Bill(*) had a really bad headache and died before he could call 911. He died of a complication of warfarin which he was taking to prevent blood clots. Instead, the best intentions to prevent a stroke lead to uncontrolled bleeding in the brain, high pressure inside the skull and death.
Warfarin and other anticoagulants are necessary medications but also dangerous medications. People take the medications because the risk of blood clots, for them, is higher than the risk of anticoagulation. The last thing a patient wants is for drug management errors to tip balance so the risk of the medication is too high.
So, what are the expectations of people who take warfarin? What do they expect of their providers? What do the providers expect of them?
- Patients expect providers to follow drug guidelines to the letter
- Providers expect patients to follow instructions and learn about warfarin
- Patients want to be in the loop — meaning the risks are high so they want to be in a position to make sure the necessary communication happens and dose adjustments make sense.
- Providers need to be able to contact patients and expect positive feedback — “message received, will change dose to ___ as directed”
- Patients expect a consistent process no matter the day of the week or which provider is on call.
- Above all, patients expect adequate prevention and minimum risk.
Here are several marks of quality warfarin management:
- The same day of drawing lab (INR) the patient is informed 1) the result 2) the change in dose and 3) the date of the next lab. Finger-stick methods with quick results allow some offices to provide instructions before the patient leaves the office.
- The patient is asked to keep a record of results and instructions. And, to “read back” the instructions. Thus the provider knows the patient got the right message.
- The patients have the phone number to call for any evidence of abnormal bruising or bleeding. They should expect to get lab tested or go to the emergency room.
- There is no impediment to getting the warfarin prescription refilled when needed.
- Providers use computer applications or paper tables to select the correct warfarin dose. Only if there are unusual problems do they deviate from established guidelines.
- If the INR is out of range the dose is changed and the INR is rechecked within a week — even if the patient was on a monthly lab routine.
- The day the INR is checked patients do not take the usual warfarin dose until the results are available.
- Providers never say “just keep taking the same dose unless we call you”. That is a recipe for disaster if a lab test is lost or sent to the wrong provider.
- The lab the patient uses is open 7 days a week.
- Providers instruct patients to follow a consistent diet so the amount of vitamin K in the diet is fairly constant. A sudden drop in vitamin K intake causes the INR to rise and bleeding risk to increase.
Back to the case of Bill. He forgot to get his INR checked on Friday and nobody called him to check why. He knew the lab was not open on the weekend. The nosebleed was unusual but not too bothersome — besides, his doctor was not on call and he did not know who to call. He took a slight fall and bumped his head – he didn’t think small head injuries were risky. He had a good memory but sometimes forgot how many warfarin pills to take on Saturday so he took 2. Wrong, wrong and wrong. The outcome might be better if the medical process was better and if patient education was better.
(*) Bill’s case is not real but such deaths have been reported. It is true warfarin is related to rat poison.