Institution: | a Department of Cardiothoracic Surgery, Cardiovascular Research Centre , Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmarkb Institute of Clinical Medicine, Aarhus University, Aarhus, Denmarkc Department of Anaesthesiology and Intensive Care, Cardiovascular Research Centre, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmarkd Thrombosis Research Unit, Department of Cardiology, Aalborg AF Study Group, Cardiovascular Research Centre, Aalborg Hospital, Aarhus University Hospital, Aalborg Denmarke Department of Clinical Biochemistry, Cardiovascular Research Centre, Aalborg Hospital, Aarhus University Hospital, Denmark |
Abstract: | IntroductionTreatment of massive pulmonary embolism leading to cardiac arrest is controversial but restitution of circulation within a shorter time is crucial. Cardiopulmonary support and therapeutic hypothermia is an option for cardiac arrest and could be used to treat massive PE. However, hypothermia may influence the effect of the ongoing intrinsic fibrinolysis.ObjectivesTo establish a porcine model of massive pulmonary embolism, to show that cardiopulmonary support can rescue pigs with massive pulmonary embolism and to examine the effect of hypothermia on fibrinolysis.MethodsPigs ~ 80 kg were anesthetised and prepared for cardiopulmonary support. Repetitive injections of preformed blood thrombi into the right atrium were done until cardiac arrest. Cardiopulmonary support was established and eighteen pigs were randomised into 3 groups: Normothermia (38-39 °C); hypothermia (33-34 °C); or medication with recombinant tissue plasminogen activator. After three hours the pigs were weaned from cardiopulmonary support, and after 15 minutes with spontaneous circulation assassinated and autopsied. Remaining thrombi in the lungs were weighed.ResultsThe development of fatal pulmonary embolism was highly reproducible. All 18 pigs could be weaned from cardiopulmonary support and survived more than 15 minutes. The amount of remaining thromboemboli was substantial in all groups and not significantly different between groups. Normothermic group 20.0 ± 2.2 g, Hypothermic group 17.0 ± 3.7 g, and rt-PA group 14.3 ± 3.2 g.ConclusionsCardiopulmonary support could rescue pigs with massive pulmonary embolism. Hypothermia did not reduce the emboli but may for other reasons be beneficial. The optimal additional treatment is still unknown but treatment modalities can be tested in this model. |