Parenteral and Enternal Nutrition - Lecture 3 Flashcards
EN - if the ____ works, use it
gut
EN indications
oral consumption inadequate
oral consumption contraindicated: esophageal obstruction, head and neck surgery, dysphagia, trauma, cerebrovascular accident, dementia
Advantages of EN
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
Decreased bacterial translocation leads to
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
Contraindications to EN
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
Routes of administration for EN
nasogastric/orogastric (can put meds down)
nasojejunal/orojejunal
gastrostomy: PEG
jejunostomy; PEG/PEJ
Determining route of access
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
Confirm proper placement
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
Methods of administration
bolus, intermittent, continuous infusion, trickle or trophic
Bolus
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
Bolus advantages and disadvantages
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
Intermittent
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)
Continuous infusion (most common in hospital)
administer continuously over 12-24 hrs/day
requires use of infusion pump
preferred method when feeding into jejunum
Continuous infusion advantages and disadvantages
advantages: lower risk of gastric distention and aspiration; better tolerated by pt
disadvantages: problematic for med administration; requires infusion pump
Trickle or trophic
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
Initiation and advancement of tube feeding
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)
Cyclic
administer over 8-10 hrs/day
often infused overnight
advantage: increased independence for pt
EN - ICU initiation points
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
NPO times
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
Formula selection
pt characteristics: functional capacity of GI tract, underlying disease, nutritional requirements
formulary availability
Formula examples
jevity, impact 1.5, glucerna, nepro
higher the # of kcal/mL or protein = more concentrated (can give more calories with less volume)
Immune-modulating contents (impact 1.5)
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
Target pt populations with impact 1.5
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
EN nutrient composition - protein
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
EN nutrient composition - fat
long-chain fatty acids
medium chain fatty acids: more water soluble; rapid hydrolysis, little or no pancreatic lipase for absorption
EN nutrient composition - carbohydrates
glucose polymers primarily used for tube feeding formulas
simple glucose used for oral supplements (higher in osmolality)
Adjunctive therapies
can give these with tube feeds
modular supplements
glutamine
probiotics
vitamins and trace elements
Modular supplements - most common
pro-stat: category - protein
15g protein
72 kcal
3g CHO
Other modular supplements
nutrisource, fiber, benefiber: category - fiber
juven: category - wound care, HIV/AIDs, cancer
glutasolve: category - glutamine (for burn pts)
Glutamine
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)
Probiotics
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)
Vitamins and trace elements
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
Complications
gastrointestinal
metabolic
mechanical
medication-related
Complications - gastrointestinal
high gastric residuals
aspiration
nausea/vomiting or decreased motility: consider prokinetic medications; metoclopramide, erythromycin may be given
abdominal distention
diarrhea
constipation
High gastric residuals
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
Aspiration risk reduction
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
Decreased motility: consider prokinetic agents
metoclopramide
erythromycin
naloxone (if given enterally, doesn’t affect pain meds)
methynaltrexone
Diarrhea
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
Complications - metabolic
hype- or hypoglycemia: check meds, insulin regimen, stress, infection
overhydration; dehydration: monitor fluid status
electrolyte imbalance: hyponatremia most common
Glyemic control in ICU
goal blood glucose = </- 180 mg/dL
NICE-SUGAR study found increased mortality and higher rate of hypoglycemia with tight blood glucose control
Complications - Mechanical
clogging of feeding tube
tube malposition (abdominal x-ray (KUB))
rhinitis: reposition daily, use smaller bore tube, change from NG to OG
sinusitis
Complications - medication related
clogged feeding tubes
drug-tube feed interactions
General guidelines for medication delivery via enteral feeding tubes
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
Liquid medications preferred
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
Do not crush list
delayed/extended release
enteric coated
buccal or sublingual
carcinogenic, teratogenic, cytotoxic
+/- capsules (if you can open, ok to give)
Clogged feeding tubes
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
Unclogging the tube
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
Drug/tube feed interactions - antibiotics
fluroquinolones, itraconazole solution, tetracyclines, penicillin V
Drug/tube feed interactions - anti-retrovirals
didanosine
dolutegravir
indinavir
Drug/tube feed interactions - other
levothyroxine, phenytoin, theophylline, warfarin
Drug/tube feed interactions - what to do
hold tube feed –> wait 1 hr –> give med –> wait 2 hrs –> resume tube feed
Monitoring
gastrointestinal
metabolic
mechanical
Monitoring - gastrointestinal
gastric residuals
emesis
check q4-6hrs
stools daily: frequency of stools, volume of stools
bloating/distention
bronchial/tracheal aspirate
Monitoring - metabolic
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
Monitoring - mechanical
feeding tube placement
feeding tube patency
Special considerations and disease states - acute renal failure
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)
Hemodialysis/continuous renal replacement therapy - CRRT
increased protein requirement to prevent nitrogen deficit (max 2.5 g/kg/day)
Hemodialysis/continuous renal replacement therapy - HD
0.8-1.2 g/kg/day protein
Special considerations and disease states - hepatic failure
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
Special considerations and disease states - pulmonary failure
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
Special considerations and disease states - acute pancreatitis metabolic changes
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
Special considerations and disease states - acute pancreatitis protein requirements
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
Special considerations and disease states - burn
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)
