Mechanism of assessmentLimitationsAbility to assess hypervolemia
HR/BP/UOPIndirect measureMany confounding factorsNo
Serum lactateMalperfusion causing anaerobic cellular respirationDecreased clearance in liver diseaseNo
CVPEstimate of right-sided filling pressureMany things falsely elevate CVP including pulmonary HTN and CHFNo
SvO2Measure of oxygen deliverySystemic shunting may falsely elevateNo
PACCardiac filling pressures and thermo-dilutionInvasive. Waveforms subject to interpretationPossibly via elevated PA pressures
PPV/SVVCardiac output variation secondary to the respiratory cycleIrregular HR; low tidal volumes; spontaneous respirationNo
EchocardiographyDirect measure of ventricular filling and cardiac functionImage acquisition and interpretation; learning curvePossible via RV size and lack of change in caval size with respiration
  • BP, blood pressure; CHF, congestive heart failure; CVP, central venous pressure; HR, heart rate; HTN, hypertension; PPV, pulse pressure variation; RV, right ventricle; SVO2, mixed venous oxygen saturation; SVV, stroke volume variation; UOP, urine output.