Long-term results of urgent revascularization for hepatic artery thrombosis after pediatric liver transplantation

Treatment strategies for hepatic artery complications after pediatric liver transplantation: A systematic review

This study aimed to evaluate the effectiveness of different treatments for hepatic artery thrombosis (HAT) and hepatic artery stenosis (HAS) after pediatric liver transplantation. We systematically reviewed studies published since 2000 that investigated the management of HAT and/or HAS after pediatric liver transplantation. Studies with a minimum of 5 patients in one of the treatment methods were included. The primary outcomes were technical success rate and graft and patient survival. The secondary outcomes were hepatic artery patency, complications, and incidence of HAT and HAS. Of 3570 studies, we included 19 studies with 328 patients. The incidence was 6.2% for HAT and 4.1% for HAS. Patients with an early HAT treated with surgical revascularization had a median graft survival of 45.7% (interquartile range, 30.7%-60%) and a patient survival of 61.3% (interquartile range, 58.7%-66.9%) compared with the other treatments (conservative, endovascular revascularization, or retransplantation). As for HAS, endovascular and surgical revascularization groups had a patient survival of 85.7% and 100% (interquartile range, 85%-100%), respectively. Despite various treatment methods, HAT after pediatric liver transplantation remains a significant issue that has profound effects on the patient and graft survival. Current evidence is insufficient to determine the most effective treatment for preventing graft failure.

The Impact of Hepatic Artery Thrombosis on the Outcome of Pediatric Living Donor Liver Transplantations

The aim of our study was to assess risk factors for hepatic artery thrombosis (HAT) and to evaluate the impact of HAT management on long-term outcomes after pediatric living donor liver transplantation (LDLT). We retrospectively analyzed 400 patients who underwent primary LDLT between 1999 and 2020. We compared preoperative data, surgical factors, complications, and patient and graft survivals in patients with HAT (HAT Group) and without HAT (non-HAT Group). A total of 27 patients (6.75%) developed HAT. Acute liver failure, a hepatic artery (HA) anastomosis diameter below 2 mm, and intraoperative HA flow dysfunction were significantly more common in the HAT Group (p < 0.05, p = 0.02026, and p = 0.0019, respectively). In the HAT Group, 21 patients (77.8%) underwent urgent surgical revision. The incidence of biliary stenosis and retransplantation was significantly higher in the HAT Group (p = 0.00002 and p < 0.0001, respectively). Patient and graft survivals were significantly worse in the HAT Group (p < 0.05). The close monitoring of HA flow with Doppler ultrasound during the critical period of 2 to 3 weeks after LDLT and the immediate attempt of surgical revascularization may attenuate the elevated risk of biliary stenosis, graft loss, and the need for retransplantation due to HAT.

Long-Term Survival Outcomes beyond the First Year after Liver Transplantation in Pediatric Acute Liver Failure Compared with Biliary Atresia: A Large-Volume Living Donor Liver Transplantation Single-Center Study

Pediatric acute liver failure (PALF) is a common cause of liver transplantation (LT) but showed poor post-LT outcomes. We reviewed 36 PALF patients and 120 BA patients who underwent LT in our institution. The cause of PALF was unknown in 66.7%. PALF patients were older (6.2 vs. 2.9 years) with higher PELD scores (31.5 vs. 24.4) and shorter waitlist time (15.7 vs. 256.1 days) (p < 0.01). PALF patients showed higher rates of post-transplant renal replacement therapy (RRT) (13.9% vs. 4.2%) and hepatic artery complications (13.9% vs. 0.8%), while portal vein complications rates were lower (0% vs. 10.8%), (p < 0.05). Although PALF patients showed lower 5-year survival rates (77.8% vs. 95.0 %, p < 0.01), the 5-year survival rates of patients who lived beyond the first year were comparable (96.6% vs. 98.3%, p = 0.516). The most common cause of deaths within one year was graft failure (75.0%) in PALF patients, but infection (67.7%) in BA patients. In multivariate analysis, lower body weight, hepatic artery complications and post-transplant RRT were associated with worse survival outcomes (p < 0.05). In conclusion, physicians should be alert to monitor the immediate postoperative graft dysfunction and hepatic artery complications and patients on post-transplant RRT in order to improve survival outcomes in PALF patients.

Microsurgical replacement of the right hepatic artery with the donor superior mesenteric artery in cadaveric donor pediatric liver transplantation

PURPOSE

To present our experience of using the pediatric donor superior mesenteric artery (SMA) as the interpositioning vessel to reconstruct the hepatic artery in pediatric deceased donor liver transplantation.

METHODS

Pediatric patients who received pediatric deceased donor livers from December 2019 to June 2021 were enrolled.

RESULTS

A total of 43 pediatric recipients received pediatric deceased donor livers during the study period. Thirty-four (79.1%) pediatric donors had normal hepatic artery anatomy, while nine (20.9%) showed variant anatomies. The SMAs of the pediatric donors were interposed in the latter eight cases. The anastomosis between the donor distal SMA and the donor celiac trunk artery (CTA) was initially performed in the back-table period, after which the other anastomosis between the donor proximal SMA and recipient CHA was performed. Only one case showed HAT occurrence (incidence rate, 2.3%). However, no arterial complications occurred in pediatric recipients with donor grafts that showed the variation of RHA replacement from the SMA and had undergone usage of the donor's SMA as an interpositioning vessel.

CONCLUSIONS

In pediatric deceased donor liver transplantation, the use of SMA as an interpositioning medium can solve the problems related to a tiny caliber and anatomical variations of the donor hepatic artery.

Early hepatic arterial thrombosis in liver transplantation: Systemic intravenous alteplase as a potential rescue treatment after failed surgical revascularization

eHAT is one of the most dreaded post-LT complication. Treatment approaches include retransplantation, revascularization, or observation. Systemic thrombolytic therapy is used in pediatric patients with thromboembolic events. However, there is no previous study reporting on the use of systemic r-tPA to treat eHAT. The treatment strategies used in patients with eHAT are described, focusing on two children who failed SR and were treated with systemic heparinization plus systemic r-tPA infusion. r-tPA-RP consists of intravenous systemic infusion at a dose of 0.3 mg/kg/h during 6 hours, for 5 days. First case (3-year) was transplanted with a whole liver, and second case (6-year) received a LLS from a living donor. HAT was diagnosed by doppler US and confirmed by angioCT scan in both patients in the first day after LT. They underwent SR and were clinically stable. Re-thrombosis occurred in both patients the day after, and r-TPA-RP was started-one patient required two r-TPA-RP for HAT recurrence. They presented minor bleeding, without repercussion. Hepatic artery recanalized after 10 and 3 days in the first and second patient, respectively. Retransplant was avoided, and one developed biliary strictures, successfully managed in the follow-up. r-TPA-RP avoided retransplantation after eHAT in these cases. To our knowledge, this is the first report of the use of systemic r-TPA to treat eHAT in children. This strategy may compose an algorithm to treat eHAT that failed SR in stable patients.

Management and outcome of hepatic artery thrombosis after pediatric liver transplantation

BACKGROUND

Pediatric LT are at particular risk of HAT, and its management still constitutes a matter of debate. Our purpose was to study predisposing factors and outcome of HAT post-LT, including the impact of surgical revisions on survival and biliary complications.

METHODS

Among 882 primary pediatric LT performed between 1993 and 2015, 36 HAT were encountered (4.1%, 35 fully documented). Each HAT case was retrospectively paired with a LT recipient without HAT, according to diagnosis, age at LT, type of graft, and era.

RESULTS

Five-year patient survivals were 77.0% versus 83.9% in HAT and non-HAT paired groups, respectively (P = .321). Corresponding graft survivals were 20.0% versus 80.5% (P < .001), and retransplantation rates 77.7% versus 10.7%, respectively (P < .001). One-year biliary complication-free survivals were 16.6% versus 83.8% in the HAT and non-HAT groups, respectively (P < .001). Regarding chronology of surgical re-exploration, only HAT cases that occurred within 14 days post-LT were re-operated, fourteen of them being explored within 7 days post-LT (revascularization rate: 6/14), versus two beyond 7 days (no revascularization). When revascularization was achieved, graft and biliary complication-free survival rates at 1 year were 33.3% and 22.2%, respectively, both rates being 0.0% in case of failure.

CONCLUSIONS

The pejorative prognosis associated with HAT in terms of graft survival is confirmed, whereas patient survival could be preserved through retransplantation. Results suggest that HAT should be re-operated if occurring within 7 days post-LT, but not beyond.

Time is of the essence: A single-center experience of hepatic arterial supply impairment management in pediatric liver transplant recipients

BACKGROUND

Impairment of hepatic arterial flow including hepatic arterial thrombosis (HAT), hepatic arterial stenosis (HAS), and splenic artery steal syndrome (SASS) is potentially life-threatening complications. The proposed early diagnosis and urgent treatment strategy of graft arterial flow reduction aim to decrease morbidity and mortality.

METHODS

Pediatric patients with known hepatic arterial flow impairment were retrospectively reviewed. Patients were grouped by occlusive (HAT) and non-occlusive (HAS/SASS) arterial flow reduction. Patients with HAT were further divided in two groups based on the estimated maximal hepatic artery occlusion time ≤8 and >8 hours.

RESULTS

Impairment of hepatic arterial flow developed in 32 of 416 pediatric liver transplant recipients. HAT, HAS, and SASS incidences were 4.1% (n = 17), 2.2% (n = 9), and 1.4% (n = 6), respectively. Neither graft loss nor death occurred in the non-occlusive group. The probabilities of sepsis (OR, 1.7; 95% CI, 1.14-2.53; P=.008) and graft loss or death (OR, 1.42; 95% CI, 1.04-1.92; P=.046) were higher in the occlusive group. Patients with estimated maximal duration of hepatic artery occlusion ≤ 8 hours (n = 7; 41.2%) did not have ischemic-type biliary lesions and sepsis (P=.044 and 0.010, respectively) but had excellent 3-year graft survival compared with > 8 hours group (100% vs 40%; P=.037). Multivariate analysis revealed HAT manifestation by fever was associated with increased chances of graft loss or death.

CONCLUSION

Occlusive arterial complications impose higher risks of graft loss and death. Thorough arterial supply monitoring by Doppler ultrasonography and urgent endovascular arterial flow restoration may salvage both graft and the recipient.

Decreased Incidence of Hepatic Artery Thrombosis in Pediatric Liver Transplantation Using Technical Variant Grafts: Report of the Society of Pediatric Liver Transplantation Experience

OBJECTIVE

To evaluate risk factors for hepatic artery thrombosis (HAT) and examine the long-term outcomes of graft and patient survival after HAT in pediatric recipients of liver transplantation.

STUDY DESIGN

Using multicenter data from the Society of Pediatric Liver Transplantation, Kaplan-Meier and Cox regression analyses were performed on first-time pediatric (aged <18 years) liver transplant recipients (n = 3801) in the US and Canada between 1995 and 2016.

RESULTS

Of children undergoing their first liver transplantation, 7.4% developed HAT within the first 90 days of transplantation and, of those who were retransplanted, 20.7% developed recurrent HAT. Prolonged warm ischemia times increased the odds of developing HAT (OR, 1.11; P = .02). Adolescents aged 11-17 years (OR, 0.53; P = .03) and recipients with split, reduced, or living donor grafts had decreased odds of HAT (OR, 0.59; P < .001 compared with whole grafts). Fifty percent of children who developed HAT developed graft failure within the first 90 days of transplantation (adjusted hazard ratio, 11.87; 95% CI, 9.02-15.62) and had a significantly higher post-transplant mortality within the first 90 days after transplantation (adjusted hazard ratio, 6.18; 95% CI, 4.01-9.53).

CONCLUSIONS

These data from an international registry demonstrate poorer long-term graft and patient survival in pediatric recipients whose post-transplant course is complicated by HAT. Notably, recipients of technical variant grafts had lower odds of HAT compared with whole liver grafts.

Liver Transplantation for Propionic Acidemia: Evidence from A Systematic Review and Meta-analysis

BACKGROUND

The worldwide experience of liver transplantation (LT) in the treatment of propionic acidemia (PA) remains limited and fragmented. This review aims to provide a comprehensive and quantitative understanding of post-transplant clinical outcomes in PA patients.

METHODS

MEDLINE, Embase and the Cochrane Library databases were searched for studies focusing on PA patients who underwent LT. The pooled estimate rates and 95% confidence intervals (CIs) were calculated using a random-effects model with Freeman-Tukey double arcsine transformation.

RESULTS

Twenty-one studies involving 70 individuals were included. The pooled estimate rates were 0.95 (95% CI, 0.80-1.00) for patient survival and 0.91 (95% CI, 0.72-1.00) for allograft survival. The pooled estimate rates were 0.20 (95% CI, 0.05-0.39) for rejection, 0.08 (95% CI, 0.00-0.21) for hepatic artery thrombosis, 0.14 (95% CI, 0.00-0.37) for cytomegalovirus/Epstein-Barr virus infection and 0.03 (95% CI, 0.00-0.15) for biliary complications. The pooled estimate rates were 0.98 (95% CI, 0.88-1.00) for metabolic stability, 1.00 (95% CI, 0.79-1.00) for reversal of pre-existing cardiomyopathy and 0.97 (95% CI, 0.78-1.00) for improvement of neurodevelopmental delay. A large proportion of patients achieved liberalization of protein intake posttransplant [pooled estimate rate 0.66 (95% CI, 0.35-0.93)].

CONCLUSIONS

Despite the risk of transplant-related complications, LT is a viable therapeutic option in PA patients, with satisfactory survival rates and clinical outcomes. Given the diversity in neurological assessment methods and the inconsistency in achievement of dietary protein liberalization across different studies, consensus on neurological evaluation methods and post-transplant protein intake is necessary. Longer-term clinical outcomes of LT for PA warrants further investigation.

Donor-to-recipient weight ratio is a risk factor for hepatic artery thrombosis after whole-liver transplantation in children under 25 kg

Hepatic artery thrombosis (HAT) following pediatric liver transplantation increases morbidity and risk of graft failure. We performed a retrospective chart review of all patients who underwent deceased-donor liver transplantation from August 2002 to July 2016. Multi-organ transplant recipients were excluded. We examined the incidence of HAT at our institution and sought to identify associated donor or recipient risk factors. A total of 127 deceased-donor liver transplant patients with a median age of 1.7 years (IQR 0.67-6.7) were identified. Of those, 14 developed HAT, all weighing under 25 kg. Among 100 patients under 25 kg, whole-liver graft recipients had an odds ratio of 3.98 (95% confidence interval [CI]: 1.03, 15.34; P = .045) for developing HAT compared with split-liver graft recipients. Within the whole-liver recipient group under 25 kg, 11 patients developed HAT with a median donor-to-recipient ratio (DRWR) of 0.9 (IQR: 0.7-1.2) compared with a median DRWR of 1.4 (IQR: 1.1-1.9) for those who did not develop HAT. Multivariate analysis showed DRWR to be an independent risk factor for HAT in patients weighing under 25 kg who received whole organ grafts, with an odds ratio of 3.89 (95% CI: 1.43, 10.54; P = .008) for each 0.5 unit decrease in DRWR. Our results suggest that in recipients under 25 kg 1) split-liver grafts may have a lower rate of HAT and 2) selecting whole organ donors with a higher DRWR may decrease the incidence of HAT.

Outcomes of Liver Transplantation in Small Infants

Liver transplantation (LT) for small infants remains challenging because of the demands related to graft selection, surgical technique, and perioperative management. The aim of this study was to evaluate the short-term and longterm outcomes of LT regarding vascular/biliary complications, renal function, growth, and patient/graft survival in infants ≤3 months compared with those of an age between >3 and 6 months at a single transplant center. A total of 64 infants ≤6 months underwent LT and were divided into 2 groups according to age at LT: those of age ≤3 months (range, 6-118 days; XS group, n = 37) and those of age >3 to ≤6 months (range, 124-179 days; S group, n = 27) between 1989 and 2014. Acute liver failure was the main indication for LT in the XS group (n = 31, 84%) versus S (n = 7, 26%). The overall incidence of hepatic artery thrombosis and portal vein thrombosis/stricture were 5.4% and 10.8% in the XS group and 7.4% and 11.1% in the S group, respectively (not significant). The overall incidence of biliary stricture and leakage were 5.4% and 2.7% in the XS group and 3.7% and 3.7% in the S group, respectively (not significant). There was no significant difference between the 2 groups in terms of renal function. No significant difference was found between the 2 groups for each year after LT in terms of height and weight z score. The 1-, 5-, and 10-year patient survival rates were 70.3%, 70.3%, and 70.3% in the XS group compared with 92.6%, 88.9%, and 88.9% in the S group, respectively (not significant). In conclusion, LT for smaller infants has acceptable outcomes despite the challenges of surgical technique, including vascular reconstruction and graft preparation, and perioperative management.

Hepatic artery reconstruction with interposition of donor's right gastroepiploic artery graft in pediatric living donor liver transplantation for metabolic disease

OBJECTIVE

We introduce the indications, technique, results of our experience using donor's RGEA as interposition vessel to solve hepatic artery reconstruction problems in P-LDLT.

METHODS

A retrospective analysis of P-LDLT for children with metabolic diseases from June 2013 to November 2018 in our center was carried out. The arterial conditions, reconstruction methods, and prognosis were analyzed.

RESULTS

A total of 73 children with metabolic diseases underwent P-LDLT during the period. The LLF was the main graft, accounting for 71.2%. The donor's RGEA was utilized in five cases. There were three children with OTCD and two children with deficiency of CPS1 and MSUD, respectively. In three cases, the grafts' left hepatic arteries were anastomosed with the recipients' PHA using donors' RGEA as interposition vessel. In other two cases, the donors' RGEA was interposed between graft's MHA and the recipient's bifurcation of PHA and GDA. The average follow-up time was 19.7 ± 15.9 month. There were two cases of artery thrombosis or occlusion, and the incidence was 2.7%. No arterial complications occurred in children using RGEA (follow-up time 5.0 ± 3.4 months).

CONCLUSION

In P-LDLT for patients with metabolic diseases, the application of RGEA as an interposition vessel can solve caliber mismatch and short arteries problem and achieve good results. Compared with traditional arterial anastomosis, it may reduce the incidence of arterial complications.

Thrombosis prophylaxis in pediatric liver transplantation: A systematic review

AIM

To review current literature of thrombosis prophylaxis in pediatric liver transplantation (PLT) as thrombosis remains a critical complication.

METHODS

Studies were identified by electronic search of MEDLINE, EMBASE and Cochrane Library (CENTRAL) databases until March 2018. The search was supplemented by manually reviewing the references of included studies and the references of the main published systematic reviews on thrombosis and PLT. We excluded from this review case report, small case series, commentaries, conference abstracts, papers which describing less than 10 pediatric liver transplants/year and articles published before 1990. Two reviewers performed study selection independently, with disagreements solved through discussion and by the opinion of a third reviewer when necessary.

RESULTS

Nine retrospective studies were included in this review. The overall quality of studies was poor. A pooled analysis of results from studies was not possible due to the retrospective design and heterogeneity of included studies. We found an incidence of portal vein thrombosis (PVT) ranging from 2% to 10% in pediatric living donor liver transplantation (LDLT) and from 4% to 33% in pediatric deceased donor liver transplantation (DDLT). Hepatic artery thrombosis (HAT) was observed mostly in mixed LDLT and DDLT pediatric population with an incidence ranging from 0% to 29%. In most of the studies Doppler ultrasonography was used as a first line diagnostic screening for thrombosis. Four different surgical techniques for portal vein anastomosis were reported with similar efficacy in terms of PVT reduction. Reduced size liver transplant was associated with a low risk of both PVT (incidence 4%) and HAT (incidence 0%, P < 0.05). Similarly, aortic arterial anastomosis without graft interposition and microsurgical hepatic arterial reconstruction were associated with a significant reduced HAT incidence (6% and 0%, respectively). According to our inclusion and exclusion criteria, we did not find eligible studies that evaluated pharmacological prevention of thrombosis.

CONCLUSION

Poor quality retrospective studies show the use of tailored surgical strategies might be useful to reduce HAT and PVT after PLT; prospective studies are urgently needed.

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.

Management of early hepatic artery occlusion after liver transplantation with failed rescue

Hepatic artery thrombosis is a serious complication after liver transplantation which often results in biliary complications, early graft loss, and patient death. It is generally thought that early hepatic artery thrombosis without urgent re-vascularization or re-transplantation almost always leads to mortality, especially if the hepatic artery thrombosis occurs within a few days after transplantation. This series presents 3 cases of early hepatic artery thrombosis after living donor liver transplantation, in which surgical or endovascular attempts at arterial re-vascularization failed. Unexpectedly, these 3 patients survived with acceptable graft function after 32 mo, 11 mo, and 4 mo follow-up, respectively. The literatures on factors affecting this devastating complication were reviewed from an anatomical perspective. The collective evidence from survivors indicated that modified nonsurgical management after liver transplantation with failed revascularization may be sufficient to prevent mortality from early hepatic artery occlusion. Re-transplantation may be reserved for selected patients with unrecovered graft function.

Vascular complications in biliary atresia patients undergoing living donor liver transplantation: Analysis of 110 patients over 10 years

Introduction:

Vascular complications are very common in pediatric living donor liver transplants. We present our experience in vascular complications in biliary atresia patients undergoing liver transplantation.

Materials and Methods:

All the patients who have undergone living donor liver transplant for biliary atresia from January 2003 to March 2013 were retrospectively analyzed. P value < 0.05 was considered to be statistically significant.

Results:

Total 110 patients have undergone living donor liver transplantation for biliary atresia between January 2003 and March 2013. There were 56 males and 54 females. Median age at transplant was 13.5 months. Eleven were primary transplants and 99 were post KASAI procedure. One hundred left lateral, four left lobe, and four right lobe grafts were used. Twenty-two patients developed vascular complications. Twelve patients developed hepatic artery thrombosis. Eleven patients of hepatic artery thrombosis were managed with redo hepatic artery anastomosis and one patient managed with radial artery interposition graft. Five patients developed portal vein stenosis and were managed by portal vein stenting. Five patients developed portal vein thrombosis and portal vein thrombectomy and re-anastomosis were done. One patient developed stenosis at the site of venous anastomosis and was managed by stenting. One patient developed both hepatic artery thrombosis and portal vein thrombosis and eventually succumbed to these complications. Out of five cases who died in this study, two had vascular complications. Graft/recipient weight ratio (GRWR) greater than 2.5 was significantly associated with vascular complications (P = 0.017).

Conclusion:

Vascular complications are frequently seen in liver transplantation for biliary atresia. Large for size grafts, weight less than 10 kg, age less than 1 year, and prolonged warm ischemia time is significantly associated with vascular complications.

Liver regeneration model in growing rats with hepatic artery ligation: histologic and molecular studies

BACKGROUND

Liver transplantation is an effective treatment for irreversible liver diseases. The incidence of hepatic artery thrombosis remains high. Our objective was to analyze the effect of ligature of the hepatic artery on liver regeneration in a growing animal model.

METHODS

Seventy-five male Wistar rats were divided into the following 3 groups: group 1 (sham, G1): incision without intervention; group 2 (G2): 70% hepatectomy; group 3 (G3): 70% hepatectomy and ligation of the hepatic artery. Preceding the 70% hepatectomy, a hepatic artery ligature was performed with resection of a segment of the artery. The liver specimens were stained with hematoxylin-eosin, and immunohistochemical staining for Ki-67 was performed. The expression of the interleukin (IL) 6 gene was studied by means of reverse-transcription polymerase chain reaction.

RESULTS

G2 and G3 demonstrated similar tendencies toward an increase in the gain weight ratio over time. The mitotic activity was significantly lower at 72 hours in G3 than in G2. There was no difference between Ki-67 staining between G2 and G3. The expression of the IL-6 gene was present in all of the groups, lower in G1, with no difference between G2 and G3.

CONCLUSIONS

The experimental model was feasible and adequate for these investigations. Hepatectomy stimulated hepatocyte proliferation, and the obstruction of the arterial flow did not affect liver regeneration.

Low plasma levels of antithrombin III in the early post-operative period following pediatric liver transplantation: should they be replaced? A single-center pilot study

eHAT after LT remains a life-threatening complication. In the majority of anticoagulation protocols, heparin is used to prevent thromboses. Our study aimed to monitor AT-III levels in the early post-LT period to assess the need for the administration of AT-III concentrate to ensure the effectiveness of heparin. We monitored coagulation daily by measuring INR, APTT, fibrinogen, platelets, and AT-III. Anticoagulation therapy consisted of LMWH, AT-III, and dipyridamole. AT-III concentrate was administered when AT-III activity was ≤60%. DUS was performed daily for the first five post-operative days or whenever vascular thrombosis was suspected. Between October 2007 and October 2011, 39 LT were performed in our center. The median age was 26 months (6-196) with a median weight of 9 kg (5.5-49). AT-III activity was ≤60% in 27 patients. Lower levels were particularly observed in partial grafts and recipients weighing less than 10 kg. Patent arterial flow was present in all 39 LT during the first five post-operative days. AT-III levels were low in 70% of pediatric patients following LT, thereby risking heparin ineffectiveness. These results may implicate low AT-III levels in the etiology of eHAT post-LT. However, this is a small single-center pilot study and further larger prospective trials are required to confirm these results.

Right-lobe living-donor liver transplantation in adult patients with acute liver failure

BACKGROUND

Right-lobe living-donor liver transplantation (RLDLT) is an excellent option to reduce donor shortages for adult patients with acute liver failure (ALF). The aim of this study was to evaluate the etiologies and outcomes of 30 consecutive adult patients who underwent emergency RLDLT for ALF.

METHODS

Between January 2007 and September 2011, we examined data from medical records of patients with ALF who underwent RLDLT.

RESULTS

Their mean age was 32.2 ± 13.05 years. The etiologies of ALF were acute hepatitis B (n = 11; 36.6%), hepatitis A (n = 4; 13.3%), drug intoxication (n = 4; 13.3%), pregnancy (n = 2; 6.7%), hepatitis B with pregnancy (n = 1; 3.3%), mushroom intoxication (n = 1; 3.3%), and unknown (n = 7; 23.3%). The mean hepatic coma grade (Model for End-Stage Liver Disease score) was 34.13 ± 8.72. The 43 (48.7%) postoperative complications were minor (grades I-II) and 44 (51.3%) were major (grades III-V). Reoperation was required in 14 of 30 (47%) recipients (grades IIIb-IVa). Deaths occurred owing to pulmonary (n = 2), cardiac (n = 1), septic (n = 2), or encephalopathic (n = 4) complications. The mean durations of intensive care unit stay and postoperative hospitalization were 3.2 ± 2.3 and 29.5 ± 23 days, respectively. The survival rate was 70%. The mean follow-up duration was 305 days (range, 1-1582).

CONCLUSION

Liver transplantation is potentially the only curative modality, markedly improving the prognosis of patients with ALF. The interval between ALF onset and death is short and crucial because of the rapid, progressive multiorgan failure. Thus, RLDLT should be considered to be a life-saving procedure for adult patients with ALF, requiring quicker access to a deceased-donor liver graft and a short ischemia time.

Revision liver transplant for persistent infection and localized aspergillosis after hepatic artery thrombosis

Early hepatic artery thrombosis after liver transplant may be complicated by aggressive aspergillosis and bacterial infections that may cause morbidity and mortality. The definitive treatment of hepatic artery thrombosis is revision transplant. However, sepsis may be a contraindication to revision transplant. A 37-year-old man developed hepatic artery thrombosis at 3 days after liver transplant. During the treatment of hepatic artery thrombosis, he developed multiple biliary, bacterial, and fungal infections. Evaluation showed aspergillosis with multiple intrahepatic abscesses. He was treated with antibiotic and antifungal drugs. Despite active sepsis, revision transplant was performed and the infection resolved. Although sepsis may be a contraindication for transplant surgery, revision transplant was successful, probably because the primary transplanted liver was the source of infection.

Risk factors and treatments for hepatic arterial complications in pediatric living donor liver transplantation

BACKGROUND

Hepatic artery complications (HAC) are a serious complication in pediatric liver transplant recipients because its incidence is high and it can occasionally lead to graft liver failure. We herein present a retrospective analysis of our 10-year experience with pediatric living donor liver transplantation (LDLT) focusing on the risk factors and treatments for HAC.

METHODS

Between May 2001 and November 2011, 209 LDLTs were performed for 203 pediatric recipients. We performed the multivariate analyses to identify the factors associated with HAC and showed the therapeutic strategy and outcome for HAC.

RESULTS

The overall incidence of HAC was 7.2%, and the graft survival of recipients with HAC was 73.3%. The multivariate analysis showed that the pediatric end-stage liver disease score (≥20), post-transplant laparotomy except for HAC treatment and extra-anatomical hepatic artery reconstruction were independent risk factors for HAC (P = 0.020, P = 0.015 and P = 0.002, respectively). Eleven surgical interventions and 13 endovascular interventions were performed for 15 recipients with HAC. The serum aspartate aminotransferase levels pre- and post-treatment for HAC were significantly higher in the surgical group than in the endovascular group (P = 0.016 and P = 0.022, respectively).

CONCLUSIONS

It is important for recipients with risk factors to maintain strict post-transplant management to help prevent HAC and detect it in earlier stages. Endovascular intervention can be a less invasive method for treating HAC than surgical intervention, and can be performed as an early treatment.

A comparison of open surgery and endovascular intervention for hepatic artery complications after pediatric liver transplantation

There are currently 2 major therapeutic options for the treatment of hepatic artery complications: endovascular intervention and open surgery. We herein report a retrospective analysis of 14 pediatric patients with hepatic artery complications after pediatric living donor liver transplantation (LDLT) at our institution. We divided them into an open surgery group and an endovascular intervention group based on their primary treatment, and compared the results and outcomes. We then evaluated which procedure is more effective and less invasive. In the open surgery group, recurrent stenosis or spasm of the hepatic artery occurred in 3 of the 8 patients (37.5%). In the endovascular intervention group, 5 of the 6 patients were technically successfully treated by only endovascular treatment. Of the 5 successfully treated patients, 3 developed recurrent stenosis (60%). There were significant differences in the mean length of the operation for the first treatment of hepatic artery complications (open surgery, 428 minutes vs endovascular intervention, 160 minutes; P = .01) and in the mean value of the posttreatment aspartate aminotransferase (AST)/alanine aminotransferase (ALT) (open surgery > endovascular intervention; P = .04/.05). Although endovascular intervention needs to be examined in further studies to reduce the rate of relapse, it is a less invasive method for the patient and graft than open surgery.

Clinical experience with microdialysis catheters in pediatric liver transplants

Ischemic vascular complications and rejection occur more frequently with pediatric liver transplants versus adult liver transplants. Using intrahepatic microdialysis catheters, we measured lactate, pyruvate, glucose, and glycerol values at the bedside for a median of 10 days in 20 pediatric liver grafts. Ischemia (n = 6), which was defined as a lactate level > 3.0 mM and a lactate/pyruvate ratio > 20, was detected without a measurable time delay with 100% sensitivity and 86% specificity. Rejection (n = 8), which was defined as a lactate level > 2.0 mM and a lactate/pyruvate ratio < 20 lasting for 6 or more hours, was detected with 88% sensitivity and 45% specificity. With additional clinical criteria, the specificity was 83% without a decrease in the sensitivity. Rejection was detected at a median of 4 days (range = 1-7 days) before alanine aminotransferase increased (n = 5, P = 0.11), at a median of 4 days (range = 2-9 days) before total bilirubin increased 25% or more (n = 7, P = 0.04), and at a median of 6 days (range = 4-11 days) before biopsy was performed (n = 8, P = 0.05). In conclusion, microdialysis catheters can be used to detect episodes of ischemia and rejection before current standard methods in pediatric liver transplants with clinically acceptable levels of sensitivity and specificity. The catheters were well tolerated by the children, and no major complications related to the catheters were observed.

Hepatic artery kinking during liver transplantation: survey and prospective intraoperative flow measurement

BACKGROUND

Hepatic artery thrombosis (HAT) represents the most common vascular complication occurring after liver transplantation (LT). Herein, we report the results of a prospective study of hepatic artery flow (HAF) measurement during abdominal wall closure after LT along with the results of an international survey of procedures adopted, in order to avoid the arterial kinking (AK) in case of long artery.

METHODS

Sixty-four surgeons were asked regarding the different procedures used to avoid AK in the presence of long artery. We prospectively assessed the HAF during three phases of LT in 26 consecutive LT performed in patients with a long HA: after completion of the biliary anastomosis (M0), and partial abdominal wall closure with (M1w) or without (M1w/o) hepatic artery anti-kinking method (HAAK).

RESULTS

Sixty (93.7 %) surgeons replied to the survey: 44 (73.3 %) surgeons cut the artery as short as possible, of whom 38 (86.3 %) interposed an oxidized polymer or the omentum, and six (13.7 %) used other systems. Fourteen (23.3 %) surgeons did not use any interposition methods. The remaining two (3.3 %) surgeons left a long artery without HAAK. In our cohort we obtained the following HAF measures: M0 152 mL/min (89-205), M1 without HAAK 114 (66-168) and M1 with HAAK procedure 158 (91-219) (p = 0.002).

CONCLUSIONS

Our survey confirms that no consensus is currently available regarding the most effective method for avoiding AK. Kinking occurs most probably when the liver is released in its final position. The utilization of an interposition method could ensure the maintenance of a correct HAF.

The long-term outcome of hepatic artery thrombosis after liver transplantation in children: role of urgent revascularization

Hepatic artery thrombosis (HAT), one of the most severe complications of pediatric orthotopic liver transplantation (OLT), often compromises graft and/or child survival. Of 590 OLT performed in 516 children over a 20-year period, 45 were complicated by early HAT, during the first 2 weeks after transplantation. Systematic Doppler ultrasonographic detection of HAT allowed successful surgical revascularization in 19 instances, resulting in a 20-year graft survival rate of 77% versus 24% of cases when revascularization was not attempted or failed. A combination of surgical emergency revascularization, biliary interventional radiology, biliary surgery and/or retransplantation resulted in an 80% 20-year patient survival rate, identical to that of transplanted children who did not experience early HAT. The majority of long-term survivors with their initial graft had normal liver tests, no biliary dilation on ultrasonography and minimal or moderate fibrosis on liver histology. A failed attempt at revascularization did not significantly alter patient survival. Despite these encouraging results, for the children and their parents to overcome the entire process in terms of reoperations, repeated radiological interventions, number of hospitalizations and emotional stress, remains an ordeal of such magnitude that it justifies renewed efforts to progress in the prevention of this complication.

Living donor liver transplantation in 43 children with biliary atresia: a single-center experience from the mainland of China

BACKGROUND

There is no large-cohort report on living donor liver transplantation (LDLT) for biliary atresia (BA) patients from the mainland of China. This single-center study describes our initial experience with 43 LDLTs for BA patients aged two years or younger.

METHODS

In this study, the eligibility criteria were BA as the primary diagnosis and two years of age or younger. From October 2006 to December 2010, the clinical data of 43 LDLTs, including pre-operative evaluations, surgical techniques, postoperative complications and outcomes of donors and recipients, were retrospectively analyzed.

RESULTS

Donor graft type was the left lateral segment with compatible ABO blood groups. Forty-three recipients were selected in this study. The median patient age at operation was 9 months (range 6-24), and the median body weight was 8 kg (range 5.7-12.5). Fourteen (32.6%) recipients received Kasai operations before liver transplantation. The overall one- and two-year cumulative survival rates for grafts and recipients were 81%, 81% and 76%, 76%, respectively. No donor mortality was encountered, with a minimal morbidity and no long-term sequelae. Nine out of 43 recipients died. Postoperative complications of recipients were biliary leakage and refluxing cholangitis (11/43, 25.6%), hepatic artery thrombosis (4, 9.3%), pulmonary infections (4, 9.3%), portal vein thrombosis (3, 7.0%), wound disruption (3, 7.0%), acute rejection (3, 7.0%), cytomegalovirus infection (2, 4.7%), and intra-abdominal bleeding (1, 2.3%).

CONCLUSION

Despite the relatively low survival rates due to lack of experience initially, LDLT still provides encouraging outcomes for pediatric recipients with BA, even small children under two years old.

Liver transplantation in Indian Armed Forces-initial experience

BACKGROUND

This study retrospectively analyses the initial experience of liver transplantation (LT) in the Indian Armed Forces.

METHODS

Fifty-three patients underwent LT at Army Hospital (R&R) Delhi Cantt. between March 2007 and March 2011. Of these 35 patients underwent deceased donor liver transplantation (DDLT) and living donor liver transplantation (LDLT) was carried out in 18 patients. The surgical techniques, complications and mortality were analysed.

RESULTS

A high consent rate of 35.9% for organ donation was achieved by the Armed Forces Organ Retrieval and Transplantation Authority (AORTA). Biliary complications occurred in five patients (9.4%). However, most of them could be managed by endoscopic interventions. Hepatic artery thrombosis (HAT) occurred in five patients (9.4%). Of these, two DDLT grafts were revascularised following HAT, by creating extra-anatomic arterial conduits with excellent outcome. The overall mortality was 18.8% (n = 10). There was no significant difference in the overall complications or mortality in patients undergoing DDLT or LDLT.

CONCLUSION

The overall survival and morbidity in this study is comparable to those from other centres. Urgent revascularisation of grafts following HAT should be attempted as it can salvage grafts with satisfactory outcome. There is a reduction in the incidence of biliary complications with refinements in surgical techniques.

Predictors of long-term outcome after liver transplant

Liver transplantation is the standard of care for children with life-threatening liver disease. Survival rates posttransplantation are rising with current 1-year and 5-year rates being greater than 90% and 85%, respectively. Numerous factors contribute to posttransplant outcomes of graft and patient survival, including improved surgical techniques, immunosuppressive regimens, and posttransplant management. The present review aims to discuss predictors of long-term outcomes of pediatric transplant recipients and identify potential risk factors.

Liver transplantation in children weighing 5 kg or less: analysis of the UNOS database

LT is a major medical and surgical challenge in very small patients. Aim of the study is to determine the outcomes after LT in infants ≤ 5 kg at transplant in a large cohort of patients.

METHODS

Infants ≤ 5 kg who had LT between 10/1987 and 5/2008 were identified from the UNOS database. Risk factors for death and graft loss were analyzed by multivariate logistic regression.

RESULTS

Of 11,467 children, 570 (5%) were ≤ 5 kg at LT. Mean age and weight at LT were 0.11 ± 0.48 yr, 4.32 ± 0.74 kg, respectively. One- and five-yr patient and graft survival were 77.7%, 72.2% and 66.1%, 57.6%, respectively. The primary cause of death was infection (25.9%). Recipient age was a predictor of graft loss. Patient and graft survival have improved over time. Life support at transplant was identified as a risk factor for both death and graft loss (p < 0.02, p < 0.01, respectively).

CONCLUSION

LT recipients ≤5 kg have high mortality and graft loss. Over time, graft survival has improved, although it is still inferior to the overall reported outcomes of pediatric LT. Being on life support at transplant is a significant risk factor for death and graft loss in very small recipients.

Pediatric liver transplantation: A report from a pediatric surgical unit

BACKGROUND

Liver transplantation is well established worldwide as an effective treatment for end-stage liver disease in children. Acceptance in India has been slow because of considerations of cost, infections, inability to support long-term care, and non-availability of expertise.

AIM

This study was designed to report our experience with pediatric liver transplantation.

MATERIALS AND METHODS

Twenty-eight children underwent liver transplantation.

RESULTS

Biliary atresia was the commonest indication (n = 15) followed by metabolic liver disease. Twenty-six children had living donor transplants, mothers being the donors in a majority of these. Common surgical complications included bile leaks (n = 3) and vascular problems (n = 6). Common medical complications included infections, acute rejection, and renal failure. Overall, patient survival was 71%, while that for the last 14 cases was 92%. All survivors are doing well, have caught up with physical and developmental milestones and are engaged in age appropriate activities.

CONCLUSIONS

The study demonstrates the feasibility of a successful pediatric liver transplant program in our country.

Liver transplantation and spontaneous neovascularization after arterial thrombosis: "the neovascularized liver"

The only arterial pathway available after liver transplantation is the hepatic artery. Therefore, hepatic artery thrombosis can result in graft loss necessitating re-transplantation. Herein, we present evidence of neovascularization at long-term follow-up in a series of transplant patients with hepatic artery thrombosis. We termed this phenomenon "neovascularized liver". Hepatic artery thrombosis was noted in 30/407 cases (7.37%), and occurred early in 13 patients (43.3%) and late (>30 days) in 17 (56.7%) patients. At the time of this study, 11 (36.7%) patients had a neovascularized liver. Those patients with neovascularized liver and normal liver function were closely followed. Of these patients, 10 (91%) showed evidence of neovascularized liver by imaging, and an echo-Doppler arterial signal was recorded in all patients. The mean interval between the diagnosis of hepatic artery thrombosis and neovascularized liver was 4.1 months (range of 3-5.5 months). Liver histology showed an arterial structure in 4 (36.4%) patients. Four factors were associated with development of neovascularized liver: late hepatic artery thrombosis, early hepatic artery stenosis, site of thrombosis, and Roux-en-Y anastomosis. The overall survival rate at 54 months was 90.9%. In conclusion, a late hepatic artery thrombosis may be quite uneventful and should not automatically lead to re-transplantation.