Sodium nitroprusside enhanced cardiopulmonary resuscitation (SNPeCPR) improves vital organ perfusion pressures and carotid blood flow in a porcine model of cardiac arrest

Abstract

Purpose of the study To describe a new method of CPR that optimizes vital organ perfusion pressures and carotid blood flow. We tested the hypothesis that a combination of high dose sodium nitroprusside (SNP) as well as non-invasive devices and techniques known independently to enhance circulation would significantly improve carotid blood flow (CBF) and return of spontaneous circulation (ROSC) rates in a porcine model of cardiac arrest. Methods 15 Isofluorane anesthetized pigs (30±1Kg), after 6 minutes of untreated ventricular fibrillation, were subsequently randomized to receive either 15 minutes of standard CPR (S-CPR) (8 animals) or 5 minute epochs of S-CPR followed by active compression-decompression (ACD) +inspiratory impedance threshold device (ITD) CPR followed by ACD+ITD+abdominal binding (AB) with 1mg of SNP administered at minutes 2, 7, 12 of CPR (7 animals). Primary endpoints were CBF and ROSC rates. ANOVA and Fisher’s exact test were used for comparisons. Results/Conclusion There was significant improvement in the hemodynamic parameters in the SNP animals. ROSC was achieved in 7/7 animals that received SNP and in 2/8 in the S-CPR (p=0.007). CBF and end tidal CO2 (ETCO2) were significantly higher in the ACD+ITD+AB+SNP (SNPeCPR) animals during CPR. Bolus doses of SNP, when used in conjunction with ACD+ITD+AB CPR, significantly improve CBF and ROSC rates compared to S-CPR.

Sodium nitroprusside enhanced cardiopulmonary resuscitation prevents post-resuscitation left ventricular dysfunction and improves 24-hour survival and neurological function in a porcine model of prolonged untreated ventricular fibrillation

“…However, another study performed by our group demonstrated incremental benefit to each mechanical component of SNPeCPR by examining them independently. 36 The role of SNP in addition to the mechanical CPR platform of SNPeCPR, has also been established and has been shown to improve neurological intact survival. 10 Finally, in this model the coronary arterial bed was patent, and we are not able to extrapolate these results to an ischemic model of cardiac arrest.…”

Sodium Nitroprusside–Enhanced Cardiopulmonary Resuscitation Facilitates Intra-Arrest Therapeutic Hypothermia in a Porcine Model of Prolonged Ventricular Fibrillation*

“…SNPeCPR improved vital organ perfusion pressure, carotid blood flow, and 24h survival with good neurologic outcome in similar studies (10-12, 23). The increase of cerebral blood flow provided by SNPeCPR in combination with improved heat exchange due to the peripheral vasodilation explains the faster cooling rate observed.…”

“…The combination of SNP with a mechanical CPR platform [active compression-decompression (ACD) CPR combined with an inspiratory impedance threshold device (ITD) plus abdominal binding] is referred to as SNPeCPR. SNPeCPR has been shown to optimize hemodynamics during CPR and divert blood flow to the brain and heart with improved 24h survival, neurologic function, left ventricular function, and vital organ blood flow after prolonged cardiac arrest in pigs (10-12). …”

New Application of a Traditional Vasoactive Agent, Sodium Nitroprusside, in Targeted Temperature Management During Cardiac Arrest and Resuscitation*

“…Recently, the combination of SNP with mechanical CPR (SNPeCPR) has been proven to optimize hemodynamics during CPR and improve myocardial and neurologic function and therefore the survival outcome in animal studies (12,13). Based on the publication, in this issue of Critical Care Medicine, Debaty et al (14) investigated the effect of SNPeCPR on heat exchange during surface cooling in a prolonged ventricular fibrillation (VF) porcine model.…”