- Paper Report
- Open Access
Pulse pressure variability as a predictor of volume responsiveness in patients with sepsis
- Ognjen Gajic1
© Current Science Ltd 2000
- Published: 31 August 2000
- pulse pressure
In patients with sepsis it is very important to assess volume status at the bedside. Inadequacies in physical examination have led to widespread use of the pulmonary artery catheter to determine volume status in a critically ill septic patient. Its use, however, has recently come under scrutiny because of a possible association with adverse outcome. In patients on mechanical ventilation, respiratory variations in pulse pressure waveform, as a consequence of changes in pleural pressure, are increased in states of low cardiac preload and tend to decrease with adequate volume resuscitation. The sensitivity and specificity of such testing is unknown, however.
Study group: 40 patients in septic shock on mechanical ventilation with radial and pulmonary artery catheters in place
Hemodynamic measurements: cardiac output was measured by standard thermodilution method
Respiratory changes in arterial pressure: arterial and airway pressures were simultaneously recorded over a period of three breaths. Maximal and minimal values of pulse pressure (Ppmax and Ppmin) and systolic pressure (Psmaxand Psmin) were determined with a single respiratory cycle. The respiratory variations in pulse pressure (δPp) and systolic pressure (δPs) were calculated as the difference between Ppmax and Ppmin divided by the mean of the two values. The results were expressed as percentages
Measurements were repeated before, and 30 minutes after, fluid challenge with 500 cm3 of 5% hetastarch infusion
Sixteen patients had an increase in cardiac output of >15% after the fluid challenge and were considered as responders. Prior to the infusion δPp and δPs were higher in responders than in nonresponders (δPp 24 ± 9 vs 7 ± 3%, P <0.001, δPs 15 ± 5 vs 6 ± 3%, P <0.001). Respiratory change in pulse pressure (δPp) of 13% had a sensitivity of 94% and a specificity of 96% in the prediction of fluid responsiveness. Infusion-induced changes in cardiac output closely correlated with respiratory variation in pulse pressure (δPp) before fluid challenge (r2 = 0.85, P <0.001). Moreover, infusion-induced changes in δPp correlated with infusion-induced changes in cardiac output (r2 = 0.72, P <0.001).
- Michard F, Boussat S, Chemla D, Anguel N, Mercat A, Lecarpentier Y, Richard C, Pinsky MR, Teboul JL: Relation between respiratory changes in arterial pulse pressure and fluid responsiveness in septic patients with acute circulatory failure. Am J Respir Crit Care Med. 2000, 162: 134-138.PubMedView ArticleGoogle Scholar