Pulse pressure variations adjusted by alveolar driving pressure to assess fluid responsiveness.
OBJECTIVE
To evaluate the ability of DeltaPP/DeltaP [pulse pressure variations (DeltaPP) adjusted by alveolar pressure variations (DeltaP = Pplat-PEEPtot)] in predicting fluid responsiveness, to compare its accuracy to that of DeltaPP used alone and to evaluate the influence of tidal volume (Vt) on these two indices.


METHODS
Prospective study.


METHODS
A 22-bed general intensive care unit (ICU).


METHODS
Eighty-four surgical or medical ventilated patients requiring fluid challenge.


METHODS
A 6 ml/kg colloid fluid challenge in 30 min.


RESULTS
Hemodynamic measurements taken before and after fluid challenge. Patients separated into responders and nonresponders according to a 15% increase in their cardiac output. Thirty-nine patients found to be responders and 45 nonresponders. DeltaPP/DeltaP and DeltaPP were both higher in responders than in nonresponders. DeltaPP/DeltaP was a better predictor of fluid responsiveness than PP, especially for patients ventilated with Vt > or = 8 ml/kg [area under the curve (AUC) 0.88 (0.77-0.98) versus 0.75 (0.60-0.89), P < 0.01)]. In this population DeltaPP/DeltaP higher than 0.9 predicted fluid response with positive predictive value of 87% and negative predictive value of 78%. Overall DeltaPP and DeltaPP/DeltaP reliability was poor for patients ventilated with Vt < 8 ml/kg [AUC 0.63 (0.45-0.81) and 0.72 (0.55-0.88), respectively].


CONCLUSIONS
In this mixed ICU population PP adjusted by P is a simple index which outperforms DeltaPP for patients ventilated with Vt > or = 8 ml/kg. However, correcting DeltaPP by DeltaP still fails to predict fluid response reliably in patients ventilated with low tidal volume.
Pôle Anesthésie et Réanimation, Unité de Réanimation Polyvalente de Purpan, GRCB 48, Université Paul Sabatier, Toulouse, France. vallee.f@chu-toulouse.fr
Fabrice
F
Vallée
Jean Christophe M
JC
Richard
Arnaud
A
Mari
Thomas
T
Gallas
Eric
E
Arsac
Pascale Sanchez
PS
Verlaan
Benjamin
B
Chousterman
Kamran
K
Samii
Michèle
M
Genestal
Olivier
O
Fourcade
D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D003422:Critical Care; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011650:Pulmonary Alveoli / Q000502:physiology*; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000628:therapy; D013990:Tidal Volume / Q000502:physiology