Share Didactics Metabolic Support Apr152024.pptx

Schwartz 11 Edition th Chapter 2: Surgery Lecture: Systemic Response to Injury and Metabolic Support z Lecturer: Miguel J. Villanueva, MD, MBA, DPBS General Surgery and Surgical Oncology ...

Schwartz 11 Edition th Chapter 2: Surgery Lecture: Systemic Response to Injury and Metabolic Support z Lecturer: Miguel J. Villanueva, MD, MBA, DPBS General Surgery and Surgical Oncology  Oxidative Citric Acid/ Kreb’s Phosphorylation/ Glycolysis Cycle Electron Transport Chain Mitochondrion Cytosol Mitochondrion Theoretical maximum yield of ATP through oxidation of one molecule of glucose in glycolysis, citric acid cycle, and oxidative phosphorylation is 38 Eukaryotes: Transport of two equivalents of NADH into the mitochondria consumes two equivalents of ATP, thus reducing the net production of ATP to 36. Furthermore, inefficiencies in oxidative phosphorylation provides an estimate of 29.85 ATP per glucose molecule.  Surgical Metabolism: Metabolism During Fasting  Normal healthy adult: 22 to 25 kcal/kg/day  50-55% carbohydrates  10-15% proteins  30-40% fat  As high as 40 kcal/kg/day in severe stress states  Short term fasting: 1.0) can result in conditions such as glucosuria, thermogenesis, and conversion to fat (lipogenesis). Prolonged need for ventilator support, fatty liver, suppression of leukocyte function, hyperglycemia, and increased risk for infection  GLUT 4: Insulin dependent  Protein and Amino Acid Metabolism  1 g of protein: 4 kcal of energy Every 6 g of protein yields approximately 1 g of nitrogen.  The average protein intake: 80 to 120 g/d  After injury: urinary nitrogen excretion