Final answer:
The correct action for a nurse caring for a postpartum client receiving heparin via IV for thrombophlebitis is to monitor for signs of heparin toxicity to ensure the levels remain within a therapeutic range without becoming toxic.
Step-by-step explanation:
A nurse caring for a postpartum client who is receiving heparin via continuous IV infusion for thrombophlebitis should monitor for signs of heparin toxicity. Heparin is an anticoagulant used to prevent and treat thrombosis, and while it is effective in preventing blood clots, it can lead to bleeding complications if not carefully managed. Regular monitoring of the client's partial thromboplastin time (PTT) is critical to ensure that the heparin levels remain therapeutic and do not become toxic. Option (c) is the correct action in this case.
As for the other options, encouraging the client to ambulate frequently may not be advisable due to the risk of dislodging the clot. Similarly, administering oral anticoagulants concurrently with heparin can increase the risk of bleeding and is typically not done until transitioning from IV heparin to oral therapy. Applying warm compresses to the affected calf may help to reduce discomfort, but would not be a primary action over monitoring for heparin toxicity.