Diagnosis and treatment of pediatric patients with late-onset portal vein stenosis after living donor liver transplantation

Balloon angioplasty versus stent placement for the treatment of portal vein stenosis in children: a single center experience

PURPOSE

To evaluate the safety and efficacy of percutaneous interventional treatment of portal vein stenosis in children.

MATERIAL AND METHODS

A retrospective analysis of all interventional treatments for portal vein stenosis in pediatric patients at a single institution from 2010 to 2021 was conducted. Platelet count, spleen size and portal vein flow velocity were assessed during the follow-up period. Primary and primary assisted patency time were determined.

RESULTS

A total of ten children (median age 28.5 months, interquartile range (IQR): 2.75-52.5 months) with portal vein stenosis after Mesorex-Shunt (n = 4), liver transplantation (n = 3) and other etiologies (n = 3) underwent 15 interventional procedures. There were five reinterventions and one discontinued intervention. The technical success rate was 93.3% (14/15) and clinical success of treated patients was 100% (14/14). Median follow-up was 18 months (IQR: 13.5-81 months). The median primary patency time for stent placement was 70 months (IQR: 13.5-127.25 months). For balloon angioplasty, the median primary patency time was 9 months (IQR 7.25-11.5 months), while the median assisted primary patency time was 14 months (IQR: 12 to 15 months). Platelet count, spleen size and portal vein flow velocity reliably corresponded to recurrence of portal vein stenosis in asymptomatic patients during follow-up.

CONCLUSION

Interventional treatment is a safe and efficient method to treat portal vein stenosis with long patency times, regardless of etiology. Primary stent placement shows a higher primary patency time than balloon angioplasty. Implementation of stent placement as the primary interventional method may improve patency times and reduce the need for repeat reinterventions in pediatric patients.

Percutaneous transhepatic interventional therapy of portal vein stenosis in paediatric liver transplantation: A systematic review of efficacy and safety

PURPOSE OF THE SYSTEMATIC REVIEW

To determine the efficacy and safety of percutaneous trans-hepatic balloon and/or stent angioplasty (PTA) in the management of portal vein (PV) stenosis following paediatric liver transplantation.

METHODS

Articles were included from a systematic search of Medline, Embase, Cochrane CENTRAL, ClinicalTrials.gov and International Clinical Trials Registry from inception to the 29th of August 2020.

RESULTS

There were 213 paediatric liver recipients who underwent PTA for PV stenosis in 19 included studies published between 1991 and 2019. Balloon angioplasty was the initial treatment in the majority (n = 153). Primary stent placement (n = 34) was performed for elastic recoil, intimal tears and PV kinks and rescue stent placement (n = 14) for recurrent PV stenosis following primary balloon angioplasty. The technical success was 97.6%-100% overall, 97.6%-100% for balloon-angioplasty-only and 100% for primary stenting. The clinical success was 50%-100% overall, 50%-100% for balloon-angioplasty-only and 100% for primary stenting. Long-term PV patency was 50%-100% overall, 37.5%-100% for balloon-angioplasty-only and 100% for primary stenting. Primary balloon angioplasty was successful in 78% of the cases. Of the recurrent PV stenoses, 9% resolved with stent placement and one required a meso-Rex shunt. There was one re-transplantation without stenting. The complication rate was 2.6% for balloon-angioplasty-only (bleeding, liver abscess, 2 PV thromboses) and 5.9% for primary stenting (bleeding, stent-fracture). There was no procedure-related mortality.

CONCLUSION

Percutaneous transhepatic balloon angioplasty may be the initial management of portal vein stenosis in paediatric liver recipients. Stent placement may be a primary option in selected cases and a reliable rescue option for recurrent portal vein stenosis following balloon-angioplasty-only.

The Application of Interventional Radiology in Living-Donor Liver Transplantation

Owing to improvements in surgical techniques and medical care, living-donor liver transplantation has become an established treatment modality in patients with end-stage liver disease. However, various vascular or non-vascular complications may occur during or after transplantation. Herein, we review how interventional radiologic techniques can be used to treat these complications.

Feasibility and mid- to long-term results of endovascular treatment for portal vein thrombosis after living-donor liver transplantation

PURPOSE

We aimed to evaluate mid- to long-term results of endovascular treatment for portal vein thrombosis (PVT) after living-donor liver transplantation (LDLT).

METHODS

Thirty cases (14 males, 16 females; age range, 0.67-65 years) who underwent endovascular treatment including thrombolysis, angioplasty, stent placement, and/or collateral embolization for PVT after LDLT from 2001 to 2017 were retrospectively reviewed. Clinical and procedural data were collected and analyzed regarding the patency of the PVT site at the last follow-up date (PVT-free persistency) using Log-rank test. Results were considered statistically significant at P < 0.05.

RESULTS

Median follow-up was 120 months. The technical success rate was 80% (n=24). Patency rates at 1 week and 1, 3, 6, 12, 36, and 60 months were 73%, 59%, 55%, 51%, 51%, 51%, and 51% for primary patency and 80%, 70%, 66%, 66%, 66%, 61%, and 61% for assisted patency after secondary endovascular treatment. PVT-free persistency rates regarding the subgroups were as follows: children under 12 years vs. adults, 50% vs. 68% (P = 0.42); acute vs. nonacute, 76% vs. 46% (P = 0.10); localized vs. extensive, 90% vs. 50% (P = 0.035); transileocolic approach vs. percutaneous-transhepatic approach, 71% vs. 54% (P = 0.39); and thrombolysis-based treatment vs. non-thrombolysis-based treatment, 71% vs. 44% (P = 0.12), respectively. Among technically successful cases, PVT-free persistency rate was 94% for those with hepatopetal flow in the peripheral portal vein vs. 17% for those without hepatopetal flow (P < 0.001). The only major complication occurring was pleural hemorrhage (n=1). Minor complications (i.e., fever) occurred in 18 patients (60%).

CONCLUSION

In conclusion, mid- to long-term portal patency following endovascular treatment was approximately 50%-60% in PVT patients after LDLT. PVT site patency over three months after the first endovascular treatment, localized PVT, and hepatopetal flow in the peripheral portal vein were identified as key prognostic factors for mid- to long-term portal patency.

Benign Portal Vein Stenosis After Pancreaticoduodenectomy

BACKGROUND

The long-term patency of the portal vein (PV) in patients who survive after pancreaticoduodenectomy (PD) remains unclear. The aim of the present study was to investigate the clinical features and risk factors for benign PV stenosis after PD.

METHODS

We retrospectively analyzed the patients who underwent PD from September 2002 and December 2015 at our institution without intraoperative radiation therapy or concomitant PV resection. The postoperative computed tomography of each patient was evaluated, and PV stenosis was defined as the shortest diameter of the PV being <3 mm. The patients with PV stenosis due to local recurrence were excluded.

RESULTS

Of the 458 patients, PV stenosis occurred in 57 (12.4%), including benign PV stenosis in 28 (6.1%) and PV stenosis due to local recurrence in 29 (6.3%). Of the 28 patients with benign PV stenosis, 7 (25%) developed symptoms related to portal hypertension, namely recurrent gastrointestinal bleeding in 5 and refractory ascites in 2. Six patients were treated with percutaneous transhepatic PV stent placement, and all of their symptoms improved. A multivariate analysis found that a postoperative pancreatic fistula was an independent risk factor for benign PV stenosis after PD (odds ratio, 4.36; p = 0.005).

CONCLUSIONS

Postoperative pancreatic fistula was a significant risk factor for benign PV stenosis after PD. Stent placement for benign PV stenosis was effective for the patients with symptoms due to portal hypertension.

Transition of Spleen Volume Long After Pediatric Living Donor Liver Transplantation for Biliary Atresia

PURPOSE

After undergoing the Kasai procedure for biliary atresia (BA), most patients develop severe splenomegaly that tends to be improved by liver transplantation. However, fluctuations in splenic volume long after transplantation remain to be elucidated.

PATIENTS AND METHODS

Seventy-one consecutive patients who had undergone pediatric living donor liver transplantation (LDLT) for BA were followed up in our outpatient clinic for 5 years. They were classified into 3 groups according to their clinical outcomes: a good course group (GC, n = 41) who were maintained on only 1 or without an immunosuppressant, a liver dysfunction group (LD, n = 18) who were maintained on 2 or 3 types of immunosuppressants, and a vascular complication group (VC, n = 11). Splenic and hepatic volumes were calculated by computed tomography in 464 examinations and the values compared before and after the treatment, especially in the VC group.

RESULTS

Splenic volume decreased exponentially in the GC group, with splenic volume to standard spleen volume ratio (SD) being 1.59 (0.33) 5 years after liver transplantation. Splenic volume to standard spleen volume ratios were greater in the VC and LD groups than in the GC group. Patients in the VC group with portal vein stenosis developed liver atrophy and splenomegaly, whereas those with hepatic vein stenosis developed hepatomegaly and splenomegaly. Interventional radiation therapy tended to improve the associated symptoms.

CONCLUSIONS

Fluctuations in splenic volume long after pediatric LDLT for BA may reflect various clinical conditions. Evaluation of both splenic and hepatic volumes can facilitate understanding clinical conditions following pediatric LDLT.

Interventional Treatment of Severe Portal Vein Thrombosis after Living-Donor Liver Transplantation

Portal vein thrombosis (PVT) is a rare complication of liver transplantation which can lead to graft failure and patient death. Treatment can be difficult, especially in cases of PVT from the intrahepatic portal vein to the proximal jejunal veins. A 55-year-old woman had undergone living-donor liver transplantation with splenectomy for end-stage liver cirrhosis due to hepatitis C with hepatocellular carcinoma. Ten months after transplantation, massive ascites and slight abdominal pain developed, and computed tomography revealed a PVT between the intrahepatic portal vein and the superior mesenteric vein. Repeated interventional radiology procedures were used in combination with thrombolysis, thrombectomy, and metallic stent replacement to obtain favorable portal flow to the graft. Five years after being treated, the patient is well, with favorable portal flow having been confirmed. In conclusion, repeated and assiduous interventional radiological treatment combined with thrombolytic therapy, thrombectomy, and metallic stent replacement could be important for severe PVT.

Jejunal varices diagnosed by capsule endoscopy in patients with post-liver transplant portal hypertension

Portal hypertension secondary to portal vein obstruction following liver transplant occurs in 5%-10% of children. Jejunal varices are uncommon in this group. We present a case series of children with significant GI blood loss, negative upper endoscopy, and jejunal varices detected by CE. Case series of patients who had CE for chronic GI blood loss following liver transplantation. Three patients who had their initial transplants at a median age of 7 months were identified at our institution presenting at a median age of 8 years (range 7-16 years) with a median Hgb of 2.8 g/dL (range 1.8-6.8 g/dL). Upper endoscopy was negative for significant esophageal varices, gastric varices, and bleeding portal gastropathy in all three children. All three patients had significant jejunal varices noted on CE in mid-jejunum. Jejunal varices were described as large prominent bluish vessels underneath visualized mucosa, one with evidence of recent bleeding. The results led to venoplasty of the portal vein in two patients and a decompressive shunt in one patient with resolution of GI bleed and anemia. CE is useful to diagnose intestinal varices in children with portal hypertension and GI bleeding following liver transplant.

Hepatic arterial and portal venous complications after adult and pediatric living donor liver transplantation, risk factors, management and outcome (A retrospective cohort study)

OBJECTIVES

Hepatic arterial (HA) and portal venous (PV) complications of recipients after living donor liver transplantation(LDLT) result in patient loss. The aim of this study was to analyze these complications.

METHODS

We retrospectively analyzed HA and/or PV complications in 213 of 222 recipients underwent LDLT in our centre. The overall male/female and adult/pediatric ratios were 183/30 and 186/27 respectively.

RESULTS

The overall incidence of HA and/or PV complications was 19.7% (n = 42), while adult and pediatric complications were 18.3% (n = 39) and 1.4% (n = 3) respectively. However early (<1month) and late (>1month) complications were 9.4% (n = 20) and 10.3% (n = 22) respectively. Individually HA problems (HA stenosis, HA thrombosis, injury and arterial steal syndrome) 15% (n = 32), PV problems (PV thrombosis and PV stenosis) 2.8% (n = 6) and simultaneous HA and PV problems 1.9% (n = 4). 40/42 of complications were managed by angiography (n = 18), surgery (n = 10) or medically (Anticoagulant and/or thrombolytic) (n = 12) where successful treatment occurred in 18 patients. 13/42 (31%) of patients died as a direct result of these complications. Preoperative PVT was significant predictor of these complications in univariate analysis. The 6-month, 1-, 3-, 5- 7- and 10-year survival rates in patients were 65.3%, 61.5%, 55.9%, 55.4%, 54.5% and 54.5% respectively.

CONCLUSION

HA and/or PV complications specially early ones lead to significant poor outcome after LDLT, so proper dealing with the risk factors like pre LT PVT (I.e. More intensive anticoagulation therapy) and the effective management of these complications are mandatory for improving outcome.

Hepatic arterial and portal venous complications after adult and pediatric living donor liver transplantation, risk factors, management and outcome (A retrospective cohort study)

Objectives

Hepatic arterial (HA) and portal venous (PV) complications of recipients after living donor liver transplantation(LDLT) result in patient loss. The aim of this study was to analyze these complications.

Methods

We retrospectively analyzed HA and/or PV complications in 213 of 222 recipients underwent LDLT in our centre. The overall male/female and adult/pediatric ratios were 183/30 and 186/27 respectively.

Results

The overall incidence of HA and/or PV complications was 19.7% (n = 42), while adult and pediatric complications were 18.3% (n = 39) and 1.4% (n = 3) respectively. However early (<1month) and late (>1month) complications were 9.4% (n = 20) and 10.3% (n = 22) respectively. Individually HA problems (HA stenosis, HA thrombosis, injury and arterial steal syndrome) 15% (n = 32), PV problems (PV thrombosis and PV stenosis) 2.8% (n = 6) and simultaneous HA and PV problems 1.9% (n = 4). 40/42 of complications were managed by angiography (n = 18), surgery (n = 10) or medically (Anticoagulant and/or thrombolytic) (n = 12) where successful treatment occurred in 18 patients. 13/42 (31%) of patients died as a direct result of these complications. Preoperative PVT was significant predictor of these complications in univariate analysis. The 6-month, 1-, 3-, 5- 7- and 10-year survival rates in patients were 65.3%, 61.5%, 55.9%, 55.4%, 54.5% and 54.5% respectively.

Conclusion

HA and/or PV complications specially early ones lead to significant poor outcome after LDLT, so proper dealing with the risk factors like pre LT PVT (I.e. More intensive anticoagulation therapy) and the effective management of these complications are mandatory for improving outcome.

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Preoperative PVT was significant predictor of HA and/or PV complications.

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HA and/or PV complications especially early ones lead to significant poor outcome.

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Proper dealing with the risk factors like pre LT PVT improves outcome.

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The effective management of these complications is mandatory for improving outcome.

Stent Placement for Portal Vein Stenosis After Pancreaticoduodenectomy

BACKGROUND

Portal vein (PV) stenosis is a worrisome late complication following pancreaticoduodenectomy (PD) that causes intestinal bleeding from varices, which must be diagnosed correctly and treated promptly. Recent reports advocate the usefulness of stent placement to improve PV stenosis.

METHODS

We evaluated the cause, diagnosis, and treatment method of PV stenosis after PD and the duration of stent patency in our institution.

RESULTS

Intestinal bleeding caused by PV stenosis occurred in 5 (2.4%) of 205 patients. A computed tomography scan was useful to diagnose this complication. Four of 5 patients with PV stenosis underwent percutaneous transhepatic PV stent placement. The duration of stent patency was 21-41 months, and no rebleeding occurred.

CONCLUSIONS

Percutaneous stent placement is viable, less invasive option than laparotomy for the management of PV stenosis after PD.

Current state of the art in management of vascular complications after pediatric liver transplantation

Vascular complications by compromising the blood flow to the allograft can have significant and sometimes life-threatening consequences after pediatric liver transplantation. High level of suspicion and aggressive utilization of diagnostic modalities can lead to early diagnosis and salvage of the allograft. This review will summarize the current trends in management of vascular complications after pediatric liver transplantation.

Frequency of and factors associated with vascular complications after pediatric liver transplantation

OBJECTIVE

to evaluate the frequency and factors associated with vascular complications after pediatric liver transplantation.

METHOD

risk factors were evaluated in 99 patients under 18 years of age with chronic liver disease who underwent deceased donor liver transplantation (DDLT) between March of 1995 and November of 2009 at the Hospital de Clínicas de Porto Alegre, Brazil. The variables analyzed included donor and recipient age, gender, and weight; indication for transplant; PELD/MELD scores; technical aspects; postoperative vascular complications; and survival.

RESULTS

vascular complications occurred in 19 patients (19%). Arterial events were most common, occurred earlier in the postoperative period, and were associated with high graft loss and mortality rates. In the multivariate analysis, the following factors were identified: portal vein diameter ≤ 3mm, donor-to-recipient body weight ratio (DRWR), prolonged ischemic time, and use of arterial grafts.

CONCLUSION

the choice of treatment depends on the timing of diagnosis; however, in this study, surgical revision or correction produced worse outcomes than percutaneous angioplasty. The reduction of risk factors and early detection of vascular complications are key elements to a successful transplantation.

Management of late-onset portal vein complications in pediatric living-donor liver transplantation

The purpose of this study was to evaluate retrospectively the results of PTA for late-onset PV complications after pediatric LDLT and to assess whether a meso-Rex shunt is a viable option for treating restenosis of the PV after PTA in selected cases. Seventy-five children who underwent adult-to-child LDLT were included in this study, and there were six late-onset PV complications (8.0%). The initial therapeutic approach was PTA, with or without stent: PTA with balloon dilation for three children, PTA with stent placement for one child, and failure to cannulate the occluded PV for two children. A meso-Rex shunt was performed in the two children after failed PTA: One suffered complete obstruction of the main PV, and the other, restenosis with total thrombosis after PTA with stent. The PTA was a technical and clinical success in four with PV stenosis of the six patients (66.7%), and successful application of a meso-Rex shunt in the other two children resulted in restoration of PV flow. In conclusion, PTA is a safe and effective procedure for treating late-onset PV stenosis after pediatric LDLT. However, in growing pediatric recipients with restenosis of the PV after PTA or chronic PV thrombosis, a meso-Rex shunt may be a better choice for late-onset PV complications.

Portal vein stenosis after pancreatectomy following neoadjuvant chemoradiation therapy for pancreatic cancer

Extrahepatic portal vein (PV) stenosis has various causes, such as tumor encasement, pancreatitis and as a post-surgical complication. With regard to post-pancreaticoduodenectomy, intraoperative radiation therapy with/without PV resection is reported to be associated with PV stenosis. However, there has been no report of PV stenosis after pancreatectomy following neoadjuvant chemoradiation therapy (NACRT). Here we report the cases of three patients with PV stenosis after pancreatectomy and PV resection following gemcitabine-based NACRT for pancreatic cancer and their successful treatment with stent placement. We have performed NACRT in 18 patients with borderline resectable pancreatic cancer since 2005. Of the 15 patients who completed NACRT, nine had undergone pancreatectomy. Combined portal resection was performed in eight of the nine patients. We report here three patients with PV stenosis, and thus the ratio of post-operative PV stenosis in patients with PV resection following NACRT is 37.5% in this series. We encountered no case of PV stenosis among 22 patients operated with PV resection for pancreatobiliary cancer without NACRT during the same period. A relationship between PV stenosis and NACRT is suspected, but further investigation is required to determine whether NACRT has relevance to PV stenosis.

Portal vein stenosis: a rare yet clinically important cause of delayed-onset ascites after adult deceased donor liver transplantation: two case reports

Vascular complications following liver transplantation are well documented. While complications involving the portal vein are less common than the hepatic artery, portal vein complications can lead to potentially life-threatening sequelae including graft loss. Portal vein stenosis is an infrequent complication following liver transplant. The majority of these complications are seen in living donor liver transplants and pediatric liver transplants. We present 2 cases of delayed onset portal vein stenosis in adult deceased donor liver transplantation (ADDLT). The first patient presented with refractory ascites twelve months after ADDLT. He was diagnosed and successfully treated with percutaneous transhepatic portovenography and venoplasty. The second patient had a history of irradiation to his portal bed in the setting of cholangiocarcinoma. He developed refractory ascites and esophageal variceal bleeding>2 years after ADDLT. He underwent percutaneous transhepatic portovenoplasty, but eventually required placement of a portal stent due to continued problems with recurrent ascites. These 2 cases highlight the importance of considering portal vein stenosis in the differential diagnosis of late-onset ascites following liver transplantation, especially if there have been any predisposing risk factors such as portal bed irradiation or prior splenectomy.

Intra-operative management of low portal vein flow in pediatric living donor liver transplantation

For pediatric living donor liver transplantation, portal vein complications cause significant morbidity and graft failure. Routine intra-operative Doppler ultrasound is performed after graft reperfusion to evaluate the flow of portal vein. This retrospective study reviewed 65 children who had undergone living donor liver transplantation. Seven patients were detected with suboptimal portal vein flow velocity following vascular reconstruction and abdominal closure. They underwent immediate on-table interventions to improve the portal vein flow. Both surgical and endovascular modalities were employed, namely, graft re-positioning, collateral shunt ligation, thrombectomy, revision of anastomosis, inferior mesenteric vein cannulation, and endovascular stenting. The ultrasonographic follow-up assessment for all seven patients demonstrated patent portal vein and satisfactory flow. We reviewed our experience on the different modalities and proposed an approach for our future intra-operative management to improve portal vein flow at the time of liver transplantation.

Roux-en-Y loop varices in children with portal hypertension after liver transplantation: an unusual cause of "obscure" gastrointestinal bleeding

PHALT may result from graft dysfunction, portal vein thrombosis, arterio-venous fistulas and can lead to GIB, commonly from bleeding esophageal varices. We present three children with GIB requiring multiple blood transfusions that were diagnosed with RY Loop bleeding. Routine EGD, colonoscopy, and CE failed to reveal the bleeding source. However, enteroscopy revealed large varices at the site of hepaticojejunostomy anastomosis in all. Our experience demonstrates that RY loop varices in children with PHALT are a rare and treatable cause of obscure GI bleeding.

Diagnosis and treatment of late-onset portal vein stenosis after pediatric living-donor liver transplantation

PURPOSE

Portal vein stenosis is a relatively rare complication after living-donor liver transplantation, which sometimes leads to a life-threatening event owing to gastrointestinal bleeding or graft failure. This study sought to evaluate the diagnoses and management of late-onset portal vein stenosis in pediatric living-donor liver transplants.

MATERIALS AND METHODS

Since September 2001, we performed 123 living-donor liver transplant procedures in 120 children, among which 109 children with a functioning graft at 6 months after living-donor liver transplant are included in this analysis. Seven instances of portal vein stenosis were diagnosed and were analyzed retrospectively.

RESULTS

The median age of the children was 5.3 years, and the median body weight was 19.2 kg. Portal vein stenosis was diagnosed at 11.2±3.1 months after living-donor liver transplantation. Whereas 3 children were asymptomatic, splenomegaly and/or massive ascites were observed in the remaining 4. Additionally, platelet counts were below the normal limit in 4 children. All children were treated with transhepatic balloon dilatation except 1. Intraluminal stent placement was needed in 1 child owing to resistance of balloon dilatation. The mean pressure gradient decreased from 12.4 to 3.2 mmHg after successful treatment. We did not observe any treatment-related complications. Portal venous patency was maintained in all children during posttreatment follow-up of 43.2±20.4 months. There were no recurrences of portal vein stenosis. One child died; the remaining 6 children are alive with good graft function at 49.8±23.9 months of follow-up.

CONCLUSION

Although most portal vein stenosis is asymptomatic, splenomegaly and platelet counts are 2 important markers for portal vein stenosis. Early detection of portal vein stenosis with these 2 markers can lead to successful interventional percutaneous approaches and avoid graft loss.

Graft rotation and late portal vein complications in pediatric living donor liver transplantation using left-sided grafts: long-term computed tomography observations

Right-side rotation of the graft is an uncommon event after pediatric living donor liver transplantation (LDLT) with a left-sided graft. However, graft rotation might lead to gradual portal vein (PV) stretching and late portal vein complications (PVCs). The goal of this study was to quantify the degree of graft rotation (R) by computed tomography (CT) and to determine the effect of graft rotation on the development of late PVCs. One hundred ten patients underwent LDLT with left-sided grafts between 1996 and 2009; CT images were available and were reviewed for 66 of these patients. To quantify R, the following variables were measured with CT: the longest distance between the midline and the extrahepatic PV at the level of the hepatic hilum (A), the distance between the midline and the center of the superior mesenteric vein at the level of the confluence of the splenic vein and superior mesenteric vein (B), and the inner transverse diameter of the body cavity at the level at which A was measured (C). R was calculated as (A - B)/C. In patients with a patent PV (n = 59) and in patients with late PVCs (n = 7), the median R values were 0.16 (range = 0.03-0.38) and 0.25 (range = 0.13-0.39), respectively; there was a significant difference between the 2 groups (P = 0.003). Multivariate analysis showed that R ≥ 0.2 was the only independent risk factor for the development of late PVCs (P = 0.021). In conclusion, the gradual stretching of the PV after right-side rotation of left-sided grafts might play an important role in the development of late PVCs. PV patency should be closely monitored when graft rotation is noted during clinical follow-up.

ADP-dependent platelet function prior to and in the early course of pediatric liver transplantation and persisting thrombocytopenia are positively correlated with ischemia/reperfusion injury

Little is known about the role of platelets in relation to ischemia/reperfusion injury (IRI) of the liver graft especially in children. Thrombocyte function was prospectively analysed in 21 consecutive pediatric liver transplantation (pLT) patients by platelet aggregometry secondary to adenosine diphosphate (ADP), collagen, and the von Willebrand factor activator ristocetin (VWF:rco). Post-OP serum levels of ALT were used to divide patients into groups with high (highHD, n = 8) and low (lowHD, n = 13) hepatocellular damage. Clinically, highHD-patients showed impaired plasmatic coagulation and elevated serum bilirubin levels early after pLT when compared with lowHD-patients. Further, platelet counts markedly decreased between pre-OP and postreperfusion (postrep.) in the highHD group (P = 0.003) and did not recuperate by POD6. In lowHD individuals thrombocytopenia improved from both pre-OP (P < 0.05) and postrep. (P < 0.001) respectively towards POD6. Experimental thrombocyte testing revealed that before graft reperfusion only ADP-dependent platelet aggregation correlated with reperfusion injury, thrombocytopenia and early graft function. During the first 48 h after graft reperfusion, all inducers tested demonstrated elevated platelet aggregation levels in the highHD group. Our data suggest a possible role of platelets and their aggregative status in liver IRI subsequent to clinical pLT. Reperfusion-independent ADP-triggered platelet function may be a determinant for IRI in the pediatric hepatic graft recipient.