Chatgbt Flashcards
What defines peripheral venous access?
Tip terminates outside of central vasculature
What is the max osmolarity for peripheral parenteral nutrition (PPN)?
<900 mOsm/L
What are disadvantages of PPN?
Short-term use, risk of phlebitis, limited calorie delivery
What is a single-lumen catheter?
One channel for infusion
What is a double-lumen catheter?
Two channels—can infuse different solutions simultaneously
What is a triple-lumen catheter?
Three channels—used in critical care or multiple infusions
Why are multiple lumens helpful?
Separate administration of incompatible medications/nutrition
What is a nasogastric (NG) tube?
Inserted through the nose into the stomach—short-term use
What is a nasojejunal (NJ) tube?
Inserted through the nose into the jejunum—post-pyloric feeding
What is a gastrostomy (G-tube)?
Tube placed directly into the stomach—long-term EN
What is a jejunostomy (J-tube)?
Tube placed directly into the jejunum—used if stomach not functional
What is a PEG tube?
Percutaneous endoscopic gastrostomy—G-tube placed via endoscopy
What is a PEJ tube?
Percutaneous endoscopic jejunostomy—J-tube placed via endoscopy
What is the difference between balloon vs. non-balloon G-tube?
Balloon: easier at-home replacement; Non-balloon: more secure
What is a low-profile G-tube?
Flush with skin, used for active patients
How is enteral tube patency maintained?
Flush with water before/after feeding or medication
What is a common cause of tube occlusion?
Medication residue, inadequate flushing
How can clogged tubes be cleared?
Warm water flushes, enzyme-based unclogging kits (no soda or juice)
What is a drug-nutrient interaction?
A reaction between a drug and a nutrient that affects absorption, metabolism, or excretion of either
What is the interaction between phenytoin and EN?
EN decreases phenytoin absorption
How to manage phenytoin interaction with EN?
Hold tube feeds 1–2 hours before and after dosing
How does warfarin interact with nutrition?
Vitamin K intake can reduce warfarin effectiveness
How to manage warfarin interaction?
Maintain consistent vitamin K intake
What nutrient deficiencies can PPIs cause?
Vitamin B12, magnesium, calcium
What are nutrition concerns with corticosteroids?
Hyperglycemia, increased protein breakdown, bone loss
What are nutrient losses associated with loop diuretics?
Potassium, magnesium, calcium, thiamine
What is a key nutritional concern with thiazide diuretics?
Hypercalcemia and potassium loss
What nutrient interactions occur with cholestyramine?
Decreases absorption of fat-soluble vitamins (A, D, E, K)
What is a common nutrient concern with prolonged antibiotic use?
Vitamin K deficiency and altered gut microbiota
What decreases iron absorption?
Calcium, PPIs, antacids, tannins (tea/coffee)
What enhances iron absorption?
Vitamin C and acidic environment
What nutrient should be supplemented with methotrexate?
Folic acid
What nutrient competes with levodopa for absorption?
Protein—high protein meals can reduce drug effectiveness
What drug is lipid-based and contributes calories?
Propofol (1.1 kcal/mL)
What vitamins are light-sensitive and degrade in TPN?
Vitamins A, C, and B1 (thiamine)
What trace element should be monitored in patients on long-term PPI or H2RA therapy?
Magnesium
What are the indications for enteral nutrition (EN)?
Functioning GI tract, unable to meet needs orally for >2–3 days
When should EN be initiated in critically ill patients?
Within 24–48 hours of ICU admission
What are contraindications to EN?
Non-functioning GI tract, bowel obstruction, hemodynamic instability
What are common routes for EN?
Nasogastric, nasojejunal, gastrostomy, jejunostomy
What is the difference between gastric and post-pyloric feeding?
Gastric: easier placement, higher aspiration risk; Post-pyloric: lower aspiration risk, for high reflux/vomiting
What are polymeric formulas?
Standard EN formulas with intact protein, fat, and carbohydrates
What are elemental/semi-elemental formulas?
Formulas with hydrolyzed proteins, for malabsorption or GI dysfunction
What is a modular formula?
Customizable formula components (e.g., protein powder, glucose polymers)
What is the recommended protein intake in EN for critically ill adults?
1.2–2.0 g/kg/day
What is the typical goal for EN advancement?
Reach goal rate within 48–72 hours if tolerated
What are signs of EN intolerance?
High gastric residuals, abdominal distension, vomiting, diarrhea
What is refeeding syndrome?
Fluid and electrolyte shifts (↓phos, K, Mg) when feeding is initiated after starvation
How can refeeding syndrome be prevented?
Start low and go slow, supplement electrolytes, monitor labs closely
How should medications be given via feeding tube?
Use liquid forms or crushable tablets, flush before/after administration
Which drugs interact with tube feeds?
Phenytoin, warfarin, fluoroquinolones—require holding feeds before/after
What is the difference between open vs. closed EN systems?
Open: decanted, increased contamination risk; Closed: prefilled, safer, longer hang time
What is the typical hang time for open EN systems?
4–8 hours
What is the typical hang time for closed EN systems?
Up to 24–48 hours
How much free water is in most standard EN formulas?
About 80%
What is the typical calorie density of standard EN formulas?
1.0–1.2 kcal/mL
What calorie density is considered energy-dense?
≥1.5 kcal/mL, used for fluid restriction
What is the typical fluid requirement for adults?
30–35 mL/kg/day
What is the Holliday-Segar method for pediatric fluid needs?
100 mL/kg for first 10 kg + 50 mL/kg for next 10 kg + 20 mL/kg for weight >20 kg
What are signs of fluid overload?
Edema, hypertension, pulmonary congestion
What are signs of dehydration?
Hypotension, tachycardia, decreased urine output, elevated BUN/Cr
Normal serum sodium range?
135–145 mEq/L
What does hyponatremia indicate?
Fluid overload, SIADH, renal failure
What does hypernatremia indicate?
Dehydration, diabetes insipidus
Normal serum potassium range?
3.5–5.0 mEq/L
Causes of hypokalemia?
Diuretics, GI losses, refeeding syndrome
Causes of hyperkalemia?
Renal failure, acidosis, tissue breakdown
Normal serum calcium range?
8.5–10.5 mg/dL
What should you check in hypoalbuminemia?
Corrected calcium
Corrected calcium formula?
Measured Ca + 0.8 × (4 - serum albumin)
Causes of hypocalcemia?
Vitamin D deficiency, pancreatitis, low magnesium
Causes of hypercalcemia?
Hyperparathyroidism, malignancy
Normal serum phosphorus range?
2.5–4.5 mg/dL
Causes of hypophosphatemia?
Refeeding syndrome, TPN without phosphorus, DKA
Causes of hyperphosphatemia?
Renal failure, tumor lysis syndrome
Normal serum magnesium range?
1.5–2.5 mg/dL
Causes of hypomagnesemia?
Diarrhea, alcoholism, diuretics
Causes of hypermagnesemia?
Renal failure, excessive supplementation
What is metabolic acidosis?
Low pH, low HCO3; causes: diarrhea, renal failure, ketoacidosis
What is metabolic alkalosis?
High pH, high HCO3; causes: vomiting, diuretics
What is respiratory acidosis?
Low pH, high CO2; causes: hypoventilation, COPD
What is respiratory alkalosis?
High pH, low CO2; causes: hyperventilation, anxiety
Where does most nutrient absorption occur?
Small intestine (primarily jejunum)
What is the function of the ileum?
Absorbs bile salts, vitamin B12, and some water/electrolytes
What is the role of the colon in digestion?
Absorbs water, electrolytes, short-chain fatty acids
What is the function of the pancreas in digestion?
Secretes enzymes for digestion of protein, fat, and carbohydrates
Where is intrinsic factor produced and what is its role?
Stomach; binds to vitamin B12 for absorption in the ileum
What is short bowel syndrome (SBS)?
Malabsorption from significant loss of small bowel surface area
What are nutrition concerns in SBS?
Fluid/electrolyte imbalance, fat malabsorption, nutrient deficiencies
Which part of the bowel can adapt best after resection?
Jejunum
Which part is most difficult to compensate for if resected?
Ileum
What is the role of the colon in patients with SBS?
Colon helps absorb fluids, SCFAs—important if ileum resected
What is small intestinal bacterial overgrowth (SIBO)?
Excessive bacteria in small bowel causing bloating, diarrhea, malabsorption
Risk factors for SIBO?
Stasis, strictures, blind loops, motility disorders
What is the role of bile salts?
Emulsify fats for digestion and absorption
What happens when bile salts are malabsorbed?
Fat malabsorption, steatorrhea, loss of fat-soluble vitamins
What is the concern with pancreatic insufficiency?
Inadequate digestion of fat/protein, leading to steatorrhea and malnutrition
How is pancreatic insufficiency managed?
Pancreatic enzyme replacement therapy (PERT) with meals/snacks
What is a chyle leak?
Loss of lymphatic fluid rich in fat/protein/electrolytes
How is a chyle leak managed nutritionally?
Low-fat or MCT-based diet; may require EN or PN
What is bile acid diarrhea?
Occurs after ileal resection; bile salts enter colon causing fluid secretion
Treatment for bile acid diarrhea?
Bile acid sequestrants (e.g., cholestyramine)
What is an anastomosis?
Surgical connection between two parts of the bowel
What is a fistula?
Abnormal connection between bowel and another surface or organ
What is high-output fistula defined as?
> 500 mL/day output
Normal fasting glucose range?
70–99 mg/dL
What is hyperglycemia defined as?
> 180 mg/dL
What is hypoglycemia defined as?
<70 mg/dL
Normal sodium range?
135–145 mEq/L
Normal potassium range?
3.5–5.0 mEq/L
Normal chloride range?
98–106 mEq/L
Normal CO2 (bicarb) range?
22–28 mEq/L
Normal calcium range?
8.5–10.5 mg/dL
Normal magnesium range?
1.5–2.5 mg/dL
Normal phosphorus range?
2.5–4.5 mg/dL
What does elevated AST/ALT suggest?
Hepatocellular injury
What does elevated ALP and bilirubin suggest?
Cholestasis or bile duct obstruction
What does elevated direct bilirubin indicate?
Obstructive or hepatocellular jaundice
What is prealbumin used to assess?
Short-term changes in nutrition status
Why is prealbumin not reliable in critically ill patients?
It is a negative acute-phase reactant
What is CRP used for?
Marker of inflammation
What does a high CRP indicate?
Acute inflammation, infection, or trauma
What does elevated BUN/creatinine indicate?
Dehydration or renal dysfunction
What does a high BUN:Cr ratio suggest?
Pre-renal azotemia (often due to dehydration)
What is a normal BUN:Cr ratio?
10:1 to 20:1
What lab reflects iron storage?
Ferritin
What lab reflects recent iron status?
Serum iron, transferrin saturation
What labs suggest iron deficiency anemia?
Low Hgb, low Hct, low ferritin, high TIBC
What lab is used to assess vitamin D status?
25(OH)D
What lab decreases in zinc deficiency?
Alkaline phosphatase
What labs are monitored for refeeding syndrome?
Phosphorus, potassium, magnesium
What does elevated ammonia indicate?
Liver failure, especially in hepatic encephalopathy
What does an RQ >1.0 suggest?
Overfeeding, lipogenesis
How many kcal/gram does dextrose provide in PN?
3.4 kcal/gram
How many kcal/gram does protein provide in EN/PN?
4 kcal/gram
How many kcal/gram does lipid provide in PN?
10 kcal/gram (from 20% lipid emulsion)
How many kcal/gram does lipid provide in EN?
9 kcal/gram
What is the typical non-protein calorie to nitrogen ratio (NPC:N) in PN?
100–150:1
What is the purpose of the NPC:N ratio?
To ensure adequate calories to spare protein for tissue repair and growth
How many grams of nitrogen are in 1 gram of protein?
1 gram of nitrogen = 6.25 grams of protein
What macronutrient has the highest respiratory quotient (RQ)?
Carbohydrates (RQ ~1.0)
What macronutrient has the lowest respiratory quotient (RQ)?
Fat (RQ ~0.7)
What is the typical protein range in PN for a critically ill adult?
1.2–2.0 g/kg/day
What is the minimum amount of carbohydrate needed to prevent ketosis?
100–150 g/day
What is a concern with excessive carbohydrate intake in PN?
Hyperglycemia, increased CO2 production, hepatic steatosis
What is a concern with excessive fat intake in PN?
Hypertriglyceridemia, impaired immune function
What are the components of TPN macronutrients?
Dextrose, amino acids, lipids
What are the phases of metabolic response to stress?
Ebb phase and Flow phase
What occurs during the ebb phase?
Hypovolemia, decreased metabolic rate, reduced tissue perfusion
What occurs during the flow phase?
Hypermetabolism, increased energy expenditure, catabolism, increased glucose production
What hormones increase during stress?
Cortisol, catecholamines (epinephrine/norepinephrine), glucagon
What are the consequences of prolonged stress response?
Muscle wasting, insulin resistance, negative nitrogen balance
What is gluconeogenesis?
Formation of glucose from non-carbohydrate sources like amino acids
What is lipolysis?
Breakdown of fat stores to free fatty acids and glycerol
What is proteolysis?
Breakdown of muscle protein into amino acids
What is the preferred fuel source in stress and sepsis?
Glucose
What is insulin resistance?
Decreased cellular response to insulin, common in critical illness
What metabolic changes occur during sepsis?
Increased glucose and lactate, altered protein metabolism
How does starvation differ from stress metabolism?
Starvation leads to fat adaptation and protein sparing; stress causes protein catabolism
What is the respiratory quotient (RQ) for carbohydrate metabolism?
1
What is the RQ for fat metabolism?
0.7
What RQ suggests overfeeding?
> 1.0
What is nitrogen balance and what does a negative balance indicate?
Difference between nitrogen intake and loss; negative balance indicates catabolism
How do you calculate nitrogen balance?
Nitrogen in (g protein/6.25) – (UUN + 4)
What condition increases nitrogen losses?
Burns, trauma, sepsis, wounds
What is the goal of nutrition in the critically ill?
Prevent further loss of lean body mass, support immune function, promote healing
What is the function of iron?
Oxygen transport via hemoglobin and myoglobin
What are symptoms of iron deficiency?
Microcytic anemia, fatigue, pallor
What are causes of iron toxicity?
Hemochromatosis, iron overload from transfusions
Which populations are at risk for iron deficiency?
Infants, menstruating women, GI bleed patients
Which nutrients/meds interfere with iron absorption?
Calcium, tannins, PPIs
What is the function of zinc?
Wound healing, immune function, taste perception
What are symptoms of zinc deficiency?
Poor wound healing, alopecia, dermatitis, taste changes
Who is at risk for zinc deficiency?
Burn patients, diarrhea, TPN without zinc
What inhibits zinc absorption?
High phytate intake, high calcium/iron
What is the function of copper?
Iron metabolism, antioxidant activity
Symptoms of copper deficiency?
Microcytic anemia, neutropenia, myelopathy
Who is at risk for copper deficiency?
Gastric bypass, high zinc intake, long-term PN
Function of selenium?
Antioxidant (glutathione peroxidase), thyroid function
Symptoms of selenium deficiency?
Cardiomyopathy, muscle weakness, immune dysfunction
Who is at risk for selenium deficiency?
TPN without selenium, GI surgery
Function of manganese?
Cofactor for enzymes, bone formation
Toxicity risk for manganese?
Cholestatic liver disease—can cause neurotoxicity
Function of chromium?
Enhances insulin action
Symptoms of chromium deficiency?
Glucose intolerance, neuropathy
Who is at risk for chromium deficiency?
Long-term PN without chromium
Function of iodine?
Thyroid hormone synthesis
Symptoms of iodine deficiency?
Goiter, hypothyroidism
Toxicity of iodine?
Thyroid dysfunction
Function of fluoride?
Dental and bone health
Toxicity of fluoride?
Dental fluorosis, GI upset
Function of molybdenum?
Cofactor in amino acid metabolism
Deficiency symptoms?
Rare—tachycardia, headache, neurologic issues
What are the six ASPEN malnutrition assessment characteristics?
Energy intake, weight loss, body fat loss, muscle loss, fluid accumulation, functional status
How many criteria are needed to diagnose malnutrition per ASPEN?
At least 2 of the 6
What defines severe malnutrition (chronic)?
> 5% weight loss in 1 month or >10% in 6 months with minimal intake for >1 month
What is functional status typically assessed with?
Handgrip strength
What does SGA stand for?
Subjective Global Assessment
What are the components of SGA?
Weight change, dietary intake, GI symptoms, functional capacity, physical exam (fat/muscle loss, edema)
What are the SGA classifications?
A: well nourished, B: moderately malnourished, C: severely malnourished
What is the NUTRIC score used for?
Assessing nutrition risk in critically ill patients
What factors are included in NUTRIC?
Age, APACHE II, SOFA score, number of comorbidities, days from hospital to ICU
What does a high NUTRIC score indicate?
Greater risk of adverse outcomes, more likely to benefit from nutrition intervention
What is MUST?
Malnutrition Universal Screening Tool—used in community and outpatient settings
What is the MST?
Malnutrition Screening Tool—quick, uses weight loss and appetite
What is the MNA?
Mini Nutritional Assessment—used for elderly patients
What does %IBW =?
(Current weight / Ideal body weight) × 100
What does %UBW =?
(Current weight / Usual body weight) × 100
What does weight loss % =?
((Usual weight – current weight) / usual weight) × 100
What is considered significant weight loss?
> 5% in 1 month or >10% in 6 months
What is BMI =?
Weight (kg) / height (m)^2
What BMI is considered underweight?
<18.5 kg/m²
What BMI range is normal?
18.5–24.9 kg/m²
What are indications for parenteral nutrition (PN)?
Non-functioning GI tract, failed EN trial, bowel obstruction, severe malabsorption
When should PN be initiated in critically ill adults?
If EN is not feasible after 7 days (or earlier in malnourished patients)
What is the difference between central and peripheral PN?
Central PN allows higher osmolarity solutions; peripheral PN is limited to <900 mOsm/L
What are typical macronutrient components of PN?
Dextrose, amino acids, IV lipids
What is the max recommended glucose infusion rate (GIR)?
<4–5 mg/kg/min in adults
What is a typical lipid dosing range for PN?
0.5–1.5 g/kg/day
What is the caloric value of 20% lipid emulsion?
2 kcal/mL (10 kcal/g)
What is a concern with excessive lipid administration?
Hypertriglyceridemia, impaired immune function
What are signs of essential fatty acid deficiency?
Dry, scaly skin; alopecia; impaired wound healing
How often should lipids be given to prevent EFAD?
At least 100 g/week (2–3 times/week)
What is SMOF lipid?
Soybean oil, MCT, olive oil, fish oil mix—less pro-inflammatory
What is cyclic PN?
PN administered over <24 hours (typically 12–18 hrs/day)
What are benefits of cyclic PN?
Improved liver function, mimics normal metabolism, mobility
What are risks of starting PN too quickly?
Refeeding syndrome, hyperglycemia, electrolyte shifts
What labs should be monitored closely during PN?
Glucose, electrolytes, triglycerides, liver function tests
What are signs of PN-associated liver disease?
Elevated LFTs, cholestasis, steatosis, fibrosis
What strategies help prevent PN-associated liver disease?
Cycle PN, avoid overfeeding, use trophic EN, lipid minimization
What is the role of acetate in PN?
Converted to bicarbonate—used to manage metabolic acidosis
What is the role of chloride in PN?
Used to manage metabolic alkalosis
What are common PN complications?
Infection (catheter-related), liver dysfunction, metabolic disturbances
What is the recommended protein intake in PN for critically ill adults?
1.2–2.0 g/kg/day
What is the max osmolarity for peripheral PN?
<900 mOsm/L
How is PN osmolarity calculated?
Based on dextrose, amino acids, electrolytes—lipids don’t contribute
What organization develops nutrition support guidelines?
ASPEN (American Society for Parenteral and Enteral Nutrition)
What are ASPEN’s recommendations for initiating EN in the ICU?
Within 24–48 hours of admission if hemodynamically stable
What is the ASPEN recommendation for protein in critically ill adults?
1.2–2.0 g/kg/day
What is ASPEN’s stance on glutamine in critical illness?
Not recommended for routine use in critically ill patients
What is the FDA limit for aluminum in PN solutions?
<25 mcg/L
What must manufacturers label on PN additives per FDA?
Maximum aluminum content at expiry
What labeling standards apply to EN products?
Must list nutrient content per serving and per mL
What is a DRG?
Diagnosis-Related Group—used for hospital reimbursement
What is the role of ICD-10 codes?
Diagnosis classification used for billing and documentation
What does CPT stand for?
Current Procedural Terminology—used for procedure coding
What documentation supports nutrition reimbursement?
Nutrition diagnosis, care plan, progress notes, justification for EN/PN
What is a root cause analysis (RCA)?
Structured method for identifying underlying causes of an event
What is a PDSA cycle?
Plan-Do-Study-Act—used in QI to test and implement changes
What do JCAHO and CMS require for nutrition?
Nutrition screening within 24 hours of hospital admission
What is the purpose of a nutrition care process (NCP)?
Standardized approach to nutrition assessment and care
What is the USP <797> guideline?
Standards for sterile compounding of parenteral nutrition
What is the Hang Time recommendation for open EN systems?
4–8 hours
What is the Hang Time recommendation for closed EN systems?
Up to 24–48 hours
What are key nutrition concerns in neonates?
Immature GI function, high energy/protein needs, fluid/electrolyte sensitivity
What trace elements are typically excluded in neonatal PN?
Manganese, chromium (risk of toxicity)
What is the typical GIR range for neonates?
4–12 mg/kg/min
How is fluid calculated for neonates?
Based on weight and age in mL/kg/day
What are key nutrition goals in AKI?
Avoid overfeeding, manage electrolytes, adequate protein (1.5–2.0 g/kg if on CRRT)
What electrolytes need close monitoring in CKD/AKI?
Potassium, phosphorus, magnesium
What type of formula may be needed in renal disease?
Low electrolyte, fluid-restricted, higher calorie density
What are nutrition concerns in liver disease?
Malnutrition, fat malabsorption, ascites, electrolyte imbalances
What is the preferred type of protein in hepatic encephalopathy?
Vegetable or BCAA-rich protein
What formula adjustments may be needed in liver failure?
Energy-dense, low sodium, moderate protein
What lab indicates impaired ammonia metabolism?
Elevated serum ammonia
What is cancer cachexia?
Metabolic syndrome with weight loss, muscle wasting, inflammation
What are nutrition goals in oncology?
Maintain weight, support immune function, prevent muscle loss
When is EN preferred in oncology?
When the GI tract is functional and oral intake is inadequate
What is the nutrition focus in Crohn’s disease?
Manage flares with low-residue diet, maintain nutrient adequacy
What deficiencies are common in IBD?
Iron, B12, vitamin D, calcium
What EN formula is often used in pancreatitis?
Elemental or semi-elemental, low-fat, jejunal feeding
What are nutrition considerations in obesity during critical illness?
Use adjusted body weight for energy/protein needs
What protein range is used in critically ill obese patients?
2.0–2.5 g/kg IBW/day
What are increased needs in burn patients?
High protein (up to 2.5–3 g/kg), high calorie, fluid/electrolyte repletion
What vitamins and minerals are important in burn recovery?
Vitamin C, zinc, selenium, vitamin A
What are the phases of metabolic response to stress?
Ebb phase and Flow phase
What occurs during the ebb phase?
Hypovolemia, decreased metabolic rate, reduced tissue perfusion
What occurs during the flow phase?
Hypermetabolism, increased energy expenditure, catabolism, increased glucose production
What hormones increase during stress?
Cortisol, catecholamines (epinephrine/norepinephrine), glucagon
What are the consequences of prolonged stress response?
Muscle wasting, insulin resistance, negative nitrogen balance
What is gluconeogenesis?
Formation of glucose from non-carbohydrate sources like amino acids
What is lipolysis?
Breakdown of fat stores to free fatty acids and glycerol
What is proteolysis?
Breakdown of muscle protein into amino acids
What is the preferred fuel source in stress and sepsis?
Glucose
What is insulin resistance?
Decreased cellular response to insulin, common in critical illness
What metabolic changes occur during sepsis?
Increased glucose and lactate, altered protein metabolism
How does starvation differ from stress metabolism?
Starvation leads to fat adaptation and protein sparing; stress causes protein catabolism
What is the respiratory quotient (RQ) for carbohydrate metabolism?
1
What is the RQ for fat metabolism?
0.7
What RQ suggests overfeeding?
> 1.0
What is nitrogen balance and what does a negative balance indicate?
Difference between nitrogen intake and loss; negative balance indicates catabolism
How do you calculate nitrogen balance?
Nitrogen in (g protein/6.25) – (UUN + 4)
What condition increases nitrogen losses?
Burns, trauma, sepsis, wounds
What is the goal of nutrition in the critically ill?
Prevent further loss of lean body mass, support immune function, promote healing
What is the function of iron?
Oxygen transport via hemoglobin and myoglobin
What are symptoms of iron deficiency?
Microcytic anemia, fatigue, pallor
What are causes of iron toxicity?
Hemochromatosis, iron overload from transfusions
Which populations are at risk for iron deficiency?
Infants, menstruating women, GI bleed patients
Which nutrients/meds interfere with iron absorption?
Calcium, tannins, PPIs
What is the function of zinc?
Wound healing, immune function, taste perception
What are symptoms of zinc deficiency?
Poor wound healing, alopecia, dermatitis, taste changes
Who is at risk for zinc deficiency?
Burn patients, diarrhea, TPN without zinc
What inhibits zinc absorption?
High phytate intake, high calcium/iron
What is the function of copper?
Iron metabolism, antioxidant activity
Symptoms of copper deficiency?
Microcytic anemia, neutropenia, myelopathy
Who is at risk for copper deficiency?
Gastric bypass, high zinc intake, long-term PN
Function of selenium?
Antioxidant (glutathione peroxidase), thyroid function
Symptoms of selenium deficiency?
Cardiomyopathy, muscle weakness, immune dysfunction
Who is at risk for selenium deficiency?
TPN without selenium, GI surgery
Function of manganese?
Cofactor for enzymes, bone formation
Toxicity risk for manganese?
Cholestatic liver disease—can cause neurotoxicity
Function of chromium?
Enhances insulin action
Symptoms of chromium deficiency?
Glucose intolerance, neuropathy
Who is at risk for chromium deficiency?
Long-term PN without chromium
Function of iodine?
Thyroid hormone synthesis
Symptoms of iodine deficiency?
Goiter, hypothyroidism
Toxicity of iodine?
Thyroid dysfunction
Function of fluoride?
Dental and bone health
Toxicity of fluoride?
Dental fluorosis, GI upset
Function of molybdenum?
Cofactor in amino acid metabolism
Deficiency symptoms?
Rare—tachycardia, headache, neurologic issues
What are the six ASPEN malnutrition assessment characteristics?
Energy intake, weight loss, body fat loss, muscle loss, fluid accumulation, functional status
How many criteria are needed to diagnose malnutrition per ASPEN?
At least 2 of the 6
What defines severe malnutrition (chronic)?
> 5% weight loss in 1 month or >10% in 6 months with minimal intake for >1 month
What is functional status typically assessed with?
Handgrip strength
What does SGA stand for?
Subjective Global Assessment
What are the components of SGA?
Weight change, dietary intake, GI symptoms, functional capacity, physical exam (fat/muscle loss, edema)
What are the SGA classifications?
A: well nourished, B: moderately malnourished, C: severely malnourished
What is the NUTRIC score used for?
Assessing nutrition risk in critically ill patients
What factors are included in NUTRIC?
Age, APACHE II, SOFA score, number of comorbidities, days from hospital to ICU
What does a high NUTRIC score indicate?
Greater risk of adverse outcomes, more likely to benefit from nutrition intervention
What is MUST?
Malnutrition Universal Screening Tool—used in community and outpatient settings
What is the MST?
Malnutrition Screening Tool—quick, uses weight loss and appetite
What is the MNA?
Mini Nutritional Assessment—used for elderly patients
What does %IBW =?
(Current weight / Ideal body weight) × 100
What does %UBW =?
(Current weight / Usual body weight) × 100
What does weight loss % =?
((Usual weight – current weight) / usual weight) × 100
What is considered significant weight loss?
> 5% in 1 month or >10% in 6 months
What is BMI =?
Weight (kg) / height (m)^2
What BMI is considered underweight?
<18.5 kg/m²
What BMI range is normal?
18.5–24.9 kg/m²
What are indications for parenteral nutrition (PN)?
Non-functioning GI tract, failed EN trial, bowel obstruction, severe malabsorption
When should PN be initiated in critically ill adults?
If EN is not feasible after 7 days (or earlier in malnourished patients)
What is the difference between central and peripheral PN?
Central PN allows higher osmolarity solutions; peripheral PN is limited to <900 mOsm/L
What are typical macronutrient components of PN?
Dextrose, amino acids, IV lipids
What is the max recommended glucose infusion rate (GIR)?
<4–5 mg/kg/min in adults
What is a typical lipid dosing range for PN?
0.5–1.5 g/kg/day
What is the caloric value of 20% lipid emulsion?
2 kcal/mL (10 kcal/g)
What is a concern with excessive lipid administration?
Hypertriglyceridemia, impaired immune function
What are signs of essential fatty acid deficiency?
Dry, scaly skin; alopecia; impaired wound healing
How often should lipids be given to prevent EFAD?
At least 100 g/week (2–3 times/week)
What is SMOF lipid?
Soybean oil, MCT, olive oil, fish oil mix—less pro-inflammatory
What is cyclic PN?
PN administered over <24 hours (typically 12–18 hrs/day)
What are benefits of cyclic PN?
Improved liver function, mimics normal metabolism, mobility
What are risks of starting PN too quickly?
Refeeding syndrome, hyperglycemia, electrolyte shifts
What labs should be monitored closely during PN?
Glucose, electrolytes, triglycerides, liver function tests
What are signs of PN-associated liver disease?
Elevated LFTs, cholestasis, steatosis, fibrosis
What strategies help prevent PN-associated liver disease?
Cycle PN, avoid overfeeding, use trophic EN, lipid minimization
What is the role of acetate in PN?
Converted to bicarbonate—used to manage metabolic acidosis
What is the role of chloride in PN?
Used to manage metabolic alkalosis
What are common PN complications?
Infection (catheter-related), liver dysfunction, metabolic disturbances
What is the recommended protein intake in PN for critically ill adults?
1.2–2.0 g/kg/day
What is the max osmolarity for peripheral PN?
<900 mOsm/L
How is PN osmolarity calculated?
Based on dextrose, amino acids, electrolytes—lipids don’t contribute
What organization develops nutrition support guidelines?
ASPEN (American Society for Parenteral and Enteral Nutrition)
What are ASPEN’s recommendations for initiating EN in the ICU?
Within 24–48 hours of admission if hemodynamically stable
What is the ASPEN recommendation for protein in critically ill adults?
1.2–2.0 g/kg/day
What is ASPEN’s stance on glutamine in critical illness?
Not recommended for routine use in critically ill patients
What is the FDA limit for aluminum in PN solutions?
<25 mcg/L
What must manufacturers label on PN additives per FDA?
Maximum aluminum content at expiry
What labeling standards apply to EN products?
Must list nutrient content per serving and per mL
What is a DRG?
Diagnosis-Related Group—used for hospital reimbursement
What is the role of ICD-10 codes?
Diagnosis classification used for billing and documentation
What does CPT stand for?
Current Procedural Terminology—used for procedure coding
What documentation supports nutrition reimbursement?
Nutrition diagnosis, care plan, progress notes, justification for EN/PN
What is a root cause analysis (RCA)?
Structured method for identifying underlying causes of an event
What is a PDSA cycle?
Plan-Do-Study-Act—used in QI to test and implement changes
What do JCAHO and CMS require for nutrition?
Nutrition screening within 24 hours of hospital admission
What is the purpose of a nutrition care process (NCP)?
Standardized approach to nutrition assessment and care
What is the USP <797> guideline?
Standards for sterile compounding of parenteral nutrition
What is the Hang Time recommendation for open EN systems?
4–8 hours
What is the Hang Time recommendation for closed EN systems?
Up to 24–48 hours
What are key nutrition concerns in neonates?
Immature GI function, high energy/protein needs, fluid/electrolyte sensitivity
What trace elements are typically excluded in neonatal PN?
Manganese, chromium (risk of toxicity)
What is the typical GIR range for neonates?
4–12 mg/kg/min
How is fluid calculated for neonates?
Based on weight and age in mL/kg/day
What are key nutrition goals in AKI?
Avoid overfeeding, manage electrolytes, adequate protein (1.5–2.0 g/kg if on CRRT)
What electrolytes need close monitoring in CKD/AKI?
Potassium, phosphorus, magnesium
What type of formula may be needed in renal disease?
Low electrolyte, fluid-restricted, higher calorie density
What are nutrition concerns in liver disease?
Malnutrition, fat malabsorption, ascites, electrolyte imbalances
What is the preferred type of protein in hepatic encephalopathy?
Vegetable or BCAA-rich protein
What formula adjustments may be needed in liver failure?
Energy-dense, low sodium, moderate protein
What lab indicates impaired ammonia metabolism?
Elevated serum ammonia
What is cancer cachexia?
Metabolic syndrome with weight loss, muscle wasting, inflammation
What are nutrition goals in oncology?
Maintain weight, support immune function, prevent muscle loss
When is EN preferred in oncology?
When the GI tract is functional and oral intake is inadequate
What is the nutrition focus in Crohn’s disease?
Manage flares with low-residue diet, maintain nutrient adequacy
What deficiencies are common in IBD?
Iron, B12, vitamin D, calcium
What EN formula is often used in pancreatitis?
Elemental or semi-elemental, low-fat, jejunal feeding
What are nutrition considerations in obesity during critical illness?
Use adjusted body weight for energy/protein needs
What protein range is used in critically ill obese patients?
2.0–2.5 g/kg IBW/day
What are increased needs in burn patients?
High protein (up to 2.5–3 g/kg), high calorie, fluid/electrolyte repletion
What vitamins and minerals are important in burn recovery?
Vitamin C, zinc, selenium, vitamin A
How many kcal/gram does dextrose provide in PN?
3.4 kcal/g
How many kcal/gram does protein provide?
4 kcal/g
How many kcal/gram does fat provide in EN?
9 kcal/g
How many kcal/mL does 20% IV lipid provide?
2 kcal/mL
How many kcal/mL does propofol provide?
1.1 kcal/mL
How many grams of nitrogen are in 1 gram of protein?
1 gram of nitrogen = 6.25 grams of protein
How is nitrogen balance calculated?
Nitrogen in (g protein/6.25) – (UUN + 4)
What is the goal NPC:N ratio for moderate stress?
100–150:1
What is the general adult fluid requirement?
30–35 mL/kg/day
What is the Holliday-Segar method for pediatric fluids?
100 mL/kg for first 10 kg + 50 mL/kg for next 10 kg + 20 mL/kg for each kg >20
How is glucose infusion rate (GIR) calculated?
(mg dextrose/day ÷ weight in kg ÷ 1440)
What is the max GIR for adults?
<4–5 mg/kg/min
What is the max GIR for neonates?
≤12 mg/kg/min
How is PN osmolarity calculated?
Dextrose × 5 + AA × 10 + electrolytes
What is the max osmolarity for peripheral PN?
<900 mOsm/L
What is the formula for BMI?
Weight (kg) / height (m)^2
What is the formula for IBW (female)?
45.5 kg + 2.3 kg per inch over 5 feet
What is the formula for IBW (male)?
50 kg + 2.3 kg per inch over 5 feet
How is adjusted body weight (AdjBW) calculated?
IBW + 0.25 × (ABW - IBW)
What are common energy equations?
Mifflin-St. Jeor, Harris-Benedict, Ireton-Jones, Penn State
What is the kcal/protein range for critically ill patients?
25–30 kcal/kg and 1.2–2.0 g/kg protein
When should adjusted body weight be used?
For obese patients (>120% IBW) to estimate energy/protein needs
What is refeeding syndrome?
Electrolyte shifts (↓phosphorus, potassium, magnesium) after initiating nutrition in malnourished patients
Who is at risk for refeeding syndrome?
Severely malnourished, NPO >7 days, chronic alcoholism, significant weight loss
How is refeeding syndrome prevented?
Start low and advance slowly, supplement electrolytes, monitor labs closely
What are consequences of overfeeding?
Hyperglycemia, increased CO2 production, hepatic steatosis, fluid overload
What RQ indicates overfeeding?
> 1.0
What are consequences of underfeeding?
Impaired wound healing, muscle wasting, immune dysfunction
What causes hyperglycemia in nutrition support?
Excess dextrose, stress response, insulin resistance
How is hyperglycemia managed?
Adjust dextrose load, use insulin, monitor glucose
When can hypoglycemia occur in nutrition support?
Abrupt discontinuation of PN, insulin overdose
What is PN-associated liver disease (PNALD)?
Liver dysfunction due to long-term PN use
What are signs of PNALD?
Elevated LFTs, cholestasis, steatosis
How is PNALD prevented/managed?
Avoid overfeeding, cycle PN, use enteral feeding if possible
What are signs of EN intolerance?
High gastric residuals, abdominal distention, vomiting, diarrhea
How is diarrhea from EN managed?
Adjust formula, reduce rate, add fiber or antidiarrheals
How is constipation from EN managed?
Increase fluid/fiber, stool softeners
Who is at high risk for aspiration?
Sedated, neurologically impaired, post-stroke, gastric feedings
How is aspiration risk reduced?
Elevate HOB ≥30°, post-pyloric feeding, continuous infusion
What are common enteral tube complications?
Occlusion, dislodgment, infection at site
How are occluded feeding tubes cleared?
Warm water flushes, enzymatic declogging agents
What is a CLABSI?
Central line-associated bloodstream infection
How are line infections prevented?
Aseptic technique, catheter care, ethanol locks if indicated
What causes metabolic bone disease in PN patients?
Aluminum exposure, vitamin D deficiency, low calcium/phosphorus
What are symptoms of EFAD?
Dry, scaly skin, alopecia, impaired wound healing
How is EFAD prevented?
Provide at least 100 g IV lipid per week
What defines a central venous catheter (CVC)?
Tip terminates in the superior vena cava (SVC) or right atrium
What are examples of central venous access devices?
PICC, tunneled catheter (e.g., Hickman), implanted port, non-tunneled CVC
What are advantages of central access?
Can deliver hyperosmolar solutions, long-term use
What are common insertion sites for central lines?
Subclavian, jugular, femoral
What are risks of central lines?
Infection, thrombosis, pneumothorax, catheter occlusion
What defines peripheral venous access?
Tip terminates outside of central vasculature
What is the max osmolarity for peripheral parenteral nutrition (PPN)?
<900 mOsm/L
What are disadvantages of PPN?
Short-term use, risk of phlebitis, limited calorie delivery
What is a single-lumen catheter?
One channel for infusion
What is a double-lumen catheter?
Two channels—can infuse different solutions simultaneously
What is a triple-lumen catheter?
Three channels—used in critical care or multiple infusions
Why are multiple lumens helpful?
Separate administration of incompatible medications/nutrition
What is a nasogastric (NG) tube?
Inserted through the nose into the stomach—short-term use
What is a nasojejunal (NJ) tube?
Inserted through the nose into the jejunum—post-pyloric feeding
What is a gastrostomy (G-tube)?
Tube placed directly into the stomach—long-term EN
What is a jejunostomy (J-tube)?
Tube placed directly into the jejunum—used if stomach not functional
What is a PEG tube?
Percutaneous endoscopic gastrostomy—G-tube placed via endoscopy
What is a PEJ tube?
Percutaneous endoscopic jejunostomy—J-tube placed via endoscopy
What is the difference between balloon vs. non-balloon G-tube?
Balloon: easier at-home replacement; Non-balloon: more secure
What is a low-profile G-tube?
Flush with skin, used for active patients
How is enteral tube patency maintained?
Flush with water before/after feeding or medication
What is a common cause of tube occlusion?
Medication residue, inadequate flushing
How can clogged tubes be cleared?
Warm water flushes, enzyme-based unclogging kits (no soda or juice)
What is a drug-nutrient interaction?
A reaction between a drug and a nutrient that affects absorption, metabolism, or excretion of either
What is the interaction between phenytoin and EN?
EN decreases phenytoin absorption
How to manage phenytoin interaction with EN?
Hold tube feeds 1–2 hours before and after dosing
How does warfarin interact with nutrition?
Vitamin K intake can reduce warfarin effectiveness
How to manage warfarin interaction?
Maintain consistent vitamin K intake
What nutrient deficiencies can PPIs cause?
Vitamin B12, magnesium, calcium
What are nutrition concerns with corticosteroids?
Hyperglycemia, increased protein breakdown, bone loss
What are nutrient losses associated with loop diuretics?
Potassium, magnesium, calcium, thiamine
What is a key nutritional concern with thiazide diuretics?
Hypercalcemia and potassium loss
What nutrient interactions occur with cholestyramine?
Decreases absorption of fat-soluble vitamins (A, D, E, K)
What is a common nutrient concern with prolonged antibiotic use?
Vitamin K deficiency and altered gut microbiota
What decreases iron absorption?
Calcium, PPIs, antacids, tannins (tea/coffee)
What enhances iron absorption?
Vitamin C and acidic environment
What nutrient should be supplemented with methotrexate?
Folic acid
What nutrient competes with levodopa for absorption?
Protein—high protein meals can reduce drug effectiveness
What drug is lipid-based and contributes calories?
Propofol (1.1 kcal/mL)
What vitamins are light-sensitive and degrade in TPN?
Vitamins A, C, and B1 (thiamine)
What trace element should be monitored in patients on long-term PPI or H2RA therapy?
Magnesium
What are the indications for enteral nutrition (EN)?
Functioning GI tract, unable to meet needs orally for >2–3 days
When should EN be initiated in critically ill patients?
Within 24–48 hours of ICU admission
What are contraindications to EN?
Non-functioning GI tract, bowel obstruction, hemodynamic instability
What are common routes for EN?
Nasogastric, nasojejunal, gastrostomy, jejunostomy
What is the difference between gastric and post-pyloric feeding?
Gastric: easier placement, higher aspiration risk; Post-pyloric: lower aspiration risk, for high reflux/vomiting
What are polymeric formulas?
Standard EN formulas with intact protein, fat, and carbohydrates
What are elemental/semi-elemental formulas?
Formulas with hydrolyzed proteins, for malabsorption or GI dysfunction
What is a modular formula?
Customizable formula components (e.g., protein powder, glucose polymers)
What is the recommended protein intake in EN for critically ill adults?
1.2–2.0 g/kg/day
What is the typical goal for EN advancement?
Reach goal rate within 48–72 hours if tolerated
What are signs of EN intolerance?
High gastric residuals, abdominal distension, vomiting, diarrhea
What is refeeding syndrome?
Fluid and electrolyte shifts (↓phos, K, Mg) when feeding is initiated after starvation
How can refeeding syndrome be prevented?
Start low and go slow, supplement electrolytes, monitor labs closely
How should medications be given via feeding tube?
Use liquid forms or crushable tablets, flush before/after administration
Which drugs interact with tube feeds?
Phenytoin, warfarin, fluoroquinolones—require holding feeds before/after
What is the difference between open vs. closed EN systems?
Open: decanted, increased contamination risk; Closed: prefilled, safer, longer hang time
What is the typical hang time for open EN systems?
4–8 hours
What is the typical hang time for closed EN systems?
Up to 24–48 hours
How much free water is in most standard EN formulas?
About 80%
What is the typical calorie density of standard EN formulas?
1.0–1.2 kcal/mL
What calorie density is considered energy-dense?
≥1.5 kcal/mL, used for fluid restriction
What is the typical fluid requirement for adults?
30–35 mL/kg/day
What is the Holliday-Segar method for pediatric fluid needs?
100 mL/kg for first 10 kg + 50 mL/kg for next 10 kg + 20 mL/kg for weight >20 kg
What are signs of fluid overload?
Edema, hypertension, pulmonary congestion
What are signs of dehydration?
Hypotension, tachycardia, decreased urine output, elevated BUN/Cr
Normal serum sodium range?
135–145 mEq/L
What does hyponatremia indicate?
Fluid overload, SIADH, renal failure
What does hypernatremia indicate?
Dehydration, diabetes insipidus
Normal serum potassium range?
3.5–5.0 mEq/L
Causes of hypokalemia?
Diuretics, GI losses, refeeding syndrome
Causes of hyperkalemia?
Renal failure, acidosis, tissue breakdown
Normal serum calcium range?
8.5–10.5 mg/dL
What should you check in hypoalbuminemia?
Corrected calcium
Corrected calcium formula?
Measured Ca + 0.8 × (4 - serum albumin)
Causes of hypocalcemia?
Vitamin D deficiency, pancreatitis, low magnesium
Causes of hypercalcemia?
Hyperparathyroidism, malignancy
Normal serum phosphorus range?
2.5–4.5 mg/dL
Causes of hypophosphatemia?
Refeeding syndrome, TPN without phosphorus, DKA
Causes of hyperphosphatemia?
Renal failure, tumor lysis syndrome
Normal serum magnesium range?
1.5–2.5 mg/dL
Causes of hypomagnesemia?
Diarrhea, alcoholism, diuretics
Causes of hypermagnesemia?
Renal failure, excessive supplementation
What is metabolic acidosis?
Low pH, low HCO3; causes: diarrhea, renal failure, ketoacidosis
What is metabolic alkalosis?
High pH, high HCO3; causes: vomiting, diuretics
What is respiratory acidosis?
Low pH, high CO2; causes: hypoventilation, COPD
What is respiratory alkalosis?
High pH, low CO2; causes: hyperventilation, anxiety
Where does most nutrient absorption occur?
Small intestine (primarily jejunum)
What is the function of the ileum?
Absorbs bile salts, vitamin B12, and some water/electrolytes
What is the role of the colon in digestion?
Absorbs water, electrolytes, short-chain fatty acids
What is the function of the pancreas in digestion?
Secretes enzymes for digestion of protein, fat, and carbohydrates
Where is intrinsic factor produced and what is its role?
Stomach; binds to vitamin B12 for absorption in the ileum
What is short bowel syndrome (SBS)?
Malabsorption from significant loss of small bowel surface area
What are nutrition concerns in SBS?
Fluid/electrolyte imbalance, fat malabsorption, nutrient deficiencies
Which part of the bowel can adapt best after resection?
Jejunum
Which part is most difficult to compensate for if resected?
Ileum
What is the role of the colon in patients with SBS?
Colon helps absorb fluids, SCFAs—important if ileum resected
What is small intestinal bacterial overgrowth (SIBO)?
Excessive bacteria in small bowel causing bloating, diarrhea, malabsorption
Risk factors for SIBO?
Stasis, strictures, blind loops, motility disorders
What is the role of bile salts?
Emulsify fats for digestion and absorption
What happens when bile salts are malabsorbed?
Fat malabsorption, steatorrhea, loss of fat-soluble vitamins
What is the concern with pancreatic insufficiency?
Inadequate digestion of fat/protein, leading to steatorrhea and malnutrition
How is pancreatic insufficiency managed?
Pancreatic enzyme replacement therapy (PERT) with meals/snacks
What is a chyle leak?
Loss of lymphatic fluid rich in fat/protein/electrolytes
How is a chyle leak managed nutritionally?
Low-fat or MCT-based diet; may require EN or PN
What is bile acid diarrhea?
Occurs after ileal resection; bile salts enter colon causing fluid secretion
Treatment for bile acid diarrhea?
Bile acid sequestrants (e.g., cholestyramine)
What is an anastomosis?
Surgical connection between two parts of the bowel
What is a fistula?
Abnormal connection between bowel and another surface or organ
What is high-output fistula defined as?
> 500 mL/day output
Normal fasting glucose range?
70–99 mg/dL
What is hyperglycemia defined as?
> 180 mg/dL
What is hypoglycemia defined as?
<70 mg/dL
Normal sodium range?
135–145 mEq/L
Normal potassium range?
3.5–5.0 mEq/L
Normal chloride range?
98–106 mEq/L
Normal CO2 (bicarb) range?
22–28 mEq/L
Normal calcium range?
8.5–10.5 mg/dL
Normal magnesium range?
1.5–2.5 mg/dL
Normal phosphorus range?
2.5–4.5 mg/dL
What does elevated AST/ALT suggest?
Hepatocellular injury
What does elevated ALP and bilirubin suggest?
Cholestasis or bile duct obstruction
What does elevated direct bilirubin indicate?
Obstructive or hepatocellular jaundice
What is prealbumin used to assess?
Short-term changes in nutrition status
Why is prealbumin not reliable in critically ill patients?
It is a negative acute-phase reactant
What is CRP used for?
Marker of inflammation
What does a high CRP indicate?
Acute inflammation, infection, or trauma
What does elevated BUN/creatinine indicate?
Dehydration or renal dysfunction
What does a high BUN:Cr ratio suggest?
Pre-renal azotemia (often due to dehydration)
What is a normal BUN:Cr ratio?
10:1 to 20:1
What lab reflects iron storage?
Ferritin
What lab reflects recent iron status?
Serum iron, transferrin saturation
What labs suggest iron deficiency anemia?
Low Hgb, low Hct, low ferritin, high TIBC
What lab is used to assess vitamin D status?
25(OH)D
What lab decreases in zinc deficiency?
Alkaline phosphatase
What labs are monitored for refeeding syndrome?
Phosphorus, potassium, magnesium
What does elevated ammonia indicate?
Liver failure, especially in hepatic encephalopathy
What does an RQ >1.0 suggest?
Overfeeding, lipogenesis
How many kcal/gram does dextrose provide in PN?
3.4 kcal/gram
How many kcal/gram does protein provide in EN/PN?
4 kcal/gram
How many kcal/gram does lipid provide in PN?
10 kcal/gram (from 20% lipid emulsion)
How many kcal/gram does lipid provide in EN?
9 kcal/gram
What is the typical non-protein calorie to nitrogen ratio (NPC:N) in PN?
100–150:1
What is the purpose of the NPC:N ratio?
To ensure adequate calories to spare protein for tissue repair and growth
How many grams of nitrogen are in 1 gram of protein?
1 gram of nitrogen = 6.25 grams of protein
What macronutrient has the highest respiratory quotient (RQ)?
Carbohydrates (RQ ~1.0)
What macronutrient has the lowest respiratory quotient (RQ)?
Fat (RQ ~0.7)
What is the typical protein range in PN for a critically ill adult?
1.2–2.0 g/kg/day
What is the minimum amount of carbohydrate needed to prevent ketosis?
100–150 g/day
What is a concern with excessive carbohydrate intake in PN?
Hyperglycemia, increased CO2 production, hepatic steatosis
What is a concern with excessive fat intake in PN?
Hypertriglyceridemia, impaired immune function
What are the components of TPN macronutrients?
Dextrose, amino acids, lipids
How many kcal/gram does dextrose provide in PN?
3.4 kcal/g
How many kcal/gram does protein provide?
4 kcal/g
How many kcal/gram does fat provide in EN?
9 kcal/g
How many kcal/mL does 20% IV lipid provide?
2 kcal/mL
How many kcal/mL does propofol provide?
1.1 kcal/mL
How many grams of nitrogen are in 1 gram of protein?
1 gram of nitrogen = 6.25 grams of protein
How is nitrogen balance calculated?
Nitrogen in (g protein/6.25) – (UUN + 4)
What is the goal NPC:N ratio for moderate stress?
100–150:1
What is the general adult fluid requirement?
30–35 mL/kg/day
What is the Holliday-Segar method for pediatric fluids?
100 mL/kg for first 10 kg + 50 mL/kg for next 10 kg + 20 mL/kg for each kg >20
How is glucose infusion rate (GIR) calculated?
(mg dextrose/day ÷ weight in kg ÷ 1440)
What is the max GIR for adults?
<4–5 mg/kg/min
What is the max GIR for neonates?
≤12 mg/kg/min
How is PN osmolarity calculated?
Dextrose × 5 + AA × 10 + electrolytes
What is the max osmolarity for peripheral PN?
<900 mOsm/L
What is the formula for BMI?
Weight (kg) / height (m)^2
What is the formula for IBW (female)?
45.5 kg + 2.3 kg per inch over 5 feet
What is the formula for IBW (male)?
50 kg + 2.3 kg per inch over 5 feet
How is adjusted body weight (AdjBW) calculated?
IBW + 0.25 × (ABW - IBW)
What are common energy equations?
Mifflin-St. Jeor, Harris-Benedict, Ireton-Jones, Penn State
What is the kcal/protein range for critically ill patients?
25–30 kcal/kg and 1.2–2.0 g/kg protein
When should adjusted body weight be used?
For obese patients (>120% IBW) to estimate energy/protein needs
What is refeeding syndrome?
Electrolyte shifts (↓phosphorus, potassium, magnesium) after initiating nutrition in malnourished patients
Who is at risk for refeeding syndrome?
Severely malnourished, NPO >7 days, chronic alcoholism, significant weight loss
How is refeeding syndrome prevented?
Start low and advance slowly, supplement electrolytes, monitor labs closely
What are consequences of overfeeding?
Hyperglycemia, increased CO2 production, hepatic steatosis, fluid overload
What RQ indicates overfeeding?
> 1.0
What are consequences of underfeeding?
Impaired wound healing, muscle wasting, immune dysfunction
What causes hyperglycemia in nutrition support?
Excess dextrose, stress response, insulin resistance
How is hyperglycemia managed?
Adjust dextrose load, use insulin, monitor glucose
When can hypoglycemia occur in nutrition support?
Abrupt discontinuation of PN, insulin overdose
What is PN-associated liver disease (PNALD)?
Liver dysfunction due to long-term PN use
What are signs of PNALD?
Elevated LFTs, cholestasis, steatosis
How is PNALD prevented/managed?
Avoid overfeeding, cycle PN, use enteral feeding if possible
What are signs of EN intolerance?
High gastric residuals, abdominal distention, vomiting, diarrhea
How is diarrhea from EN managed?
Adjust formula, reduce rate, add fiber or antidiarrheals
How is constipation from EN managed?
Increase fluid/fiber, stool softeners
Who is at high risk for aspiration?
Sedated, neurologically impaired, post-stroke, gastric feedings
How is aspiration risk reduced?
Elevate HOB ≥30°, post-pyloric feeding, continuous infusion
What are common enteral tube complications?
Occlusion, dislodgment, infection at site
How are occluded feeding tubes cleared?
Warm water flushes, enzymatic declogging agents
What is a CLABSI?
Central line-associated bloodstream infection
How are line infections prevented?
Aseptic technique, catheter care, ethanol locks if indicated
What causes metabolic bone disease in PN patients?
Aluminum exposure, vitamin D deficiency, low calcium/phosphorus
What are symptoms of EFAD?
Dry, scaly skin, alopecia, impaired wound healing
How is EFAD prevented?
Provide at least 100 g IV lipid per week
What defines a central venous catheter (CVC)?
Tip terminates in the superior vena cava (SVC) or right atrium
What are examples of central venous access devices?
PICC, tunneled catheter (e.g., Hickman), implanted port, non-tunneled CVC
What are advantages of central access?
Can deliver hyperosmolar solutions, long-term use
What are common insertion sites for central lines?
Subclavian, jugular, femoral
What are risks of central lines?
Infection, thrombosis, pneumothorax, catheter occlusion
