ASPEN ch 14--PN overview Flashcards
why crystalline a.a. better?
better utilized and lack preformed ammonia
3-in-1 also called ____ admixture
total nutrient
PN is hypertonic to body fluids and can result in _______ if admin inappropriately
venous thrombosis, suppurative thrombophlebitis, extravasation
osmolarity of PN formula primarily depend on these components:
dextrose (5mOsm/g), a.a. (10mOsm/g), electrolytes (1mOsm/g)
max osmolarity of PPN:
900mOsm
CPN often referred to as:
total parenteral nutr
why can handle greater osmolarity in CPN?
rate of blood flow in large vessels rapidly dilutes hypertonic formulation to that of body fluids, minimize risk of complications
PPN used up to ____ days
14
why PPN undesirable for pt on fluid restriction?
large fluid vols needed because can’t concentrate solution too much
why limit PPN?
tolerance limit, few suitable veins
for PPN must meet these 2 criteria:
good peripheral venous access and able tolerate large volumes of fluid
__ may be used to ^ energy density of PPN without increasing osmolarity, can improve vein tolerance of PPN:
ILE
use of ___ catheters recommended in pt needing PPN>6 days
midline (lower probability dislodge)
contraindications to PPN:
significant malnutrition, severe stress, large nutr/electrolyte needs, fluid restriction, prolonged PN need, renal/liver probs
____ concept is relevant to critically ill pt who don’t tolerate nutr (esp PN) well
permissive underfeeding
why permissive underfeed?
intended minimize complications of PN delivery by providing only 80% of est. energy requirements until condition improves
___ feeding used in both EN and PN for obese to meet pro rqts but provide less nrg than estimated rqt
hypocaloric
why use hypocaloric feed?
minimize metabolic complications of PB while improve N balance
___ PN is approach designed to minimize energy deficit accumulated during period of no nutrition/undernutrition
supplemental
indications for PN:
unable meet nutr rqts with EN, PPN up to 2 wks when pt can’t ingest/absorb PO or EN or when CPN not feasible, CPN necessary when >2wks and peripheral access limited/nutr needs large/fluid restrict
use CPN when:
pt failed EN trial, EN contraindicated cuz of underlying condition, duration of starvation unknown and can’t tolerate EN/PO, clinical conditions
PN should only be initiated if pt is ____ stable and can tolerate doses
hemodynamically
when PN needed in pancreatitis, recommended that PN energy admin not exceed _____kcal/kg/d and glucose controlled
25-35
why glutamine recommended in PN for pancreatitis?
minimize effect of being NPO on GI integrity
how can surgery aggravate malnutrition?
stress produce proinflamm cytokines, ^ metabolic rate and catabolism, v LBM and aberrant glycemic control
ratio of ___ to ___ may predict diminishing inflamm
prealbumin; CRP
critical illness characterized by:
catabolic state result of SIRS to infectious/traumatic insult
why gut failure common in critical ill?
preferential blood supply to vital organs
why EN benefit in critically ill?
positive impact on immune barrier and decreasing permeability of GI tract to orgs (v inflamm); low risk of mesenteric ischemia when introducing EN
critically ill pt needing PN fit this criteria:
malnourished at baseline, not reliably ingest EN for >7-10 days, adequately resuscitated from hemodynamic compromise (also if paralytic ileus, acute bleeding, bowel obstruction)
most PN errors occur during ____ and ___ phase
transcription; admin
how to decrease error?
multistep double check process, multidisciplinary teams
PN should only be advanced when this criteria met:
stable BP, pulse, resp rates; normal electrolytes and glucose
to prevent rebound hypoglycemia, PN should be ___ over 1-2 hours
tapered
