Fluid responsiveness in hemodynamically unstable patients: a systematic review

ObjectiveTo evaluate the usefulness of different hemodynamic measurements in the detection of fluid responsiveness (FR) among patients with hemodynamic instability.BackgroundsClose hemodynamic monitoring of unstable patients' response to volume expansion is a central component of intensive care. Previous reports demonstrated that only 50% of patients respond to fluid administration with an increase in stroke volume or cardiac output.Data sourcesA computer literature search of PubMed, Scopus, and Cochrane Central was conducted.Study selectionRecords were screened for eligible studies according to the predetermined inclusion criteria.Data extractionData were extracted and synthesized using standardized tables.Data synthesisData were synthesized qualitatively, and we did not perform a quantitative data analysis.FindingsThe present review included 21 studies of moderate to high quality. All included studies found that CVP does neither correlate with intravascular volume nor accurately predict the FR. The included studies showed significant heterogeneity regarding the predictive value of pulse pressure variation and stroke volume variation. Passive leg raising-induced changes in cardiac output or related parameters were highly predictive for FR.ConclusionThe current literature suggests that the static measures are not reliable indicators of FR. Dynamic indices are of good predictive value regarding FR. In addition, passive leg raising appears to be the most useful test for predicting FR in hemodynamically unstable adults.