Bailey & Love - Chapter 1: Metabolic Response to Injury

Metabolic Response to Injury

• The body's systemic changes in response to significant local tissue injury are referred to as the metabolic response to injury.
• The mediators involved in the metabolic response to injury include neurohormonal responses, such as cortisol and catecholamines, which trigger various pathways, including the hypothalamic-pituitary-adrenal (HPA) axis and the sympathoadrenal system.
• Prolonged abnormal processes during the metabolic response to injury can lead to complications, such as multi-organ dysfunction syndrome (MODS) and death.

Aims and Goals

• The main aim of the body's metabolic response to injury is to maintain homeostasis and promote recovery by mobilizing energy stores and directing energy towards the vital organs.

Surgical Involvement

• Surgeons are inextricably linked with the metabolic response to injury, as they often trigger the surgical stress response, which leads to a systemic inflammatory response.
• The surgical stress response can lead to further tissue damage and organ dysfunction.

Physiological Phases

Catabolic Phase

• The main physiological role of the catabolic phase is to mobilize energy stores and direct energy towards the vital organs.
• The catabolic phase is characterized by a breakdown of tissues, such as muscle wasting and fat metabolism.
• The systemic response triggered by the neurohormonal responses in the catabolic phase is the systemic inflammatory response.

Homeostasis

• The concept related to maintaining a constant internal environment for optimal cellular function is homeostasis.

Anabolic Phase

• The anabolic phase primarily focuses on rebuilding and repairing tissues.
• A consequence of the catabolic effects of injury is a negative nitrogen balance, which can lead to muscle wasting and decreased immune function.

Critical Care

• In modern surgical care, the role of surgical critical care during the metabolic effects of injury is crucial in preventing complications and promoting recovery.
• Successful management of the metabolic response to injury improves patient outcomes, including reduced morbidity and mortality rates.

Trauma Care

• In modern treatment of major trauma, the majority of hospital deaths in developed countries occur during the anabolic phase, which can last for weeks or even months after the initial injury.