Evaluation of remote ischaemic post-conditioning in a pig model of cardiac arrest: A pilot study.

Background: Remote ischaemic post-conditioning (RIPoC) in which transient episodes of ischaemia (e.g. by inflation and deflation of a blood pressure cuff) are applied after a prolonged ischaemia/reperfusion injury, may have the potential to improve patient outcome and survival following cardiac arrest. In this study we employed a pig model of cardiac arrest and successful cardiopulmonary resuscitation to evaluate the effects of RIPoC on haemodynamics, cardiac tissue damage and neurologic deficit.

Materials And Methods: A total of 22 pigs were subjected to ventricular fibrillation, cardiopulmonary resuscitation and randomly assigned to Control or RIPoC treatment consisting of 4 cycles of 5 min femoral artery occlusion followed by 5 min of reperfusion starting 10min after return of spontaneous circulation (ROSC). Post-resuscitation was evaluated by haemodynamics using left ventricular conductance catheters, quantification of cardiac troponin T (cTnT), lactate dehydrogenase (LDH) and creatine kinase (CK). Neurological testing was performed 24h after return of spontaneous circulation (ROSC).

Results: RIPoC resulted in a statistically significant reduction of serum cTnT levels 4h after ROSC (P ≤ 0.01). LDH and CK concentrations were significantly lower in RIPoC treated pigs 24h after ROSC (P ≤ 0.001), suggesting tissue and/or cardioprotective effects of RIPoC. End-systolic pressure volume relationship was significantly increased in RIPoC treated animals 4h after ROSC (P ≤ 0.05). Neurological testing revealed a trend towards an improved outcome in RIPoC treated animals.

Conclusions: We propose that RIPoC applied immediately after ROSC reduces serum concentrations of markers for cell damage and improves end-systolic pressure volume relationship 4h after ROSC.