Accurate weights are an essential component of managing a critically-ill pediatric patient. All critical care medications are weight-based, thus small inaccuracies in estimated weight can significantly impact medication efficacy. Much literature has been devoted to the accuracy of guessing weights in pediatric patients and the conclusion remains the same: guessing weight based on perceived age is not accurate.

Length-based resuscitation tools, such as the Broselow tape, are more accurate if used correctly. Providers must follow the instructions very closely and ensure that the end of the tape is pulled up to the top of the child’s head. Even these simple instructions can be misapplied, so careful interpretation of the tape is warranted. The Broselow tape demonstrates close agreement with actual weight but is least accurate when the child is over 25 kg, so if the child’s length is near the end of the tape, assume that the weight may be less accurate. Also body habitus must be taken into account, as obesity levels remain high in American children. Some other weight estimation systems may outperform the Broselow tape; however, despite the chosen method, they all outperform guessing the weight. Do not guess the weight!