OBJECTIVETo evaluate the possibility of radial artery pressure and waveform as a convenient definition of pulsatile flow and the the effect of pulsatile perfusion during cardiopulmonary bypass (CPB) procedures.

METHODSFrom March 2008 to December, Eighty patients underwent open heart surgery were randomly divided into a pulsatile group (P, n=45) and a nonpulsatile group (NP, n=35). Monitored by radial artery pressure and waveform, the pulsatile low was applied from the point of the aortic cross-clamp until its release in P group. A P group of patients whose radial artery pressure and waveform revealed "double peak" or "single peak" (>30 mm Hg, 1 mm Hg=0.133 kPa) were compared with NP group. Parameters examined were lactate, urine volume, high sensitivity C reactive protein, blood urea nitrogen, creatinine, blood uric acid, lactate dehydrogenase, glutamic oxalacetic transaminase, ratio of urine for occult blood test, prothrombin time and tracheal intubation time.

RESULTSThe waveform with "double peak" or "single peak" (>30 mm Hg) presented in 35 (77.78%) in P group. The urine volume during CPB was significantly higher in P group. The lactate (P<0.01) during CPB, high sensitivity C reactive protein (P<0.05), increasing extend of lactic acid dehydrogenase (P<0.05) and the prothrombin time (P<0.01) after CPB were significantly lower in P group. The blood uric acid after CPB was increased in P group and decreased in NP group.

CONCLUSIONSEffective pulsatile flow can be generated by optimization of equipment and adjustment of pulsatile parameter. The radial artery pressure and waveform is a convenient definition of pulsatile flow. The pulsatile flow is predominant monitored by radial artery pressure and waveform.