The pancreas and oxygen consumption. 1. Pancreatic oxygen consumption in normo- and hypovolemic dogs

Pancreatic oxygen consumption (VO2) was studied in hypovolemic shock: 4 dogs served as controls and 4 others were kept at 50 mm Hg of mean arterial blood pressure. All 8 were studied for a period of 3 h. Pancreatic VO2 was obtained by adding up VO2 for the head (minus the uncinate process) and tail of the pancreas both equal to the product of regional blood flow times O2 extraction. Regional blood flows were measured electromagnetically on the gastroduodenal (GDA) and the splenic (SA) arteries, whereas O2 extraction was derived from total hemoglobin (THb) and oxygen saturation of hemoglobin (%O2 Hb) determined on the right femoral artery (RFA), the superior pancreaticoduodenal (SPDV), and splenic (SV) veins. A splenectomy was performed in all 8 dogs. Controls showed a significantly elevated pancreatic VO2 from the first hour of observation on (+56% after 1 h, +92% after 3), whereas pancreatic VO2 remained strictly unchanged throughout shock (+2% and +6%, at one and 3 h, respectively), despite significant increases in O2 extraction. These findings give support to the deleterious effects of hypovolemia to the pancreas and that pancreatic O2 extraction indicates metabolic damage to be less severe than observed in experimental bile-trypsin-induced acute pancreatitis.