Lecture Notes: Nutrition and Metabolic Stress

Overview of Metabolic Stress

• Metabolic stressors: Burns, trauma, and surgery.
• Body responses to starvation and metabolic changes during stress.
• Importance of nutrition on immune system function and during malnutrition.

Body's Response to Stress

• Uncomplicated Stress: Nutritional risk without severe complications.
• Severe Stress: Caused by trauma, disease, or surgeries.
• Body’s homeostasis maintenance during stress involves physiological and psychological factors.
• Hormonal and metabolic changes impact the immune system.

Gut Microbiota and Immune System

• Gut microbiota influenced by diet and nutritional status.
• Well-nourished bodies function better immunologically compared to malnourished ones.
• Malnutrition affects skin integrity, mucous membranes, wound healing.
• GI tract changes increase infection risk due to bacterial translocation.

Hormonal Response to Stress

• Involves hypothalamus, sympathetic nervous system, adrenal medulla, and cortex.
• Key stress hormones: aldosterone, anti-diuretic hormone, cortisol, epinephrine, norepinephrine.
• Stress hormones affect heart rate, blood sugar, blood pressure, and energy mobilization.

Starvation vs. Metabolic Stress

• Starvation: Involuntary lack of food intake leading to energy mobilization from stored nutrients.
• Metabolic Stress: Body’s response to maintain energy needs during stress.
• Glycogen, lipids, and protein mobilized during starvation.
• Starvation impacts respiratory function, immune response, and organ systems.

Protein, Carbs, and Fat Metabolism in Stress

• Protein: Increased need; muscle protein mobilized for energy.
• Carbohydrates: Increased glucose production; insulin and glucose levels rise.
• Fat: Mobilized from adipose stores for energy during stress.

Nutritional Requirements During Stress

• Protein: 1.5 to 2 g/kg body weight during severe stress.
• Vitamins and Minerals: Increased need for Vitamin C, A, Zinc.
• Fluid: Adjusted based on age and body composition.

Specific Conditions and Nutritional Management

Surgery and Trauma

• Malnourished patients have higher risk during/after surgery.
• NPO Status: Pre-surgery fasting; post-surgery nutritional intake critical.

Traumatic Brain Injury (TBI) and Spinal Cord Injury

• Hypermetabolism and catabolism significant.
• Swallow evaluation needed; tailored nutritional plans required.

Systemic Inflammatory Response Syndrome (SIRS)

• Triggered by infection, pancreatitis, burns, trauma.
• Increased nutritional needs; early enteral feeding beneficial.

Multiple Organ Dysfunction Syndrome (MODS)

• Failure of two or more organ systems.
• Nutritional support requires increased protein and energy intake.

Burns

• Significant metabolic stress; increased nutritional needs.
• Rule of Nines: Used to assess burn severity.
• Early enteral feeding promotes wound healing.

Additional Key Points

• Importance of adequate nutrition to prevent infections and aid recovery.
• Monitoring and adjusting nutritional intake crucial for effective management of metabolic stress.