The preferred bypass procedure in case of nonresctable carcinoma of head of pancreas is

Palliative surgery in Advanced, Non-resectable pancreatic Association Surgery for advanced, non resectable pancreatic adenocarcinoma can palliate obstruction of CBD or duodenum, as well as control visceral pain Hepaticojejunostomy, choledochojejunostomy or choledochoduodenostomy offers durable drainage of an obstructed bile duct. Choledochojejunostomy is less reliable but can be employed when tumor bulk precludes common duct procedure Ref: Devita 9th edition Pgno : 979