Changes in the mean systemic filling pressure during a fluid challenge in postsurgical intensive care patients
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The difference between mean systemic filling (Pmsf) and central venous pressure (CVP) is the venous return gradient (dVR). The aim of this study is to assess the significance of the Pmsf analogue (Pmsa) and the dVR during a fluid challenge.
We performed a prospective observational study in postsurgical patients. Patients were monitored with a central venous catheter, a LiDCO™plus and the Navigator™. A 250-ml intravenous fluid challenge was given over 5 min. A positive response to the fluid challenge was defined as either a stroke volume (SV) or cardiac output increase of greater than 10 %.
A total of 101 fluid challenges were observed in 39 patients. In 43 events (42.6 %) the SV and CO increased by more than 10 %. Pmsa increased similarly during a fluid challenge in responders and non-responders (3.1 ± 1.9 vs. 3.1 ± 1.8, p = 0.9), whereas the dVR increased in responders (1.16 ± 0.8 vs. 0.2 ± 1, p < 0.001) as among non-responders CVP increased along with Pmsa (2.9 ± 1.7 vs. 3.1 ± 1.8, p = 0.15). Resistance to venous return did not change immediately after a fluid challenge. Heart performance (Eh) decreased significantly among non-responders (0.41 ± 0.15 vs. 0.34 ± 0.13, p < 0.001) whereas among responders it did not change when compared with baseline value (0.35 ± 0.15 vs. 0.34 ± 0.12, p = 0.15).
The changes in Pmsa and dVR measured at the bedside during a fluid challenge are consistent with the cardiovascular model described by Guyton.
KeywordsFluid challenge Goal-directed therapy Preload Mean filling pressure Venous return
- 12.Anderson RM (1993) The gross physiology of the cardiovascular system. Racquet, TucsonGoogle Scholar
- 17.Lakhal K, Ehrmann S, Runge I, Benzekri-Lefevre D, Legras A, Dequin PF, Mercier E, Wolff M, Regnier B, Boulain T (2010) Central venous pressure measurements improve the accuracy of leg raising-induced change in pulse pressure to predict fluid responsiveness. Intensive Care Med 36(6):940–948PubMedCrossRefGoogle Scholar
- 21.Kumar A, Anel R, Bunnell E, Habet K, Zanotti S, Marshall S, Neumann A, Ali A, Cheang M, Kavinsky C, Parrillo JE (2004) Pulmonary artery occlusion pressure and central venous pressure fail to predict ventricular filling volume, cardiac performance, or the response to volume infusion in normal subjects. Crit Care Med 32(3):691–699PubMedCrossRefGoogle Scholar