For burn casualties, a TBSA greater than what percentage indicates the need for fluid resuscitation?

• A. 10%
• B. 15%
• C. 20%
• D. 25%

Answer: (C)

When a burn involves a substantial portion of the body, the body’s fluid balance is severely disrupted by capillary leak and third-spacing. About twenty percent TBSA is the tipping point at which these fluid losses become large enough that simple wound care and oral fluids aren’t enough, so intravenous fluid resuscitation is needed to maintain perfusion and prevent hypovolemic shock. In adults, twenty percent TBSA is the standard trigger to start resuscitation, typically guided by a crystalloid like lactated Ringer’s using a formula such as Parkland (4 mL per kg of body weight per percent TBSA burned, with half given in the first eight hours and the rest over the next 16 hours), while monitoring urine output to ensure adequate circulation. Burns smaller than this threshold often don’t require aggressive IV fluids beyond maintenance, which is why twenty percent is the key benchmark for initiating resuscitation.