In heat exhaustion, what is the IV fluid bolus protocol?

• A. 2000 mL
• B. 1000 mL
• C. 500 mL
• D. NS or LR bolus 500 mL IV/IO; repeat to SBP >90; max 2000 mL

Answer: (D)

In heat exhaustion, the goal is to restore circulating volume safely with crystalloids while avoiding fluid overload. The recommended approach is to give a normal saline or lactated Ringer’s bolus of 500 mL IV or IO, then reassess the patient. If the systolic blood pressure remains below about 90, you repeat another 500 mL bolus, continuing in these 500 mL increments until perfusion improves (SBP > 90) or you reach a cumulative maximum of 2000 mL. This stepwise method ensures you deliver enough fluid to improve hypotension without exposing the patient to excessive total fluid too quickly. The 2000 mL cap helps prevent overload, particularly in patients with potential cardiac or renal issues.