OCR Significantly Reduced Hepatic Microcirculatory Blood Flow After Resuscitation in a Rat Model of Cardiac Arrest

Introduction: Multiple organ dysfunction following successful resuscitation from cardiac arrest is associated with a low survival. Hepatic injuries are common clinical findings following resuscitation. In the present study, we investigated post-resuscitation hepatic microcirculatory changes in a rat model of cardiac arrest and resuscitation. Methods: A total of 15 Sprague-Dawley rats (450-550g) were randomized into two groups: 1) CPR group: 8 mins of untreated ventricular fibrillation (VF) followed by 8 mins of cardiopulmonary resuscitation and defibrillation (n=10); 2) sham control: animals underwent the same surgical procedure only VF and cardiopulmonary resuscitation were not performed (n=5). An upper midline laparotomy was performed to visualize the right lobe of the liver. Ten-second clips of the hepatic microcirculation were captured with the sidestream dark field video microscope at three locations at baseline, 1, 2, 4 and 8 hrs after the return of spontaneous circulation. Mean diameter of sinusoids and sinusoidal blood flow velocity were quantified off-line by using an automated vascular analysis (AVA 3.0) software. Results: Following resuscitation, both sinusoidal diameter (baseline: 10.9±0.7μm, PR 8 hrs: 7.7±0.9μm/s) and sinusoidal blood flow velocity (baseline: 341±58μm/s, PR 8 hrs: 88±19μm/s) decreased significantly when compared with the sham control group (both p Conclusion: Significant reduction in hepatic microcirculatory blood flow was observed following successful resuscitation from cardiac arrest.