OBJECTIVE ASSESSMENT OF HEPARIN REQUIREMENTS FOR HEMODIALYSIS IN HUMANS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 103  (4) , 643-652
Abstract
The abilities of 4 heparin regimens to inhibit activation of blood coagulation, fibrinolysis and the platelet release reaction in humans during renal dialysis were assessed by visible examination of the extracorporeal circulation and by use of radioimmunoassays to FPA [fibrinogen A.alpha.-chain peptide], .beta.15-42 [fibrinogen .beta..beta.-chain peptide] antigen, .beta..GAMMA.G [.beta.-thromboglobulin] and PF4 [platelet factor 4]. A s.c. injection of 5000 IU of heparin administered 1 h before dialysis in 2 patients was either unable to sustain dialysis because of excess fibrin formation or allowed elevated plasma FPA and .beta..GAMMA.G concentrations during dialysis. Injection of 10,000 IU heparin s.c. in 5 patients could sustain dialysis in only 3 patients for 5 h and allowed progressively increasing concentrations of FPA, .beta..GAMMA.G and PF4, as well as fibrin formation, in the extracorporeal circulation. A lower dose of heparin administered i.v. (2500 IU bolus plus 1000 IU/h) to 6 patients was also unable to prevent elevations in FPA and .beta..GAMMA.G 4 h and 5 h after the initiation of dialysis. I.v. administration of heparin at a dose of 5000 IU bolus plus 1500 IU/h completely suppressed generation of FPA during 5-h dialysis and was free of visible fibrin formation in the extracorporeal circulation in 13 patients. The concentration of the fibrinolytic system marker .beta.15-42 antigen did not change significantly in any of the regimens and the concentration of PF4 altered in response to infused heparin as well as to inadequate heparinization. Complete inhibition of activation of coagulation and suppression of the platelet release reaction evidently occurs when high plasma heparin levels (.gtoreq. 0.5 IU/ml) are maintained during dialysis: lower heparin levels may be compatible with dialysis in some patients, but they allow generation of fibrin and the platelet release reaction, which pose a potential risk to the dialysis procedure and to the patient.