<prompt> Direct Fick method of measuring cardiac output requires estimation ofO2 content of aerial bloodO2 content of venous bloodO2 consumption per unit timeAll of the above  <response>: Applying Fick;s principle Output of left ventricle Cardiac output O2 consumption mLmin - Therefore this method requires the following valuesO2 consumption per unit timeAerial O2 content Venous o2 contentRef: Ganongs Review of Medical Physiology Twenty-Third Edition Page No:513 