### Abstract

An extracorporeal heparin removal device system (HRDS) based on plasma separation and affinity adsorption has been developed to reduce the risks of protamine-related adverse reactions. The heparin clearance profile of the HRDS was characterized by the first-order exponential depletion. A mathematical model was established to predict the time to achieve 85% heparin removal for different body weights at 700 ml/min and 1400 ml/min extracorpurea HRDS blood flow. With an HRDS flow of 700 ml, 85% of total body hepaorin removal cannot be achieved within 30 min for subjects greater than 50 kg. With an HRDS flow of 1400 ml/min, 85% heparin removal can be achieved within 32 min for subjects larger than 90 kg. Such model predictions were validated in an adult swine (n = 10) model of 60-min, hypothermic (28°C) cardiopulmonary bypass (CPB). Animals were given 300 U/ kg intravenous heparin and 5000 U heparin in the circuit prime for initial heparinization, with subsequent heparin given to maintain activated clotting time above 450 sec. Immediately following CPB, plasma heparin concentration as determined by anti-factor Xa assays was 4.40 ± 1.08 U/ml in the 700 ml/min group and 4.78 ± 0.70 U/ml in the 1400 ml/min groups, respectively (p > 0.05). Target HRDS flow was 700 ml/min for animals below 75 kg and 1400 ml/min for animals above 75 kg. The mean body weight in the 1400 ml/min group (81.4 ± 3.7 kg) was significantly higher than that in the 700 ml/min group (67.2 ± 2.2 kg) (p < 0.05), with the actually achieved HRDS flow 658.5 ± 20.8 and 1437.4 ± 30.1 ml/min, respectively. During the HRDS run, plasma heparin concentration followed the predicted first-order exponential depletion (r^{2} = 0.97 for the 700 ml/min group and r^{2} = 0.99 for the 1400 ml/min group). In the 700 ml/min group, the time needed to achieve 85% heparin clearance was over 40 min, whereas in the 1400 ml/min group, this time was reduced to less than 30 min despite greater body weight. At 30 min on HRDS, the 700 ml/min group had 27.4 ± 3.7% heparin left in the plasma, whereas the 1400 ml/min group had only 12.6 ± 2.5% (p < 0.05). The authors conclude heparin clearance by the HRDS can be precisely predicted with the mathematical model of first-order exponential depletion. Increasing the HRDS flow can effectively reduce the time needed to achieve a targeted heparin removal.

Original language | English (US) |
---|---|

Pages (from-to) | 922-926 |

Number of pages | 5 |

Journal | ASAIO Journal |

Volume | 43 |

Issue number | 6 |

State | Published - Nov 1997 |

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### ASJC Scopus subject areas

- Biophysics
- Bioengineering

### Cite this

*ASAIO Journal*,

*43*(6), 922-926.

**Heparin clearance profiles after systemic anticoagulation using a heparin removal device system.** / Tao, Weike; Callahan, Jon D.; Vertrees, Roger A.; Brunston, Robert L.; Deyo, Donald J.; Mcrea, James C.; Zwischenberger, Joseph B.

Research output: Contribution to journal › Article

*ASAIO Journal*, vol. 43, no. 6, pp. 922-926.

}

TY - JOUR

T1 - Heparin clearance profiles after systemic anticoagulation using a heparin removal device system

AU - Tao, Weike

AU - Callahan, Jon D.

AU - Vertrees, Roger A.

AU - Brunston, Robert L.

AU - Deyo, Donald J.

AU - Mcrea, James C.

AU - Zwischenberger, Joseph B.

PY - 1997/11

Y1 - 1997/11

N2 - An extracorporeal heparin removal device system (HRDS) based on plasma separation and affinity adsorption has been developed to reduce the risks of protamine-related adverse reactions. The heparin clearance profile of the HRDS was characterized by the first-order exponential depletion. A mathematical model was established to predict the time to achieve 85% heparin removal for different body weights at 700 ml/min and 1400 ml/min extracorpurea HRDS blood flow. With an HRDS flow of 700 ml, 85% of total body hepaorin removal cannot be achieved within 30 min for subjects greater than 50 kg. With an HRDS flow of 1400 ml/min, 85% heparin removal can be achieved within 32 min for subjects larger than 90 kg. Such model predictions were validated in an adult swine (n = 10) model of 60-min, hypothermic (28°C) cardiopulmonary bypass (CPB). Animals were given 300 U/ kg intravenous heparin and 5000 U heparin in the circuit prime for initial heparinization, with subsequent heparin given to maintain activated clotting time above 450 sec. Immediately following CPB, plasma heparin concentration as determined by anti-factor Xa assays was 4.40 ± 1.08 U/ml in the 700 ml/min group and 4.78 ± 0.70 U/ml in the 1400 ml/min groups, respectively (p > 0.05). Target HRDS flow was 700 ml/min for animals below 75 kg and 1400 ml/min for animals above 75 kg. The mean body weight in the 1400 ml/min group (81.4 ± 3.7 kg) was significantly higher than that in the 700 ml/min group (67.2 ± 2.2 kg) (p < 0.05), with the actually achieved HRDS flow 658.5 ± 20.8 and 1437.4 ± 30.1 ml/min, respectively. During the HRDS run, plasma heparin concentration followed the predicted first-order exponential depletion (r2 = 0.97 for the 700 ml/min group and r2 = 0.99 for the 1400 ml/min group). In the 700 ml/min group, the time needed to achieve 85% heparin clearance was over 40 min, whereas in the 1400 ml/min group, this time was reduced to less than 30 min despite greater body weight. At 30 min on HRDS, the 700 ml/min group had 27.4 ± 3.7% heparin left in the plasma, whereas the 1400 ml/min group had only 12.6 ± 2.5% (p < 0.05). The authors conclude heparin clearance by the HRDS can be precisely predicted with the mathematical model of first-order exponential depletion. Increasing the HRDS flow can effectively reduce the time needed to achieve a targeted heparin removal.

AB - An extracorporeal heparin removal device system (HRDS) based on plasma separation and affinity adsorption has been developed to reduce the risks of protamine-related adverse reactions. The heparin clearance profile of the HRDS was characterized by the first-order exponential depletion. A mathematical model was established to predict the time to achieve 85% heparin removal for different body weights at 700 ml/min and 1400 ml/min extracorpurea HRDS blood flow. With an HRDS flow of 700 ml, 85% of total body hepaorin removal cannot be achieved within 30 min for subjects greater than 50 kg. With an HRDS flow of 1400 ml/min, 85% heparin removal can be achieved within 32 min for subjects larger than 90 kg. Such model predictions were validated in an adult swine (n = 10) model of 60-min, hypothermic (28°C) cardiopulmonary bypass (CPB). Animals were given 300 U/ kg intravenous heparin and 5000 U heparin in the circuit prime for initial heparinization, with subsequent heparin given to maintain activated clotting time above 450 sec. Immediately following CPB, plasma heparin concentration as determined by anti-factor Xa assays was 4.40 ± 1.08 U/ml in the 700 ml/min group and 4.78 ± 0.70 U/ml in the 1400 ml/min groups, respectively (p > 0.05). Target HRDS flow was 700 ml/min for animals below 75 kg and 1400 ml/min for animals above 75 kg. The mean body weight in the 1400 ml/min group (81.4 ± 3.7 kg) was significantly higher than that in the 700 ml/min group (67.2 ± 2.2 kg) (p < 0.05), with the actually achieved HRDS flow 658.5 ± 20.8 and 1437.4 ± 30.1 ml/min, respectively. During the HRDS run, plasma heparin concentration followed the predicted first-order exponential depletion (r2 = 0.97 for the 700 ml/min group and r2 = 0.99 for the 1400 ml/min group). In the 700 ml/min group, the time needed to achieve 85% heparin clearance was over 40 min, whereas in the 1400 ml/min group, this time was reduced to less than 30 min despite greater body weight. At 30 min on HRDS, the 700 ml/min group had 27.4 ± 3.7% heparin left in the plasma, whereas the 1400 ml/min group had only 12.6 ± 2.5% (p < 0.05). The authors conclude heparin clearance by the HRDS can be precisely predicted with the mathematical model of first-order exponential depletion. Increasing the HRDS flow can effectively reduce the time needed to achieve a targeted heparin removal.

UR - http://www.scopus.com/inward/record.url?scp=0031282387&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031282387&partnerID=8YFLogxK

M3 - Article

C2 - 9386844

AN - SCOPUS:0031282387

VL - 43

SP - 922

EP - 926

JO - ASAIO Journal

JF - ASAIO Journal

SN - 1058-2916

IS - 6

ER -