This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Cardiac Output (CO)
Stroke volume × heart rate – from volumes or from Doppler (VTI × LVOT area)
Scientific basis
What body surface area is needed for
In pediatrics, some drugs – especially in oncology – are dosed not by weight but by body surface area, because metabolism and renal function follow it better than weight. Echocardiographic reference values, renal function (GFR) and the extent of burns are also related to body surface area.
Why the formulas calculate differently
All three formulas are approximations from measurement series in a few individuals. In adults they differ from one another by a few percent, in infants more so – Haycock was specifically tested in children. Which formula a clinic uses is up to the clinic; that is why all three are shown side by side here.
Calculation aid for healthcare professionals: the calculator reproduces what the sources cited assign to the inputs. Clinical assessment and every treatment decision remain with the treating physician. Inputs and results are not stored.
Frequently asked questions
Cardiac Output (CO): What does this calculator compute?
Calculates the cardiac output from stroke volume and heart rate; the stroke volume optionally directly, from EDV and ESV or from the Doppler velocity-time integral (VTI) and the LVOT diameter. With height and weight also the cardiac index and stroke volume index.
Cardiac Output (CO): Which sources is this calculator based on?
Razminia M, Trivedi A, Molnar J, et al.: Validation of new formula for mean arterial pressure calculation: the new formula is superior to the standard formula (Catheter Cardiovasc Interv 63:419–425) (2004); Lang RM, Badano LP, Mor-Avi V, et al.: Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the ASE and EACVI (J Am Soc Echocardiogr 28:1–39) (2015); Lopez L, Saurers DL, Barker PCA, Cohen MS, Colan SD, et al. – American Society of Echocardiography: Guidelines for Performing a Comprehensive Pediatric Transthoracic Echocardiogram: Recommendations From the American Society of Echocardiography (J Am Soc Echocardiogr 37:119–170) (2024); Lopez L, Colan SD, Frommelt PC, et al. – Pediatric Measurements Writing Group, ASE: Recommendations for quantification methods during the performance of a pediatric echocardiogram (J Am Soc Echocardiogr 23:465–495) (2010); Cattermole GN, Leung PY, Mak PS, Chan SS, Graham CA, Rainer TH: The normal ranges of cardiovascular parameters in children measured using the Ultrasonic Cardiac Output Monitor (Crit Care Med 38:1875–1881) (2010); Mosteller RD, N Engl J Med 317:1098: Simplified calculation of body-surface area (1987); Du Bois D, Du Bois EF, Arch Intern Med 17:863–871: A formula to estimate the approximate surface area if height and weight be known (1916); Haycock GB, Schwartz GJ, Wisotsky DH, J Pediatr 93:62–66: Geometric method for measuring body surface area: A height-weight formula validated in infants, children, and adults (1978)