Transcript Energy- & Protein-Modified Diets for Metabolic & Respiratory Stress

Energy- & Protein-Modified Diets
for Metabolic & Respiratory
Stress
Chapter 24
Nutrition & Diet Therapy, 7th Edition
Stress in the Body
• Body’s response to severe stress can threaten
survival
• Stress increases nutritional needs
considerably—increasing risk of malnutrition
• Metabolic stress: disruption of body’s internal
chemical environment
• Respiratory stress: characterized by
inadequate oxygen supply & excessive carbon
dioxide in blood & tissues
• Both types of stress can lead to
hypermetabolism, wasting & life-threatening
complications
Nutrition & Diet Therapy, 7th Edition
I. Body’s Response to Stress &
Injury
• Stress response: non-specific response of
the body to variety of stressors (ex. infection,
fractures, surgery, etc.)
• Metabolic processes focus on immediate
survival
– Energy nutrients mobilized from storage &
made available in the blood
– Energy is diverted from non-essential
processes (like growth…)
– Heart & respiratory rates increase to deliver
oxygen & nutrients to cells
– Long-term stress results in damage to body
processes due to diversion of energy, nutrients
to organs needed for survival
Nutrition & Diet Therapy, 7th Edition
Nutrition & Diet Therapy, 7th Edition
Body’s Response to Stress &
Injury
• Inflammatory response
– Quick, non-specific immune system
response to infection or tissue injury
– Contains & destroys infectious agents &
their agents; prevents further tissue
damage
Classic Signs of Localized
Inflammation
Swelling
Redness
Heat
Pain
Nutrition & Diet Therapy, 7th Edition
Inflammatory Response
Nutrition & Diet Therapy, 7th Edition
Body’s Response to Stress &
Injury
• Systemic effects of
inflammation
– Acute-phase response:
changes in body chemistry
resulting from
inflammation, infection or
severe injury
• Release of acute-phase
proteins & blood clotting
proteins
• Decreased plasma
concentrations of
albumin, iron & zinc
• Muscle catabolism &
negative nitrogen balance
• Elevated metabolic rate,
increased numbers of
neutrophils
• Lethargy, anorexia
• Fever
Nutrition & Diet Therapy, 7th Edition
• Systemic inflammatory
response syndrome and
sepsis-long term
– Whole-body response to
unresolved inflammation or
infection
• Increased heart rate &
respiratory rate
• Elevated WBC levels
• Critical elevation of body
temperature
– Complications
• Excessive fluid retention &
tissue edema
• Low blood pressure
• Impaired blood flow
• Can lead to shock—affecting
functioning of multiple organs
II. Nutrition Treatment in
Acute Stress
• Determining nutritional
requirements
– Major metabolic changes
in metabolic stress
•
•
•
•
Hypermetabolism
Negative nitrogen balance
Hyperglycemia
Insulin resistance
– Feeding patient during
acute stress presents
challenges
• Overfeeding increases
risks of refeeding
syndrome
• Underfeeding worsens
negative nitrogen balance
& increases lean tissue
losses
Nutrition & Diet Therapy, 7th Edition
Refeeding
syndrome—develops
when malnourished
individual is
aggressively fed;
associated with fluid
& electrolyte
imbalances;
hyperglycemia
Nutrition Treatment in Acute
Stress
• Determining nutritional requirements (con’t)
– Nutritional assessment
• Complicated by fluid imbalances & lab data
• Amounts of pro & E to provide are controversial (p.660, T.
24-2 provide guidelines)
• Assortment of medical conditions that cause metabolic
stress makes each situation unique
• Clinicians must observe patient’s responses & readjust
nutrient intakes as necessary
– Estimation of protein needs
• Intakes recommended during acute stress are higher than
DRI values
• Variable needs, but range between 1.0-2.0 grams per kg
body weight daily (burn patients require more, 2-2.5 g/Kg,
due to significant protein losses)
• Glutamine & arginine supplementation may be indicated,
studies still being done.
Nutrition & Diet Therapy, 7th Edition
Nutrition Treatment in Acute
Stress
• Determining nutritional requirements (con’t)
– Carbohydrate & fat
• Bulk of energy needs are supplied by carbohydrate & fat
– 50-60% total kcalorie intake from carbohydrate sources
– Fat intake (if patient does not have hypertriglyceridemia) may
be 1-1.5 grams per kg daily
– Frequent assessment of nutritional needs necessary
– Micronutrients: h need for B,C, & A vits, Zn
• Approaches to nutrition care
– Initial care—maintain fluid & electrolyte balances w/IV
– Once feeding begins—combination of methods to meet
nutritional needs
– Nutritional support as warranted
• Enteral nutrition preferred
• Parenteral nutrition if adequate nutrient intakes cannot be
provided from enteral feedings alone
Nutrition & Diet Therapy, 7th Edition
III. Nutrition & Respiratory
Stress
• Chronic obstructive pulmonary disease
(COPD)
– Group of conditions characterized by persistent
obstruction of airflow through the lungs
• Chronic bronchitis
• Emphysema
– Both conditions reduce capacity of lungs to
maintain normal oxygen & carbon dioxide
levels in the blood
– Shortness of breath (dyspnea) occurs
– May lead to respiratory or heart failure
– 4th leading cause of death in U.S.
Nutrition & Diet Therapy, 7th Edition
Nutrition & Diet Therapy, 7th Edition
Nutrition & Respiratory
Stress
• COPD (con’t)
– Debilitating condition
• Dyspnea generally worsens as condition progresses
• Results in dramatic reductions in physical activity &
quality of life
• Associated with other chronic illnesses, anxiety,
depression & psychological distress
– Causes
• Smoking tobacco is primary risk
• Genetic susceptibility contributes to development,
especially in patients with early-onset COPD
Nutrition & Diet Therapy, 7th Edition
Nutrition & Respiratory
Stress
• COPD (con’t)
– Treatment
• Primary objectives of
treatment: prevent
disease from
progressing & relieve
major symptoms
• Smoking cessation
• Influenza &
pneumonia
vaccinations
• Medications
– Bronchodilators
– Corticosteroids
Nutrition & Diet Therapy, 7th Edition
• Nutrition
– Promote maintenance of
healthy body weight &
prevent muscle loss
– Improve food intake
– Small, frequent meals
– Adequate fluid intake
– High-kcalorie, high-protein
diet if undernourished
– Liquid supplements to
improve weight gain or
exercise endurance
– E-restricted diet for gradual
weight loss if overweight or
obese
– Specialized formulas
– Incorporating exercise
program
Nutrition & Respiratory
Stress
• Respiratory failure
– Gas exchange between air & circulating blood
becomes greatly impaired
– May develop from chronic disease (ex., COPD)
or acute respiratory failure
– Various factors affecting lung function may
contribute to cause
– Acute respiratory distress syndrome (ARDS)
• Acute form of respiratory failure, life threatening
• Commonly triggered by severe trauma or infection
Nutrition & Diet Therapy, 7th Edition
Nutrition & Respiratory
Stress
• Respiratory failure
(con’t)
– Consequences
• Low blood levels of
oxygen (hypoxemia) &
excessive carbon
dioxide in blood
(hypercapnia)
– Acidosis
– Increased
respiratory rate
– Cyanosis (blue skin),
other symptoms
• Inadequate oxygen
supply to tissues
(hypoxia)
Nutrition & Diet Therapy, 7th Edition
– Treatment
• Focuses on supporting
lung function & correction
of underlying disorder
• Treatment plan depends
on specific disorder
– Oxygen therapy
– Mechanical ventilation
– Monitoring & supporting
fluid balance
– Diuretics
– Medications to treat
infection, keep airways
open, relieve
inflammation
• Mechanical ventilation controls the rate &
amount of O2 supplied to a person’s
airways
Nutrition & Diet Therapy, 7th Edition
Nutrition & Respiratory
Stress
• Respiratory failure (con’t)
– Nutrition therapy
• Individualized, based on patient’s condition
– Provide enough E & protein to support lung function;
increased cal, but not excessive as this generates extra
CO2 and may increase respiratory problems.
– Fluid restrictions to help reduce pulmonary edema
• Enteral feeding preferred over parenteral nutrition
– Nutrition support
• Tube feedings are used if intestinal tract is functional
– Intestinal feeding preferred over gastric
– Nutrient-dense formula (2 kcalories per mL, less fld. needed)
• Parenteral nutritional support may be necessary if risk
of aspiration is too high to continue enteral feedings
Nutrition & Diet Therapy, 7th Edition
Nutrition in Practice—Multiple
Organ Failure
• Also referred to as multiple organ dysfunction
syndrome
– Late stage of severe illness or injury that results from severe
inflammatory response
– Failure of 2 or more of body’s organ systems
– Involves lungs, liver, kidneys, GI tract
– Involvement of 3 or more organs is associated with fatality rate
of almost 100%
• Cause
– Systemic inflammatory response syndrome (SIRS)
• Normal adaptive response to severe insult
• Can progress to shock, resulting in impairment of numerous
organ systems
• Risk Factors: Age, Severity of SIRS, Infection, Blood transfusion
Nutrition & Diet Therapy, 7th Edition
Nutrition & Diet Therapy, 7th Edition
Nutrition & Diet Therapy, 7th Edition
Nutrition in Practice—Multiple
Organ Failure
• Treatment
– Lung support
– Fluid resuscitation
– Support of heart & blood vessel function
– Kidney support
– Reversal or prevention of infection
– Nutrition support
Nutrition & Diet Therapy, 7th Edition