Which event marks the transition to the catabolic phase?

Which event marks the transition to the catabolic phase?

• A. Resuscitation
• B. Onset of fever
• C. Onset of infection
• D. Initiation of nutrition support

Answer: (A)

In metabolic response to critical illness, the body moves from an initial resuscitation (ebb) phase to a sustained, hypermetabolic catabolic phase once perfusion and stabilization are achieved. Resuscitation marks that switch because it ends the low-flow, conservation state and sets the stage for energy mobilization that fuels vital organs, leading to increased proteolysis, gluconeogenesis, and lipolysis. Fever or infection reflect inflammatory processes that accompany illness but don’t indicate the transition point itself. Initiation of nutrition support is a response during the catabolic phase to supply substrates for repair, not the event that initiates the shift.

In metabolic response to critical illness, the body moves from an initial resuscitation (ebb) phase to a sustained, hypermetabolic catabolic phase once perfusion and stabilization are achieved. Resuscitation marks that switch because it ends the low-flow, conservation state and sets the stage for energy mobilization that fuels vital organs, leading to increased proteolysis, gluconeogenesis, and lipolysis. Fever or infection reflect inflammatory processes that accompany illness but don’t indicate the transition point itself. Initiation of nutrition support is a response during the catabolic phase to supply substrates for repair, not the event that initiates the shift.