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Articles 1 - 7 of 7
Full-Text Articles in Biomedical Engineering and Bioengineering
Biophysics Of Cardiopulmonary Resuscitation With Periodic Z-Axis Acceleration Of Abdominal Compression At Aortic Resonant Frequencies, Charles F. Babbs
Biophysics Of Cardiopulmonary Resuscitation With Periodic Z-Axis Acceleration Of Abdominal Compression At Aortic Resonant Frequencies, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
Periodic z-axis acceleration (pGz)-CPR involves oscillating motion of a whole patient in the head-to-foot dimension on a mechanized table. The method is able to sustain blood flow and long-term survival during and after prolonged cardiac arrest in anesthetized pigs. However, the exact mechanism by which circulation of blood is created has remained unknown. Objectives: To explain the hemodynamic mechanism of pGz-CPR and to suggest theoretically useful improvements. Method: Computer modeling using a hybrid analytical-numerical approach, based upon Newton’s second law of motion for fluid columns in the aorta and vena cavae, Ohm’s law for resistive flow through vascular beds, and …
Interposed Abdominal Compression Cpr: A Comprehensive Evidence Based Review, Charles F. Babbs
Interposed Abdominal Compression Cpr: A Comprehensive Evidence Based Review, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
Interposed abdominal compression (IAC)-CPR includes all steps of standard external CPR with the addition of manual mid-abdominal compressions in counterpoint to the rhythm of chest compressions. IAC-CPR can increase blood flow during CPR about two fold compared to standard CPR without IAC, as shown by 6 of 6 studies in computer models and 19 of 20 studies in various animal models. The addition of IAC has clinical benefit in humans, as indicated in 10 of 12 small to medium sized clinical studies. The technique increases the frequency of immediate return of spontaneous circulation for in-hospital resuscitations from roughly 25% to …
The Evolution Of Abdominal Compression In Cardiopulmonary Resuscitation, Charles F. Babbs
The Evolution Of Abdominal Compression In Cardiopulmonary Resuscitation, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
Objective: To review the history of external abdominal compression as an adjunct to cardiopulmonary resuscitation (CPR), tracking the development of five major themes over the course of the 20th century: 1) augmentation of peripheral resistance by physical means, 2) risk of hepatic injury with abdominal compression, 3) counterpulsation vs. sustained compression, 4) the abdominal pump mechanism, and 5) contact compression techniques. Methods: Literature retrieved from successive MEDLINE English-language searches was reviewed with a special emphasis on work and concepts highlighted by participants at the First Purdue Conference on Interposed Abdominal Compression-CPR, September 1992. Results: External abdominal compression of one form …
Interposed Abdominal Compression Cardiopulmonary Resuscitation: Are We Missing The Mark In Clinical Trials?, Charles F. Babbs
Interposed Abdominal Compression Cardiopulmonary Resuscitation: Are We Missing The Mark In Clinical Trials?, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
Straightforward considerations of abdominal anatomy in human beings set tight constraints on the theoretically optimal technique for abdominal compressions during interposed abdominal compression (IAC)-CPR. The location and extent of the abdominal aorta lead naturally to the recommendation that IAC be applied at a level corresponding to the lower two thirds of the sterno-umbilical line. The force vector required to achieve contact compression of the abdominal aorta is inclined in the transverse plane at an angle of 11 degrees from the vertical toward the left. Such slightly angled compression subjects the abdominal aorta to maximally flattening; while the inferior vena cava …
Abdominal Binding And Counterpulsation In Cardiopulmonary Resuscitation, Charles F. Babbs, William E. Blevins
Abdominal Binding And Counterpulsation In Cardiopulmonary Resuscitation, Charles F. Babbs, William E. Blevins
Weldon School of Biomedical Engineering Faculty Publications
The history and potential of abdominal pressure as an adjunct to standard cardiopulmonary resuscitation (CPR) is reviewed. Abdominal pressure during CPR may be either static or phasic. Static abdominal pressure redirects limited blood flow generated by chest compressions toward the heart and brain, and away from the abdominal organs and lower extremities, thus boosting coronary perfusion pressure. Phasic abdominal pressure applied whenever chest pressure is released, in counterpoint to the rhythm of chest compression—so called interposed abdominal compression (IAC)-CPR—generates blood flow by an independent abdominal pump mechanism that augments the systemic perfusion created by chest compressions. New imaging data are …
Regional Blood Flow During Cardiopulmonary Resuscitation With Abdominal Counterpulsation In Dogs, William D. Voorhees Iii, Sandra H. Ralston, Charles F. Babbs
Regional Blood Flow During Cardiopulmonary Resuscitation With Abdominal Counterpulsation In Dogs, William D. Voorhees Iii, Sandra H. Ralston, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
The addition of abdominal counterpulsation to standard cardiopulmonary resuscitation (IAC-CPR) during ventricular fibrillation has been shown to improve cardiac output, oxygen uptake, and central arterial blood pressure in dogs. The present study was performed to determine the effect of IAC-CPR on regional blood flow. Regional blood flow was measured with radioactively labeled microspheres during sinus rhythm and during alternate periods of IAC-CPR and standard CPR (STD-CPR) in nine dogs anesthetized with pentobarbital. Blood pressures and oxygen uptake were measured continuously. As in previous studies, diastolic arterial pressure was higher (30.8%) during IAC-CPR than during STD-CPR, as were cardiac output (24.5%) …
Improved Oxygen Delivery During Cardiopulmonary Resuscitation With Interposed Abdominal Compressions, William D. Voorhees, Mark J. Niebauer, Charles F. Babbs
Improved Oxygen Delivery During Cardiopulmonary Resuscitation With Interposed Abdominal Compressions, William D. Voorhees, Mark J. Niebauer, Charles F. Babbs
Weldon School of Biomedical Engineering Faculty Publications
The ability of a new modification of cardiopulmonary resuscitation (CPR) to deliver oxygen to tissues was evaluated. The method utilizes standard CPR techniques with the addition of manual abdominal compressions (100 mm Hg) interposed between chest compressions, and is termed interposed abdominal compression-CPR (IAC-CPR). Oxygen delivery was measured by a spirometer in a closed circuit designed to permit positive-pressure ventilation synchronized with mechanical chest compression. Ventricular fibrillation was induced electrically in 10 anesthetized dogs. In each dog, trials of IAC-CPR and standard CPR were alternated every five minutes during a 30-minute period. Arterial and central venous blood pressures, oxygen consumption, …