Table 1.

Hemodynamic parameters available today

	Method	Advantages	Disadvantages
Mean arterial pressure (MAP)	Through intraarterial catheter linked to manometer	Easily available	Influenced by many noncardiac factors Contains hardly any information about flow and oxygen transportation
Cardiac output (CO)	Pulmonary artery catheter (PAC), pulse contour analysis	Closely related to oxygen transportation	Demands invasive procedures and/or equipment often not easily available
Cardiac power output (CPO)	The product of MAP and CO	Contains information about both pressure and flow, the total energy transfer from the heart	Demands all the equipment to measure both MAP and CO When using PAC, only available once a minute and difficult to correct for respiratory cycle

We find these parameters insufficiently informative and available.