Table 4.

Survival by patient characteristics, bystander response, and LAS treatment for exercise SCA

Variable	Died		Survived
	N	Per cent	N	Per cent
Age	–	–	–	–	χ2=5.91, df=7, p=NS
Initial rhythm					χ2=17.49, df=2, p<0.001
VF/VT	35	55	29	45
Asystole	22	100	0	0
PEA	8	89	1	11
Bystander CPR					χ2=3.25, df=1, p<0.1
Yes	35	61	22	39
No	30	79	8	21
Pre-LAS defibrillation					Fisher's exact test: p<0.05
Yes	1	17	5	83
No	64	72	25	28
LAS defibrillation					χ2=4.85, df=1, p<0.05
Yes	43	61	27	39
No	22	92	3	8
Advanced airway management*					χ2=24.03, df=1, p<0.001
Yes	62	82	14	18
No	3	18	14	82

*Patient received intubation and/or a supraglottic airway; use of intubation was not recorded for two patients, these cases have been excluded from this analysis.

LAS, London Ambulance Service; PEA, pulseless electrical activity; SCA, sudden cardiac arrest; VF/VT, ventricular fibrillation/ventricular tachycardia.