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 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 Nutrition & Diet Therapy, 7th Edition

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 Refeeding syndrome—develops when malnourished individual is aggressively fed; associated with fluid & electrolyte imbalances; hyperglycemia Nutrition & Diet Therapy, 7th Edition

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 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 & Diet Therapy, 7th Edition

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) 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 Nutrition & Diet Therapy, 7th Edition

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