Module 5: Nutrition Dr. Covert Flashcards
EXAM VI
What are the different routes of enteral nutrition?
-uses GI tract
-PO
-per feeding tube (still enters the GI)
if the GI tract has not been used after a period of time, the peristalsis is less active
What are the different routes of parenteral nutrition?
-IV
-does NOT use GI
-parietal cells not active, no peristalsis, pancreas will not secret enzymes, no gut stimulation
Pros of Enteral Nutrition
-stimulation of the gut (keep GI functioning, peristalsis)
-lower risk of infection
-less hepatic/biliary complication (bc still used and stimulated)
-decrease in hyperglycemia (fewer glycemic swings when eating carb-rich food)
Cons of Enteral Nutrition
-Aspiration (pneumonia)
-may induce diarrhea (high osmotic load in the formula)
-malabsorption (bc it moves so quickly through the body)
-hyperglycemia
-tube irritation (uncomfortable)
-tube occlusion
Which patient population is eligible for enteral nutrition?
-functional GI tract!
-unable to take PO
-safe enteral access possible (patients ripping their tubes off)
-critical ill patients
Patients excluded from enteral nutrition
-intestinal obstruction (eg esophageal cancer)
-bowel ischemia, Crohn’s disease
-active peritonitis
-severe pancreatitis
-severe hemodynamic instability (less perfusion to the gut due to low BP)
-toxic megacolon in C. diff (removing a big part of the colon - can’t absorb food or meds)
What are the surgically placed tube insertions?
-PEG (short-term)
-PEJ (short-term)
-J-tube (long-term)
Which tubes may be used if a patient is unconscious and needs quick access?
NG tube
NJ tube
ND tube
Orogasstric (OG)
via stomach = short and long-term
-works quickly, short-term
-can give food and crushed meds
What are the Formulations for food delivery?
-Continuous: 16-24h/day -> small volume over time, les N/V, but it is not physiologic to continuously be fed
-Cyclic (larger volume over a shorter period of time)
-Intermittent (large volume at once, often outpatient)
-Bolus (large volume at once, often outpatient)
+ sorter duration for being on the feeding tube
What are the physiological disadvantages of continuous administered nutrition?
-it is not physiologic
-blood sugar dysregulation
-constant pancreatic secretion of enzymes and insulin
ADR of enteral nutrition
-GI intolerance
-tube occlusion
-aspiration
-fluid/electrolyte changes
-hyperglycemia
-dehydration (need free water)
Monitoring - Enteral nutrition
-weight
-BMP (K, glucose)
-Mg/Ph
-volume status (TNP with high calories in low volume, may need supplemental free water, in ESRD of HF patient is may be fine bc they won’t tolerate fluids anyway)
Medication Considerations - Site of action
EXAM
Drug use with tubes
-site of action: J-tube works in the jejunum, parietal cells are only present in the stomach -> so take off PPIs; enteric-coated drugs meant to bypass the stomach -> when used in NJ tube they would be released further down the stomach
-take off carafate it works in the stomach
-site of absorption: often rely on an acidic environment, which is bypassed with J-tubes and NEJ tubes
Medication Considerations - Liquid formulas
EXAM
-liquid meds with high osmotic load, fe Augmentin has a lot of sugar
-irritating to the gut -> diarrhea
-stomach upset
when switching from PO to liquid the volume might be so high that is not tolerable for the patient
Why should meds never be mixed with enteral formula?
Medication Considerations
EXAM
-meds will bind, and interact with the food, and may deactivate
Why must the tube be flushed after giving meds?
-long tube -> long way to travel
-flush after giving the meds to make sure everything goes through
Can drugs be crushed?
-for most immediate-release meds it is fine
-not for extended-release meds -> it may release the entire dose at once - overdose
-fe MS Contin, 5-ASA (enteric-coated)
What needs to be considered when giving Phenytoin to patients on enteral nutrition?
-Hold feeds 1-2h before and after giving Phenytoin to prevent decreased absorption (given TID - not easy to manage)
-low absorption when given with enteral nutrition -> may not be able to prevent the seizure
What needs to be considered when giving Warfarin and FQ to patients on enteral nutrition?
Warfarin:
-adjust Warfarin to INR
-some EN formulas have more or less Vitamin K content
FQ:
-hold feeds 1-2h before and after giving FQ
-lower bioavailability due to chelation with cations in the EN formula
What are the Macronutrients in Parental Nutrition?
EXAM
-Protein: 4 kcal/g
-Fat: 9 kcal/g
-Carbohydrates: 3.4 kcal/g
Pros of Parental Nutrition
-don’t rely on the GI function
Cons of Parental Nutrition
-infection
-hepatic or biliary complications -> constantly stimulating bile acid secretion to breakdown fats in the formula -> gallstones, gallbladder slugging
-catheter thrombosis
-hyperglycemia
-electrolyte abnormalities
-osteoporosis (long-term) bc less Vitamin K absorption
Who is eligible for Parenteral Nutrition?
.-patients with Malabsorption who can’t be fed by enteral nutrition for 7-10 days
-Bowel resection
-Bowel obstruction
-GI fistula
-severe cancer in the gut
-patients with functional GI should get enteral nutrition!
Partial Parental Nutrition (PPN)
-via small vein (due to osmolality)
-temporary
-does not provide full nutrition
-PPN not often used anymore
Total Parental Nutrition (TPN)
-via large vein, a large vein is needed bc of the high osmotic load
-may be used long-term
-can provide full nutrition
Which factors are used to assess a patient’s eligibility for TPN?
-Body weight
-BMI
-Nutrition history (how long have they been NPO, nothing by mouth)
-physical exam
What is refeeding syndrome
-feeding patients too quickly after malnutrition for a long period of time
-the body’s metabolism has shifted to breakdown as an energy source -> when refeeding to quickly it shifts back to carb metabolism to use carbs as an energy source
-it causes a spike in insulin -> reduces blood sugar -> hypoglycemia
-for the body to use the energy from the carbs -> the body needs phosphorus to generate ATP -> high demand and depletion of phosphorus (lower than 1) -> leads to cardiac arrhythmia -> may cause death
How to manage refeeding syndrome
Monitor: electrolytes, glucose, feed slowly
-give 50% of daily intake
Risk factor of Refeeding Syndrome
+1
-BMI < 16
-unintentional weight loss by 15% in the last 3-6 months
-little or no nutrition for 10 days
-Low K, Phos, Mag before feeding
+2
-BMI < 18.5
-unintentional weight loss by 10% in the last 3-6 months
-little or no nutrition for 5 days
-H/ EtOH/ drug use
When to use actual BW vs IBW
-BMI <30: actual BW
-BMI >30: IBW
When is a total caloric intake of 25-30 kcal/kg/day recommended?
STEP 1 Calories
-most patients
-maintenance
-elective surgery
-medical ICU
-minor infection
-minor surgery
the weight (TBW vs IBW) that is used depends on the BMI
When is a total caloric intake of 30-35 kcal/kg/day recommended?
STEP 1 Calories
-major trauma
-major surgery
-major stress
What does the number of calories tell me?
-total number of calories per day
-so protein, fats, and carbs together has to equal the number of calories
What are the Protein needs for different patient populations?
STEP 2 Protein
-Maintenance (home TPN): 1g /kg/day
-moderate stress: 1.5 - 2g /kg/day
-severe stress: 2 - 2.5g /kg/day
-renal impairment:
Non-HD: 1.2g /kg/day
HD: 1.2 - 1.5g /kg/day
CVVHD: 2 - 2.5g /kg/day
How would the daily protein needs be adjusted in patients with renal impairment?
-reduced protein needs bc the kidneys are responsible for processing proteins
How many calories are in 110g of Protein?
4 kcal/g
110 g x 4 kcal = 440 kcal
1800 total kcal -> so 1360 kcal left (non-protein calories)
Fat/Lipids
Step 3
-20-30% of the non-protein calories should come from fat (fat should not exceed 60% of non-protein calories -> hypertriglyceridemia)
OR
0.5 - 1g/kg/day
consider drugs with large fat content
Which medications are known to have a high-fat content?
-Propofol: 1.1 kcal/ml
-Clevidipine: 2 kcal/ml
What are the prepared fat products?
-SMOFlipid (preferred, less inflammatory)
-Intralipid
-comes in 10% or 20%
Calculation fat
1360 kcal left (non-protein calories)
-fat should be 20-30% of non-protein-calories
OR 0.5-1g/kcal/day -> fat = 9kcal/g
calculate 0.5 -1g from act BW -> multiply with 9 kcal
292-585 kcal/day
= 272-408 kcal should come from fat
-subtract the fats that came from drugs to determine how much should come from foods
How much kcal should come from dextrose/carbs?
Step 4: carbs
~15-20 kcal/kg/day
-should not exceed 25 kcal/kg/day -> cholestasis (liver disease), difficulty weaning from the ventilator
-check what is left for carbs and divide by BW
-check if the result is in the range
-if too high increase fats or protein
Step 5: Fluids
1st 10 kg: 100 ml/ kg = 100 * 10kg = 1000 ml
next 10 kg: 50 ml/kg = 50 * 10 kg = 500 ml
rest: 20 ml/k = 20 * (Wt - 20kg) (remaining of the BW)
-patients with HF might not get full amount of fluids bc it worsen their condition
Step 6: Multivitamins and Trace elements
-multivitamins are usually already in the TPN
-Trace elements
MTE-5: Zinc, copper, chromium, manganese, selenium
MTE-4: no selenium (renal elimination so use for ESRD patients)
FYI:
-if renal disease: no selenium
-if liver disease: no manganese or copper
-high-output fistulas (>500ml/day): consider zinc supplements
Step 7: Electrolytes
-trends of electrolytes can be managed via TPN
-> patient with HFrEF have chronically low K due to daily loop diuretic
-acute changes in electrolytes should be managed by boluses
-> fe hypokalemia secondary to fluid resuscitation due to septic shock
How to replenish electrolytes
-replenish K: 10 meq = 0.1
PO is preferred bc IV irritation but he can’t get PO with Crohn’s disease
infusion rate:
-Mag controls K (replenish Mag first?)
-Phosphate:
NaPhos: 14-45 mmol
K Phos: 14-45 mmol -> can be given when the patient is low in K
-Ca2+: calcium gluconate (preferred IV): 2-3 g
(adjustment for albumin)
