ACTIVE COMPRESSION-DECOMPRESSION RESUSCITATION - ANALYSIS OF TRANSMITRAL FLOW AND LEFT-VENTRICULAR VOLUME BY TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN HUMANS

Objectives. This study was designed to test the hypothesis that active compression decompression cardiopulmonary resuscitation increases tra nsmitral how and end-decompression left ventricular volume over levels achieved with standard manual cardiopulmonary resuscitation. Backgrou nd. Recently, cardiopulmonary resuscitation incorporating active compr ession and decompression of the chest has been demonstrated to improve hemodynamic status in a canine model and in humans after cardiac arre st. Methods. The active compression decompression device was applied m idsternum in five consecutive patients and results compared sequential ly (in random order) with those of standard manual cardiopulmonary res uscitation. Both techniques were performed at 80 compressions/min with a 1.5- to 2-in. (3.8 to 5.1 cm) compression depth and a 50% duty cycl e. Transesophageal echocardiographic data obtained in each patient inc luded the velocity time integral of transmitral pulsed Doppler recordi ngs and two-dimensional images of the left ventricle in the long-axis view. Planimetric volume measurements of the left ventricle were obtai ned at both end compression and end decompression. Results. No differe nce was observed in end compression volume between the two techniques (p = 0.81). Increased end-decompression volume (active compression dec ompression technique 81.3 +/- 12.5 vs. standard technique 69.4 +/- 10. 8, p < 0.05), stroke volume (active compression-decompression techniqu e 32.6 +/- 6.8 vs. standard technique 17.6 +/- 5.2, p < 0.05) and velo city time integral of transmitral flow (active compression-decompressi on technique 15.8 +/- 4.3 vs. standard technique 7.8 +/- 2.3, p < 0.05 ) were found in the active compression decompression group. The transm itral velocity-time integral was highly correlated with left ventricul ar stroke volume (r = 0.90). Conclusions. Improved transmitral flow, e nd-decompression left ventricular volume and stroke volume are seen wi th active compression-decompression resuscitation, suggesting a biphas ic cardiothoracic cycle of flow. Active decompression of the chest app ears to be a beneficial adjunct to standard cardiopulmonary resuscitat ion.