Mid-arm circumference. Estimating patients' weight.

Calculation of drug dosages and intravenous fluids rates are often based on the patient's weight. However, in many critical care situations either time cannot be spared to weigh the patient or the equipment is too cumbersome to use. Too often the patient's weight is estimated by guessing. This article explores the development of a rapid, easy, portable, and objective method for estimating weight based on mid-arm circumference (MAC).