Proceedings

Effects of the Memo-Concentrator on Blood

¹ Division of Cardiovascular Surgery, Department of Surgery, North Shore University Hospital, Manhasset, NY
² Department of Surgery, Cornell University Medical College, New York, NY

^* Direct communications to: Yehuda Tamari, Division of Cardiovascular Surgery, North Shore University Hospital, Manhasset, NY 11030.

Abstract

A high flux, non-traumatic ultrafilter (UF) can be useful for controlling the volume in the cardiopulmonary bypass circuit. Recently three such devices have been made available. It is the purpose of this work to describe the direct effects of ultrafiltration with one of these devices, the HemoConcentrator, on blood. The effects were determined by calculating the net changes in blood components due to hemoconcentration of pump blood at the end of bypass. The net changes were calculated from measurements taken before and after the concentration process. Samples taken pre and post-transfusion of the concentrated blood to the patient were also compared. The blood volume left in the circuit, 2050 ± 136 cc was concentrated by circulation through the UF and a total of 1083 ± 74 cc of plasma water extracted at a rate of 87 ± 3cc/min. The % net change for glucose, chloride, CO₂ , potassium, sodium, BUN, creatinine, and phosphorous approximated the net loss of the plasma water. There were no losses in hemoglobin, albumin, and fibrinogen and only 2.5% losses in white blood cells^** and 15.3% losses in platelets.^** There were no changes in the total amount of free plasma hemoglobin or lactate dehydrogenase.

There was a decrease towards normal in prothrombin time from 48 to 34 sec^** and thrombin time from 7.4 to 2.8 sec.^** Following transfusion of the ultrafiltered blood there were increases in albumin from 3.5 to 4.2 gr/dl,^** WBC from 11.4 to 12.9 × 10³/ul,^** RBC from 2.6 to 3.3 × 10⁶/ul,^** platelets from 150 to 182 × 103 /ul,^** and fibrinogen from 161 to 216 mg/d^*. The RBC indices were not altered by the UF or transfusion. Conclusion: The Hemo-Concentrator is an efficient atraumatic UF device.