NCLEX-RNPharmacological and Parenteral TherapiesMedium
A client receiving a continuous heparin infusion for a deep vein thrombosis has an activated partial thromboplastin time (aPTT) result of 100 seconds; the control range is 25-35 seconds and the therapeutic goal is 1.5-2.5 times control. What should the nurse do first?
- AAdminister a scheduled dose of warfarin
- BDocument the finding and reassess in 6 hours
- CIncrease the heparin infusion rate per protocol
- DStop the heparin infusion and notify the provider
Show answer & explanationAnswer & explanation
Correct answer: D. Stop the heparin infusion and notify the provider
The therapeutic range is 1.5-2.5 x 25-35 sec = 37.5-87.5 seconds. An aPTT of 100 seconds exceeds this range, indicating supratherapeutic anticoagulation and high bleeding risk, so the infusion should be stopped and the provider notified immediately.
Why the other options are wrong
- A. Warfarin is not given to correct a supratherapeutic heparin level and takes days to act.
- B. Waiting 6 hours delays needed intervention for significant bleeding risk.
- C. Increasing the rate would worsen an already excessive anticoagulant effect.
Heparin Therapeutic aPTT Range
The therapeutic aPTT for IV heparin is 1.5-2.5 times the control value; results above this range increase bleeding risk.
- Normal aPTT control ~25-35 seconds
- Antidote for heparin overdose is protamine sulfate
- aPTT is monitored every 6 hours until stable
Memory trick: '1.5 to 2.5 keeps you alive' — the safe multiplier zone