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while pancreatic resection is the only effective treatment with prolonged survival in operable pancreatic cancer and peri - ampullary cancer , it is also a procedure of significant morbidity and complications .
the most commonly reported postoperative complications after pancreatic resection are pancreatic fistula , delayed gastric emptying , intra - abdominal sepsis and postoperative hemorrhage .
many vessels are encountered during pancreatic resection in particular pancreaticoduodenectomy ( pd ) , especially superior mesenteric and portal veins , superior mesenteric and hepatic arteries , and celiac trunk .
hepatic artery is usually the only arterial supply of the liver , any injury of common hepatic artery ( cha ) carries the hazard of deprivation of the liver of arterial blood which may lead to acute liver failure , sepsis or liver abscess , and biliary complications in form of stricture or leak at site of anastomosis or bile duct vanishing syndrome in the most devastating scenario , .
we describe a case of 70-year - old male , with eight weeks history of jaundice and repeated vomiting . no other relevant history was available .
the significantly altered lab parameters showed a total serum bilirubin 5.7  mg / dl , direct of 4.7  mg / dl , inr 1.2 , with normal alt , ast , serum electrolyte and serum creatinine .
an ultrasound of abdomen was done which showed mild hepatomegaly with dilated intra and extra hepatic biliary channels , no features of cirrhosis of liver or portal hypertension and identified a hypo - echoic lesion in the head of pancreas . based on these data we ordered contrast enhanced computed tomography ( cect ) scan for the abdomen , which revealed soft tissue mass arising from head of pancreas with 3    5  cm size with slight haziness of fat planes between it and stomach , superior mesenteric artery , portal and superior mesenteric vein
are free from any invasion , with mildly dilated stomach with enlarged supra - pancreatic and peri - portal lymph nodes 2    3  cm with no distant metastasis .
patient was diagnosed as cancer head of pancreas with possibility of gastric wall invasion and decision was taken for surgical intervention and preoperative plan was for pancreaticodudenctomy .
he was evaluated by cardiac , pulmonary and anesthesia physician and was found fit for surgery .
during dissection of supra - pancreatic lymph nodes , common hepatic artery was accidentally injured and repair with proline 8/0 using surgical loups 3.5 was done .
intraoperative doppler on hepatic artery shows normal flow with ri 0.6 and psv 100  cm / s pre anastomotic and 125  cm / s post anastomotic and sat 71  ms .
postoperative day ( pod ) one , patient was stable , but doppler on hepatic artery revealed no detectable flow .
( normal range ; alt  < 41  u / l , ast  <  38 
u / l ) cect was done and revealed completely thrombosed common hepatic artery with no detected contrast beyond site of repair .
interestingly intrahepatic small accessory left hepatic artery with hardly detectable middle hepatic artery was found which followed to be arised from left gastric artery ( fig .
1 ) . decision was taken to follow the patient for few days to detect the trend of laboratory findings .
surprisingly alt , ast , and bilirubin start to decrease significantly from pod2 with gradual improvement of all liver function parameters .
patient was shifted from icu to word on pod3 ; another doppler on hepatic artery did not detect any flow in the hepatic artery after the site of repair . on pod 10 ,
u / l ; ast 34  u / l and total bilirubin was 1.3  mg / dl ( fig .
follow up two weeks later in out patient clinic revealed normalization of liver function tests with non - detectable hepatic artery flow by liver doppler and no relevant significant complaint .
follow up six months later revealed normal lab parameters , cect scan was done again and revealed completely thrombosed hepatic artery with small accessory left hepatic artery with hardly detectable middle hepatic artery ( fig .
hepatic artery thrombosis following pd in not a commonly encountered complication . although thrombosis of common hepatic artery may pass without significant morbidity due to compensatory flow of arterial blood to the hepatic artery proper through gastrodudenal artery ( gda ) , but this is not the situation in pd as gda is ligated as a step of the procedure , keeping the hazards any thrombosis of cha will lead to complete deprivation of the liver from its arterial blood supply .
the typical course of such a situation is hepatic infarction followed by acute liver failure and septicemia .
impairment of hepatic blood supply was termed as ischemic hepatitis ( ih ) which indicates inadequate hepatic perfusion , one of the possible causes of ischemic hepatitis is common hepatic artery thrombosis , it is characterized by significant rise in liver enzymes and bilirubin with undetectable doppler signals on common hepatic artery , cect is a confirmatory imaging modality is such a situation showing hypo perfusion of the liver , abrupt of the contrast at site of obstruction and hypo dense filling defect in the arterial lumen .
clinical presentations of ih ranges from devastating course which is fulminant acute liver failure due to ischemic hepatic necrosis and bile duct vanishing syndrome to less catastrophic courses as biliary stricture or liver abscess .
all these undesirable sequel encourage early intervention and trial to revascularize the obstructed cha to avoid these morbidities , , . here in our case
we noticed small intra hepatic arterial vessels in spite of absence of any contrast in hepatic artery in cect scan with apparent thrombus at site of repair . a hardly detectable small accessory left hepatic artery with middle hepatic artery mostly arised from left gastric artery are noticed .
also faint hepatic contrast was noticed in the arterial phase in cect , this encourage our team to take the decision of not to operate the patient again to re - vascularize the artery as we believed , these small vessels were sufficient to give enhancement to the liver so they may be sufficient to supply the liver itself .
surprisingly liver enzymes and liver functions improve significantly starting from pod 2 which supported our believe regarding sufficiency of these small vessels to give arterial blood supply to the liver , six months later follow up cect scan showed a completely thrombosed cha with no detected liver infarction , abscess or biliary complications .
although hepatic artery is the only arterial supply of the liver , occasionally small accessory arteries may give significant arterial blood supply , which may compensate any blockage or thrombosis of hepatic artery , especially after ligation of gda as in pd .
in such a situation liver enzymes and liver enhancement in cect scan act as surrogate markers to assess the sufficiency of this flow to the liver .
ramy hassan and ahmed zidan were involved in writing manuscript . ahmed taha and bashir fadel were involved in patient management , and tameem ibraheem revise and approve manuscript for submission .
highlightspancreatic resection is the only effective treatment with prolonged survival in operable pancreatic cancer and peri - ampullary cancer.we report here a case of common hepatic artery injury during pancreaticodudenectomy followed by complete thrombosis after its repair.surprisingly liver enzymes and bilirubin start to improve in post operatively due to small hardly detected accessory left and middle hepatic artery .