Table 2.

Spearman correlation coefficients between neuromonitoring-derived parameters and hemodynamic indices before and after PLR

Neuromonitoring parameters	Hemodynamic indices
	CI	SVI	MAP
Before PLR test
ICP	− 0.01	0.32	− 0.08
CPP	− 0.08	− 0.39	0.38
PRx	− 0.07	0.10	− 0.27
SpO2	0.03	− 0.08	0.05
rSO2	0.25	0.02	− 0.23
O2Hbi	0.04	− 0.11	0.36
Hhbi	0.15	0.24	0.08
cHbi	0.22	0.18	0.24
After PLR test
ICP	− 0.09	0.21	− 0.34
CPP	0.09	− 0.23	0.70***
PRx	− 0.29	0.02	− 0.40*
SpO2	− 0.08	0.12	0.21
rSO2	0.17	− 0.25	0.06
O2Hbi	− 0.03	− 0.14	− 0.07
Hhbi	− 0.07	0.11	− 0.32
cHbi	− 0.01	− 0.17	− 0.38

PLR passive leg raising, SVI stroke volume index, CI cardiac index, ICP intracranial pressure, MAP mean arterial blood pressure, CPP cerebral perfusion pressure, PRx pressure reactivity index, SpO₂ systemic oxygen saturation, rSO₂ regional cerebral saturation, O₂Hbi oxygenated hemoglobin, Hhbi deoxygenated hemoglobin, cHbi total hemoglobin; *p < 0.05; **p < 0.01; ***p < 0.001