- Normal = 6 - 12 mm Hg; (
Swan Ganz) - in absence of pulmonary HTN, > 10 cm
PEEP, or mitral valve dz, it reflects left atrial Pressure (
Preload), and is measured after inflation of the balloon, which allows the tip of the catheter to wedge in a capillary; - in absence of obstruction of mitral valve (
MS) wedge pressure also approximates the mean left ventricular diastalic pressure; - however, in presence of elevated left ventricular end diastolic pressure (height of ventricular filling pressure just before ventricular contraction) caused either by an increase in end diastolic volume or a decrease in left ventricular
Compliance, the wedge does not accurately reflect the left ventricular end- diastolic pressure, which may significantly exceed mean wedge; - height of the
pulmonary wave or the pulmonary capillary a wave is the most consistent accurate indirect index for sudden changes in actual left ventricular end diastolic pressure; - nevertheless, the wedge reflects mean left ventricular diastolic pressure and is therefore a useful index to estimate not only the possible risk of the development of pulmonary edma, but also left ventricular
Preload; - in critically ill patients, ventricular
Compliance is altered, and there may be no correlation between pressure and volume, making it impossible to estimate left ventricular
Preload from the wedge; - by optimizing the
PCWP according to the patients individual Starling curve, opitimal
Cardiac Output; -
PCWP < 6, think low LVEDP (
Preload), in relatively healthy heart,
CO may be increased by expanding the volume;
PCWP > 12, in absence of severe cardiac dz, means pulmonary congestion due to fluid overload or CHF; - long standing Cardiac disease may shift the Starling Curve to left; - consequently, a significantly elevated
PCWP may be required to optimize
CO; - patients s/p MI may need
PCWP of 16-18 to optimize CO; - when PCWP is > 12 mm, then
CO may be optimized w/
dobutamine and/or
dopamine; - use mean pressure reading to best approx L.A. pressure; - use the pressure inbetween respirations; - filling pressures should be read just before Inspiration; - high
PEEP may falsely elevate Wedge Pressure; (subtract 1/3 of PEEP value from wedge for more accurate pressure) ----------------
A noninvasive method of predicting pulmonary-capillary wedge pressure 
