stress and critical care part 1

critical illness

person who has sustained an acute, life threatening illness or injury

hyper metabolism, wasting, life-threatening complications

what are the 3 effects of metabolic and respiratory stress?

10 days

when does resting metabolic rate (RMR) peak after injury?

Ebb, flow catabolic, flow anabolic

what are the 3 phases of injury?

sepsis, trauma, burns, major surgery, stress, fractures

what causes a hyper metabolic responses?

Ebb phase

shock resulting in hypovolemia, decreased oxygen availability to tissues, decreased cardiac and urinary output

flow phase

hyper-metabolism, catabolism, altered immune and hormonal response

recovery phase

return to anabolism

2-48 hours

how long does Ebb phase last?

3-10 days

how long does catabolic flow state last?

10-60 days

how long does anabolic flow state last?

ebb phase

maintenance of blood volume; low BMR, O2 consumption, vasoconstriction; increase CO2, HR, acute phase proteins

catabolic flow

maintenance of energy; increased BMR, temp., O2 consumption, -n2 balance

anabolic flow

replacement of lost tissue; positive n2 balance

hormones

stress and injury activate fight or flight ______.

epi., norepi., glucagon, cortisol

what are the fight or flight hormones?

mobilize nutrients to meet immediate demand, glucagon GNG, glycogenolysis, beta oxidation, cortisol- GNG and FA metabolization

what do the f/f hormones do?

floods system with glucose, could lead to hyperglycemia

what is the end result of f/f hormones?

amino acids- glutamate and alanine. skeletal muscle.

in GNG, what do we use as de novo glucose precursors? What is broken down to make this happen?

insulin therapy

common in critical care settings regardless of DM status

140-180 mg/dL

what is the glucose goal range in critical care?

negative

______ nitrogen balance is a consistent marker of metabolic stress.

anabolism, building muscle

what does positive nitrogen balance mean?

catabolism, losing muscle

what does negative nitrogen balance mean?

nitrogen input - nitrogen output - 4

what is the nitrogen balance equation?

6.25

1 gram of nitrogen = ______ grams of protein

higher % lean body mass lost = higher associated mortality %

how does lean body mass relate to mortality?

protein and energy production abnormal, no adaptive response available, increase metabolic rate 35-40 kcal/kg/day, increase glucose production more than need, increase use of protein for fuel, increased levels of fight/flight hormones, hyperglycemia, insulin resistance, increased BMR, increased rate of GNG, catabolism of skeletal muscle, increased urinary nitrogen excretion/negative nitrogen balance

what happens with catabolic insult-induced protein-energy malnutrition?

infections, sepsis

what are the risks of EN/PN in critical care?

en

______ is preferred- more cost effective, no difference in outcomes between EN and PN

24-48

initiate EN within ______ hours of admission when patient is hemodynamically stable and at nutritional risk.

vitals are normal

what does hemodynamically stable mean?

valid, reliable

many standard assessments for nutritional assessment are not ________or_______ in this population.

data, patient status, tolerance

re-evalaution of ___, _____, and ______ is a necessity in the critically ill population.

medical and social history, food-nutrition related history, anthropometrics, NFPE

what are the main components of the assessment?

APACHE II Score/SOFA score, risk of referring syndrome, medications/propofol, biochemical data/medical tests

what are the critical care specific parts of assessment?

acute physiology and chronic health evaluation (APACHE) score

predicts patient mortality risk

nutric score of NRS-2002

combines measures of metabolic stress and injury with nutrition parameters; allows RDN to identify individuals with risk of malnutrition. 0(normal)-3(severe) scores.

cytokines

proteins that, in small amounts, affect behavior or other cells and, in larger amounts, can exert systemic effects

tumor necrosis factor alpha (TNF-a)

if high, you know altered metabolism: catabolism (AA loss, increase use of AA and increased lipolysis), hyper-metabolism, fever.

interleukin-1 (IL-1)

fever, increased acute phase protein synthesis

IL-6, IL-8, IL-12

activation and release of cellular communication/mediators (APP synthesis, fever)

interferon-y

damage to respiratory monocytes (immune cells)

acute phase proteins

protein that increase (positive) or decrease (negative) during inflammatory disorders

indirect calorimetry

gold standard got energy needs

12-25 kcal/kg actual BW

kcals for ICU for 7-10 days

25-30 kcal/kg actual BW

kcals for BMI 20-25

11-14 kcal/kg IBW

kcals for BMI 30-501

22-25 kcal/kg IBW

kolas for BMI >50

mifflin st jeor, peen state 2003, schofield

what are the 3 equations used for kcal needs?

obesity, mechanical ventilation, stress, trauma, paralytic drugs

what factors impact energy estimations?

increased CO2 production, hyperglycemia

what are the subsequent metabolic effects of overfeeding that require you to avoid overfeeding?

1.2-2.0 g/kg actual BW

what are the protein needs for BMI 20-29?

2 g/kg IBW

what are the protein needs for BMI 30-40?

2.5 g/kg IBW

what are the protein needs for BMI >40?

1.5-2.0 g/kg actual BW

what are the protein needs for burns?

2.2 g/kg

potentially poorer outcomes of ________ in preexisting kidney disease and acute kidney injury. mo re research is needed.

metabolic stress

assessment of visceral protein status are typically more reflective of the level of ______ than the patient actual protein status and are affected by fluid balance, wound losses, and use of blood products.

albumin, prealbumin

caution against using ______ and _______ to measure protein status.

APP

liver prioritizes the synthesis of ______ during stress and the synthesis rates of other proteins are down regulated.

lactate

elevated _____ levels are na indication that aerobic metabolism is unregulated and can be a sign of tissue perfusion. can also contribute to positive anion-gap metabolic acidosis.

slow, gradual

if vasopressors are low (0.3 mcg/kg/min), a ________, ______ increase in EN is needed.

gut perfusion

why does EN need to be slowly titrated if pressers are on board?

aspiration, delayed GI motility, frequent inability to reach goal volume

what are some barriers to EN?

should

feeding into the stomach is appropriate. If tolerant, feeding post-pyloric _____ be used.

24-hour volume

_________ feeding may be helpful are feedings are often inconsistent and stopped.

7

if unable to meet goal kcal intake, supplemental PN should be intimated after ____ days.

combination feeding protocol

a combination of EN, PN, and PO is commonly used in the ICU and is called…

standard polymeric formula

what is the formula recommendation?

immune-modulating

__________ nutrients have mixed results in critical care. Suggested to be reserved for special cases (SICU, perioperative, burns, TBIs)

glutamine (non-essential AA)

preferred fuel for enterocytes and assists in maintaining intestinal membrane permeability, supports immune cell growth, reduced pro-inflammatory cytokines, precurso for glutathione (antioxidant)

arginine (AA)

precursor for nitric oxide, levels may be inadequate during metabolic stress because unavailability of precursors (glutamine and citrulline)

nitric oxide

involved in vessel dilation, stimulation of hormone release, signaling an deregulation of neurotransmitters

antioxidant

______ depletion may occur to mitochondrial dysfunction and oxidative stress.

omega-3 FAs

______- can reduce pro-inflammatory cytokines involved in systemic inflammatory conditions and metabolic stress

fiber

sources of _____ to EN can provide substratees that assist in maintenance of beneficial bacteria in the gut.

soluble fiber

is diarrhea develops, ______ can be used. caution in hemodynamically unstable or severe dysmotility.