PURPOSE OF THE STUDY
To determine the time “call-first shock” in OHCA in our units and to study time intervals involved in it: “call-dispatch”, “dispatch-monitor on”, “monitor on-first shock”.

MATERIAL AND METHODS
To determine the time “call-first shock” in OHCA in our units and to study time intervals involved in it: “call-dispatch”, “dispatch-monitor on”, “monitor on-first shock”.

RESULTS
1706 OHCA registered: 126 (7.38%) meet inclusion criteria.
Mean interval between call and shock is 14 m 42 s (DS=385 s).
Using Tanigawa’s intervals our findings show:
Delay over 13 m is 51,6%, being lower than 9 m in 14.3% of cases.
Delays bigger than 20 min are just 13.5%.
Mean interval between call and ALS team dispatch is 2 m 15 s (SD=78 s).
Mean interval between ALS team dispatch and when the monitor is switched on is 10 m 21 s (SD=343 s).
Mean interval between “monitor switched on” and the first shock is 2 m 8 s. (SD=68 s).

CONCLUSIONS
- OHCA have specific difficulties that imply delays in the first shock delivery (patients hard to reach, excess of clothes, unsafe area) that have to be studied. 
- Our intervals “call-first shock” seem to be better than in other published studies.
- Interval variability can be due to the absence of a fixed procedure regarding the moment to turn the monitor on in our units.
- Rates of time “monitor on-shock” higher than two minutes have to be studied further.

3 - First shock delays in out-of-hospital cardiac arrest