Burn shock is a severe condition resulting from major burns, characterized by decreased cardiac output, increased vascular resistance, hypovolemia (low blood volume), and hypoperfusion (inadequate blood flow to tissues). It's crucial to understand that burn shock isn't simply a single stage but rather progresses through distinct phases.
The Two Phases of Burn Shock
According to multiple sources, burn shock physiology is divided into two main phases:
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Emergent Phase (also known as the acute or ebb phase): This initial phase is characterized by significant fluid loss from the burned area and subsequent hypovolemia. This leads to decreased cardiac output and impaired tissue perfusion. The body's initial response is aimed at combating this fluid loss and preserving vital organ function. Examples include the release of hormones to try and maintain blood pressure. This phase is critical and requires immediate medical intervention.
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Flow Phase (also known as the hypermetabolic or flow phase): This later phase, following fluid resuscitation, is characterized by increased metabolic demands and ongoing capillary leak. While the immediate threat of hypovolemia is addressed through fluid resuscitation, the body continues to struggle with maintaining adequate tissue perfusion due to ongoing fluid shifts and increased cellular demands. This phase necessitates ongoing monitoring and supportive therapy.
Understanding the Severity
The severity of burn shock depends on factors such as the extent and depth of the burn, the patient's age and overall health, and the effectiveness of treatment. Burns covering more than 20% of the total body surface area (TBSA) are often associated with the development of burn shock. Early recognition and aggressive treatment are critical for improving outcomes.
