Effect of lidocaine pretreatment on acute hemorrhagic shock in the anesthetized rat.

The hemodynamic and ultrastructural effects of lidocaine HCl pretreatment were assessed on anesthetized rats subjected to acute hemorrhagic shock. After 40 minutes of acute hemorrhagic shock (mean arterial pressure = 40 mmHg), significantly less fluid infusion was needed to return mean arterial pressure to 120 mmHg in lidocaine HCl treated animals as compared to the hemorrhagic shock-untreated group (p less than 0.05). Heart rate was significantly lower in lidocaine treated animals in the immediate post-shock period (p less than 0.05). Twenty minutes after resuscitation from shock, arterial pressures, and heart rate were not significantly different from baseline values in the lidocaine HCl group. However, in the hemorrhagic shock-untreated group all arterial pressures were still significantly lower than their baseline values (p less than 0.05). Ultrastructural myocardial ischemic changes appeared to be less severe in the lidocaine HCl treated animals. Lidocaine HCl pretreatment improved the response to hemorrhagic shock and reinfusion in this model of hemorrhagic shock.