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vascular complications after liver transplantation represent a diagnostic challenge and a serious source of morbidities and mortality . the early hepatic venous outflow obstruction ( hvoo )
is a rare but serious complication causing acute budd  chiari syndrome , which may result in graft loss .
early hvoo is mostly caused by technical problems as tight anastomosis , twisting of hepatic veins , intimal flaps , and malpositioning of the graft .
the keypoint in management of this form of obstruction is the early diagnosis which allows proper treatment to prevent graft dysfunction or graft loss .
we report a case of early hvoo after living donor liver transplantation using right hemi - liver graft , which was managed by ectopic placement of foley catheter to maintain adequate outflow of the graft .
a 51 years old male patient with end stage liver disease due to chronic hepatitis c virus infection received a right hemi - liver graft from his brother . prior to transplantation
, the donor was evaluated by hepatic angiography ; to outline the anatomy of the portal vein , hepatic artery and hepatic veins , magnetic resonance cholangio - pancreatography ; to assess of the anatomy of the biliary system , and liver volumetry . in this case , the donor had single hepatic artery , portal vein , and right hepatic vein and single large tributary from segment viii to the middle hepatic vein ( mhv ) .
the liver graft weight was 900  g , and the graft to recipient weight ratio was 0.8% . during back table preparation of the graft
, we routinely reconstructed the tributaries of the mhv of more than 5  mm in diameter or draining significant liver volume depending on preoperative computed tomography and intraoperative ultrasound .
the decision whether to reconstruct or occlude the vein was taken during the recipient surgery depending on the presence of significant graft congestion , the rate of flow in the graft , and occurrence of hemorrhage from the resection surface of the graft after graft reperfusion .
right hepatic vein reconstruction was done by end - to - side anastomosis between donor right hepatic vein and inferior vena cava ( ivc ) using continuous 4/0 polypropylene suture with venoplasty .
drainage of segment viii vein was done to side of ivc using a gortex graft by continuous 4/0 polypropylene suture .
no severe graft congestion or massive bleeding from the transection surface noted at the time of reperfusion .
doppler ultrasound ( us ) examination was done after completion of vascular anastomoses and at the end of operation which confirmed patency of all vascular anastomoses . on the first postoperative day , the patient developed impairment of the liver functions ( total serum bilirubin 8.8  mg / dl , serum aspartate aminotransferase ( ast ) 298  iu / ml , serum alanine aminotransferase ( alt ) 223  iu / ml , and serum gamma glutamyl transferase 32 
doppler us confirmed absence of blood flow in the right hepatic vein without thrombosis ( fig .
, this condition was attributed to torsion of the graft upward and to the right side causing kink of the right hepatic vein because of size difference between the graft and the abdominal space .
the management was performed with a foley catheter , inflated by 50  cc normal saline , placed between the graft and the diaphragm and the chest wall .
gradual deflation of the catheter was started one week after insertion , and was gradually applied for another week guided by doppler us to check adequate hepatic venous outflow ( figs . 2 and 3 ) .
improvement of liver functions was noticed after the exploration ( total serum bilirubin 3.1  mg / dl , serum ast 140  iu / ml , serum alt 155  iu / ml , and serum gamma glutamyl transferase 20  iu / l ) .
doppler us was performed daily in the first postoperative week , and every other day in the second postoperative week to evaluate patency of vascular anastomoses .
hvoo is classified into early ( acute ) and late ( chronic ) types according to its onset after operation .
early hvoo is related to technical problems as tight anastomosis , hepatic veins twisting , and graft malpositioning .
late hvoo or anastomotic stenosis occurs as a result of intimal hyperplasia and perianastomotic fibrosis .
early hvoo after orthotopic liver transplantation is relatively rare with an incidence of less than 2% after the classic technique   and 34% after the piggyback technique .
piggyback technique allows greater mobility of the graft along both antero  posterior and latero - lateral directions .
the incidence increases to 513% in living donor liver transplantation and pediatric split liver transplantation due to greater range of mobility of smaller grafts [ 810 ] . in our experience ,
this low incidence can be explained by that our surgical team had a long experience of shunt operations in management of portal hypertension . in our center , we had performed more than 1000 cases in the era of shunt operations .
mechanical venous outflow obstruction occurs as a result of anatomical mismatch between the liver graft and the recipient abdomen .
it may result from the presence of deep and wide subphrenic space with a relatively small sized graft offering a wider range of movement of the graft and allowing kinking of the venous anastomosis .
also , it may result from compression of venous anastomosis by very large graft after abdominal wall closure .
clinically , early hvoo presents manifestations of hypovolemic shock due to decreased systemic venous return .
the patient developed hypotension that was not explained and did not respond to fluid resuscitation .
early diagnosis of hvoo after liver transplantation is the key point to allow immediate intervention and prevent graft dysfunction or even graft loss .
however , others recommend percutaneous interventions as balloon angioplasty or stent placement as surgical interventions are dangerous and followed by unfavorable outcomes .
we believe that , balloon angioplasty and stent placement is very dangerous during the very early postoperative period for fear of disruption of the newly formed anastomosis .
so in our case , we did not offer such modality and preferred surgical exploration during the early post - transplant period .
mechanical venous outflow obstruction from kinking or twisting of the venous anastomosis should be managed surgically by repositioning of the graft or redo of venous anastomosis or retransplantation .
the use of additional cavo - caval anastomosis or retransplantation is dangerous and associated with a high mortality rate .
several ideas had been suggested for repositioning and fixation of the graft to overcome the venous outflow obstruction .
malassagne et al . and steinbrck et al . used sengstaken  blakemore tube to support the graft and correct venous obstruction .
reported , the use of tissue expander and foley catheter in 7 patients to improve venous obstruction .
others used fixation of the round ligament and placement of small bowel loops to fix the graft in position .
we report the use of foley catheter to temporary fix the graft in position and correct the venous outflow obstruction .
it can be easily monitored and removed under doppler us without any device related complications .
conception and design of the study : wahab m.a . collection and assembly of the data : shehta a. , hamed h. data analysis and interpretation : wahab m.a . ,
we obtained a written informed consent from the patient for the publication of this case report and accompanying images .
a copy of this written consent is available for review by the editor - in - chief of the international journal of surgery case reports on request .
mohamed abdel wahab : professor of surgery , college of medicine , mansoura university , chair of liver transplantation unit , gastroenterology surgical centre , college of medicine , mansoura university , egypt .
ahmed shehta : assistant lecturer of surgery , gastroenterology surgical centre , college of medicine , mansoura university , egypt .
highlightshepatic venous outflow obstruction is a rare serious complication after liver transplantation.hepatic venous outflow obstruction may result in graft loss and recipient death.we report the use of the foley catheter to temporary fix the graft and correct the hepatic venous outflow obstruction.it is a simple , cheap and safe device to correct the hepatic venous outflow obstruction.it could be easily monitored and removed under doppler us without any device related complications .