Improved haemodynamics with increased compression - decompression rates during ACD-CPR in pigs

The haemodynamic effects of variations in the compression-decompression fre quency, 60, 90 and 120 min(-1) during ACD-CPR, were tested in a randomized cross-over design during ventricular fibrillation (VF) in 12 anaesthetized pigs (17-22 kg) using an automatic hydraulic chest compression-decompressio n device. There were significant increases with increasing frequency for me an (+/- S.D.) carotid blood flow (17 +/- 5, 25 +/- 9 and 36 +/- 12 mi min(- 1), transit time flow probe), cerebral blood flow (17 +/- 7 30 +/- 17 and 4 0 +/- 13 mi min(-1) 100 g(-1), radionuclide microspheres) and mean aortic p ressure (34 +/- 8, 37 +/- 10 and 43 +/- 7 mmHg), respectively. Myocardial b lood flow (radionuclide microspheres) and diastolic coronary perfusion pres sure, CPP, increased significantly from 60 to 90 min(-1) with no further si gnificant increase to 120 min(-1) (28 +/- 13, 46 +/- 23 and 49 +/- 19 mi mi n(-1) 100 g(-1) and 25 +/- 8, 31 +/- 11 and 32 +/- 9 mmHg, respectively). R enal and hepatic blood flow also increased with increasing rate. No signifi cant differences in the expired CO, levels were observed. In conclusion inc reasing the compression-decompression frequency from 60 to 90 and 120 min(- 1) improved the haemodynamics during ACD-CPR in a pig model with VF. (C) 19 98 Elsevier Science Ireland Ltd. All rights reserved.