stress response


stress response

Flight-or-fight response, see there.

stress response

The predictable physiological response that occurs in humans as a result of injury, surgery, shock, ischemia, or sepsis. Synonym: physiological stress response

This response is hormonally mediated and is divided into three distinct phases:

Ebb phase (lag phase): For 12 to 36 hr after the precipitating event, the body attempts to conserve its resources. Vital signs (heart, respiration, temperature) are less than normal. Flow phase (hypermetabolic phase): This stage peaks in 3 to 4 days and lasts 9 to 14 days, depending on the extent of the injury or infection and the person's physical and nutritional status. Carbohydrate, protein, and fat are mobilized from tissue stores and catabolized to meet the energy needs of an increased metabolic rate (hypermetabolism). Serum levels of glucose and electrolytes such as potassium can increase dramatically. If this stage is not controlled by removal of the cause or activator, multiple system organ failure or death can result. Anabolic phase (recovery): The anabolic, or healing, phase occurs as the catabolism declines and electrolyte balances are restored. Aggressive nutritional support is often necessary to promote a positive nitrogen balance.

See also: response