Review Notes Flashcards
Routes of feeding
Types of Enteral Formulas
When to use: What are nutritional needs of patient?
* Polymeric (intact Protein)
* Semi-elemental and Elemental (predigested and broken down to facilitate nutrient absorption)
* Specialized formula
Semi- elemental & Elemental EN formulas
protein and lipid predigested and broken down to facilitate nutrient absorption
* Protein; either as smaller peptides or amino acids
* Fat; may contain MCT
* Indication for use: short bowel, severe GI inflammation, liver disease
general guidelines for starting continuous feeds for over 14 years of age
Continuous Feeds:
* Initiate: 0.4-0.5 ml/kg/hr (typically 10-30 mls/hr based
on ASPEN guidelines)
Daily Increases: 0.5-1.0 ml/kg/hr every 24hours (or 0.2-0.3 ml/kg/hr q 8 hrs, or 20-25 ml/hr q 8 hrs).
These are general guidelines to administration; rates of initiation and progression of feeds must be individualized based on the nutritional and medical needs of the patient !!! Note recommended rates may be lower in some patient populations
Energy needs based on kcal/kg
25-35 kcal/kg
* when weight gain not desired (i.e. >75yrs of age), use 25-30kcal/kg
What are the components of energy requirements?
- BMR (basal metabolic requirements)
- Activity (requirements for physical activity)
- Metabolic Stress (requirements related to metabolic stress); note many factors may influence this.
Activity and Metabolic Stress: Impact on Energy Requirements
Need to consider activity levels: in-patient vs. out-patient. Consider Activity Factor (variable)
* 1.0 Bed-rest
* 1.2 Out of bed; very light activity
* 1.3-1.5 Sedentary
* 1.7 Normal Activity
Stress Factors: can have wide range: for cancers often 1.1-1.3; but may be higher.
PN dextrose for adults
Supplies the majority of non-protein calories and osmolality
* Provides 3.4 kcal/g
Typically reported in g/L concentrations on PN bag
* 10% solution = 100 g/L
* 20% solution = 200 g/L
* 30% solution = 300 g/L
* stock solutions of IV dextrose may be as high as 70% as on TPN forms; but can’t deliver this even in central line (it is diluted down to much lower concentrations ie as above)
Delivery
* usually given to patient as a 10% or 20% (but can be a special, for example 17.5%)
* CVL=10-30%
* PIV = anything less than 12.5% w/v (risk of phlebitis and decreased life span of line)
- What is the concentration of D7.5W.
- If you wish to make 1.5 litres of a D7.5W how many kcal would you get??
- 7.5%=75 gm in 1 L.
- 1.5 L=1500 ml =75 g dextrose x 1.5 L=112.5 g dextrose
- In 112.5 g dextrose x 3.4 kcal/g=382.5 kcal dextrose.
GIR calculation
Stress factors
Patients may have ranges of SF based upon the extent of injuries or metabolic changes.
* Skeletal trauma: 1.35
* Major sepsis: 1.6
* Major Head Trauma 1.5
* Minor Operation: 1.2
* Fever/Sepsis: 1.2-1.3 (occ higher) * Severe Burn 2.0
Writing Out TPN order example
Nutrient absorption in jejunum
Intestinal Failure = Malabsorption + Losses
Nutrient absorption in ileum
Intestinal Failure = Malabsorption + Losses
Nutrient balance: Role of the colon
Intestinal Failure = Malabsorption + Losses
Acid Base Balance
Arterial blood gases are critical in the determination: pH, PC02 and HCO3 are important in the definitions.
* Note: pCO2 represents the acid part of the equation. Usually when this increases then pH in blood decreases.
* Bicarbonate represents the base part of the equation (as reflected in the CO2 levels in arterial blood).
* Need PCO2 +pH to calculate bicarbonate (or total carbon dioxide);
* Note pCO2 is not the same as the CO2 concentration; one represents partial pressures; the other actual concentration in blood
Respiratory Acidosis
Primary problem is lung → Low pH and elevated pCO2
* Typically caused by retention of CO2 (retention of CO2 can be caused by problems with ventilation ie decreased respiratory rate due to damage in the lungs, or in CNS). More typical in acute lung failure or acute CNS damage. Note: its typically partial pressures of CO2 that increases
* As pCO2 increase in the blood, H+ are retained within the blood. This results in decreased pH in the blood.
Respiratory Alkalosis
Increased respiration leading to excessive C02 elimination (low pC02 and elevated pH); this results in decreased pC02, and hence decreased H+ ions— leads to an increase in blood pH.
* This may occur when patient experiences lung damage and increasing respiratory rates or possibly when surrounding O2 in environment is decreased.
* In a ventilated patient this may occur when the patient is being weaned off ventilatory support and the O2 is decreased. The patients starts to breath more, but is unable to oxygenate sufficiently.
Waterlow’s Criteria for Classification of Malnutrition
Wasting
- Weight % is much lower than height %ile
- Can be that weight is more than two percentile curves away from height (weight for height)
- Can be that weight is less than 3% ile (weight for age) or is on the 3%ile. But typically weight is at least two centiles below the height centile (and typically weight centile is less than 3- 10%iles)
- Does not have to be both
Stunting
- Height % is much lower than 3 %ile
- Weight for age and weight for height may be fine or they can be low!!
- However, typically height is outside the normal ranges of age appropriate growth (ie less than 3%ile)
Energy & Protein Requirements in Childhood (Enteral) in Healthy Children
Total energy needs
* 100-110 kcal/kg for 0-3 yrs
* 80-90 kcal/kg for 4-6 yrs
* 60-70 kcal/kg for 7-10 yrs
Protein:
* 1.2-1.5 g/kg for 1-3 yrs
* 1.2-1.5 g/kg for 4-6 yrs
* 1.0 g/kg for 7-10 yrs
Peds AF
protein requirements for EN calculations
Fluid in Infants & Children
- An essential component of parenteral nutrition
- Need to consider TFI of pt (total fluid intake)
- Assess other sources of IV fluid, ex maintenance line, meds – does TPN meet req’ts or are other IV’s req’d?
Administration of EN support in infants and children: continuous feeds (over 24 hrs)
energy requirements for PN in children
Growth requirements: Influenced by age, disease type & severity, gender, body composition
* 80-100 kcal/kg; infants < 1 year
* 60-90 kcal/kg for 1-12 years
* 30-60 kcal/kg (adolescents > 12 years)
Guidelines for Administration of Parenteral Dextrose in peds
Guidelines for Administration of Parenteral Amino Acids in peds
Guidelines for Adminisration of Parenteral Lipids
