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Updated: Sep 23, 2026

Ultrasonographic Assessment During Cardiopulmonary Resuscitation
Published on: October 24, 2020
Revisiting the cardiac versus thoracic pump mechanism during cardiopulmonary resuscitation
Thorsten Haas1, Wolfgang G Voelckel, Volker Wenzel
1Department of Anesthesiology and Critical Care Medicine, Leopold-Franzens-University, Anichstrasse 35, 6020 Innsbruck, Austria. thorsten.haas@uibk.ac.at
Abstract:
The mechanism of forward blood flow due to external chest compressions during cardiopulmonary resuscitation (CPR) remains controversial, with the main theories being based on either a cardiac, or thoracic pump mechanism. Both potential mechanisms are well investigated by echocardiographic assessment. In the present case, a postoperative complication of cardiac tamponade that was detected by a thoracoabdominal CT-scan, led to cardiac arrest with subsequent successful CPR over 15 min until definitive surgical management was performed. This observation suggests that the thoracic pump mechanism may have been the predominant mechanism of forward blood flow in the present case of a pericardial tamponade.
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