A blood patch procedure involves injecting a small amount of a patient’s own blood near the spinal cord to seal a cerebrospinal fluid (CSF) leak. This technique creates a natural seal, allowing the body to repair the underlying issue.
Purpose of the Procedure
The primary reason for a blood patch procedure is to treat a cerebrospinal fluid (CSF) leak, particularly those occurring after spinal medical interventions. These leaks often cause a post-dural puncture headache (PDPH), characterized by a headache that worsens when sitting or standing and improves when lying flat. This positional headache occurs because CSF leakage reduces fluid pressure around the brain and spinal cord, leading to a downward pull of the brain.
CSF leaks can result from various procedures, including lumbar punctures, epidural injections, or spinal surgeries. During these, a small tear can inadvertently form in the dura mater, the tough outer membrane that encases the brain and spinal cord and contains the CSF. When CSF leaks faster than the body can produce it, the protective cushioning around the brain is diminished, causing the characteristic headache and other symptoms like neck pain, nausea, and changes in hearing or vision. The blood patch procedure aims to resolve this by providing a physical barrier that allows the dura to heal, thereby restoring normal CSF pressure and alleviating symptoms.
The Procedure Explained
The procedure begins with the patient positioned to allow access to the spinal area. The healthcare provider then cleans the skin at the injection site, usually in the lower back, near where the original dural puncture occurred. A local anesthetic is administered to numb the area.
Following numbing, a needle is inserted into the epidural space, which is the area just outside the dura mater. This step is similar to how an epidural injection is performed. Concurrently, a small amount of the patient’s own blood, typically around 20 milliliters, is drawn from a vein, often in the arm. This blood is considered “autologous” because it comes directly from the patient, reducing the risk of adverse reactions.
The drawn blood is then injected into the epidural space. The injected blood spreads and, upon contact with the leaking CSF, begins to clot. This clot acts as a natural seal, physically plugging the hole or tear in the dura mater. The clot helps stop CSF leakage, allowing pressure around the brain and spinal cord to normalize, which alleviates symptoms. The entire injection process usually takes only a few minutes.
After the Procedure
Following a blood patch procedure, patients are typically advised to lie flat for a period, often for one to two hours, to help the blood clot effectively and maximize the procedure’s success. Most individuals report immediate or significant improvement in their headache symptoms. However, it is common to experience some mild discomfort or soreness at the injection site in the back for a few days after the procedure.
Patients are generally encouraged to avoid strenuous activities, heavy lifting, bending, twisting, or straining for a period, often ranging from 24 hours to several weeks, to prevent dislodging the newly formed clot. Staying well-hydrated is also often recommended. While many experience rapid relief, some may have a temporary increase in their previous symptoms or develop new, mild headaches or back pain, which usually resolve within a few days. If symptoms do not improve, worsen, or if new severe symptoms such as fever, increased pain, or neurological changes occur, it is important to contact a healthcare provider immediately for further evaluation.