Cardiac Performance during Acute Hemorrhagic Shock in Pentobarbital-anesthetized Hamsters Using Left Ventricular Pressure-volume Measurement

Hemorrhagic shock results from massive blood loss, leading to hypotension, ischemia, heart failure and multiorgan dysfunction. The analysis of cardiac function in vivo is complex and even more challenging during hemorrhagic shock, especially in small animals. Cardiac function measurements require animals to be under anesthesia. Sodium pentobarbital is a common general anesthetic used for cardiovascular physiological studies in experimental animals. This study was designed to evaluate cardiac function during an acute hemorrhagic shock in pentobarbital-anesthetized hamsters. Animals were subjected to a hemorrhage of 40% of blood volume. Cardiac performance was evaluated using a miniaturized pressure-volume conductance catheter. One group of animals was under anesthetic without hemorrhage as a control group and other group was under anesthetic with hemorrhagic shock. We found that dP/dtmax was 77% and 68% of baseline in control and hemorrhagic shock groups, respectively. An estimated left ventricular end-systolic elastance in a hemorrhagic shock group was higher compared with a control group. Cardiac output, stroke volume and stroke work profoundly decreased after hemorrhage. Animals anesthetized with sodium pentobarbital evidently had depressive systolic cardiac function. The depression was more profound in systolic and diastolic cardiac function during hemorrhagic shock.