Monday, August 26, 2019


Q: Pulse Pressure Variation (PPV) - an indicator of intravascular volume responsiveness is an unreliable indicator in patients with intra-abdominal hypertension (IAH)? (select one)

A) True
B) False

Answer: B

Pulse pressure is simply a difference between the systolic and the diastolic arterial blood pressure. Variation in pulse pressure (PPV) averaged over three or more breaths can be calculated by the formula

PPV = 100 x (PPmax – PPmin)/PPmean 

Many commercially available devices calculate it when an arterial line is present. PPV of 10 to 15 percent is found to be strongly associated with volume responsiveness, particularly in mechanically ventilated patients. 

It was postulated that raised IAH will distort PPV and will not be a reliable indicator of volume responsiveness in an intravascularly "dry" patient. But, studies have shown that PPV stays reliable despite IAH.



1. Marik PE, Cavallazzi R, Vasu T, Hirani A. Dynamic changes in arterial waveform derived variables and fluid responsiveness in mechanically ventilated patients: a systematic review of the literature. Crit Care Med 2009; 37:2642.

2. De Backer D, Heenen S, Piagnerelli M, et al. Pulse pressure variations to predict fluid responsiveness: influence of tidal volume. Intensive Care Med 2005; 31:517.

3. Renner J, Gruenewald M, Quaden R, et al. Influence of increased intra-abdominal pressure on fluid responsiveness predicted by pulse pressure variation and stroke volume variation in a porcine model. Crit Care Med 2009; 37:650.

4. Jacques D, Bendjelid K, Duperret S, et al. Pulse pressure variation and stroke volume variation during increased intra-abdominal pressure: an experimental study. Crit Care 2011; 15:R33.

No comments:

Post a Comment