355 A Trial of Terlipressin Compared to Small Volume Resuscitation in a Swine (Sus scrofa) Model of Uncontrolled Hemorrhage and Severe Hemorrhagic Shock

Abstract

anteroposterior chest diameter. In the decompression phase, the chest was pulled upwards with a force of approximately 20 pounds using a suction cup device.Neutron-activated microspheres were injected before VF and then at 5 and 15 minutes after CPR initiation. Arterial blood gasses (ABG) and reference blood samples were drawn to determine washout curves. At the end of the experiment, animals were sacrificed and tissue samples from multiple areas of the brain, heart, and other organs were sent for analysis. Continuous data recordings included the ECG, aortic pressure, right atrial pressure, intracranial pressure (ICP), pulse oximetry, and end-tidal CO2 (ETCO2). Respiratory effort, or "gasping," by the animals during CPR was timestamped. Cerebral perfusion pressure (CerPP) was calculated.A priori calculations, based on prior studies and assuming an alpha of 0.05 and 80% power, suggested the need for 11 animals per group to detect an 80% difference. Studies that did not meet inclusion criteria due to severe technical difficulties, such as catheter dislodgement or inability to adequately compress the chest, were not included in the results. Data are expressed as mean AE standard deviation. An unpaired Student's t-test was used to calculate p-values.Results: Eighteen female pigs weighing 39.5 AE 8.2 kg were randomized to ACD-CPR + ITD in either HUP (n ¼ 8) or SUP (n ¼ 10). Mean cerebral blood flow after 15 minutes of CPR was 0.42 AE 0.05 mL/min/g in the HUP group and 0.21 AE 0.04 in SUP (p < 0.01). Pigs treated with HUP also had lower ICP and higher CerPP when compared to SUP (see Table ). Time to first gasp was 282 AE 51 seconds for HUP group versus 437 AE 185 seconds for SUP (p < 0.05). There was no difference in ETCO2 or ABG values between SUP and HUP.Conclusions: After prolonged ACD-CPR + ITD with 30 elevation of the thorax and head, cerebral blood flow was two-fold higher when compared to standard, supine body position. These findings provide additional, strong support to proceed with a clinical evaluation of HUP ACD-CPR + ITD in humans in cardiac arrest.