Abstract P44: Use of Sodium Nitroprusside in Combination With Active Enhancement of Venous Return Improves Cerebral Blood Flow During Prolonged CPR
Introduction: We hypothesized that injection of a large dose of sodium nitroprusside (SN) during CPR, combined with mechanical enhancement of venous return, would result in improved cerebral blood flow by significantly decreasing systemic vascular resistance while maintaining vital organ perfusion pressures.
Methods: Fifteen intubated and propofol-anesthetized pigs had 5 minutes (min) untreated ventricular fibrillation. Eight animals were randomized to control (group A) and 7 animals to SN (group B). Group A had 15 min of standard (STD) CPR with continuous compressions (rate: 100/min, ventilations: 10/min, FiO2: 1.0). Group B had 5 min of STD CPR, followed by 5 min of active compression decompression CPR with an inspiratory impedance threshold device (ACD+ITD) and another 5 minutes of ACD+ITD plus abdominal binding (AB). SN bolus (1 mg) was given intravenously at minutes 2, 7 and 12. Only Group A received intravenous epinephrine to achieve return of spontaneous circulation (ROSC). At 15 min, biphasic DC 200 J shock cardioversion was performed and survivors were kept alive for 30 minutes. Thoracic aortic, right atrial and intracranial pressures were continuously recorded. Internal carotid doppler blood flow (CBF) was continuously measured. Arterial blood gasses were monitored with each intervention. ANOVA, t- test and Chi square were used for statistical analysis.
Results: (shown in table⇓).
Conclusion: The use of a potent arterial vasodilator (SN) combined with mechanically enhanced venous return, improves vital organ perfusion pressures and carotid blood flow, promoting ROSC during prolonged CPR.