TITLE: METABOLIC STRESS, BURN AND SURGERY AND THEIR NUTRITION THERAPY
PREPARED BY: LEONG SIM KIAN STUDENT NO.10 028112
SUBMITTED DATE: 31 MARCH 2011
In its never-ending quest to maintain homeostasis, the human body responds to stress, physiologic or psychological, with a chain reaction that involves the central nervous system and hormones that affect the entire body. Magnitude and duration of the stress determine just how the body will react. It is important to understand metabolic changes that take place in reaction to stress, both in uncomplicated stress that is present when patients are at nutritional risk, and in more multifarious variations that result from severe stress brought about by trauma or disease. 2
One of the first body functions affected by impaired nutritional status is the immune system. When metabolic stress develops, hormonal and metabolic changes subdue the immune system’s ability to protect the body. This activity is further depressed if impaired nutritional status accompanies the metabolic stress. A deadly cycle often develops: impaired immunity leads to increased risk of disease, disease impairs nutritional status, and compromised nutritional status further impairs immunity. Recovery requires that this cycle be broken.
Trauma from motor vehicle accidents, gunshots, stab wounds, falls and burns is a major cause of death and disability. Unintentional injuries and motor vehicle accidents are ranked as the fifth leading cause of death-after heart disease, malignant neoplasm, cerebrovascular disease and chronic respiratory diseases. Injury results in profound metabolic alterations beginning at the time of injury and persisting until wound healing and recovery is complete. Whether the event is sepsis, trauma (including burns), or surgery, once the systemic response is activated, the physiologic and metabolic changes that follow are similar and may lead to shock and other negative outcomes. Variable responses relate in part to the patient’s age, previous state of health, pre-relate in part to the patient’s age, previous state of health, pre-existing disease, type of infection, and presence of multiple organ dysfunction syndrome (MODS).
The body’s response to metabolic stress depends on the magnitude and duration of the stress. Stress sets up a chain reaction that involves hormones and the central nervous system that affects the entire body. Whether stress is uncomplicated (altered food intake or activity level) or multifarious (trauma or disease), metabolic changes take place throughout the body. According to Gould, the body’s constant response to minor changes brought about by needs or environment were first noted in 1946 by Hans Selye when he described the flight or fight response, or general adaptation syndrome (GAS). The body constantly responds to minor changes to maintain homeostasis. Research following Selye’s work has identified that the stress response involves an integrated series of actions that include the hypothalamus and hypophysis, sympathetic nervous system, adrenal medulla, and adrenal cortex. Significant effects of this response to stress are outlined in Table 1-1. These responses to stress produce multiple changes in metabolic processes throughout the body. The effect of different levels of stress on metabolic rate is illustrated in Figure 1-1.
Table-1-1: Role of Nutrients and Nutritional Status on Immune System Components
Figure 1-1: Percentage of resting metabolic rate. (From Kinney JM et al: Nutrition and metabolism in patient care, Philadelphia, 1988, Saunders.)
If someone must involuntarily go without food, that can be defined as starvation. If we withhold food from ourselves, such as when we try to lose weight, that act can be defined as dieting or fasting. Whatever the cause of inadequate food intake and nourishment, results are...