PDPH

Post-dural puncture headache (PDPH) is a form of headache that occurs after puncture of the dura mater, most often following lumbar puncture or neuraxial anesthesia. It is characterized by a relief when lying flat and a worsening of pain when upright. The risk varies with the procedure, needle type and size, and patient factors; use of smaller-diameter, atraumatic (pencil-point) needles reduces the likelihood of PDPH.

Pathophysiology involves leakage of cerebrospinal fluid through the puncture site, leading to lowered intracranial pressure and brain sag with traction on pain-sensitive structures. This is commonly accompanied by dilation of intracranial vessels, which contributes to the headache and associated symptoms. Onset is typically within hours to a few days after the dural puncture and can persist for several days to weeks in some cases.

Clinical presentation usually includes a bilateral, throbbing headache that is most prominent when standing or sitting and relieved by recumbency. Patients may also experience neck stiffness, photophobia, nausea, and, less often, tinnitus or transient cranial nerve symptoms. Red flags prompting further evaluation include fever, meningismus, focal neurological signs, or severe changes in mental status.

Diagnosis is primarily clinical, based on temporal relation to a dural puncture and the orthostatic nature of the pain. Imaging or laboratory studies are not routinely required unless the presentation is atypical or complications are suspected.

Management begins with conservative measures such as adequate hydration, simple analgesics, and caffeine-containing beverages. Epidural blood patching is the most effective specific treatment for persistent PDPH, offering symptom relief in the majority of patients. Preventive strategies focus on procedural techniques, notably using atraumatic needles and meticulous technique.

Prognosis is generally favorable; most PDPHs resolve within days to weeks, with rapid improvement after an epidural blood patch when indicated. Recurrence is uncommon but possible.