A client’s prothrombin time is 18 seconds with a control of 11 seconds. How should the nurse interpret these findings?

To interpret a prothrombin time (PT) of 18 seconds with a control of 11 seconds, it's essential to understand the relationship between a client's PT and the control value. The prothrombin time is a blood test that measures how long it takes for blood to clot and is often used to monitor anticoagulation therapy, especially in patients receiving medications like warfarin.

In this case, the client's PT is significantly longer than the control value. To assess if this result is above, at, or below the therapeutic range, the PT must be evaluated in relation to the expected therapeutic range for patients on anticoagulants. Typically, the therapeutic range for patients on warfarin is about 1.5 to 2.5 times the control value.

Calculating the ratio:

• PT/Control = 18 seconds / 11 seconds ≈ 1.64.

This ratio falls within the therapeutic range for patients on anticoagulation therapy. Thus, a PT of 18 seconds indicates that the client's coagulation status is adequately controlled with therapy, aligning with the standard anticipated therapeutic ranges.

This understanding clarifies that the prothrombin time is effectively managed in the context of anticoagulation therapy, confirming