A female client with liver cirrhosis suddenly develops epistaxis while on a heparin infusion. Which laboratory value indicates that the heparin infusion needs to be turned off?

• A. Hematocrit of 30%
• B. Partial thromboplastin time of 110 seconds
• C. Platelet count of 80,000/mm3
• D. Prothrombin time of 11 seconds

Answer: (B)

When managing a client on heparin, monitoring the activated partial thromboplastin time (aPTT) is essential to ensure effective anticoagulation without causing excessive bleeding. A normal aPTT is generally about 30 to 40 seconds. When aPTT rises significantly—generally above 80 to 100 seconds—this indicates a high risk of bleeding complications, including epistaxis.

In this scenario, the patient has developed epistaxis while on heparin, and a partial thromboplastin time of 110 seconds suggests a significantly elevated level due to the heparin infusion. This elevated aPTT value indicates that the anticoagulation effects of heparin may be too strong, putting the patient at a greater risk for bleeding. Therefore, it's imperative to turn off the heparin infusion to prevent further complications.