TABLE 1.

Comparison of clinical and electrophysiological characteristics between the two groups.

	Bad neurological outcome (n = 23 unless otherwise specified) (/29)	Good neurological outcome (n = 6) (/29)	p
Age (years), mean ± SD [min-max] Median [IQR 25–75]	60 ± 16 [24–87] 62 [54–68.5]	47.5 ± 16 [26–64] 52.5 [34.75–59]	0.07
Male, n	20	5	1
Shockable rhythm*, n	6	2	1
Etiology  Cardiac  Non-cardiac  Undetermined	10 12 1	4 2 0	0.57
No-flow (minutes), mean ± SD Median [IQR 25–75]	8.3 ± 8.4 (/21) 7 [1–15]	2.7 ± 4.3 0 [0–4.5]	0.07
Low-flow (minutes), mean ± SD Median [IQR 25–75]	24.9 ± 16.4 20 [18.5–35]	16.4 ± 11.7 15.5 [10.75–21]	0.22
Time to ROSC (≤25 min), n	8 (/21)	4	0.20
GCS on admission /15), mean ± SD Median [IQR 25–75]	3.1 ± 0.4 3 [3–3]	3.5 ± 1.2 3 [3–3]	0.21
SAPS II score, mean ± SD Median [IQR 25–75]	73 ± 15 72 [63–85]	62.5 ± 18 54 [49–76]	0.15
Sedation, n	8	3	0.65
EEG Grade I: predominant alpha with some theta, n	0	1
EEG Grade II: predominant theta with some alpha, n	0	0
EEG Grade III: predominant theta, n	3	5	0.0002
EEG Grade IV: delta activity, n Generalized epileptiform periodic activity (GPEDs), n	7 6	0 0
EEG Grade V electrocerebral silence, n Burst suppression patterns, n	3 4	0 0
EEG reactivity, n	3	2	0.27
SSEP (N20 -), n	7 (/22)	1/5	0.64
AEP (MMN+), n	4	2	0.57
GOS-E (6 months) (n)	3 (1/23)	4–8 (5/6)

*As the first documented rhythm; ROSC, return of spontaneous circulation; GCS, Glasgow Coma Scale; SAPS II score, simplified acute physiology score II; EEG, electroencephalography patterns according to the five major grades of severity scale for brain injury; SSEP, cortical somatosensory evoked potentials; AEP, auditory evoked potentials; MMN, mismatch negativity. No-flow data were missing in two patients and SSEP (N20 response) data in one patient (underlying Charcot Marie Tooth disease). GOS-E, Glasgow Outcome Scale-Extended.