A 3-month-old is brought to the emergency department with fever and symptoms of shock. What is the priority intervention for this patient?

The priority intervention for a 3-month-old exhibiting fever and symptoms of shock is to infuse a rapid 10-20 mL/kg bolus of an isotonic crystalloid. In pediatric patients, especially infants, shock can lead to significant complications quickly due to their smaller blood volume and rapid changes in hemodynamics.

The main concern in a child presenting with shock is restoring adequate perfusion and maintaining blood pressure, which is essential for ensuring that vital organs receive enough oxygen and nutrients. The rapid infusion of isotonic crystalloid solutions, such as normal saline or lactated Ringer's solution, is an immediate and effective way to expand intravascular volume, improve circulation, and stabilize the patient while further assessments and treatments are being initiated.

This approach addresses the immediate threat of hypovolemia or poor perfusion that can accompany febrile illnesses, especially in young children, and takes precedence over other treatments such as administering antipyretics, initiating antibiotic therapy, or using vasoactive medications. These options may be part of the broader treatment plan but do not address the critical need for volume resuscitation in an acute shock scenario.