Primary objectives:~In adult and paediatric patients with Out-of-Hospital Cardiac Arrest (OHCA) in Singapore, investigators aim to evaluate the incremental benefit of introducing a resuscitation protocol including the use of intravenous (IV) access and/or intraosseous (IO) vascular access compared to protocols with only intravenous (IV) access by SCDF paramedics in the pre-hospital setting on the return of spontaneous circulation (ROSC) rates.~Secondary Objective:~To compare the success rates of vascular access with IV access and/or IO insertion compared to that with intravenous (IV) access alone by SCDF paramedics in the pre-hospital setting.~To compare the rates of successful 1st dose adrenaline given in the field to cardiac arrest patients in IV+IO and IV groups and whether this translates into a higher survival rate at 30 days.~To determine the cost benefit of introducing IO access to the emergency ambulance service for OHCA.~Hypothesis:~In adult and paediatric patients with Out-of-Hospital Cardiac Arrest (OHCA) in Singapore, the hypothesis is that low vascular access rates could be due to difficulty of setting IV cannulas in the field due to certain factors like poor lighting or space constraints. Thus, by introducing a protocol including IO access for difficult IV cases, success rates for vascular access will be higher and this might lead to a higher ROSC and survival rates.
In patients with out-of-hospital cardiac arrest in Singapore, investigators aim to assess the benefit of introducing a resuscitation protocol including the use of intravenous (IV) access and/or intraosseous (IO) vascular access in the pre-hospital setting.~The assumption is that low vascular access rates could be due to difficulty of setting IV cannulas in the field due to certain factors like poor lighting or space constraints. Thus, by introducing a protocol including IO access for difficult IV cases, success rates for vascular access will be higher and this might lead to higher survival rates.~This will be a study comparing 'IV+IO' and 'IV alone' protocols in patients with cardiac arrest managed by Singapore Civil Defence Force (SCDF) emergency ambulance service. The trial will recruit 400 patients over 1 year. Each of the 30 SCDF ambulances will provide both 'IV+IO' and 'IV alone' treatments in 2 consecutive phases of 6-months in order to allow for all ambulance crew a chance to be trained on usage of IO. Currently, IO insertion is the accepted standard of care in Singapore General Hospital, Department of Emergency Medicine.