Metabolic Response to Trauma and Sepsis

Vocabulary flashcards covering the metabolic, physiological, and systemic responses to trauma and sepsis, including mortality peaks, SIRS, sepsis stages, and phases of metabolic response.

First Peak of Fatalities

The initial peak of trauma deaths occurring in the first hour after injury, where survival can generally only be increased by preventative measures.

Second Peak of Fatalities

The peak of trauma deaths occurring within $1\text{--}4\text{ hours}$ after injury, accounting for approximately $30\text{\%}$ of trauma fatalities, generally caused by haemorrhage, and constituting the majority of preventable deaths.

Third Peak of Fatalities

The peak of trauma deaths occurring days to weeks after injury, resulting from infection and multiorgan failure.

Metabolism

The complex system of interrelated biochemical reactions and physiological responses required to maintain life.

Stress Response

The body's damage control system, triggered by stimuli such as traumatic injuries and sepsis, intended to maintain homeostasis on a cellular and systemic level and to provide substrate for injury repair.

Systemic Inflammatory Response Syndrome (SIRS)

The pathological extension of the stress response involving hormonal and inflammatory signals that produce a hyperdynamic and hypermetabolic state.

Sepsis

A condition defined as the presence of two or more Systemic Inflammatory Response Syndrome (SIRS) criteria combined with a confirmed or suspected infection.

Severe Sepsis

A stage of sepsis characterized by sepsis accompanied by signs of end organ damage.

Septic Shock

Severe sepsis accompanied by persistent hypotension with a systolic blood pressure (SBP) $< 90\text{ mmHg}$ or lactate $> 4\text{ mmol}$.

Ebb Phase

The early shock phase occurring within the first $24\text{ hours}$ of injury, characterized by hypovolaemic hypoperfusion, reduced energy expenditure, decreased metabolism, decreased urine output, and decreased blood pressure, resulting in a cold, hypotensive state.

Flow Phase

The catabolic phase occurring days to weeks after injury, characterized by a hyperdynamic state, high metabolic rate, elevated cardiac output, breakdown of proteins and fats, weight loss, hyperglycaemia, lipolysis, fever, and tachycardia.

Anabolic Phase

The convalescent or recovery phase occurring weeks after injury, during which resynthesis of lost tissue, rebuilding of protein and fat stores, and weight gain take place.

Primary Hormonal Mediators

Glucagon, cortisol, and catecholamines, which serve as the main hormonal signals driving the metabolic stress response to trauma and sepsis.