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326 Cards in this Set
- Front
- Back
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Define: Clinical Nutrition
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The branch of nutrition specifically related to providing nutritional care in disease
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Define: Etiology
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The cause/set of causes of a disease/condition
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Define: Pathogenesis
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The manner of disease development
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Define: Prognosis
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The likely course of a disease
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Acute vs. Chronic
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Chronic: develops and worsens over an extended period of time. May be asymptomatic - Example: atherosclerosis Acute: symptoms are severe and sudden in onset. For example, heart attack. |
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Sign vs. Symptom
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Signs: Objective indicators of disease. Includes lab values, anthropometrics, etc. Symptoms: Subjective indicators of disease that cannot be measured |
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Name the four components of the nutrition care process (NCP)
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1. Nutrition Assessment 2. Nutrition Diagnosis 3. Nutrition Intervention 4. Nutrition Monitoring/Evaluation |
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Describe Nutrition Assessment and the five components
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Initial and ongoing process of collecting and analyzing nutritional information. 1. Food/Nutrition related history 2. Anthropometric Measurements 3. Biochemical Data, Medical Tests, Procedures 4. Nutrition Focused Physical Findings 5. Clint History (medical, family, social, personal) |
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Define Primary Nutrient Deficiency
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Deficiency caused by insufficient intake
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Define Secondary Nutrient Deficiency
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Deficiency caused by a factor other than insufficient intake. For example, impaired nutrient absorption by meds or disease.
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Describe Nutrition Diagnosis
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Description of the problem for which the primary intervention will address. Expressed as a PES Statement.
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Explain PES statement
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Problem related to Etiology as evidenced by Symptoms |
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Describe Nutrition Intervention
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Planning and implementing to elicit change through a client driven approach (may be more than one). Expressed as a nutrition prescription which may address immediate diet, any supplementation required, plans for education/counselling, and plans for discharge/followup
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Describe Nutrition Monitoring and Evaluation
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Monitoring the client's progress and effective indicators (including nutrition outcomes, health outcomes, and patient centered outcomes). Furthermore, this looks at implementation, understanding, and if it is the right plan.
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Define BMR and describe the ideal conditions for measurement
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Basal metabolic rate - best measured just after waking after fasting for twelve hours and no exercise. Comfortable temp
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Define RMR and explain measurement
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Resting metabolic rate - measured after 30 minutes of resting. Measures O2 consumed and CO2 output in breath.
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What does O2 consumed indicate?
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Can be used to determine RMR's caloric equivalent
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What does the Respriatory Quotient (RQ) stand for and indicate
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RQ = Volume CO2 produced: O2 consumed Value of 1: 100% CHO burning Value of .8: Mixed fat and CHO Value of .7: 100% fat burning |
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List the four components of energy expenditure
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1. BMR ( RMR is 15% higher) 2. Physical Activity 3. Thermic Effect of Food (10 to 15%) 4. Stress |
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What is the activity factor for a bedridden patient?
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1.1 - 1.2
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What is the adult Protein RDA? What influences this
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0.8 g/kg Influenced by stress, malnourishment, non-protein energy percentage |
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Define: Disease
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process that interferes with/disrupts the body's normal function
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Define Pharmacology
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The study of drugs and their properties and effects |
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Define Pharmacokinetics
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The study of drug absorption, distribution, metabolism and excretion
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What are Cytochrome P450 mixed-function oxidases?
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A group of hepatic enzymes largely involved in hepatic drug metabolism
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Define xerostomia
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Dry mouth due to decreased saliva production
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Describe how proton pump inhibitors interfere with B12.
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PPIs interrupt acid production in the stomach and impair B12 absorption.
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Describe the effect of cholestyramine on absorption of nutrients.
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Cholestyramine is a drug used to modify serum lipids. It forms a complex with bile acids and is excreted in feces. This reduces the availability of bile acids for absorption and can result in steatorrhea and decreased fat soluble vitamin absorption.
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Describe the effect of Isoniazid on nutrient metabolism.
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Isoniazid is used to treat TB and can decrease B6 (pyridoxine) synthesis, therefore supplementation is recommended.
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Describe the effect of warfarin on nutrient metabolism.
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Warfarin prevents hepatic reductase from converting the storage form of vitamin K to the active form which can prevent thrombosis. High doses of vitamin K decreases the effectiveness of these drugs therefore consistent intake is recommended.
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Describe the effect of glucocorticoids on nutrient metabolism.
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These anti-inflammatory agents increase gluconeogenesis, decrease glucose uptake from blood (increased BG), decrease protein synthesis and increase protein degredation
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Describe the effect of antiepileptic agents on nutrient metabolism. |
These agents result in a folate deficiency by increasing folate turnover (enzyme induction). This is treated with small dose supplementation or folate rich diet.
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What diuretics are potassium sparing?
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spironolactone
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What diuretics are potassium depleting
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thiazides, furosemide
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Define Drug Interaction
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Alteration of drug activity as a result of another agent administered prior or concurrent to the drug.
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Describe Drug Related Outcomes of a Drug Interaction
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- Increased drug activity - toxicity? - decreased drug activity - therapeutic failure - most common outcome: generally undetectable |
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Name and describe the mechanisms of drug nutrient interactions (3)
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1. pharmaceutical - occurs before drug administration 2. pharmacokinetic - impacts absorption, distribution, metabolism or excretion of the drug 3. pharmacodynamics - impacts drug activity at the receptor level |
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Name the variables that can influence a food drug interaction (3)
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1. Food composition 2. Drug's properties 3. Patient variability |
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List the impact drug metabolizing enzymes have on pharmacokinetics
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Pharmacokinetics (drug absorption, distribution, metabolism, and excretion). Drug metabolizing enzymes influences absorption and metabolism. |
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List the impact of drug transporters on pharmacokinetics.
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Pharmacokinetics (absorption, distribution, metabolism, excretion) Drug transporters influence absorption, distribution, and excretion. |
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What is the rate limiting step of drug absorption?
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Dissolution (dissolving time)
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What is the major site of oral drug absorption? Name and describe two main transport mechanisms.
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Small intestine 1. ATP Binding Casette - part of enterocytes. Limits absorption by returning absorbed components back into the small intestine 2. Solute linked carriers - uptake transporter |
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Explain the first pass effect (FPE)
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Part of the active drug is lost in the GI tract and during the first pass through the liver before it enters systemic circulation. This determines the bioavailability of oral drugs.
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Describe the outcome of altered rate of drug absorption.
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The amount absorbed is not changed, just the speed. This only matters when the therapeutic relies on a specific absorption rate (such as in the case of allergy meds or pain meds)
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Describe the outcome of altered bioavailability of a drug.
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This results in an increased or decreased amount of drug absorption. This can result in more or less drug reaching systemic circulation.
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What is the effect of a balanced meal on the GI tract?
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Delayed gastric emptying, increased secretions, increased GI motility, increased fluid volumes.
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Describe the potential negative effect of a meal on drug absorption.
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1. Delayed response due to slowed absorption 2. Increased breakdown of drug (reduced absorption) or Increased complexation with food constituents (decreased absorption) 4. Premature release of enteric coated drugs (due to prolonged gastric exposure) or Delayed release due to retention of undissolved tablets in the stomach 6. poorly soluble drugs have time to adequately dissolve properly/aided by bile acids |
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What is the rule of thumb for chronic drugs?
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Timing relative to meals should be consistent. Drugs that have decreased bioavailability by meals should be taken 1 hour before or 2 hours after. Drugs that have increased bioavailability by meals should be taken WITH or immediately after meals |
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What metalic ions form chelates with susceptible drugs and are excreted in feces? Name two important examples and how to avoid this. |
- Al, Ca, Fe, Mg, Zn - antibiotics, biphosphonates - avoided by taking drugs on an empty stomach or 1 hr before meal/2 hrs after meal/dairy |
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Describe the impact of fibre on drug absorption.
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Fibre can decrease absorption by binding drugs OR increase absorption by increasing transit time (decreases breakdown) OR increase absorption by inhibiting enzyme breakdown
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Phase I drug metabolism - describe
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Cytochrome P4500 (CYP) family - responsible for majority of metabolized drug
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Phase II drug metabolism - describe
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UDP-glucuronosyltransferases (UGTs) - small percentage of drug metabolism
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Describe sites of drug metabolism
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Primarily liver but also in GI and lungs, skin and kidneys. Diet has a role in regulating expression and function of enzyme genes
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Effect of Increased CHO or Fat on drug metabolism
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Decreased metabolism of active drugs resulting in increased serum levels of the active drug
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Effect of increased protein on drug metabolism
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Increased drug metabolism of the active drug leading to decreased serum levels of the active drug
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What phytochemicals in fruts/vegetables may inhibit/induce metabolic enzymes or transporters
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Polyphenols, carotenoids, curanocoumarins, glucosinolates
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What transporters and enzymes does grapefruit juice inhibit? What is the impact?
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transporters - p-glycoprotein, OATP enzyme - CYP3A4 Impact: significant increase or decrease in bioavailability |
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List 2 drugs that have increased bioavailability by grapefruit juice
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Amlodipine (hypertension), lovastatin (dyslipidemia)
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Name a drug with decreased bioavailability by grapefruit juice
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OATP inactivation decreases absorption of fexofenadine (antihistamine)
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Name two fruits that inhibit the OATP family
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Grapefruit, oranges
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Name four fruits that inhibit the CYP family
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Grapefruit, apples, cranberries, grapes
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Name two vegetables that inhibit CYP enzymes and Induce phase II enzymes and describe the effect.
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broccoli, cauliflower - decreases absorption rate and breakdown rate which could lead to therapeutic failure
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Name a vegetable that inhibits CYP enzymes and p glycoprotein and explain the effect
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Watercress - slows absorption
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Name three nutrients important for drug function and explain the long term/short term effects of deficiency/super dose.
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Vitamin C, Folate, and pyrioxine - long term deficiency: may lead to decreased drug clearance (toxicity) - short term mega dose: may lead to increased drug clearance (therapeutic failure) |
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What is the theoretical effect of a low protein diet on drug distribution?
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Drugs are often bound (therefore inactive) to plasma proteins. Low protein levels would decrease plasma concentrations of proteins and theoretically result in higher drug activity.
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What is the effect of low protein on drug excretion?
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Low protein results in urine pH rising and less drug being excreted. |
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Describe the interaction between sodium and lithium.
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Lithium (bipolar drug) is excreted at the same rate as sodium. In some cases it leads to sodium depletion, which results in higher levels of both sodium and lithium being reabsorbed by the kidneys. This can lead to toxic build up of lithium. |
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What is a pharmacodynamic interaction and what are the potential effects?
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alteration of drugs at receptors - this may lead to addiction (increased therapeutic effect, toxicity/side effects) OR antagonistic effect (decreased therapeutic effect).
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What is an MAOIs
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Monoamine oxidase inhibitor - antidepressant that increases tyramine absorption/norepinephrine build up in neurons.
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Describe the interaction between MAOIs and dietary tyramine
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Tyramine stimulates the release of norepinephrine which increases blood pressure causing headaches, palpitations, nausea, vomiting, or increase the risk of MI/Stroke
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Name six sources of tyramine
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cheese, salami, sauerkraut, fermented soy products, high protein yeast/meat extracts, meat and fish which are "off"
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Name 3 sources of vitamin K
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Leafy greens, tomatoes, fermented foods
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Describe the effect of potassium depleting diuretics
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May lead to hypokalemia which is especially concerning when combined with digoxin as it can lead to heart failure or arrhythmias
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Name eight supplements that with anticoagulent properties that can interfere with warfarin.
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garlic, cayenne pepper, turmeric, cloves, ginger, flax oil, fish oil, resveratrol
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Describe the effects of potassium sparing diuretics when combined with ACE inhibitors
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May lead to hyperkalemia which can cause heart failure and hypertension
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What drug does calcium/vitamin D have an inhibiting effect on?
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inhibits antihypertensives
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What is the role of folate in antidepressants?
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Antidepressants seem to be amplified by folate. More research is needed to determine the dose and effects of high doses. |
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What is the role of folate with nitroglycerine?
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Nitroglycerine can be tolerated quite quickly and 8 to 12 hour breaks are needed to prevent tolerance. Folate supplementation seems to decrease the need for nitrate free periods.
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What program tracks drug interactions in Canada?
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Health Canada's post market surveillance program
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What is Diabetes?
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A set of metabolic conditions characterized by the presence of hyperglycemia due to defective insulin secretion AND/OR defective insulin action
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What is a characteristic of uncontrolled T1DM that is not common with T2DM
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Ketoacidosis
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Describe Ketoacidosis symptoms and pathophysiology
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symptoms: fruity breath (acetone), rapid deep respiration, lethargy, coma pathophysiology: Prolonged elevated blood glucose and starving cells results in increased lipolysis. This causes rising serum levels of ketones which cause the pH to fall. In order to compensate breath becomes shallow and deep and bicarbonate is released from bones. Eventaully the central nervous system is depressed and ketoacidosis can lead to coma then death. |
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Distinguishing factors between T1DM and T2DM
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T1: insulin dependent for life, prone to ketoacidosis T2: not insulin dependant but uses insulin for control |
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Define Glucotoxicity
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Develops after prolonged high blood glucose. An acquired defect where insulin levels are lowered and insulin resistance increases
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What are the inhibitory effects of insulin? What happens when uncontrolled diabetes is present?
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Insulin causes a decrease in: glycogenolsysis, gluconeogenesis, lipolysis, ketogenesis, amino acid catabolism *in uncontrolled diabetes the effect is reversed |
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What are the inducing effects of insulin? What happens when uncontrolled diabetes is present?
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Increased target tissue glucose uptake, glycogenesis, fatty acid synthesis in the liver, and triglyceride storage in adipose tissue, protein synthesis. Reversed by uncontrolled diabetes |
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What are the diagnostic tools for diabetes?
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fasting plasma glucose, A1C, random plasma glucose, oral glucose tolerance test
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What is the most common anihyperglycemic agent for treating diabetes? Describe what it does
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Metformin - improves A1C by enhancing insulin sensitivity in both the liver and peripheral tissues. Associated with a B12 deficiency
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Bolus (Prandial) Insulin is used? Name two examples
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Taken ten to fifteen minutes before a meal. Onset is rapid and insulin is short acting. Examples: rapid acting insulin analogues and short acting insulin |
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Basal Insulins is used? Name two examples
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Taken before bed with a snack. Lasts anywhere from eighteen to thirty hours. Examples: Intermediate acting insulins, long acting basal insulin analogues |
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Premixed Insulins?
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Contain a fixed ratio of insulin and are typically used for type two diabetes as there is less flexibility. |
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Name and describe two insulin regimes
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Single Injection: Usually used for T2DM in conjunction with meds Multi Injection: Varies from conventional (one to two injections per day before supper and/or breakfast) to intensive (four or more shots per day with meals and before bed with a snack. Dose is calculated based on CHO intake, carbs, and exercise) |
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Diabetes recommended intake percentages for soluble fibre, protein, and fat
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12 to 25 g/1000kcal fibre, 15 to 20% fibre (0.8g/kg if kidney disease), no more than 7% saturated fat
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Describe the neurogenic symptoms (epinephrine caused) of hypoglycemia:
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trembling, palpitations, sweating, anxiety, hunger, nausea, tingling
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Describe the neuroglycopenic (glucose deficient nervous system) symptoms:
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difficulty concentrating, confusion, weakness, drowsiness, vision changes, difficulty speaking, headaches, dizziness
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Name the chronic masrovascular complications of diabetes
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coronary heart disease,peripheral vascular disease
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Name the chronic microvascular complications of diabetes
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nephropathy, retinopathy, neuropathy
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Describe enteral nutrition (EN):
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Feeding through the GI tract by a tube/catheter delivering nutrients distal to the oral cavity when patients cannot meet their needs with oral intake alone.
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What is the benefit of trophic/trickle nutrition when EN is not successful alone
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Preserves villi
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Name 8 contraindications of EN
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1 - GI obstruction 2 - GI Ileus 3 - Severe, uncontrolled GI bleed 4 - severe, uncontrolled diarrhea 5 - uncontrolled vomitting 6 - GI inflammation requiring bowel rest 7 - GI Ischemia 8 - Insufficient GI absorption |
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What is the max duration for EN through a naso/orogastric tube?
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six weeks
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Name the three requirements for a nasogastric tube
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normal gag reflex, normal gastric motility, normal gastric emptying rate
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Name 3 pros, and 3 cons of a naso/orogastric EN tube?
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pros: easy to place, easy to confirm placement, low cost cons: tube is easily displaced, increased aspiration risk, nasal irritation |
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Why does a naso/orogastric tube increas the risk of aspiration
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Tube holds open the upper and lower sphincter and the epiglottis making it easier for food to move in the wrong direction
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Name risk factors for pulmonary aspiration (4) |
delayed stomach emptying, GERD, decreased consciousness w/ depressed gag/cough reflex, impaired congition
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How is a nasointestinal (nasoduodenal/jejunal) tube placed?
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A physician places the tube and confirms placement with an xray
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What do ostomy and stoma mean?
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ostomy: location of tip stoma: location of tube end opening |
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How is a gastrostomy/jejunostomy placement made?
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The procedure may be surgical. While the patient is sedated/under anesthesia, an opening (stoma) is made in the abdominal wall through to the stomach/jejunum and a tube is placed.
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How is a percutaneous endoscopic gastrostomy (PEG)/jejunostomy (PEJ) done?
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A needle puncture is made by a gastroenterologist/surgeon and the tube is placed. The procedure is non surgical. This option is more permanent and used when dysphagia is present. |
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What is a polymeric formula?
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Enteral formula designed to meet the needs of someone with adequate GI function. Components are not predigested.
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What needs to be considered when choosing an enteral formula? (6)
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GI function, formula characteristics (osmolarity, viscosity relative to tube size), nutrient density, macronutrient distribution, fluid/electrolyte needs/restrictions, cost
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Name the four main CHOs in polymeric formulas
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monosaccharides, oligosaccharides, dextrins, maltodextrins. No lactose
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Name the five typical sources of medium/long chain fatty acids in EN Formula
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canola, soy, safflower, corn, fish
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What is a hydrolyzed/elemental formula?
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A EN formula for those with impaired digestion/absorption. This formula is low residue and high cost.
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What are the CHO, pro, and fat components in elemental formulas
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CHO: mono/disaccharides Pro: amino acids, di/tripeptides fat: lower than polymeric; combo of medium and long chain fatty acids. MCTs are used as they are more water soluble and easier to absorb (absorbed directly into serum rather than lymph w/o chylomicron) |
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Describe continuous EN adminstration:
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EN formula is administered at a constant rate over 10 to 24 hours. May be done cyclically. Reduces the risk of gastric residuals, GERD, aspirations and diarrhea |
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Describe intermittent and bolus EN administration |
Intermittent administration is when the total amount is divided into three to six feedings and administered over thirty to sixty minutes. Bolus feeding mimics meals and is given through a syringe over ten to fifteen minutes. |
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name the steps in tube feeding (7)
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Select administration route, appropriate formula, assess energy/protein/micronutrient requirements, select formula, determine infusion rate and method, assess fluid intake relative to requirement, monitor and make changes as needed
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Why should the tube be flushed very four hours, before/after feeding, and after meds?
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To keep tubes from clogging
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List signs and symptoms of EN feeding intolerance.
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abdominal distension, nausea, vomiting, signs of aspiration (wheezing, coughing, SOB)
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List the four metabolic problems assocaited with EN
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Vitamin K Deficiency (abnormal gut flora/fat malabsorption), refeeding syndrome, hyperglycemia, fluid/electrolyte imbalances
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What is Parenteral Nutrition
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Nutrients are delivered directly into the bloodstream intravenously (arteries are too high pressure), without going through the GI tract and liver. There is no GI stimulation, as a result villi can flatten and other GI problems may occur.
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What is TPN
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Total parenteral nutrition - all nutrient needs are met through TPN, delivered into a large central vein with high blood flow
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What is PPN |
Peripheral parenteral nutrition - nutrition administered through a small, peripheral vein with low blood flow and only partially meets needs
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What is PICC
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Peripherally inserted central catheter - catheter is inserted through peripheral vein and threaded to the subclavian vein (done for TPN)
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What is the Peripheral Venous Route
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Catheter is placed in a small peripheral vein using venipuncture. This requires good peripheral vein access. Irritation frequently develops and peripheral vein access may be quickly exhausted
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Why is it difficult to meet nutritional needs with PPN
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Peripheral veins do not tolerate a hypertonic solution well and can be quickly irritated. Solutions with adequate electrolyte/carbohydrate levels are often very hypertonic.
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What are parenteral solutions
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Formulas for PN usually mixed by pharmacists in hospitals. Usually a standard base is used and then the formula is individualized to meet needs.
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Why is it challenging to incorporate some nutrients, such as calcium and phosphate, in an enteral solution
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They tend to precipitate out of solution and once that happens they cannot be used by tissues and cells. They may also clog the tubes.
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What are the CHO, Lipids and Pro used in EN
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CHO - mono/disaccharides AA - indispensable AA + enough to meet N needs Lipids - may be soy/safflower oil with glycerol and egg yolk or a balance of n-3, n-6 and n-9 PUFAs |
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Why are there typically more water soluble vitamins than recommended by DRIs in EN?
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The kidneys tend to excrete more when delivered quickly into serum therefore decreasing bioavailability of water soluble vitamins. There is also increased breakdown in processing, and transit
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Why are trace elements often not included in enteral solutions
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toxic levels can build up quickly so levels supplied by contamination are relied up on. I f necessary (on TPN long-term or deficiency is present) conservative doses may be given very infrequently
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Why is Fe often not added to TPN
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The need for Fe is much lower as much higher bioavailability (Fe is mainly lost in GIT). If Fe is needed, small amounts will be given periodically rather than adding it to TPN. Serum ferritin will be used as an indicator to determine if needs are being met.
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Why is free Fe bad?
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Pro-oxidant, increases infection risk
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What are the two types of formulas for PN?
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1 - 2 in 1 formulas: lipid and the rest are separate and connect just before entering the vein. This allows for more variability and less concerns about the impact on solubility 2 - 3 in 1 formulas: all components are mixed which is easier for nurses and can save on costs but this limits the electrolyte and AA content |
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Describe PN continous infusion
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PN is administered at a constant rate with an infusion pump. This is usually done by starting with a very low infusion rate and increasing to goal as tolerated.
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Describe PN cyclic infusion
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PN is administered for a set time at a set time. This is done to prepare patients to come of TPN or go home.
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What biochem measures should be used for someone on nutrition support therapy (10)
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serum electrolytes, creatinine, Mg, P, Ca, blood glucose, triglycerides, liver function, CBC, prothrombin time
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List the complications of EN
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sepsis, hyperglycemia, electrolyte/fluid imbalance, underfeeding, overfeeding, refeeding syndrome, gastrointestinal upset
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Describe the signs and symptoms of refeeding syndrom
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signs - severe fluid electrolyte shift (especially hypophosphatemia), impaired cardiac/neuromuscular/respiratory function, edema, cardiac arrhythmias, hemolysis symptoms - fatigue, lethargy, dizziness, muscle weakness |
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Why is overfeeding with nutrition support bad?
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It increases CO2 production which can make it difficult/prolong weaning from a respirator
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What is the effect of TPN on the GIT (4)
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decreased villi function, cholestasis (impaired bile release), increased serum liver enzymes (lead to hepatobiliary dysfunction and PN associated liver disease), and decreased pancreatic function and secretion
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How do you calculate mEq
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mEq = mmol/valence
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How do you calculate mmol
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mmol = mg/atomic weight
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Describe the ideal weight-loss drug
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causes weight loss, no side effects, weight loss is continued or maintained after drug discontinuation and patient has improved cholesterol, blood sugar, blood pressure, and overall decreased risk of health problems leading to death
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What tools are used to identify overweight/obesity
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BMI, waist circumference
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List six successful strategies for weight loss
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energy restriction (min intake 1200(f)/1500(m), fat restriction (<30%), fibre increase, physical activity (min 150 min/wk), behavioral/cognitive therapy, self monitoring
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Histone Methylation
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Gene silencer/suppressor - causes histones and DNA to tightly coil and prevents transcription
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Histone Acetylation
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Gene expresser - makes it possible for transcription to occur by uncoiling histones and DNA
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What is SNP
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single nucleotide polymorphism - a change in a gene caused by a single nucleotide change
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What is a polygenetic disorder? two examples
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Disorder caused by more than one gene. Chronic diseases such as diabetes (T2) and cancer are examples
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What is a monogenetic disorder? one example
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Disorder caused by one gene - for example PKU
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What is someone starving most likely to die from?
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Lung infection, general infection
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Describe the metabolic adaption to starvation:
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Once glycogen stores are depleted, insulin levels fall and adipose (lipolysis) begins to generate ketones. In order to preserve muscle, tissues adapt to use ketone bodies as the main energy source and bMR is decreased to conserve energy.
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What happens in response to injury?
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Pro-inflammatory cytokines increase sympathetic nervous system action and BMR increases, muscle breakdown increases, gluconeogenesis increases, insulin levels rise, insulin resistance increases, and glucose is the main energy source.
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What is the Ebb phase of injury?
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The period of hemodynamic instability and shock, marked by a decreased metabolic rate and falling body temp. Usually lasts 24 to 48 hours.
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What is the acute hypermetabolic response of the Flow phase of injruy?
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The hormonal response that causes hyperglycemia, increased gluconeogenesis, increased insulin levels and resistance, decreased lipolysis/ketogenesis and inceased mustle catabolism/decreased anabolism.
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What are the two phases of injury
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Ebb phase (1st), Flow phase (2nd) - acute hyper metabolic response and adaptation
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|
What is the adaptive response of the Flow phase of Injury
|
When the metabolism begins to return to normal as the injury subsides. Includes return to protein anabolism, normalizing hormone levels, normalizing glucose levels, nitrogen balance and decreasing RMR
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What is SIRS
|
Systemic Inflammatory Response Syndrome - A complication that can arise from metabolic stress characterized by increased WBC, heart rate and respiration. Fever/hypothermia, elevated acute phase proteins, and glucose are also seen. |
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What is MODS
|
Multiple Organ Dysfunction Syndrome - a life threatening complication when two or more organs experience altered function and homeostasis cannot be maintained without intervention.
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|
What is the gold standard for estimating energy needs during metabolic stress?
|
Indirect calorimetry (IC)
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|
What equation is considered the best for calculating RMR for critically ill patients?
|
Penn State University Equation - it is very dynamic
|
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|
What equation is used for critically ill not on a ventilator?
|
Mifflin St. Jeor with a stress factor of 1.25
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|
What is recommended to determine energy needs for those who are obese with metabolic stress?
|
IC is best, if not permissive underfeeding should be used as adjusted body weights have not been validated. 11-14 kcal/kg may be used
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|
What are the protein requirements for those undergoing stress? BMI<30 and >30.
|
1.2 - 2.0 g/kg and >2.5g/kg (with permissive underfeeding for obese) respectively
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|
What is the best nutrition therapy choice?
|
Enteral nutrition, PN should only be used when other options are infeasible, it has been seven days of poor intake (well nourished) or patients is malnourished and unable to be fed through other methods
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|
What are the functions of skin?
|
barrier (infection, waterloss), temperature regulator
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|
What is a partial thickness, superficial burn?
|
injury to the epidermis (outer, nonvascular layer) characterized by redness and edema.
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What is a partial thickness, deep dermal burn? |
Injury to the epidermis and a portion of the dermis (fibrous inner layer containing blood vessels, nerves, glands, hair roots). Epithelial regeneration is possible.
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What is the epidermis?
|
Outer skin layer containing no vasculature.
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What is the dermis?
|
The fibrous inner layer of the skin containing blood vessels, nerves, glands, and hair roots
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|
Full thickness burn?
|
The entire dermis and epidermis is destroyed and the subcutaneous fat, muscle, and even bone may be damaged. Eschar is all that remains, regeneration is not possible, and skin grafting is necessary.
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What is eschar?
|
The dry, leathery, inelastic slough composed of former skin elements after being burned.
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What is the preferred energy source by burns?
|
glucose
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What are the most reliable, non IC, ways of estimating energy needs for burn patients?
|
Ireton Jones and Curreri formulas are used but tend to over estimate burns. The Toronto Formula seems to be the best as it is dynamic and allows for daily adjustment.
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What are the key micronutrients for burns?
|
Vitamin A, ascorbic acid, zinc, antioxidants
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|
Define Atherosclerosis
|
The thickening of blood vessel walls and loss of vascular elasticity. A long process that involves the buildup of plaque in the arterial intima under the monolayer.
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What causes atherosclerosis
|
Stress (physical, chemical, ROS) causes inflammation and leukocytes migrate to the site. Oxidized LDL migrates with leukocytes into the intima where monocytes become macrophages and engulf them to form foam cells. Eventually this progresses into a lesion with a fibrous cap and a necrotic core.
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Describe thrombosis
|
something causes injury to a fatty streak, shifting the fibrous cap, exposing collagen and a thrombus (clot) forms.
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Define cardiovascular disease
|
a broad term that encompasses many diseases including CHD, metabolic syndrome, congestive heart failure, stroke, etc
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Define myocardial infarction
|
ischemia in the coronary arteries resulting in necrosis, tissue damage and potentially death
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Explain the two systems that control blood pressure
|
1. renin angiotensin - decreased blood flow is sensed as decreased fluid volume and the kidneys release renin which signals aldosterone to cause the kidneys to excrete less salt as a means of increasing blood volume and increasing pressure. 2. sympathetic NS - epinephrine and norepinephrine increase HR and cause arterial constriction which causes BP to rise |
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What does DASH stand for
|
Dietary approaches to stop hypertension - a diet plan that emphasizes fresh produce and other sources of healthy fibre and protein without specifically limiting sodium
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What is a myocardial infarction
|
heart attack due to blockage preventing circulation. may be in the form of angina or a stroke
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What are the symptoms of angina
|
chest pain/discomfort, discomfort in other areas (jaw, neck, shoulders, arms, back), shortness of breath, sweating, nausea, light headedness
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What is FAST
|
FAST is the acronym to remember for strokes F - face is it drooping? A - arms can you lift both? S - speech is it slurred? T - time call 911 right away |
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|
What are the 4 kinds of lipid lowering medications?
|
Statins, fibrates, bile acid resins, nicotinic acid
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What are statins
|
The first line drug therapy for lowering LDL. Work by blocking HMG CoA reductase. Interact with grapefruit (increases bioavailability)
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What are fibrates
|
Drugs used to lower triglycerides
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What are bile acid resins
|
Rarely used drug that acts by binding bile acids for excretion in feces and decreasing LDL as a result. Severe GI effects so rarely used.
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What is nicotinic acid used for
|
Raising HDL. Rarely used due to flushing effect.
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|
What are thiazide diuretics
|
A group of potassium depleting diuretics that increase sodium and water excretion decreasing blood volume while causing blood vessels to dilate. Used as an antihypertensive.
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What are beta adrenergic blockers
|
Used as an antihypertensive, they decrease heart rate and cardiac output as well as inhibit renin release (like an ACE inhibitor). Potassium sparing therefore should not be used with a potassium supplement
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What are angiotensin II receptor blockers
|
antihypertensive agent that blocks receptors, like an ACE inhibitor and should not be used with them or beta adrenergic blockers
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What is a calcium channel blocker used for
|
antihypertensive - lowers BP by dilating arterioles, reducing heart rate and cardiac output. Interacts with grapefruit (increases bioavailability)
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|
What are diuretics used for?
|
increase urinary excretion of Na and water to treat hypertension/congestive heart failure. May be potassium sparing (thiazide) or depleting (spironolactone)
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What is digitalis used for
|
To increase heart contraction strength, also slows heart rate and may be used to manage arrhythmias. Important interaction when combined with potassium depleting diuretics (thiazide)
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|
How do antiplatelet agents work?
|
Act as an anticoagulant by preventing platelet aggregation (blood thinner). Eg. Aspiin
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|
How does warfarin work?
|
Inhibits clotting factors by antagonizing vitamin K related production of clotting factors.
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|
What is the vitamin K AI
|
120 mcg (men), 90 mcg (women)
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|
What is the heart healthy fat recommendation?
|
20 to 25%
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|
|
What is the recommended sat fat level
|
<7%
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|
What is recommended for trans fats
|
limit to <1%
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|
What is the recommended sodium level
|
<2300 mg/day; <2g/day if HF
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|
What is congestive heart failure
|
Ventricle's ability to eject blood/fill with blood is compromised and blood begins to pool in venous circulation, and tissues do not receive adequate oxygenated blood. Many possible causes (MI, hypertension)
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|
What happens in all cases of heart failure
|
Damage to the heart/hypertension requires the heart to pump harder and a ventricle hypertrophies which decreases cardiac output. Blood begins to pool in venous circulation and oxygenated blood doesn't reach everywhere. The kidneys treat it like decreased volume and increase fluid and sodium retention. Then edema occurs due to increased hydrostatic pressure.
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|
What are the symptoms of heart failure (6
|
dyspnea (SOB), orthopnea (SOB when lying flat, fatigue, weakness, exercise intolerance, cold feeling
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|
What nutrition therapy is used for acute decompensated heart failure
|
diuretics and sodium and fluid restriction used to treat volume overload.
|
|
|
how is metabolic syndrome diagnosed?
|
3 or more of the following: - elevated BG - elevated TG - elevated BP - elevated waist circumference - reduced HDL |
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|
What does metabolic syndrome increase the risk of?
|
CHD, T2DM
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|
What is neoplastic disease
|
Cancer - a multifactorial disorder of cell growth and regulation
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|
What is the pathophysiology of Cancer
|
Initiation, promotion, progression to neoplasm
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|
What are oncogenes
|
Genes that exert effects on tumour growth by controlling cell division
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|
What are tumour suppressor genes?
|
Genes that cause apoptosis in tumour cells but lose function when mutation occurs.
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|
What is angiogenesis
|
The process by which tumour cells recruit blood vessels to support their metabolic needs
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|
What is metastasis
|
spread of cancer cells to distant sites
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|
What are malignant tumours
|
Have the properties to metastasise and are in the process of forming tumours in other sites
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|
What is the TNM cancer staging system
|
The Tumour node metastasis cancer staging system is commonly used to stage cancers. T - tumour size N - number of lymph nodes spread to M - presence of metastasis |
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|
What is cancer cachexia
|
wasting due to the complex metabolic state brought on by cancer
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|
What is dysguisia/ageusia
|
altertered taste
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|
|
What is dumping syndrome
|
abdominal discomfort with abdominal discomfort |
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|
What is neutropenia
|
Decreased WBCs resulting in immunosuppression
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|
|
What are the goals of nutrition therapy in cancer
|
minimize/reverse weight loss/muscle wasting, maintain nutrition status, minimize food rrelated discomfort
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|
|
What is a useful tool for assessing cancer patients?
|
Subjective global assessment (SGA)
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|
|
What can inflammation do to Fe
|
It decreases serum transferritin even when iron stores are high
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|
|
What is the protein requirement for cancer
|
1.2-2g/kg
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|
|
What is sarcopenia
|
Severe muscle wasting 2 or more SD from normal skeletal muscle stores
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|
|
What is a food allergy
|
An adverse reaction to food. May be IgE mediated, non-IgE mediated or mixed
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|
What is an immune mediated reaction
|
anaphylaxis, oral allergy syndrome
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|
What is a non IgE immune mediated reaction
|
enterocolitis
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|
|
examples of a mixed reaction
|
dermatitis, eosiniophilic esophagitis, eosinophilic gastroenteritis
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|
|
Examples of non immune mediated reaction
|
Intolerances - metabolic (lactose), pharmaceutical (caffeine), toxic, idiopathic
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|
What causes false positives (food allergy)
|
Skin mast cells don't degranulate like mast cells in the GI tract
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|
|
What causes farlse negatives (food allergy)
|
Commercial preparations of allergens may differ or be expired and not cause the reaction
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|
|
Describe the pathophysiology of an IgE mediated food reaction
|
After ingestion, immune cells become stimulated and produce IgE antibiodies specific to the food which binds to basophils and mast cells. At next ingestion, IgE specific antibodies bind and trigger the release of allergy mediators (histamine, etc) and cause symptoms
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|
|
Describe the pathophysiology of anaphylaxis
|
IgE mediated generalized degranulation of mast cells triggers an acute, potentially fatal systemic reaction that progresses to shock within minutes to hours. Exercise induced exists and can occur within two hours of eating.
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|
|
oral allergy syndrome (OAS)
|
associated with pollen induced rhinitis. Foods have cross reactivity between proteins and set off symptoms.
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|
|
Pathology of oral allergy syndrome
|
mast cells release IgE in response to allergen in raw food and release mediators.
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|
|
Eosinophilic Esophagitis - describe
|
An IgE non-IgE mixed reaction resulting in esophageal inflammation that leads to dysphagia, abnormal chest pain, poor appetite or regurgitation. Therapy is PPI (proton pump inhibitors) and nutrition therapy targeted to avoid problem foods
|
|
|
Name 3 indispensable branched chain amino acids and the site of metabolism
|
Valine, leucine, isoleucine - muscle
|
|
|
Name the three steps of BCAA metabolism and if they are reversible
|
1 - transamination (reversible) 2 - Oxidative decarboxylation to Acyl-CoA Thioesters (irreversible) 3 - dehydrogenation to alpha, beta unsaturated Acyl CoA Thioesters (Irreversible) |
|
|
Name the step in BCAA metabolism where an error causes maple syrup urine disease
|
Oxidative decarboxylation to AcylCoA Thioesters - cause buildup of alpha ketones and BCAA
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|
|
Name the step in BCAA metabolism where an error in metabolism causes isovaleric acidemia
|
Dehydrogenation to alpha, beta unsaturated Acyl CoA thioesters - results in buildup of leucine product (isovalerate) in blood
|
|
|
Name the step in BCAA metabolism where an error in metabolism causes propionic acidemia
|
Dehydrogenation to alpha, beta unsaturated Acyl CoA thioesters - results in buildup in propionyl coA or methylmalonyl coA metabolism and requires biotin supplementation
|
|
|
What is the treatment for propionic acidemia
|
VOMIT diet - limits propionogenic substances V - Valine O - odd chain fatty acids M - methionine I - isoleucie T - threonine |
|
|
What is maple syrup urine disease
|
An inherited group of disorders in BCAA metabolism resulting from mutations that impair branched chain ketoacid dehydrogenase (2nd step). Treatment is to avoid phenylalanine
|
|
|
Name the indispensable and conditionally indispensable aromatic amino acids
|
1 - phenylalanine 2 - tyrosine |
|
|
name the four metabolic disorders in aromatic amino acid metabolism
|
Tyrosiemia Type 1, and Type 2 (aka richner hanhart syndrome), Neonatal Tyrosinemia, Alkaptonuria (dark urine)
|
|
|
What is the general treatment for inborn errors of metabolism
|
Make dietary changes necessary to avoid problem amino acids.
|
|
|
What is CF
|
Cystic fibrosis - an inherited, recessive autosomal disease of exocrine glands characterized by thick mucus build up and secretions from epithelial surfaces.
|
|
|
What is the main protein affected by CF
|
CFTR - a channel in epithelial cells that functions to direct Cl, Na and fluid flow.
|
|
|
What is the pathophysiology of CF
|
CFTR's function ranges from compromised to absent. This has a significant impact on Cl flow which results in abnormal fluid excretion making epithelial secretions abnormally thick. In severe cases, the mucous is thick and builds up permanently. This can occur in the lungs, pancreas, liver, GIT, and skin.
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|
|
What are the respiratory symptoms of CF (4)
|
Coughing, wheezing, dyspnea, frequent lung infections
|
|
|
What are the GI symptoms of CF (4)
|
meconium ileus (bowel obstruction), abdominal distension, steatorrhea, foul smelling bulky stools
|
|
|
What are the sinus symptoms of CF (2)
|
nasal polyps, rhinitis
|
|
|
Other signs of CF (4)
|
Failure to thrive, poor weight gain, poor growth, salty skin
|
|
|
What test is the gold standard for CF diagnosis
|
Sweat chloride test
|
|
|
What micronutrients should be supplemented in CF patients?
|
Fat soluble vitamins (ADEK)
|
|
|
What micronutrients should be closely monitored in CF patients (6)
|
sodium, calcium, phosphorus, magnesium, iron, and zinc
|
|
|
Define COPD
|
Chronic obstructive pulmonary disease - a progressive condition that is the result of irreversible damage to bronchioles and pulmonary capillary beds.
|
|
|
What does COPD do?
|
limit exhalation (pink puffers) - amount of air in lungs increases but exhalations do not increase
|
|
|
What has lean muscle mass loss been assocaited with in COPD
|
decreased diaphragm strength (decreased expiratory capacity), worsening symptoms, and decreased quality of life.
|
|
|
Define hypoxia
|
A condition of low blood oxygen levels - often treated with oxygen.
|
|
|
Why is nutrition so important in COPD?
|
malnutrition and weight loss is associated with increased infection, disease progression and decreased quality of life.
|
|
|
What is the MRC dyspnea scale?
|
Used in COPD to grade severity of COPD disability - ranges from grade 1 (none) to 5 (severe)
|
|
|
What is the CTS Classificaiton of COPD
|
A system that classifies COPD severity
|
|
|
What is the adjusted body weight formula
|
(current body weight - ideal body weight)*0.25
|
|
|
Name two sources of potassium
|
bananas, potatoes
|
|
|
name four phosphorus sources
|
dark pop, meat, high fibre products, dairy
|
|
|
How to calculate g of high biological value protein in meat
|
(#Oz x 0.5)/7g
|
|
|
List common nutrition issues after a kidney transplant
|
CHO intolerance, increased postop protein catabolism, increased drug nutrient interactions, obesity, hyperlipidemia, hyperkalemia, and calcium/phosphorus issues
|
|
|
Why are protein needs increased during dialysis?
|
dialysis results in some protein loss and accelerates protein catabolism
|
|
|
Why are dietary restrictions put on patients with stage 5 chronic kidney disease
|
Kidney is unable to excrete waste and fluid effectively and excess needs to be minimized in order to minimize buildup and keep the patient feeling well
|
|
|
What supplements should be taken/avoided in CKD
|
Take - water soluble multi, Fe Avoid - Vitamin A, Ca |
|
|
Why does potassium only need to be limited in late stages of CKD
|
Distal tubes have a large capacity to secrete K therefore its ability to moderate potassium levels lasts until the later stages
|
|
|
Why is fluid restricted in late stage CKD
|
Na and Fluids are retained at a higher rate. Fluids may not need to be consciously restricted as thirst often decreases with Na intake decreases
|
|
|
How can Na and fluid be monitored in CKD
|
Edema, serum Na, urine volume, blood pressure, body weight
|
|
|
Why does Na restriction not become critical until later stages
|
As GFR falls, Na balance is initially maintained by nephron compensation. In later stages, the nephrons can no longer keep up and Na is largely retained, as are fluids which can result in hyponatremia/over hydration.
|
|
|
What are the energy needs for CKD?
|
35kcal/kg - decreases with age due to RMR decreases. It is important to adjust PRN as protein energy malnutrition can be a major issue
|
|
|
What is the uremia?
|
Uremia is the result of waste products normally excreted in urine not being excreted. It can be increased by inadequate energy intake (increased pro catabolism), inadequate protein intake, or unbalanced protein intake.
|
|
|
What is the viscous cycle of uremia?
|
uremia => anorexia/nausea/fatigue => decreased intake => muscle catabolism => increased uremia
|
|
|
How do protein needs change as CKD progresses?
|
In the early stages, protein needs stay relatively near normal (0.8-1.0g/kg) and decrease in the stage prior to dialysis as the kidneys can no longer keep up with higher intake. Once dialysis begins, protein needs increase (1.2g/kg) as dialysis accelerates protein catabolism and results in some protein loss.
|
|
|
Why are Ca based Phosphorus binders recommended for chronic kidney disease?
|
elevated phosphorus that the kidneys cannot keep up with results in Ca levels falling, which increases PTH levels and results in CaPO4 being removed from bone which further elevates Phosphorus levels exacerbating the issue and furthering bone loss.
|
|
|
Why is anemia common in CKD
|
Kidney problems decrease erythropoietin production. Erythropoietin is needed for RBC production. Plus dialysis and biochem tests
|
|
|
What is used to treat anemia in CKD
|
Human Recombinant Erythropoietin and Fe
|
|
|
Why are active vitamin D analogues given in CKD
|
Kidneys decreased function prevents it from converting vitamin D into its active form 1,25(OH)D by hydroxylation of the 1st position. This can result in a calcium deficiency.
|
|
|
Continuous ambulatory vs. cycling paritoneal dialysis
|
Ambulatory (CAPD) - dialysate stays in the peritoneal space for four to six hours then is drained and repeated with a longer dwell period during sleep. cycling (CCPD) - dialysate is cycled by a machine during sleep, and left to dwell during the day |
|
|
Why is glucose in dialysate
|
In peritoneal glucose is used to make the dialysate hypertonic and allow for fluid drainage and prevent hypoglycemia. In hemodialysis glucose is typically used more to prevent hypoglycemia.
|
|
|
How is access obtained in hemodialysis
|
Entry is through an artery in an arm/leg and blood is returned into the parallel vein. Access is created surgically with a fistula or graft.
|
|
|
What is the pathophysiology of CKD
|
Gradual decrease in the number of functioning nephrons. As the number of nephrons decline, the functioning nephrons compensate and for a while can keep up. Progressively function is lost until a transplant or dialysis is required.
|
|
|
What are possible etiologies of Acute Renal Failure?
|
Severe dehydration, toxicity, obstruction, infection, decreased blood flow
|
|
|
What equations are used to calculate eGFR and what do they take into account?
|
Cockcroft-Gault equation, MDRD - age, sex, body size
|
|
|
What is used to measure GFR
|
eGFR and serum creatinine
|
|
|
What influences serum creatinine
|
Muscle mass - phosphocreatine is the main energy source for muscles
|
|
|
Where does the kidney absorb/resorb K
|
Proximal Tube - Majority of K is resorbed from filtrate Distal Tube - remaining K is resorbed in exchange for Na |
|
|
Where does the kideny absorb/resorb Na
|
Proximal tube - unregulated basal Na resorbtion Distal tube - Na resorption/secretion is regulated by aldosterone (increases Na excretion |
|
|
How is fluid balance regulated |
The kidney conserves/excretes fluids as needed. When the hypothalamus notices decreased fluid volume it signals antidiuretic hormone release (posterior pituitary) increasing water reabsorption (concentrating urine).
|
|
|
What is the functional unit of the kidney
|
Nephron
|
|
|
What is the glomerulus
|
The part of the kidney that filters molecules in bowman's capsule
|
|
|
What are tubules
|
The site of reabsorption and excretion in the kidneys into urine.
|
|
|
What are the 3 processes in urine formation
|
Filtration (glomerulus), tubular reabsorption, tubular secretion
|
|
|
What is physiological pH
|
Although pH varies throughout the body, physiological pH (serum) is defined as being between 7.35 and 7.45
|
|
|
What is the pH of serum in alkalosis
|
pH>7.45
|
|
|
What is the pH of serum in acidosis
|
pH<7.35
|
|
|
What do acids do?
|
Acids donate/give up H+ ions
|
|
|
What is carbonic acid
|
Carbonic acid is the form that CO2 takes in blood. H2CO3. It is a volatile acid that can be converted into gas form and be excreted by the lungs.
|
|
|
What are non-volatile/fixed acids?
|
Products of CHO, lipid, and mainly protein metabolism that cannot be excreted by the lungs. They are dealt with by the kidney (buffer)
|
|
|
What do bases do?
|
Accept/receive H+ ions
|
|
|
What is the carbonic acid/CO2 process
|
Protein breakdown + bicarbonate ====> ====> carbonic acid ===== > CO2 + H2O (lungs) |
|
|
How does the respiratory system respond to acidosis/alkalosis
|
acidosis: Respiratory rate increases to decrease CO2 levels which increases pH alkalosis: Respiratory rate drops to increase CO2 levels which decreases pH CO2 (CO2 + H2O <=> H2CO3 <=> H + HCO3) |
|
|
How does the renal system respond to acidosis/alkalosis
|
Acidosis: The kidneys increase H+ excretion and secretion (increasing urinary H+), Increase HCO3 reabsorption and addition to plasma, acidic urine Alkalosis: Decreases H+ excretion and secretion (making urine more basic), Increase HCO3 secretion and excretion and decreases reabsorption |
|
|
define hypercapnea
|
Excess CO2 in blood (causes respiratory acidosis if pH<7.35)
|
|
|
What is respiratory acidosis
|
Serum pH falls below 7.35 due to excess CO2 in the blood
|
|
|
What causes respiratory acidosis
|
Anything that suppresses pulmonary function (decreasing CO2 excretion) - hypoventilation, COPD, severe ammonia build up/asthma, excess CO2 production (excess CHO/energy intake)
|
|
|
How is respiratory acidosis treated
|
Ways of correcting the underlying problem. Typically increasing ventilation/oxygenation
|
|
|
What is respiratory alkalosis
|
Excess of base relative to CO2 production
|
|
|
What causes respiratory alkalosis
|
Anything that causes hypoxia (hyperventilation, shift of acid from ICF to ECF (eg. H2CO3 moves into cells in exchange for Cl), asthma, altitude change, drugs, anxiety, fever, sepsis
|
|
|
What are the signs of respiratory alkalosis
|
Low partial pressure of CO2 (acute), low plasma HCO3 (chronic)
|
|
|
What are the symptoms of respiratory alkalosis
|
cardiac, CNS, respiratory (rate decreases)
|
|
|
What is metabolic acidosis
|
Less base relative to CO2
|
|
|
What causes metabolic acidosis
|
Excessive bicarbonate (HCO3) loss - often due to diarrhea, ketoacidosis, kidney/system loss of HCO3
|
|
|
How is Metabolic acidosis treated?
|
Raise pH to a safe level with IV HCO3 slowly
|
|
|
What is metabolic alkalosis
|
Excess HCO3
|
|
|
What causes metabolic alkalosis
|
Fluid imbalance - fluid volume doesn't chance, diarrhea, vomiting, potassium depleting diuretics, IV, blood transfusion, chronic/excess antacid use
|
|
|
How is metabolic alkalosis treated
|
Isotonic saline with KCl to treat the underlying condition
|
