Injections and Blood Thinners

blood thinners

53793176 – render illustration of blood thinner title on pill bottle, isolated on white.

A number of patients, for a variety of reasons, are on medications that are considered blood thinners. Many patients have heart conditions that require them to be on a medication to reduce the risk of blood clots. Stopping these medications can cause multiple problems from clotting of blood vessels to pulmonary embolisms and strokes. Being on blood thinners can cause bleeding problems with or without medical procedures. The big question is whether a specific interventional procedure has more risk for a bleeding complication or whether it is safer to stop the blood thinner for the time being.

Up until recently, the decision to halt blood thinners was based strictly on the risk of bleeds in the surgical acute care settings. Many times injection procedures are done without imaging guidance and have definite risks based on the location of needle placement. Procedures for pain management are usually done with fluoroscope guidance and often are done to structures that have low risks for complications from bleeding. Until recently, risks were determined based on the rate of complications seen in the surgical procedures, and then the risks were estimated for the interventional procedures.

New Information

Recently, several researchers have actually studied the risk of many interventional procedures on blood thinners and also studied the risk of complications from stopping blood thinners. For most experienced interventional pain doctors, they can site cases from their own experience of complications from stopping blood thinners and bleeding problems. Stopping blood thinners does cause problems with strokes and with blood clots forming in harmful places. Fortunately after over 50,000 injections, only a couple of times has a problem occurred in my practice.

The latest research has been done in Pennsylvania. One hospital system in a part of the state has enrolled virtually every person in the area, thus allowing one to study the characteristics of various problems. The first thing the researchers did was find all the people on blood thinners. Then they looked at the incidence of complications from stopping blood thinners for any medical procedure, and the number is about 0.75 people per 1,000 for a problem like stroke or blood clot of some type.

Then they looked at the risk for bleeding with typical injections that are thought to be low risk for bleeding, like joint injections, transforaminal epidural injections and medial branch blocks. The findings were that only minor bleeds occurred and the overall risk of bleeding was 1/4,000 people. That means it usually is more dangerous to stop blood thinners for most interventional procedures for the patient than it is to continue them. For a patient on blood thinners, it means they should be concerned whether the procedure they are undergoing needs to have their medication stopped.

In my practice, if I know a patient is on blood thinners and the procedure is low risk, I will not stop blood thinners. Not many physicians are comfortable with this as of yet since the research is not widely distributed. If as a patient, you are concerned about stopping a blood thinner, it is wise to ask whether it is necessary to stop the blood thinner and whether the procedure can be done in such a way that bleeding is not a significant risk. Sometimes a different approach to an injection will decrease the risk of bleeding. Lastly, a physician who is very experienced with injections will usually be able to place a needle for injection with less trauma due to their ability to overcome obstacles of the anatomy in the area. Experience does count and being specially trained in the area of interventional pain medicine helps with being up-to-date with the changing standards of care for challenging patients.