Interventions

The intervention will consist of attempts to successfully establish a peripheral venous access during the cardiac arrest, and this will happen as soon as possible after the patient has been randomized by opening the randomization envelope. After return of spontaneous circulation (ROSC), modalities on further attempts at establishing vascular access will be at the discretion of the clinician.

The prehospital clinician will be required to attempt the intervention a minimum of two times. One attempt is defined by skin penetration with the peripheral venous catheter (PVC). It will be at the discretion of the clinician to choose anatomical location, whether to use ultrasound or not, and when to abandon the first and second attempt. After the two required attempts with the intervention, the type of vascular access will be at discretion of the clinician.

A successfully established peripheral venous access will be defined by clinical judgement. Signs of a successful peripheral venous access include: 1) backflow of blood into the PVC during placement, 2) no resistance when introducing the catheter into the vein, 3) no resistance to bolus injection, and 4) no infiltration in the surrounding soft tissue after bolus injection. Finally, the clinician may also test whether blood can be aspirated through the PVC.

The intervention will consist of attempts to successfully establish an intraosseous vascular access during the cardiac arrest, and this will happen as soon as possible after the patient has been randomized by opening the opaque envelope. Included patients in this trial arm are further randomized to humeral or tibial access in a 1:1 ratio. After return of spontaneous circulation (ROSC), modalities on further attempts at establishing vascular access will be at the discretion of the clinician.

The prehospital clinician will be required to attempt the intervention a minimum of two times. One attempt is defined by skin penetration with the intraosseous needle. It will be at the discretion of the clinician whether to choose the left or the right bone and when to abandon the first and second attempt but if there is any suspicion of compact bone penetration (as indicated by loss of resistance with the drill) no further approaches towards the same bone should be made. After the two required attempts with the intervention, type of vascular access will be at discretion of the clinician.

A successfully established intraosseous access will be defined by clinical judgement. Signs of a successful intraosseous access include: 1) needle firmly seated in the bone, 2) aspiration of bone marrow, 3) no resistance to bolus injection, and 4) no infiltration in the surrounding soft tissue after bolus injection.