The Metabolic Management of the Critically Ill

ISBN-13: 9781468423846 / Angielski / Miękka / 2012 / 278 str.

Opis

HOW DO I USE THIS BOOK? This book is organized to answer specific questions about the metabolic and nutritional problems of critically ill patients. Thc questions are listed under five chapter headings in the Contents. Each question is self-contained with its own charts, tables, and references, although, in some instances, you may be referred to another section of the book for additional information. A detailed subject outline appears on the first page of each chapter, and there is an index for cross-reference to specific subjects. A metabolic support plan and accompanying metabolic and nutritional worksheet are locatcd in the Appendix. This plan pro- vides the best estimates available for predicting the metabolic requirements of patients, and outlines approaches to feeding the hospitalized patient which will satisfy these nutritional needs. Clin- ical cases are presented in this section to help you get started using the support plan. This volume is a handbook organized for frequent use - place the appropriate tables and nomograms on the bulletin board of the intensive care unit or in your office for convenient reference. Use the metabolic and nutritional support plan and establish the habit of assessing the metabolic requirements of your patients. Refer to the references cited to explore in further detail specific questions or areas of interest. By applying our knowledge of the metabolic and nutritional alterations which occur following disease, we can improve our care of the critically ill.

Spis treści

1. Energy and Energy Balance.- 1.1 What is the body’s efficiency in converting chemical energy into mechanical work? What is the efficiency in energy conversion to heat?.- 1.2 What is a kilocalorie?.- 1.3 What is thermal balance?.- 1.4 How is heat loss from the body measured? What is direct calorimetry?.- 1.5 What is indirect calorimetry?.- 1.6 How is oxygen consumption related to heat production?.- 1.7 How much oxygen is consumed by normal man? How does oxygen consumption affect respiration?.- 1.8 What does total body oxygen consumption measure?.- 1.9 How is oxygen consumption measured?.- 1.10 Can carbon dioxide production be equated to energy production?.- 1.11 What is RQ? Why is it useful?.- 1.12 How is the fuel source of the energy oxidized by the body determined?.- 1.13 What is BMR? What is RME?.- 1.14 How does body size affect metabolic rate? How do we correct for body weight?.- 1.15 Why is metabolic rate related to body size?.- 1.16 How does metabolic rate vary with age?.- 1.17 Does the sex of the individual affect metabolic rate?.- 1.18 How does body temperature affect metabolism?.- 1.19 How does food intake affect metabolism? What is specific dynamic action?.- 1.20 How is the energy expenditure of activity predicted? How is the total daily energy requirement estimated?.- 1.21 What is the effect of ambient temperature on metabolic rate?.- 1.22 What alterations in heat production occur with starvation.- 1.23 To what extent does injury or infection affect energy production?.- 1.24 What is the role of pain, fear, and anxiety in hypermetabolic states?.- 1.25 How can the energy requirements of critically ill patients be estimated?.- 1.26 What is energy balance?.- 1.27 How is energy balance calculated?.- 1.28 How can the weight alterations of patients be predicted?.- 1.29 To what extent is weight loss detrimental?.- 1.30 How is the nutritional status of a patient determined from body weight?.- 2. Control of Body Temperature: Relationships with Metabolic Control.- 2.1 Why measure oral or rectal temperature?.- 2.2 What is normal body temperature? What are the variations in body temperature around normal?.- 2.3 How is core temperature measured?.- 2.4 How are mean skin temperature and mean body temperature determined?.- 2.5 How is heat lost from the body?.- 2.6 How is evaporative water loss measured?.- 2.7 How does fever affect evaporative water loss? What other diseases alter insensible water loss?.- 2.8 What are the routes of dry heat loss?.- 2.9 How does man insulate between his skin and the surrounding environment?.- 2.10 What determines heat flow to the body surface? What is conductance?.- 2.11 What alterations in core—skin heat transfer are observed in patients?.- 2.12 How does the brain control body temperature?.- 2.13 What is temperature setpoint? What factors alter setpoint?.- 2.14 What are the mediators which alter central temperature setpoint?.- 2.15 How does infection stimulate increased oxygen consumption?.- 2.16 What are the mediators of the febrile response to infection? What is endogenous pyrogen? How does it differ from exogenous or bacterial pyrogen?.- 2.17 What is posttraumatic fever? How should it be controlled?.- 2.18 What other disease processes cause fever?.- 2.19 Should patients have fever? When should fever be treated? How?.- 2.20 What is the relationship between fever and body catabolism?.- 2.21 What is the relationship between pulse rate and fever?.- 2.22 What drugs affect temperature setpoint?.- 2.23 Why do patients become hypothermic in the operating room?.- 2.24 How do electrolytes alter body temperature? What hormones affect temperature setpoint?.- 2.25 How is temperature control related to metabolic control?.- 2.26 Is there evidence for altered hypothalamic function following stress?.- 2.27 Does the altered hypothalamic function in stressed man affect thermoregulation?.- 2.28 What stimulates the hypothalamus to produce “post-traumatic fever”?.- 2.29 How is blood glucose related to body temperature and heat production?.- 2.30 What is heat exhaustion? Heat stroke? How are the heat overload syndromes treated?.- 2.31 What is the role of physical activity and dehydration in overheating?.- 2.32 What are the symptoms and treatment of malignant hyperthermia which occurs during anesthesia?.- 2.33 What causes accidental hypothermia? How is it treated?.- 2.34 How does alcohol cause hypothermia?.- 2.35 Why do patients with gram-negative infection become hypothermic?.- 3. Hormonal Control of Body Fuels.- 3.1 What are hormones?.- 3.2 What are the storage hormones? What are their effects? What are the mobilizing hormones?.- 3.3 How is insulin stored? Released? What is the half-life of insulin?.- 3.4 How is insulin measured? How is the insulin response to glucose assessed?.- 3.5 How is the functional effect of insulin on peripheral tissue determined? What is the instantaneous proportionality constant for glucose disappearance, or k?.- 3.6 What is the effect of insulin on glucose metabolism?.- 3.7 How does insulin affect fat metabolism? Protein metabolism?.- 3.8 What substances stimulate insulin release? What hormones affect insulin elaboration?.- 3.9 How does the autonomic nervous system affect the endocrine pancreas?.- 3.10 What are the metabolic effects of glucagon? What is the I/G ratio?.- 3.11 What stimulates glucagon release?.- 3.12 Is glucagon the hormone of stress?.- 3.13 How are catecholamines synthesized, stored, and released?.- 3.14 How is catecholamine activity assessed?.- 3.15 Why are catecholamines called the hormones of stress?.- 3.16 What are the general effects of sudden sympathetic nervous system discharge? What are the effects of epinephrine and norepinephrine infusion in man?.- 3.17 What are alpha and beta receptors? How are they determined? What do they do?.- 3.18 How do catecholamines stimulate hyperglycemia?.- 3.19 How do catecholamines affect fat mobilization?.- 3.20 Do catecholamines stimulate heat production?.- 3.21 What stimulates heat production in the critically ill patient?.- 3.22 What limits the body’s response to catecholamine-mediated stimuli?.- 3.23 What stimulates ACTH? What is the function of ACTH?.- 3.24 How is Cortisol transported in the blood?.- 3.25 How are the corticosteroids classified?.- 3.26 What are the primary effects of glucocorticoids on metabolism?.- 3.27 Are glucocorticoids the hormones responsible for negative nitrogen balance following injury?.- 3.28 Do the antiinflammatory effects of corticosteroids influence the body’s systemic response to infection or injury?.- 3.29 Does increased growth hormone elaboration occur following stress?.- 3.30 What are the actions of growth hormone?.- 3.31 Can the anabolic effects of growth hormone reverse the catabolic effects of injury and infection?.- 3.32 Is thyroid hormone an anabolic or a catabolic agent? What is its function?.- 3.33 Is T3 or T4 a stress hormone?.- 4. Alterations in Intermediary Metabolism.- 4.1 What events follow ingestion of a meal?.- 4.2 How does the body store energy?.- 4.3 How does man respond to short-term starvation? What is the Cori cycle?.- 4.4 What causes “ketosis”? Is it beneficial? Harmful?.- 4.5 How do the blood substrates change during fasting? How does this reflect alterations in oxidized fuels?.- 4.6 What hormone controls substrate flow during brief fasting?.- 4.7 How does man adapt to longer periods of starvation? What is the time course for starvation adaptation?.- 4.8 Are renal function and metabolism affected during prolonged starvation?.- 4.9 What is the alanine cycle?.- 4.10 How is the nitrogen lost during starvation affected by glucose? By ingestion of amino acids? Of fats?.- 4.11 What are the body compositional changes that occur during partial or total starvation?.- 4.12 What are some of the alterations in organ composition following starvation?.- 4.13 What important physiological consequences are associated with semi- or total starvation?.- 4.14 What is the relationship between infectious disease and undernutrition?.- 4.15 How do the metabolic events change with time following injury or infection?.- 4.16 What factors direct the metabolic response to injury? To infection?.- 4.17 What are the characteristic metabolic alterations which are associated with injury and surgical infection?.- 4.18 What are the routes of protein loss from the body following trauma or infection?.- 4.19 Where does the protein excreted in the urine originate?.- 4.20 What determines the magnitude of the nitrogen excreted in the urine? How is this related to oxygen consumption? To other factors?.- 4.21 How do preinjury body composition and protein stores affect the magnitude of the nitrogen excreted following stress or starvation?.- 4.22 How is nitrogen excretion affected by bed rest and muscle activity?.- 4.23 How does starvation affect nitrogen excretion following uncomplicated operations? Following complicated cases of injury and infection?.- 4.24 Is the nitrogen loss following severe injury the result of decreased protein synthesis or increased protein breakdown?.- 4.25 What are the hormonal regulators of muscle proteolysis following injury and infection? How is proteolysis related to increased ureagenesis?.- 4.26 What disease processes increase metabolic rate?.- 4.27 What is the mediator of the increased oxygen consumption following injury?.- 4.28 Does evaporative water loss following thermal injury cause increased heat production? What is the role of environmental temperature in treating severely injured patients?.- 4.29 What alterations in glucose dynamics occur following critical illness?.- 4.30 How does the insulin response vary during the acute and hypermetabolic phases of injury?.- 4.31 What is the regulator of hepatic gluconeogenesis?.- 4.32 What alterations in glucose dynamics occur during convalescence?.- 4.33 How are glucose dynamics altered with infection? With gram-negative sepsis complicating injury?.- 4.34 How is heat production related to increased glucose flow? Is the increased glucose flow necessary to provide an oxidized fuel?.- 4.35 What tissue components of the body are associated with weight loss following injury or infection? Is postinjury weight loss obligatory?.- 4.36 What alterations in intermediary metabolism occur during exercise? How does this response differ from the changes which occur in critically injured man?.- 4.37 What alterations in intermediary metabolism occur with cold exposure?.- 5. Feeding the Patient.- 5.1 Has vigorous nutritional support always been provided to critically ill patients? What evidence suggests that it is essential to patient care?.- 5.2 How prevalent is hospital malnutrition? Why does it occur?.- 5.3 How does malnutrition impair the patient’s response to disease?.- 5.4 How is the extent of malnutrition or starvation best quantitated in man?.- 5.5 What are the indications for vigorous nutritional support of hospitalized patients?.- 5.6 What are the best recommendations available for achieving adequate nutrition in normal individuals?.- 5.7 How are the specific energy requirements of the hospitalized patient determined?.- 5.8 How should the calorie requirements be met by specific dietary provisions?.- 5.9 What are the advantages of carbohydrate in enteral diets?.- 5.10 What are the advantages of intravenous dextrose with or without insulin therapy administered to critically ill patients?.- 5.11 What are the hazards of high carbohydrate diets? Of intravenous glucose?.- 5.12 What is the ideal intravenous sugar? What are the rates of utilization of various sugars in intravenous diets?.- 5.13 Why is dietary fat desirable? Undesirable?.- 5.14 What is essential fatty acid deficiency? How is it treated?.- 5.15 What are medium-chain triglycerides? How does their metabolism differ from long-chain fatty acids?.- 5.16 What are the side effects associated with administration of intravenous fat emulsions? What are the contraindications for infusing fat emulsion?.- 5.17 How are the nutritional effects of dietary proteins assessed?.- 5.18 What is nitrogen balance? What is cumulative nitrogen balance? What are the errors in the measurement?.- 5.19 How is nitrogen balance affected by nitrogen intake? By energy intake?.- 5.20 What are the labile protein stores? What is meant by visceral protein?.- 5.21 How are amino acids metabolized following oral feeding? Following intravenous feeding?.- 5.22 Is infused plasma or albumin utilized as dietary protein?.- 5.23 How is the efficacy of various proteins assessed? What is the biologic value of protein?.- 5.24 How are the dietary requirements for protein determined? How do they relate to caloric intake? What is the nitrogen: calorie ratio?.- 5.25 How do carbohydrate and fat influence nitrogen balance?.- 5.26 How is nitrogen excretion altered with changes in energy expenditure?.- 5.27 What are the essential amino acids? What is the proportion of essential to nonessential nitrogen required in a diet?.- 5.28 How do essential amino acids alone affect nitrogen balance in renal failure? Is urea reutilized for protein synthesis?.- 5.29 What are the alpha-keto analogues of the essential amino acids? How are they utilized?.- 5.30 How is liver failure affected by the intake of protein? How can hepatic coma be modified by specific amino acid therapy?.- 5.31 What are the vitamin requirements in normal individuals? In critically ill patients? How are they best provided?.- 5.32 What minerals and trace elements should be provided in diets for the critically ill patient?.- 5.33 What is the composition of the usual hospital diet? How is it altered to satisfy specific nutritional requirements?.- 5.34 How are dietary supplements best administered? How should they be given? What should be given?.- 5.35 What are the indications for tube feedings? How are they administered? What are the hazards?.- 5.36 What are bulk-free, chemically defined diets? When should they be utilized?.- 5.37 When should intravenous feedings be initiated?.- 5.38 What are the best recommendations for intravenous nutrient administration? How are the requirements best provided?.- 5.39 How are hypertonic fluids for intravenous nutrition planned?.- 5.40 What precautions should be taken when starting hypertonic glucose and amino acid infusions?.- 5.41 When is complete intravenous nutrition administered by peripheral vein indicated? What are the advantages and disadvantages of complete nutrition by peripheral vein?.- 5.42 How are fat emulsions administered?.- 5.43 Can intravenous fat emulsion be utilized as a component in nutrition administered by central venous route?.- 5.44 What is the effect of infusing hypocaloric solutions containing amino acid on nitrogen balance?.- 5.45 How should a febrile episode during central venous parenteral feedings be handled?.- 5.46 What are the metabolic complications that occur with intravenous feedings? What monitoring methods are necessary to assure safe intravenous nutrition?.- 5.47 When should combined enteral—parenteral feedings be administered? How?.- 5.48 What adjunctive measures should be initiated with dietary therapy?.- Appendix: Metabolic Support Plan — Using the Metabolic and Nutritional Worksheet.- 1. Peritonitis in a patient with inflammatory bowel disease.- 2. Multiple trauma in a young, healthy male.- 3. A small burn injury in a depleted woman.- 4. Intraabdominal postoperative complications: Edematous patient referred to your service after 2 weeks of semistarvation.- 5. Parenteral nutrition following injury and renal failure.- 6. Hepatic dysfunction in a patient with an enterocutaneous fistula receiving intravenous feedings.- 7. Bacteremia in a patient with severe peritonitis: Managing nutritional requirements, hyperglycemia, the intravenous catheter, and fever.- 8. Edema, hypoproteinemia, and malnutrition following blunt abdominal trauma and small bowel resection.