Echo and PAC are not interchangeable cardiac output measurers

thermodilutionState-of-the-art methods and stats on equipment comparison in this depressing study of cardiac output measurement using echo and PA catheter. Even PAC is only moderately precise (?20%). Both clearly suffer from bias, and who knows which is accurate? This is our own ‘measurement problem’, but given what we know about the value of targeting cardiac output, does it matter anyway?