Association of transcranial Doppler blood flow velocity slow waves with delayed cerebral ischemia in patients suffering from subarachnoid hemorrhage: a retrospective study

Intensive Care Medicine Experimental

Table 2 Temporal and spatial differences of measured variables across the overall study population

Variables	Side of measurement	Time of measurement (pre-VS)	Time of measurement (during VS)	p value
CBFV (cm/s)	Ipsilateral	89.6 ± 22.5	156.2 ± 23.7	< 0.001
	Contralateral	78.9 ± 31.4	100.5 ± 43.7	0.92
CBFV SWs	p value	0.94	0.17
[cm/s]	Ipsilateral	2.86 ± 1.21	4.15 ± 1.55	< 0.001
	Contralateral	2.89 ± 1.48	3.29 ± 1.30	0.95
Tau	p value	0.92	0.17
[s]	Ipsilateral	0.25 ± 0.17	0.17 ± 0.08	0.19
	Contralateral	0.28 ± 0.16	0.19 ± 0.09	0.83
Mxa	p value	0.98	0.97
	Ipsilateral	0.24 ± 0.20	0.31 ± 0.21	0.16
	Contralateral	0.20 ± 0.18	0.23 ± 0.26	0.92
SampEn	p value	0.95	0.8
	Ipsilateral	2.67 ± 0.93	3.00 ± 0.96	0.83
	Contralateral	2.95 ± 1.32	3.16 ± 2.15	0.83
	p value	0.95	0.95

N = 32, two-way ANOVA, post hoc comparisons, SPSS Sidak adjusted p values
VS vasospasm, Tau time constant, CBFV cerebral blood flow velocity, SWs slow waves, Mxa mean autoregulatory velocity index, SampEn sample entropy