In shock with poor perfusion, what is the initial fluid resuscitation volume?

• A. 5 mL/kg isotonic crystalloid
• B. 10 mL/kg isotonic crystalloid
• C. 20 mL/kg isotonic crystalloid
• D. 40 mL/kg isotonic crystalloid

Answer: (C)

In shock with poor perfusion, the priority is to rapidly restore intravascular volume to improve preload and cardiac output. Isotonic crystalloids are chosen because they expand the circulating volume quickly and are well tolerated.

The initial resuscitation volume is 20 mL/kg. This amount is large enough to promptly boost perfusion but not so large as to overwhelm the patient or cause unnecessary edema before reassessment. Smaller doses (5–10 mL/kg) are often insufficient to reverse shock promptly, while a very large bolus (around 40 mL/kg) increases the risk of fluid overload and related complications.

After giving 20 mL/kg, reassess perfusion (blood pressure, heart rate, capillary refill, urine output, mental status). If there is persistent hypoperfusion, you may repeat boluses or escalate therapy as guided by the patient’s response.