INR 17 and Hematuria: What To Do?

Case 1

A 32-yo AAM is admitted to the hospital with CC: hematuria and back pain x 2 days.

He is on Coumadin 15 mg daily for a PE in the past. He has not had his INR checked for the last 2 months.

What is going on?
He may be overanticoagulated with INR as high as his Coumadin dose (15 mg daily).

Reason for the Back Pain?
The lower back pain may be due to a back sprain but may also secondary to a retroperitoneal hematoma

What is the hematuria cause?
Hematuria is most likely due to Coumadin overdose.

What to do?
Check INR/PTT
CBCD, CMP
CT abdomen

Labs:
INR 11
CT abdomen: no retroperitoneal hematoma


Laboratory results revealed INR of 11

How much vitamin K to give?
Patient refused SQ or IV injections.
Vitamin K 5 mg PO x 2 was given.

How long does it take for vitamin K to bring down INR?
Vitamin K usually acts within 6 hours.
That is why you should check INR q 6 hrs until a desired level is reached, after you give vitamin K IV.

What happened?
The repeated INR was 1.6.
Hematuria stopped, and back pain resolved.
Patient left AMA, realizing the risks involved if he does not follow up on his condition with a physician.

What did we learn from the case?
Vitamin K works fast. You have to use it with caution in patients who need anticoagulation because it can induce Coumadin resistance. This patient needed vitamin K because of hematuria.

Case 2

A 65-yo AAM with a complicated PMH of DM 2, PVD S/P L AKA, CAD, AFib, HTN, CRI was taking Coumadin 15 mg PO daily for AFib.

He had his INR checked today and the lab technician called the PCP office informing him that the patient's INR was 7. The attending asked the patient to come to the hospital as a direct admission.

When we checked our computer system the INR was actually >17 (so high that it was outside the limits of the test) rather than 7 !!!


Laboratory results showed INR of 17

What to do?
Repeat the test?
Repeated INR was 16.30 with PTT>100

That was confusing. Is it DIC?
No. Platelets were normal.

How would you treat such a patient?
Give vitamin K 10 mg PO x 1.

This is faster than the FFP 4 U x 1, which he also received.

Then, check INR q 6 hrs. Type and screen 2 U PRBC, just in case there is excessive bleeding.

What happened?
Repeated INR 8 hours later was 2.99.

This an example of another therapeutic success for Vit.K. Hematuria resolved.

What did we learn from this case?
Always check the labs yourself. Do not rely on a telephone (mis) communication.

Vitamin K is effective and it works well when taken PO. There is rarely need for IV administration. Avoid giving too much vitamin K because it will induce Coumadin resistance.

According to a recent meta-analysis, oral and intravenous vitamin K are equivalent for treatment of excessive anticoagulation. Subcutaneous vitamin K is inferior to oral and intravenous vitamin K and is similar to placebo at 24 hours after administration.

References:
Warfarin: The Asymptomatic Patient with an Elevated INR. Roberts, James. Emergency Medicine News:Volume 29(2)February 2007, p 13-16.
Warfarin Therapy: Evolving Strategies in Anticoagulation. AFP 1999.
Treatment of Excessive Anticoagulation With Phytonadione (Vitamin K). A Meta-analysis. Arch Intern Med. 2006;166:391-397. Link via Notes from Dr. RW

Created: 02/2005
Updated: 07/04/2007