Parenteral and Enternal Nutrition - Lecture 3

Question 1

EN - if the ____ works, use it

Answer 1

gut

Question 2

EN indications

Answer 2

oral consumption inadequate
oral consumption contraindicated: esophageal obstruction, head and neck surgery, dysphagia, trauma, cerebrovascular accident, dementia

Question 3

Advantages of EN

Answer 3

provides GI stimulation: decreased chance for bacterial translocation, stimulates biliary flow through biliary tract
avoids risks associated with IVs: non-invasive tube placement at the bedside, line infections, pneumothorax
more physiologic than PN
bolus feeds are more physiologic than continuous
less stringent protocl for administration
less expensive

Question 4

Decreased bacterial translocation leads to

Answer 4

decreased infectious morbidity and mortality with EN
time-dependent passage of bacteria or endotoxins from GI tract to extra-intestinal sites
enteric organisms cause systemic infections: pneumonia, central line infections, abscesses, multi-organ dysfunction syndrome

Question 5

Contraindications to EN

Answer 5

so need to use PN
mechanical obstruction: hernia, tumors, adhesions, scar tissue
non-mechanical obstruction - ileus: no peristalsis, decreased perfusion, post-op
intractable vomiting
severe malabsorption
severe GI hemorrhage
certain types of fistulas: high output, proximal small bowel

Question 6

Routes of administration for EN

Answer 6

nasogastric/orogastric (can put meds down)
nasojejunal/orojejunal
gastrostomy: PEG
jejunostomy; PEG/PEJ

Question 7

Determining route of access

Answer 7

risk of aspiration: if low risk - may utilize gastric, if high risk - jejunal is preferred
tolerance: vomiting or gastric residuals - use jejunal
duration of therapy: long term - consider PEG or PEJ

Question 8

Confirm proper placement

Answer 8

verify before initiating feeding: post-pyloric, lung placement, pneumothorax
auscultation
abdominal x-ray: kidneys, ureters, bladder
cortrak: real-time display of position during placement, no imaging required

Question 9

Methods of administration

Answer 9

bolus, intermittent, continuous infusion, trickle or trophic

Question 10

Bolus

Answer 10

mimics meals (giving multiple boluses a day)
administer > 200 mL formula over 5-10 min, max volume 300-400 mL
used primarily for pts with gastrostomy: nursing facilities, ambulatory settings

Question 11

Bolus advantages and disadvantages

Answer 11

advantages: more convenient for pts; requires minimal equipment (syringe); less med interactions
disadvantages: cannot feed into small bowel, higher risk of aspiration (b/c feeds are in stomach) and intestinal side effects

Question 12

Intermittent

Answer 12

administer > 200 mL formula over 20-30 min (gravity drip)
4-8 feedings/day
advantage: helps tolerance
disadvantage: more equipment required (requires use of reservoir bottle or bag)

Question 13

Continuous infusion (most common in hospital)

Answer 13

administer continuously over 12-24 hrs/day
requires use of infusion pump
preferred method when feeding into jejunum

Question 14

Continuous infusion advantages and disadvantages

Answer 14

advantages: lower risk of gastric distention and aspiration; better tolerated by pt
disadvantages: problematic for med administration; requires infusion pump

Question 15

Trickle or trophic

Answer 15

run at low rate: slow continuous infusion at 10-30 mL/hr
advantages: prevent mucosal atrophy + bacterial translocation; may shorten time on ventilator and decrease mortality
disadvantage: difficult to achieve sufficient calorie delivery

Question 16

Initiation and advancement of tube feeding

Answer 16

intitiate full strength at 25 mL/h
advance 25 mL/h q 4-6hrs as tolerated up to goal rate: check residuals q4-6hrs, may hold for residuals > 500mL
dilution of formula has limited benefit (not recommended)

Question 17

Cyclic

Answer 17

administer over 8-10 hrs/day
often infused overnight
advantage: increased independence for pt

Question 18

EN - ICU initiation points

Answer 18

achieve > 50-60% goal calories within 1st week
don’t initiate if hemodynamically unstable: concern for intestinal ischemia (shunt blood flow to vital organs, gut will die if not perfusing, i.e. vasopressor)
bowel sounds or flatus not needed for initiation: EN promotes gut motility

Question 19

NPO times

Answer 19

minimize holding times: inadequate nutrient delivery; may stimulate ileus development
pts undergoing frequent surgical procedures have fewer infections when EN is not stopped for each procedure

Question 20

Formula selection

Answer 20

pt characteristics: functional capacity of GI tract, underlying disease, nutritional requirements
formulary availability

Question 21

Formula examples

Answer 21

jevity, impact 1.5, glucerna, nepro
higher the # of kcal/mL or protein = more concentrated (can give more calories with less volume)

Question 22

Immune-modulating contents (impact 1.5)

Answer 22

arginine: T lympocyte fx
glutamine: antioxidant, immune support, nitrogen retention
omega-3 FA: reduced inflammation, arrhythmia incidence, ARDS, and sepsis
antioxidants: selenium, ascorbic acid, vit E

Question 23

Target pt populations with impact 1.5

Answer 23

major elective surgery, trauma, burn, head or neck cancer, mechanically ventilated
use with caution: sever sepsis
benefits of impact 1.5: reduced time on ventilator, infectious morbidity, length of hospital stay

Question 24

EN nutrient composition - protein

Answer 24

intact protein: requires complete digestion into smaller peptides
partially digested (peptide-based): elemental (easier for body to process), may be beneficial for pts with malabsorption, diarrhea

Question 25

EN nutrient composition - fat

Answer 25

long-chain fatty acids
medium chain fatty acids: more water soluble; rapid hydrolysis, little or no pancreatic lipase for absorption

Question 26

EN nutrient composition - carbohydrates

Answer 26

glucose polymers primarily used for tube feeding formulas
simple glucose used for oral supplements (higher in osmolality)

Question 27

Adjunctive therapies

Answer 27

can give these with tube feeds
modular supplements
glutamine
probiotics
vitamins and trace elements

Question 28

Modular supplements - most common

Answer 28

pro-stat: category - protein
15g protein
72 kcal
3g CHO

Question 29

Other modular supplements

Answer 29

nutrisource, fiber, benefiber: category - fiber
juven: category - wound care, HIV/AIDs, cancer
glutasolve: category - glutamine (for burn pts)

Question 30

Glutamine

Answer 30

may reduce hospital and ICU length of stay
reduces mortality in burn pts
no systemic effect when given by enteral route - will help maintain gut integrity
0.3-0.5 g/kg/day divided into 2-3 doses
do NOT supplement if already receiving glutamine via immune modulating formula (impact 1.5)

Question 31

Probiotics

Answer 31

microorganisms conferring potential health benefits to host: inhibit pathogenic bacterial growth, block pathogen attachment, eliminate toxins, enhance host inflammatory response
clinical efficacy data are mixed/lacking
may increase complications (diarrhea)

Question 32

Vitamins and trace elements

Answer 32

used for antioxidant effects and/or repletion
vit E and vit C
trace elements: selenium, zinc, copper, chromium, manganese
beneficial in most ICU pts: emphasis on burn, trauma, mechanically ventilated
consider organ dysfunction as previously discussed

Question 33

Complications

Answer 33

gastrointestinal
metabolic
mechanical
medication-related

Question 34

Complications - gastrointestinal

Answer 34

high gastric residuals
aspiration
nausea/vomiting or decreased motility: consider prokinetic medications; metoclopramide, erythromycin may be given
abdominal distention
diarrhea
constipation

Question 35

High gastric residuals

Answer 35

lower cut offs do not protect pt from complications
residuals: <500 mL - do not hold unless intolerance signs; 200-500 mL - implement risk reduction measures to avoid aspiration; cutoffs may vary by site

Question 36

Aspiration risk reduction

Answer 36

elevate HOB 30-45 degrees: gravity can drain things out of lungs and move tube feeds
administer as continous infusion
change to post-pyloric delivery
consider prokinetic drugs or narcotic antagonists

Question 37

Decreased motility: consider prokinetic agents

Answer 37

metoclopramide
erythromycin
naloxone (if given enterally, doesn’t affect pain meds)
methynaltrexone

Question 38

Diarrhea

Answer 38

formula: change to soluble fiber-containing or small peptide formulations
suspect clostridium difficile colitis (if high fever and continous diarrhea)
consider other infectious etiologies
evaluate meds: hyperosmolar meds, liquid formulations with sorbitol, bowel regimen, broad specturm antibiotics

Question 39

Complications - metabolic

Answer 39

hype- or hypoglycemia: check meds, insulin regimen, stress, infection
overhydration; dehydration: monitor fluid status
electrolyte imbalance: hyponatremia most common

Question 40

Glyemic control in ICU

Answer 40

goal blood glucose = </- 180 mg/dL
NICE-SUGAR study found increased mortality and higher rate of hypoglycemia with tight blood glucose control

Question 41

Complications - Mechanical

Answer 41

clogging of feeding tube
tube malposition (abdominal x-ray (KUB))
rhinitis: reposition daily, use smaller bore tube, change from NG to OG
sinusitis

Question 42

Complications - medication related

Answer 42

clogged feeding tubes
drug-tube feed interactions

Question 43

General guidelines for medication delivery via enteral feeding tubes

Answer 43

liquid medications are preferred whenever possible
is using oral dosage forms, crush the tablet to a fine powder (or empty capsule contents) and mix in water
DO NOT crush sustained-release or enteric coated formulations!
administer each med separately
ensure adequate flushing with water between each med
dilute hypertonic meds or those irritating to the gastric mucosa in at least 30 mL of water before administering

Question 44

Liquid medications preferred

Answer 44

avoid viscous formulations due to risk of clogging tube: syrups, mineral oil, granules
can sometimes crush tabs or open capsules - dilute in 15-30 mL of sterile water

Question 45

Do not crush list

Answer 45

delayed/extended release
enteric coated
buccal or sublingual
carcinogenic, teratogenic, cytotoxic
+/- capsules (if you can open, ok to give)

Question 46

Clogged feeding tubes

Answer 46

poorly crushed meds
inadequate flushing: flush with at least 15-30 mL of sterile water before and after med adminsitration; flush with 5-10 mL between each med
flushing also ensures adequate med administration

Question 47

Unclogging the tube

Answer 47

1 sodium bicarb tab + 1 pancreatic enzyme capsul into 10 mL of warm sterile water - place slurry into feeding tube
clamp tube for 15-30 min
flush when complete

Question 48

Drug/tube feed interactions - antibiotics

Answer 48

fluroquinolones, itraconazole solution, tetracyclines, penicillin V

Question 49

Drug/tube feed interactions - anti-retrovirals

Answer 49

didanosine
dolutegravir
indinavir

Question 50

Drug/tube feed interactions - other

Answer 50

levothyroxine, phenytoin, theophylline, warfarin

Question 51

Drug/tube feed interactions - what to do

Answer 51

hold tube feed –> wait 1 hr –> give med –> wait 2 hrs –> resume tube feed

Question 52

Monitoring

Answer 52

gastrointestinal
metabolic
mechanical

Question 53

Monitoring - gastrointestinal

Answer 53

gastric residuals
emesis
check q4-6hrs
stools daily: frequency of stools, volume of stools
bloating/distention
bronchial/tracheal aspirate

Question 54

Monitoring - metabolic

Answer 54

intake/output; bowel movements
weight –> 2-3 times/week
serum electrolytes, glucose, BUN/SCr [CMP]: daily until stable –> twice weekly –> weekly
Mg, phos, ca, triglycerides, LFTs: weekly
albumin, prealbumin/CRP, nitrogen balance: weekly

Question 55

Monitoring - mechanical

Answer 55

feeding tube placement
feeding tube patency

Question 56

Special considerations and disease states - acute renal failure

Answer 56

use normal EN formula unless electrolyte profile dictates others
loss of water-soluble micronutrients (selenium, zinc, thiamine)
prealbumin accumulates due to it being cleared renally - falsely high (b/c the kidneys aren’t working)

Question 57

Hemodialysis/continuous renal replacement therapy - CRRT

Answer 57

increased protein requirement to prevent nitrogen deficit (max 2.5 g/kg/day)

Question 58

Hemodialysis/continuous renal replacement therapy - HD

Answer 58

0.8-1.2 g/kg/day protein

Question 59

Special considerations and disease states - hepatic failure

Answer 59

traditional nutritional assessment tools are inaccurate due to presence of ascites, intravascular volume depletion, edema, portal hypertension, and hypo-albuminemia
standard enteral formulations for most liver disease pts: branched amino acid formulations for encephalopathic pts refractory to other treatments

Question 60

Special considerations and disease states - pulmonary failure

Answer 60

fluid-restriction, calorically dense formulations: 1.5-2 kcal/mL
monitor phosphate closely: component of ATP and 2,3-DPG - essential for normal diaphragmatic fx

Question 61

Special considerations and disease states - acute pancreatitis metabolic changes

Answer 61

increase protein catabolism: inability of exogenous glucose to inhibit gluconeogenesis
increase energy expenditure
increase insulin resistance
increase dependence on fatty acid oxidation for energy
EN vs PN: recovery and resumption of oral intake often occurs within 3-7 days, not requiring PN

Question 62

Special considerations and disease states - acute pancreatitis protein requirements

Answer 62

protein requirements: 1.2-1.5 g/kg/day, consider adding glutamine
glucose: safe, same max as other pts
lipid infusions: safe if trigylceride levels are within normal limits –> monitor closely
PN does not affect pancreatic secretion and function

Question 63

Special considerations and disease states - burn

Answer 63

metabolic changes: increased basal metabolic rate and nitrogen loss; glycolysis, proteolysis, lipolysis
nutritional requirements: high in protein (2-2.5 g/kg/day) and calories; early feeding with EN
supplements: adult multivitamin; if TBSA > 10%: ascorbic acid, zinc, vit E, selenium; if TBSA > 20%: oxandrolone/growth hormones; vit D (if deficient), vit A (if on corticosteroids)