Table 4.

Comparison between 2011–2021 and 2000–2010 decades regarding the modality of fluid challenge administration

General characteristics	2011–2021	2000–2010	p value
Fluid responders (%)	52 (45–60)	52 (43–62)	0.32
Crystalloids versus colloids (n. of studies)	57 versus 32	11 versus 20	0.007
Volume (ml)	500 (500–500)	500 (500–500)	0.32
Time of infusion (min)	15 (10–30)	30 (15–30)	0.03
Threshold 10% versus 15% (n. of studies)	30 versus 62	6 versus 26	0.17
CO/CI versus SV/SVI (n. of studies)	61 versus 30	18 versus 12	0.51

CO, cardiac output; CI, cardiac index; SV, stroke volume; SVI, stroke volume index