Medical Nutrition Therapy Final Exam Study Guide Spring 2014 There will be 100 multiple choice and true false questions each worth 1 point 55 will be old material and 45 will be new material Metabolic stress What is Metabolic Stress o involves most metabolic pathways o Accelerated metabolism of lean body mass leads to 1 Negative nitrogen balance 2 Muscle wasting o Involves ebb and flow phases What is Ebb phase o Immediately following injury o Symptoms hypovolemia shock tissue hypoxia o May last 2 24 hours depending on the type and extent of injury o Decreased BP and cardiac output volume of blood flow through the heart o Decreased oxygen consumption o Decreased body temperature o Insulin levels Decrease because glucagon is elevated to increase hepatic glucose production Flow phase o Follows fluid resuscitation and restoration of oxygen transport body adjusts to injury o Increased cardiac output begins o Increased body temperature o Increased energy expenditure o Total body protein catabolism begins o Marked increases in glucose production FFA release circulating insulin catecholamines epinephrine and norepinephrine glucagon and cortisol What are the different types of MS o Sepsis infection Leads to systemic inflammation 1 When a pt has a documented infection and an identifiable organism 2 3 Caused by bacteria viruses fungi and parasites 4 Bacteria and their toxins cause stronger inflammatory responses o Trauma includes motor vehicle accidents burns gunshots stab wounds and falls o Surgery o When the systemic response is activated the physiologic and metabolic changes that follow are similar and may lead to septic shock Know the hormonal and cell mediated response during MS o Hormones cause protein catabolism 1 Glucagon promotes gluconeogenesis amino acid uptake ureagenesis and protein catabolism 2 Cortisol enhances skeletal muscle catabolism and promotes use of amino acids for glucogenogenesis glycogenolysis and acute phase protein synthesis o BCAAs to synthesize muscle glutamine carbon skeletons used in glucose alanine cycle o Mobilization of acute phase proteins causes rapid loss of LBM negative nitrogen balance o Urinary loss of potassium phosphorus magnesium due to skeletal muscle breakdown o Increased circulation of FFAs from increased lipolysis due to elevated cortisol catecholamines and glucagon o Hyperglycemia caused by elevated gluconeogenesis and elevated levels of hormones e g epinephrine that diminish insulin release o Sodium and water retention due to increased aldosterone and antidiuretic hormone o Cytokines interleukin IL 1 IL 6 tumor necrosis factor cause hepatic amino acid uptake and protein synthesis increased muscle breakdown and induce gluconeogenesis o Serum iron and zinc levels decrease due to sequestration and increased urinary zinc excretion Organ Liver Metabolic Responses During Sepsis Response glucose production gluconeogenesis amino acid uptake acute phase protein synthesis trace metal sequestration Central Nervous System Anorexia fever Circulation Skeletal muscle Intestine Endocrine glucose triglycerides amino acids urea ureagenesis Iron due to sequestration Zinc sequestration and urinary excretion Amino acid efflux esp glutamine leading to loss of muscle mass Amino acid uptake from both luminal and circulating sources leading to guy mucosal atrophy Adrenocorticotropic hormone cortisol Growth Hormone Epinephrine Norepinephrine Glucagons Insulin usually What are the differences between starvation and stress o Starvation 1 Decreased energy expenditure use of alternative fuels decreased protein wasting stored glycogen used in 24 hours and then muscle protein used for glucose production 2 Diminished gluconeogenesis increased ketone body production decreased ureagenesis 3 Late starvation fatty acids ketones and glycerol provide energy for all tissues except brain nervous system and RBCs o Stress increased energy expenditure gluconeogenesis proteolysis and ureagenesis 1 Hypermetabolic state stress causes accelerated energy expenditure glucose production glucose cycling in liver and muscle o Hyperglycemia can occur either from insulin resistance or excess glucose production via gluconeogenesis and Cori cycle o Muscle breakdown accelerated also Starvation Resting energy expenditure Decreased Respiratory quotient 0 6 0 7 Mediator activation Fat Primary fuels Proteolysis BCAA oxidation Hepatic protein synthesis Ureagenesis Urinary nitrogen loss Gluconeogenesis Ketone body production pathophysiology of SIRS Stress Hypermetabolism Increased 0 8 0 9 Mixed What is SIRS Describe the signs and o Widespread inflammatory response that occurs in infection pancreatitis ischemia burns multiple trauma hemorrhagic shock and organ injury o Inflammation present in areas away from primary site of injury o MODS or Multiple organ dysfunction syndrome is a common complication 1 Begins with lung failure and leads to liver intestine and kidney failure 2 May be accompanied by hematologic myocardial and central nervous system failures o Signs or SIRS Low oxygen consumption 1 Patients are hypermetabolic 2 High cardiac output 3 4 High venous oxygen saturation 5 Lactic academia 6 Massive edema 7 Decreased plasma protein concentrations o Pathophysiology 1 Excessive production of pro inflammatory cytokines 2 Gut hypothesis Injury or disruption of gut barrier function Translocation of enteric bacteria into the mesentery lymph nodes liver and other organs 3 Shock causes gut hypo perfusion which increases pro inflammatory molecule production 4 Causes ileus lack of peristalsis in stomach and small bowel MNT for SIRS and MODS o Goals 5 Enteral feeding restores gut function by enhancing functional and structural integrity of the gut 6 Enteral nutrition maintains tight junctions between the intraepithelial cells stimulating blood flow and inducing the release of trophic factors o Diagnosis site of infection established and at least two of the following are present 1 Body temperature 38 C 100 4 F OR 36 C 96 8 F 2 Heart rate 90 beats min 3 Respiratory rate 20 breaths min tachypnea 4 PaCO2 32 mmHg hyperventilation 5 WBC count 12 000 mm3 OR 4000 mm3 6 Bandemia presence of 10 bands immature neutrophils in the absence of chemotherapy induced neutropenia and leukopenia 1 Minimize starvation 2 Prevent or correct specific nutrient deficiencies 3 Provide adequate kcals 4 Manage fluid and electrolytes 5 Begin enteral feeding when hemodynamically stable the maintenance of airway and breathing adequate