarial patient survival was 81% in group 1 and 100% in group 2 (P = 0.02).

CONCLUSIONS

In OLT for BA, (1) the predominant risk factor for HAT is the technique of arterial reconstruction, and (2) MHR markedly reduces the incidence of HAT and the need for re-OLT while improving patient survival.

Split-liver transplantation. The Paul Brousse policy

OBJECTIVE

The authors objective is to report their recent experience with split-liver transplantation, focusing on the results and the impact on organ shortage.

SUMMARY BACKGROUND DATA

There is an insufficient number of organs for liver transplantation. Split-liver transplantation is a method to increase the number of grafts, but the procedure is slow to gain wide acceptance because of its complexity and the poor results reported in previous series.

METHODS

During the year 1995, the authors split 20 of 83 transplantable livers allocated to the authors' center, generating 40 grafts: 23 were transplanted locally and 17 were given to partner centers. During the same period, the authors accepted four split-liver grafts proposed to them by other centers. Overall, 27 split-liver transplantations were done in the authors' unit, accounting for 30% of the 90 transplants performed in 1995.

RESULTS

One-year patient and graft survival rates for split-liver transplantation were 79.4% and 78.5%, respectively. Arterial and biliary complications rates were 15% and 22%, respectively, with none leading to graft loss. Primary nonfunction occurred in one case (4%). By splitting 24 of 87 transplantable livers (4 of which were in partner units), a total of 111 transplantations were performed, increasing graft availability by 28%.

CONCLUSIONS

Split-liver transplantation is achieving graft and patient survival rates similar to that of whole liver transplantation despite a higher incidence of complications, which could become less frequent as experience is gained with this procedure. A wider acceptance of split-liver transplantation could markedly increase the supply of liver grafts.

Orthotopic liver transplantation for congenital biliary atresia. An 11-year, single-center experience

OBJECTIVE

The authors analyze a single center's 11-year experience with 190 orthotopic liver transplants for congenital biliary atresia.

SUMMARY BACKGROUND DATA

Hepatic portoenterostomy generally is the initial treatment for children with congenital biliary atresia. Despite multiple modifications of the hepatic portoenterostomy, two thirds of treated patients still develop recurrent cholestasis, portal hypertension, cholangitis, and cirrhosis. Therefore, the only hope of long-term survival in the majority of children with congenital biliary atresia is definitive correction with orthotopic liver transplantation.

METHODS

The medical records of 190 consecutive patients undergoing orthotopic liver transplantation for congenital biliary atresia from July 1, 1984 to February 29, 1996 were reviewed. Results were analyzed via Cox multivariate regression analysis to determine the statistical strength of independent associations between pretransplant covariates and patient and graft survival. Actuarial patient and graft survival was determined at 1, 2, and 5 years. The type and incidence of post-transplant complications were determined, as was the quality of long-term graft function. The median follow-up period was 3.21 years.

RESULTS

The liver grafts were comprised on 155 whole-organ, 24 reduced-size, and 11 living donor organs. Median pretransplant values for recipient age, weight, and total bilirubin were 1.4 years, 12.3 kg, and 13.8 mg/dL, respectively. One hundred sixty-four patients (86%) had undergone prior hepatic portoenterostomy. Eighty-seven patients (46%) were United Network for Organ Sharing (UNOS) status 1 or 2 at the time of liver transplantation. The majority (15/24, 62%) of reduced-size graft recipients were UNOS status I at the time of transplantation. One hundred fifty-nine patients (84%) received a single graft, whereas 31 patients required 37 retransplants. The 1, 2, and 5 year actuarial patient survival rates were 83%, 80% and 78% respectively, whereas graft survival rates were 81%, 77%, and 76%, respectively. Cox multivariate regression analysis demonstrated that pretransplant total bilirubin, UNOS status, and graft type significantly predicted patient survival, whereas recipient age, weight, and previous hepatic portoenterostomy did not. Current median follow-up values for total bilirubin and aspartate aminotransferase levels in the 154 surviving patients were 0.5 mg/dL and 34 international units/L, respectively.

CONCLUSION

Long-term patient survival after orthotopic liver transplantation for congenital biliary atresia is excellent and is independent of recipient age, weight, or previous hepatic portoenterostomy. Optimal results are obtained in this patient population when liver transplantation is performed before marked hyperbilirubinemia, and when possible, using a living-donor graft.

Rapid en bloc technique for pancreas-liver procurement. Improved early liver function

It is our experience that warm dissection in the porta hepatis as well as extensive organ mobilization during combined pancreas-liver procurements may cause posttransplant dysfunction of the liver. To avoid this, we recently utilized a rapid en bloc procurement technique with minimal warm dissection and division of the liver and pancreas ex vivo. Fifteen procurements were performed using this rapid en bloc technique; seventeen procurements involved extensive dissection followed by sequential in situ procurement of the liver and pancreas grafts. The control group consisted of 15 age-matched patients who received livers when no pancreas was harvested. Dissection time was 157 +/- 13 min (mean +/- SEM) in the in situ group, 78 +/- 3 min in the en bloc group (P<0.02), and 51 +/- 6 min in the liver only group (P<0.02). There was no difference in donor age, cold ischemia time, or recipient United Network for Organ Sharing status. Pancreata obtained using the en bloc technique all had immediate function and there were no episodes of acute pancreatitis. Early liver graft function, as assessed by lactate dehydrogenase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, and total bilirubin levels, was significantly lower in the en bloc and liver only group when compared with the in situ group. The total hospital stay was also significantly lower in these groups. We conclude that the rapid en bloc technique decreases operative time during the donor operation. Procurement-related injury to the liver graft is minimized without compromising pancreas graft function.

Vascular complications after pediatric liver transplantation

From February 1986 to July 1994, 81 hepatic transplantations were performed in 73 children, with an overall patient survival rate of 83%. Forty-two patients received whole-liver grafts (WLG) and 39 had reduced-size grafts (RSG). The mean patient weight was 19.7 kg, with 29 patients weighing less than 10 kg. Seventeen vascular complications (21%) occurred in 13 children: 8 (10%) had hepatic artery thrombosis (HAT), 5 (6%) had portal vein thrombosis (PVT), 1 had both HAT and PVT (1%), and 3 (4%) had aortic conduit perforation (ACP). There was no significant difference in the incidence of HAT between RSG (5%) and WLG (14%) or between children weighing less than 10 kg (10%) and those weighing more than 10 kg (10%). The site of arterial reconstruction, end-to-end to the recipient common hepatic artery or end-to-side to the infrarenal aorta, had no significant effect on the occurrence of HAT (7% v 8%), but HAT occurred in 2 of 6 cases (33%) in which an aortic conduit was used. PVT documented in 5 cases (6%) was associated with technical complications (2), preduodenal portal vein (2), and a circulating cardiolipid antibody (1), and required thrombectomy, with no graft loss. Combined HAT and PVT was found in one patient 2 years postretransplantation for HAT. Although graft function is normal, portal hypertension persists. The aortic conduit, used in six patients, led to arterial perforation (3), HAT (2), and death (2). Of the 8 cases of HAT, 1 was diagnosed during autopsy and 7 occurred within 30 days and required retransplantation (6) or thrombectomy with rearterialization (1).(ABSTRACT TRUNCATED AT 250 WORDS)