Measurement of cardiac output by thermal dilution in infants and children.

The accuracy of the thermal dilution technique for measuring cardiac output in infants and children has been assessed by comparison with the direct Fick technique. Satisfactory correlation between the two methods has been demonstrated, and it is concluded that a commercially available monitor can be used to determine cardiac output by thermal dilution in acutely sick infants and children. The volume of injectate should be selected according to the weight of the child, and the value displayed by the monitor should be adjusted by the appropriate fraction.