Abstract 96: Continuous Mechanical Chest Compressions During Cardiac Arrest to Facilitate Restoration of Coronary Circulation with PCI. An Experimental, Methodological Pig Study
Background: Coronary heart disease and acute myocardial infarction are the foremost causes of cardiac arrest. Sustained return of spontaneous circulation (ROSC) is often not achieved in these patients due to inability of restoring coronary blood flow during CPR. This might be accomplished if these patients were transported directly to the cath lab for PCI during ongoing mechanical chest compressions. We therefore tested if continuously mechanical chest compressions enabled assessment of the coronary circulation while maintaining an adequate general circulation.
Methods: Five pigs of either sex, weighing 29±3 kg, were anesthetized and tracheally intubated. Arterial circulation was accessed by a cut down to the right femoral artery and a six French sheath was introduced. VF was induced, and continuous mechanical chest compressions with LUCAS (Jolife, Lund, Sweden) started at a rate of 100 min-1. Ventilations were performed manually (10 min-1) with 100% oxygen with a self inflating bag. In order to simulate the transport time to the cath lab an interval of five min of continuous CPR followed. The pigs were randomized to left (n=2) or right (n=3) infarct related artery (IRA), and the non-IRA was first visualized. This was followed by subsequent intubation and visualization of the IRA. Finally, after visualization of the IRA, a balloon was inflated to simulate the revascularization procedure. Thereafter, standard ACLS was continued including DC shocks in an attempt to achieve ROSC.
Results: Continuous CPR with LUCAS was achieved during the PCI procedure; LUCAS was interrupted only once, for 10 sec, in the first pig. Mean arterial pressure during the procedure was 47 mmHg (SD±13 mmHg) Time from VF induction to balloon inflation was mean 12:01 min (range10:01–18:27min). In four pigs sustained ROSC was achieved mean 14:51 min (range 11:20–20:46 min) after VF induction.
Conclusions: Continuous mechanical chest compressions with LUCAS during cardiac arrest enabled assessment of the coronary circulation and the potential for PCI in an attempt to restore coronary blood flow. This could be an alternative approach in cardiac arrest patients with suspected myocardial infarction who do not achieve ROSC.