AutoHep™ Feedback Control Drug Delivery System for UF Heparin
The AutoHep System is a feedback control drug delivery system for UF heparin. The system will automate infusion dosing decisions and control UF heparin administration. This medical device system will utilize the Company’s proprietary feedback control algorithms, incorporated into the HepGuide DSS product, and integrate them with automated blood sampling, aPTT measurement and drug administration. The system is expected to dramatically improve the safety and quality of care offered to acute care patients by automating aPTT testing and real-time dosing regimens based on individual patient response to achieve and maintain patients within the therapeutic range. A prototype of the AutoHep System was already developed and successfully demonstrated in a clinical trial.
The Company expects the AutoHep System to provide additional benefits above and beyond the HepGuide DSS product by further reducing the number of manual steps involved in UF heparin administration. While HepGuide DSS will provide vital assistance with UF heparin dosing decisions; medical personnel must still:
- Manually draw blood samples,
- Have those samples analyzed by the central lab,
- Manually enter these results into HepGuide, and
- Manually adjust the UF heparin infusion rate.
The AutoHep System automates all these steps. This will eliminate the need for multiple patient draws, dramatically cut the logistics time required to process samples and acquire aPTT information, and automatically adjust the IV infusion pump rate of UF heparin without the need for manual entry.
System Configuration
The System consists of four elements:
- A Blood Sampler Withdrawal Set which will sample blood directly from an existing venous infusion line
- A disposable Heparin Assay Cassette which will contain multiple aPTT assays to measure the effect of heparin on anticoagulation
- A Medication Control Unit which will host the pharmacodynamic control algorithm that automatically determines the appropriate UF heparin infusion rate, and the optimal time for the next aPTT measurement, along with providing alarms and alerts
- An integrated IV Infusion Pump which will automatically be set to deliver the calculated UF heparin infusion rate, subject to optional nurse or clinician approval
The AutoHep System is being designed to provide cost and time savings to the hospital by freeing up staffing resources that normally would be involved in blood sampling, lab testing, information collection, drug administration and patient monitoring. By optimizing the process and reducing manual steps and opportunities for error, the system should reduce the incidence of medication errors. As a result, patient outcomes would improve while labor resources and costs would be minimized, resulting in higher overall efficiencies.
Key Benefits
The AutoHep System is expected to provide key benefits over standard of practice today and the manual process using HepGuide DSS alone. These include:
- Automating blood sampling using the same infusion line used to administer the drug, thus avoiding multiple patient blood draws for lab samples
- Automating aPTT assays incorporated into the System at beside using the automatic blood sample which will provide instant test results and avoid nurse/phlebotomist sample collection and central lab logistics
- Administering the appropriate infusion rate of UF heparin, automatically or with clinical oversight and approval of pump rate changes
- Utilizing multiple data points to avoid single inaccurate results influencing dosing decisions
- Eliminating time delays in obtaining measurements
- Determining and executing optimum time for the next sample
- Responding to physician-selected high and low limits for aPTT
- Providing safety alarms and alerts if the patient response is out of range
- Transitioning patients to outpatient dosing of warfarin, if required
Initial Clinical Testing of the AutoHep Prototype
The AutoHep prototype system was demonstrated in a successful pilot clinical study. This pilot study demonstrated that the system maintained a high percentage of subjects within a narrow target range. The results were published in Circulation entitled Automated Heparin-Delivery System to Control Activated Partial Thromboplastin Time : Evaluation in Normal Volunteers (PDF). Results are shown in the figure below.
Standard of Nomogram (Left) vs. HepGuide Prototype Software Performance (Right). When compared with the distribution of aPTT measurements in the ESSENCE study shown on the left (Data from Cohen M, et al. N Engle J Med. 1997;337:447–452.), the improvement by the AutoHep System prototype was significant. The prototype software was studied in healthy male volunteers receiving an intravenous infusion of heparin with the rate determined by AutoHep. Of the 344 end-point aPTT measurements, 89% were within a 15-second range of the target (pre-specified primary end point). The total percentage of time within the target range
[+/-]15 seconds was 46 of 48 hours (96%). The automatic blood sampling system successfully obtained 96% of all scheduled samples.