Updated Nutr 408 Unit 3 MNT in Critical Care

Metabolic response to stress occurs in response to

Sepsis
Trauma
Burns
Surgery

Catabolism of lean body mass

Negative nitrogen balance
Muscle wasting

Ebb phase

Hypovolemia
Shock
Tissue Hypoxia
Decreased oxygen consumption
Decreased cardiac output
Decreased body temperature

Flow Phase Definition

After fluid resuscitation and oxygen

What occurs in Flow Phase

Increase oxygen consumption
Increased cardiac output
Increased body temperature
Release of pro-inflammatory cytokines

What Hormones Released during the stress response

Catecholamines
Glucagon
Cortisol
Aldosterone
Antidiuretic Hormone

Metabolic Effects of Catecholamines

Increase in metabolic rate
Glycogen breakdown in liver and muscle
Glucose production from amino acids
Release of fatty acids from adipose tissue
Glucagon secretion from pancreas

Metabolic Effects of Glucagon

Glycogen breakdown in liver
Glucose production from amino acids
Release of fatty acids from adipose tissue

Metabolic Effects of Cortisol

Protein degradation
Enhancement of glucagon's action on liver glycogen
Glucose production from amino acids
Release of fatty acids from adipose tissue

Metabolic Effects of Aldosterone

Sodium reabsorption in kidneys

Metabolic Effects of Antidiuretic Hormone

Water reabsorption in kidneys

Metabolic Response to Starvation

Decreased blood glucose
Increased insulin, increased glucagon
Glycogen depletion
Gluconeogenesis
Ketosis
Decreased energy expenditure

Systemic Inflammatory Response Syndrome is associated with

sepsis

Systemic Inflammatory Response Syndrome characteristics

High or low body temperature
Increased heart rate and respiratory rate
High or low white blood cell count
Multiple organ dysfunction syndromes (MODS)
Edema
Low Blood pressure and impaired blood flow

Systemic Inflammatory Response Syndrome

Shock results in gut hypo-perfusion

Illeus

Paralyzed GI tract

Paralyzed GI Tract

No motility
Typically shuts down temporary
Cannot feed in GI tract, No oral or enteral nutrition

Early enteral feeding

Restores gut function and reduces bacterial translocation

EN preferred over PN due to

decreased risk of infection and stress response

PN lipids are

pro-inflammatory

Nutrition assessment in the ICU: usually unable to obtain

Diet History
UBW
Height
Allergies

How to find information that you are unable to obtain?

Call family/caregivers
Measure height
Most hospital beds have scales

Why are the bed scales NOT accurate?

Not an accurate way to assess weight due to pillows, blankets, and fluid overload/hydration status

Weight can be affected by

Fluid resuscitation

Plasma proteins low due to

Injury, illness, inflammation, and fluid overload

Recommended BG level:

140 to 180 mg/dl
Patients typically hyperglycemic

In ICU, If BS less than 180

it is typically considered well controlled

What to focus on in ICU

Focus on prior nutrition status

What should you focus on with prior nutriton status?

When to feed, how to feed, depend on nutrition status prior to admission

MNT for Starved or Stressed Patients should avoid overfeeding as it may result in

Refeeding syndrome
Fluid overload
Hyperglycemia
Difficulty weaning from vent
Hepatic Steatosis

Refeeding syndrome

Aggressive administration of nutrition to malnourished patient
Glucose moves into cells for oxidation, which causes electrolytes to shift into intracellular space
Electrolyte Imbalance

Why is fluid overload bad?

rapid weight gain

What is the issue with difficulty weaning from vent

High CO2

Hepatic Steatosis

fatty liver

MNT for SIRS and MODS: Energy

Use indirect calorimetry or Penn State equation

Which way to assess Energy needs is gold standard?

indirect calorimetry

Why would you use Penn State Equation?

Enter ventilation settings to give you a better estimate of energy expenditure

Nonvent kcals/kg/d

25 to 30 kcals/kg/d

Why avoid overfeeding with non vent?

due to excess CO2 production

On vent kcals/kg/d

20-25 kcals/kg/d

When assessing energy needs for SIRS and MODS what weight do you want to use?

Use dry weight

Hypocaloric feeding for obese patients

BMI: 30-50: 11-14 kcals/kg/d
BMI: >50: 22-25 kcals/kg/d IBW

Protein Needs for SIRS and MODS

Depends on baseline nutrition status, degree of injury, losses
1.2 to 2 g/kg/d

For Protein, what should you focus on incorporating in diet for MODS and SIRS

Glutamine
Arginine
BCAAs

Why BCAAS

important for protein synthesis, any complete
protein should have BCAAs
Can be metabolized in muscles
Used as direct fuel source

Fat Needs for MODS and SIRS

Omega 3 Fatty Acids because they're antiinflammatory

What is the method to feed fat to patients?

Oral feeding if able

What is the rule of thumb for feeding Fat with MODS and SIRS

EN if NPO with good intestinal function
PN only if EN is contraindicated
PN also if they're on NPO > 7 days

For Total Parental Nutrition Less than 4 weeks (short-term) use

Naso tube
Ex. Nasogastric, Nasoduodenal, Nasojejunal

For Total Parental Nutrition More than 4 weeks use

ostomy tube
Ex. Gastrostomy tube or jejunostomy tube

ostomy tube

Opening from stomach

Any stomach condition or pancreatitis warrants

J tube feeding

Peripheral Parental Nutrition Only infuse

dextrose amino acids, not lipids

Why limit dextrose to put in formula

because it might blow up vein

The only maconutrient need you can meet with PPN is

protein

Why can't you do PPN for longterm?

you can't provide adequate nutrition

PIC Line - Peripheral Inserted Catheter

Only in icu
Inserted in arm but it threaded all the way through to the vena cava
Used for Long term

Timing of Nutrtion Support initiation depend on

Length of NPO status
Based on if patients need to be on oral feeding for more or less than 7 days

<7 days to oral feeding for patients that are Adequately nourished provide them with

Dextrose containing IVF

For adequately nourished patients, If NPO > 7 days or if there is a change in clinical status

then begin nutrition status

What requirements make some adequately nourished

• premorbid BMI >18.5 BMI and <10% weight loss

For Malnoursihed patients that require <7days of oral feeding, you should begin

nutrition support

Criteria for Malnourished nutrition support patients

Pre-mornbid BMI

Enteral Nutrition associated with

Reduced disease severity
Decreased Length of stay in ICU
Decreased infection rate
Decreased mortality

Goals for Enteral Nutrition

Minimize starvation
Correct nutrient deficiencies
Provide adequate energy
Fluid and electrolyte management
Reduces oxidative stress
Modulate immune response

With EN, must first establish

hemodynamic stability

What is hemodynamic stability

Maintenance of airway/breathing
Adequate circulating fluid volume and tissue oxygenation
Acid-base neutrality

What to monitor for EN

Heart rate
Blood pressure
Mean arterial pressure (MAP)
Use of pressors - dopamine, epinephrine, norepinephrine
Oxygen saturation

Enteral Nutrition Start within

24-48 hours of ICU admission

Enteral Nutriton advance to goal during

next 48-72 hours

What percent of goal calories should you hit during first week of Enteral Nutrition

50-65%

Enteral Nutriton: Monitor for tolerance

Pain/distension
Gastric residual volume (GRV)
Aspiration
Passage of flatus/stool

Enteral Nutrition: to improve tolerance

Elevate the head of the bed
Post-pyloric tube placement
Pro motility medication
If the patient is having diarrhea, recommend an anti-diureal
Lower/slow tube feeding rate

Post-pyloric tube placement

Moving place of tube feeding
Place the tube in the jejunum instead

What pro motility medication to recommend

reglan

Formula Selection: Immune modulation for GI surgery, trauma, and burns

arginine, glutamine, antioxidants, omega-3
These all help the body heal and good for immune system

Why Arginine

prevents losses of lean body mass

Why Glutamine

important for immune system

Key ingredients to improve tolerance

elemental, low fat, low fiber, hypo osmolar formula

Appropriate candidates for Parenteral Nutrition

Impaired GI absorption or loss of nutrients
Bowl obstruction
Need for bowel rest
Motility disorders
Enteral access not possible

When to initiate parenteral nutrition

after 7 days for well-nourished pts
Within 3-5 days for mild to moderate malnutrition
ASAP for moderate to severe malnutrition

Consider Supplemental PN after

7-10 days of not meeting 60% of needs with EN

Major Burns Characterized by

Increased energy expenditure
Protein catabolism
Susceptibility to infection

Major burns medical management

Fluid and electrolyre repletion
Wound care
ROM exercises
Warm environment
<20% TBSA burned: high-kcal, high-protein, high-fluid diet

Major Burns: May need nutrition support if

unable to meet nutritional needs with oral diet

MNT for Major Burns: Energy

Use indirect calorimetry (IC) and increase by 10-30%
Predictive equaition of IC not available
Prevent > 10% weight loss from UBW

MNT for Major Burns: Protein

1.5-2 g/kg/d
Depends on nitrogen balance and PAB

MNT for Major Burns: Micronutrients

Vitamin C
Zinc

Which of the following occurs during the ebb phase of injury?

Hypovolemic shock

During the ebb phase of hypermetabolic response, hypovolemia, shock, and tissue hypoxia occur

immediately after injury.

The acute response of the flow phase to these physiologic changes during the Ebb phase of injury includes

release of catecholamines and other hormones that promote an increase in metabolic rate and hyperglycemia

Which of the following may have a role in supporting tight junctions between the intraepithelial cells in the gut?

Enteral feedings

Lack of nutrition or parenteral nutrition may be contributing factors to

loss of the tight junctions.

Nitrogen balance is used to monitor

protein metabolism

Which of the following statements is not true about cortisol?

It promotes hypoglycemia

Cortisol, which is released from the adrenal cortex in response to stimulation by adrenocorticotropic hormone secreted by the anterior pituitary, enhances

skeletal muscle catabolism and promotes hepatic use of amino acids for gluconeogenesis, glycogenolysis, and acute-phase protein synthesis.

What is generally observed during stress.

Hyperglycemia

In critically ill patients, what is the recommended range for maintaining serum glucose?

140 to 180 mg/dl