<prompt> A patient in the emergency room with a road traffic accident has retroperitoneal bleed. Trauma to which of the following structures is most likely the cause of the bleedLiverStomachJejunumPancreas  <response>: The pancreas is the most likely cause as it is a retroperitoneal structure.All the structures listed are intraperitoneal Relationship of the viscera the peritoneum: INTRAPERITONEAL:Stomach,jejunum,ileum,caecum,appendix,transverse colon, sigmoid colon, liver, gall bladder, spleen RETROPERITONEAL:Esophagusabdominal,duodenum 2 ND and 3rd pa, pancreas, kidney, ureter, suprarenal glands, abdominal aoa, and its branches ,inferior Vena cabs, and Celiac plexus PAIALLY COVERED IN THE PERITONEUMalso considered as retroperitoneal :Ascending colon, descending colon, rectum RETROPERITONEAL STRUCTURES retroperitoneal structures are posterior to the peritoneal sac and do not have a Mnemonic:SAD PUCKER S-suprarenal gland A-aoa D-dudenum 2nd and 3rd pa P-pancreas except the tail C-celiac plexus and colon ascending and descending colon K -kidneys E -esophagus Reference:Grays anatomy,41st edition page number 1045 andv1046 