Meso-Rex shunt for immediate portal revascularization in pediatric liver transplantation: first report

We describe the case of a 13-month-old girl transplanted for biliary atresia with PV hypoplasia. She received the left liver lobe of her mother and presented intraoperative portal thrombosis. Because of technical reasons, the opportunity to have conventional PV reconstruction using the donor left PV stump was lost. Immediate conversion to a meso-Rex shunt, using the recipient jugular vein as a bridge between the superior mesenteric vein and the graft Rex recessus, allowed excellent portal revascularization of the transplant. We suggest that synchronous meso-Rex shunt may constitute a valid alternative to truncal PV anastomosis during pediatric LT.     

Portal vein reconstruction using vein grafts in pediatric living donor liver transplantation: Current status

PV reconstruction is an important aspect of LDLT, with post‐transplant outcomes depending on PV reconstruction methods. However, it is unclear whether the preferential selection of these techniques is dependent on preoperative recipient characteristics. This retrospective study assessed whether preoperative recipient factors differed in pediatric patients who did and did not receive VGs for PV reconstruction. Of 113 pediatric patients who underwent LDLT from January 2010 to July 2015, 31 (27%) underwent PV reconstruction with VGs and the other 82 (73%) without VGs. The presence of collateral vessels (P<.0001) and ascites (P=.02); PV size (P<.001), thrombosis (P=.01) and the direction of flow (P=.01), Child‐Pugh class A vs B/C liver function (P=.01), Alb concentration (P=.02), primary diagnosis: BA vs non‐BA (P=.03), and previous abdominal surgery (P<.005) differed significantly in patients who did and did not receive VGs for PV reconstruction. PV complications, patient survival, and graft survival did not differ significantly in patients with and without VGs at 1‐year follow‐up. VGs should be harvested for recipients with pretransplant hypoplastic PV, intense collaterals, hepatofugal flow, poor liver status, or previous abdominal surgery.     

A central approach to splenorenal shunt in pediatric living donor liver transplantation

The management of LSRS is a crucial problem to ensure a sufficient PV flow during pediatric LT. Although several techniques have been indicated to solve this problem, a more appropriate approach to LSRS is still needed in pediatric LT. We herein present a modified surgical approach to the ligation of LSRS via the left side of the IVC for a nine‐month‐old boy with severe portal hypertension and a history of Kasai portoenterostomy. LSRS was identified and exposed through the left side of the IVC and the dorsal surface of the pancreas from the superior side of the body of the pancreas. The post‐operative course was uneventful with an excellent PV flow. The central approach for the ligation of LSRS is worth considering as an alternative procedure for a patient with collateral vessels and a history of multiple laparotomies.     

Survival among children with portal vein thrombosis and end-stage liver disease

Al-Holou S, Mathur AK, Ranney D, Kubus J, Englesbe MJ. Survival among children with portal vein thrombosis and end-stage liver disease.
Pediatr Transplantation 2010: 14: 132–137. © 2009 John Wiley & Sons A/S.
Abstract:  Occlusive PVT concurrent with chronic liver disease is a common clinical entity among pediatric patients referred for transplantation. The natural history of PVT is unknown. Our aim was to determine, using a retrospective cohort design, if children under 13 yr with chronic liver disease and concomitant PVT have an increased mortality risk prior to and after transplantation. A total of 203 patients were included in the study. Nearly 10% of the population had PVT (n = 19); 63.2% of PVT patients (5.9% of total cohort) underwent liver transplantation (n = 12). PVT patients tended to be younger than non-PVT patients at evaluation (1.94 ± 3.51 vs. 3.79 ± 4.11, p = 0.059). Clinical and demographic factors were similar between the two groups. Regarding survival, four PVT patients died, of which two had undergone transplantation. Kaplan–Meier analyses indicated that PVT and non-PVT patients had similar survival from the time of evaluation, on the waiting list, and after transplant. Although limited by sample size, our study suggests that a diagnosis of PVT does not increase the mortality risk for children waiting for a liver transplant. Further study is needed to discern variations in mortality risk that may occur in the pediatric chronic liver disease population with PVT.     

Intra‐operative portal hemodynamics in pediatric LDLT: Doppler ultrasound surveillance

Doppler ultrasonography is useful in monitoring intra‐operative PV flow in LDLT. A retrospective cohort study included 550 pediatric recipients (<18 years) who underwent LDLT from October 2006 to August 2016 in our hospital. A total of 33 recipients (incidence 6%) were found to have insufficient intra‐operative PV flow after PV reperfusion. The treatments included intra‐operative stent placement (n=25), anticoagulation (n=3), thrombectomy and re‐anastomosis (n=2), graft repositioning (n=1), collateral ligation (n=1), and replaced PV (n=1). The peak PV velocity, HAPSV, HARI, and HV velocity before and after the interventions were significantly improved 0(0,5.5) cm/s vs. 37.36±15.30 cm/s, 38.68±8.92 cm/s vs. 62.30±16.97 cm/s, 0.55±0.08 vs. 0.76±0.10, and 32.37±10.33 cm/s vs. 40.94±15.01 cm/s, respectively (P<.01). Insufficient PV flow and decreased HARI are two significant criteria indicating need for intra‐operative PV management. Dramatic changes in the hepatic hemodynamics were detected after proper treatment. Immediate resolution of PV flow is feasible in pediatric LDLT.     

Recanalization of post‐transplant late‐onset long segmental portal vein thrombosis with bidirectional transhepatic and transmesenteric approach

PV complications are the most frequent vascular complications in pediatric LT. We have experienced a case with chronic postoperative PVT that necessitates combined transhepatic and transmesenteric approach and have confirmed mid‐term patency. An eight‐yr‐old boy had successful LDLT with a left lateral segment graft at the age of two months for HBV‐related acute liver failure. Seven years after transplantation, the patient suddenly showed a melena with hypovolemic shock. Doppler ultrasound and CT revealed intrahepatic bile duct dilatation and main PVT with collateral formation at hepatic hilus and mesenterium of the Roux‐en‐Y jejunal loop. Urgent splenic artery embolization was performed to control the bleeding and was temporarily effective. Therefore, recanalization of PVO was attempted. Because of long segmental PVO and steep angle between the intrahepatic PV and the portal trunk, bidirectional transhepatic and transmesenteric approach was selected and resulted in deploying three metallic stents necessitating additional infusion thrombolytic therapy. The patient is now followed as an outpatient with patent stents for two yr since the procedure. For the rescue of these patients, recanalization of obstructed PV trunk with bidirectional approach would be feasible with better graft survival and less invasiveness than conventional surgical interventions.     

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.     

Decreased portal vein flow during Kawasaki disease in a liver transplant patient

Abnormalities of liver function tests are frequently documented in patients with Kawasaki disease, but the mechanism responsible for this has not yet been established. Described herein is the case of a 1‐year‐10‐month‐old girl who underwent liver transplantation at 11 months of age. Eleven months after transplantation the patient was diagnosed with Kawasaki disease, which was associated with some portal flow reduction, and received i.v. immunoglobulin, after which fever abated with improvement of portal flow to its pre‐fever level. Abnormalities of liver function tests in Kawasaki disease patients may occur as a result of inflammation of both the biliary and portal systems. There are no reports on the potential relationship between Kawasaki disease and the portal vein, and accumulation of further data is necessary to better examine this relationship.     

Unusual shunt for symptomatic portal vein thrombosis after liver transplantation - Clatworthy revisited

PV thrombosis is not an uncommon occurrence following pediatric LT. Symptomatic PHT following PV thrombosis is treated medically, surgical portosystemic shunting (mesorex, splenorenal, and mesocaval) being reserved for refractory cases. A 10-yr-old boy suffered recurrent malena and hemorrhagic shock because of chronic PV thrombosis following LT nine yr ago (1999). Extensive work-up failed to localize the bleeding source. The liver function remained normal. Initial attempts at surgical shunts failed owing to thrombosis (mesocaval 2001, splenorenal, inferior mesenteric-left renal vein, splenic-left external iliac vein 2008). In this situation, we performed a Clatworthy shunt by anastomosing the divided lower end of the LCIV to the side of SMV. There was a single, large caliber anastomosis. Post-operatively, the malena stopped completely, and clinically, there was no lower limb edema or encephalopathy. Doppler USG revealed persistence of hepatopetal flow within the portal collaterals. Follow-up at two yr reveals stable hepatic function with a patent shunt. To the best of our knowledge, we are not aware of a Clatworthy shunt being performed in a transplant setting. We reviewed the literature pertaining to this shunt in non-transplant patients with PHT.     

Incidence,impact, and treatment of portal and hepatic venous complications following pediatric liver transplantation: A single‐center 12 year experience

Heffron TG, Pillen T, Smallwood G, Henry S, Sekar S, Casper K, Solis D, Tang W, Fasola C, Romero R. Incidence, impact, and treatment of portal and hepatic venous complications following pediatric liver transplantation: A single‐center 12 year experience.
Pediatr Transplantation 2010: 14:722–729. © 2010 John Wiley & Sons A/S. Abstract: PVT or PVS and HVOO are known causes of graft and patient loss after pediatric liver transplantation. Increased incidences of these complications have been reported in partial livers including DDSLT or LDLT. From 1997 to 2008, 241 consecutive pediatric patients received 271 hepatic grafts at a single center. Median follow‐up is 1856 days. Surgical technique, demographics, lab values, and radiologic imaging procedures were obtained utilizing OTTR^® to evaluate the relationship of portal and hepatic complications with risk factors, patient and graft survival. Grafts were composed of 115/271 (42.4%) partial livers of which 90 (33.2%) were DDSLT and 25 (9.2%) LDLT. Of 271 patients, 156 (57.6%) received whole‐sized grafts. There were six PVC in five patients with one patient requiring retransplantation (0.34%) and no patient deaths. Utilizing all three hepatic vein orifices on the recipient hepatic vena cava and the donor hepatic vein cut short enables a wide hepatic outflow tract unlikely to twist. None of the 241 patients developed early or late complications of the hepatic vein. None of the last 128 consecutive patients who received 144 grafts over seven and a half yr have developed either early or late complications of the hepatic or portal vein. Partial‐graft actuarial survival was similar to whole‐graft survival (87.2% vs. 85.3% at one yr; 76.6% vs. 80.2 at three yr; p = 0.488). Likewise, patient survival was similar between partial grafts and whole grafts (93.8% vs. 93.1% at one yr; 89.8% vs. 87.2% at three yr; p = 0.688) with median follow‐up of 1822 (±1334) days. Patients receiving partial livers were significantly younger and smaller than patients receiving whole livers (p < 0.001). Portal and hepatic venous complications may have negative effects on patient or graft survival after pediatric liver transplantation. In our series, there was one graft and no patient loss related to portal or hepatic venous complications after pediatric liver transplantation over 12 yr.     

Portal vein pressure and flow modulation in pediatric liver transplantation

Liver transplantation (LT) has been indicated for smaller and more clinically severe patients in recent years. Small biliary atresia (BA) patients often show portal hypoplasia and sclerotic portal vein (PV), which may make PV reconstruction more difficult during the operation. Among PV complications, intraoperative PV thrombosis can be considered a disaster, and it is important to prevent this catastrophic event by the precise assessment of the PV structure and PVF using radiological imaging before and during LT. However, there are no objective parameters to indicate whether sufficient PVF can be obtained. PV pressure (PVP) and PV flow (PVF) have mainly been studied in adult living donor LT, for the purpose of preventing small-for-size syndrome, and PVP has been considered an objective parameter of graft inflow modulation (GIM). In the setting of pediatric LT, GIM is mainly performed to prevent hypoperfusion, and it must be performed before graft implantation. GIM to maximize the PVF of pediatric patients with potentially low PVF in LT consists of the interruption of collateral vessels, the assessment of the usability of the native PV, and technical modifications in PV reconstruction. Reliable objective parameters that represent sufficient PVF before graft implantation are desired. Our recent study proposed that a PVP of ≥25 mmHg before graft implantation can be considered an objective parameter to obtain sufficient PVF (cutoff value: 50 mL/min/100 g of graft weight). Further investigation is needed to determine the best strategy for successful PV reconstruction in pediatric LT.     

A case of pediatric live‐donor liver transplantation with a left lateral segment reduction by a linear stapler after reperfusion

In pediatric LDLT, graft reduction is sometimes required because of the graft size mismatch. Dividing the portal triad and hepatic veins with a linear stapler is a rapid and safe method of reduction. We herein present a case with a left lateral segment reduction achieved using a linear stapler after reperfusion in pediatric LDLT. The patient was a male who had previously undergone Kasai procedure for biliary atresia. We performed the LDLT with his father's lateral segment. According to the pre‐operative volumetry, the GV/SLV ratio was 102.5%. As the patient's PV was narrow, sclerotic and thick, we decided to put an interposition with the IMV graft of the donor between the confluence and the graft PV. The graft PV was anastomosed to the IMV graft. The warm ischemic time was 34 min, and the cold ischemic time was 82 min. The ratio of the graft size to the recipient weight (G/R ratio) was 4.2%. After reperfusion, we found that the graft had poor perfusion and decided to reduce the graft size. We noted good perfusion in the residual area after the lateral edge was clamped with an intestinal clamp. The liver tissue was sufficiently fractured with an intestinal clamp and then was divided with a linear stapler. The final G/R ratio was 3.6%. The total length of the operation was 12 h and 20 min. The amount of blood lost was 430 mL. No surgical complications, including post‐operative hemorrhage and bile leakage, were encountered. We believe that using the linear stapler decreased the duration of the operation and was an acceptable technique for reducing the graft after reperfusion.     

Biliary reconstruction before clamp removal to avoid portal vein thrombosis in pediatric living‐donor liver transplantation using hyper‐reduced left lateral segment grafts: A novel technical strategy

LT has become the treatment of choice for children with end‐stage liver disease. The scarcity of donors and the considerable mortality on waiting lists have propelled the related living‐donor techniques, especially in small children. This population need smaller and good quality grafts and are usually candidates to receive a LLS from a related donor. Many times this grafts are still large and do not fit in the receptor's abdomen, so a further hyper‐reduction may be required. Despite all advances in LT field, vascular complications still occur in a considerable proportion remaining as a significant cause of morbidity, graft loss, and mortality. Technical issues currently play an essential role in its genesis. The widely spread technique for biliary and vascular reconstruction in living donor LT (LDLT) nowadays implies removal of the portal vein (PV) clamp after the venous anastomosis, then the arterial reconstruction is done, followed by the biliary reconstruction. However, due to the posterior location of the LLS bile duct, for its reconstruction, a rotation of the liver is required risking a potential transient PV occlusion leading to thrombosis afterward. We describe a new technique that involves performing biliary reconstruction after the PV anastomosis and before removing the vascular clamp, thus allowing to freely rotate the liver with less risk of PV occlusion and thrombosis.     

Diaphragmatic hernias after pediatric liver transplantation: Experience of a high‐volume transplant center

Diaphragmatic hernias (DHs) are rare complications after pediatric liver transplantation (PLT). It is now widely accepted that DHs after liver transplantation (LT) is a pediatric related condition. PLTs (under of age 18) performed between January 2013 and June 2019 at Malatya Inonu University Institute of Liver Transplantation were retrospectively scanned. Study group consisting DHs and a control group were compared. Among 280 PLTs, 8 of them were complicated with DHs (%2.9). Median age of the patients with DH was 3.0 (0.8‐9.5) years. Median graft recipient weight ratio was 2.5 (0.9‐4.4). Five patients were below 5th percentiles in terms of pediatric weight growth chart at the time of LT. Also, 6 patients were below 5th percentiles in terms of pediatric height growth chart. There was no statistical difference between study and control groups. There are many risk factors mentioned in literature that may be primarily responsible for DHs after PLT. These factors are left lobe and large‐for‐size grafts, malnutrition, trauma or diathermy of diaphragmatic nerve and vessels and immunosuppressants. In our study, we could not specify any reason that differs in DHs. In our aspect, narrow diaphragma and thorax are exposed to high intra‐abdominal pressure from abdomen. Large‐for‐size grafts, which are specific to children, also may contribute to this affect. Excessive diathermy and trauma to diaphragmatic collaterals may aggravate the risk of DH. More patients are needed to make an exact conclusion, in order to evaluate with comparable study on this aspect.     

Abnormal continuation of umbilical vein into extra‐hepatic portal vein: Report of three cases

Anomalies of the umbilical venous system are perplexing essentially due to dissection errors and vascular connection delineation failure. Continuation of umbilical vein into the extra‐hepatic portal vein is classified as group IV umbilical vein anomaly and involves the vitelline vein or its remnants. Despite this categorization most examiners ascribe fetal extra hepatic abdominal vascular abnormality as an umbilical vein anomaly. Since these anomalies involve vitelline vein, the term “umbilical vein anomaly” is inappropriate and should be referred to as “vitelline vein abnormalities”. Vitelline vein abnormalities are exceedingly rare and to the best of our knowledge only three cases have been reported prenatally. We report three cases presenting with intrauterine fetal demise and on perinatal autopsy demonstrating aneurysmally dilated group IV umbilical vein anomaly. Review of the literature, embryological basis and clinical implications of persistent vitelline vein and its varix are discussed.     

A bidirectional approach for portal vein stent placement in a child with complete portal vein occlusion after living donor liver transplantation

Delayed PV complications are not rare in pediatric liver transplantation. Although PTPV offers a treatment and minimizes surgical revision, in case of complete PV thrombosis (PVT), the failure rate of PTPV is high. Herein, we report a successful technique of PTPV in a case of complete PVT with a stent placement using a bidirectional approach in a child with living donor liver transplantation.     

Living donor liver transplantation with alternative porto‐left gastric vein anastomosis in patients with post‐Kasai extrahepatic portal vein obstruction

EPVO is a common cause of prehepatic portal hypertension in pediatric patients and sometimes results in cavernous transformation of the PV. We herein present the cases of two patients who underwent LDLT for EPVO with post‐Kasai biliary atresia. PV reconstruction was performed with a porto‐left gastric vein anastomosis. The patient who underwent PV reconstruction using an interposition vein graft is doing well without surgical complications, whereas PV anastomotic stenosis was detected three months after LDLT in the patient who did not receive an interposition vein graft. The availability of vein grafts is limited in the LDLT setting. In such cases, performing PV reconstruction with varicose veins using interposition vein grafts is a feasible and valuable alternative option for obtaining a sufficient portal blood flow. Our experiences suggest that using interposition vein grafts may be appropriate for preventing the anastomotic stenosis caused by the fragility of varicose veins.     

Evaluation of cardiac manifestations in pediatric liver transplant candidates

Knowledge concerning the involvement of the cardiovascular system in children awaiting liver transplant is limited. Therefore, no guidelines have been established on evaluating this group of patients for cardiac disease. This review examines the diverse cardiovascular manifestations of liver disease in children. We also discuss the available testing and its applicability in screening for cardiac disease in this vulnerable population.     

Long-term follow-up in adult living donors for combined liver/bowel transplant in pediatric recipients: a single center experience

Pediatric candidates for combined liver/bowel transplant (LBTx) experience a very high mortality on the cadaver waiting list. Our transplant center has successfully used adult living donors to treat pediatric candidates for LBTx. We report the long-term follow-up of this unique cohort of organ donors. The charts of six adult donors for LBTx performed between 2004 and 2007 were reviewed. All the pertinent clinical data were carefully reviewed and integrated with phone interviews of all donors. A total of six children (average age 13.5 months) received living donor LBTx. Average follow-up for the donors was 42 months (range 29-51). The donors' median age was 25 yr (19-32); five women and one man. The average median hospital stay was nine days. There were no peri-operative complications. At present all donors remain in good health. Three of the five mothers became pregnant after donation. Five of the six children are currently alive and well whereas one died with functioning grafts six months post-transplant due to plasmoblastic lymphoma. Living donor LBTx is an effective therapy for combined hepatic and intestinal failure in children less than five yr. The donor operation can be performed with minimal morbidity.