Capillary refill time is most reliable in assessing end-organ perfusion in children under what age?

Capillary refill time is a useful assessment tool for evaluating peripheral perfusion and is particularly important in children, where it can help identify potentially serious conditions like shock. In young children, their capillary beds are more reactive, and the significance of capillary refill time is more pronounced.

Research and clinical guidelines suggest that capillary refill time is most reliable in children under 6 years of age. This is because younger children have a higher baseline metabolic rate and differ developmentally from older children, making them more susceptible to changes in circulation and perfusion that can be detected by observing capillary refill.

While the exact age range can vary based on clinical context, the general consensus in pediatric emergencies is that after the age of 6, the reliability of capillary refill as an indicator of end-organ perfusion begins to diminish as they approach adult physiology. In this context, the answer indicating that under 6 years old (specifically 6 years) provides the most accurate assessment aligns with established pediatric assessment practices.