Optimizing Ultrafiltration Heparin Protocols

Anaheim—A study found that heparin protocols involving higher target partial thromboplastin time (PTT) ranges, shorter recheck intervals, and higher PTT hold criteria may be effective in improving the safety and efficacy of ultrafiltration and decreasing hospital costs. The results were presented at the ASHP meeting during a poster presentation titled Adjustment of a Standardized Pharmacy Heparin Dosing Protocol for Use in Acute Heart Failure Patients Receiving Ultrafiltration. In patients with acute decompensated heart failure, ultrafiltration removes excess fluid through convection across a hemofilter. If the hemofilter is coagulated, ultrafiltration may be delayed, which can significantly increase hospital costs. Healthcare professionals are interested in finding an adequate heparin protocol to maintain the hemofilter’s integrity. In this study, the authors wanted to evaluate the maintenance of hemofilter integrity and effective PTT in patients receiving ultrafiltration. At Lutheran Health Network in Fort Wayne, Indiana, clinicians use a standard curve-based pharmacy heparin protocol to monitor and adjust heparin therapy. The authors applied the same protocol to patients receiving ultrafiltration. They began with a 70 unit/kg intravenous (IV) bolus and a 15 unit/kg/hr heparin infusion. Patients >65 years of age received a 50 unit/kg IV bolus and 12 unit/kg/hr initial infusion with a therapeutic PTT range of 55 to 95 seconds and a baseline PTT of 38 seconds. The authors adjusted the treatment every 6 hours until they found consecutive PTTs within the therapeutic range. They considered this procedure as protocol 1. In protocol 2, the authors set an adjusted target PTT between 75 and 95 seconds and rechecked the PTT every 6 hours until the patients were therapeutically stable. Protocol 3 included a target PTT between 80 and 100 seconds. The target PTT was rechecked every 4 hours until patients were therapeutically stable. Patients with PTTs ≤160 seconds did not receive the heparin infusion. The times to therapeutic threshold (TT) varied in the protocols, with protocol 1 having a TT of 12.3 hours, protocol 2 having a TT of 12.7 hours, and protocol 3 having a TT of 8.7 hours. The percentage of PTTs above TT for protocol 1 was 70% for protocols 1 and 2 and 69% for protocol 3. The percentage of PTTs that fell within the protocol’s therapeutic range was 52% in protocol 1, 42% in protocol 2, and 33% in protocol 3. There was a significant difference between protocols 1 and 3 (P<.01). The hemofilter clotting rate was 42% for protocol 1, 30% for protocol 2, and 0% for protocol 3. There was a significant difference between protocols 1 and 3 (P<.0005). The authors noted that none of the patients suffered from significant bleeding. In addition, 1 patient in the first protocol group developed a hematoma and had to discontinue therapy. Costs associated with using hemofilters include losing filters, delaying treatments, and increasing length of hospital stays. According to the authors, the costs can be limited by optimizing ultrafiltration heparin protocols.