|Classification and external resources|
Post-dural-puncture headache (PDPH) is a complication of puncture of the dura mater (one of the meninges that surround the brain and spinal cord). This occurs in spinal anesthesia and lumbar puncture and may, accidentally, occur in epidural anesthesia.
Presentation and pathophysiology
PDPH typically occurs hours to days after puncture and presents with symptoms such as headache (which is mostly bi-frontal or occipital) and nausea that typically worsen when the patient assumes an upright posture.
It is thought to result from a loss of cerebrospinal fluid into the epidural space. A decreased hydrostatic pressure in the subarachnoid space then leads to traction to the meninges with associated symptoms.
The incidence of PDPH is higher with younger patients, complicated or repeated puncture, and use of large diameter needles, in females, in pregnancy, and with darker skin. Modern, atraumatic needles such as the Sprotte or Whitacre spinal needle leave a smaller perforation and reduce the risk for PDPH.
Some patients require no other treatment than analgesics, and bed rest. A 2007 review of the current evidence by Mayo Clinic researchers found "The wide endorsement for caffeine to prevent and treat PDPH found in textbooks and review articles appears to be unwarranted and insufficiently supported by the available pharmacological and clinical evidence."
Persistent and severe PDPH may require an epidural blood patch. A small amount of the patient's blood is injected into the epidural space near the site of the original puncture; the resulting blood clot then "patches" the meningeal leak. The procedure carries the typical risks of any epidural puncture. However, it is effective, and further intervention is rarely necessary.
The conventional medical wisdom over the last several decades for avoiding PDPH has been to use smaller gauge or modern needles which traumatize the dura less or make a smaller dura puncture, thereby lessening CSF leakage that causes PDPH. While these approaches have been effective at lowering PDPH rates, they have been unsuccessful at completely preventing PDPH. There is evidence that a more effective preventative approach is to make a self-closing puncture in the dura, using a simple beveled needle with a specific angle and bevel orientation.  This approach can also prevent PDPH headaches caused by over-penetration during epidural anesthesia (where dural puncture was never intended), since withdrawal of the needle allows the dural puncture to self-close.
The use of a 3-bevel (Quinke) needles is highly associated with PDPH as the geometry of the needle can create a "flap" that allows CSF leakage when inserted in standard horizontal position (open face of needle cephalad). Inserting the needle vertically (open face directed left or right) splits the dural fibers and reduced the flap size. However older clinicians advocate completely inverting the needle and inserting horizontally but upside down so the open face of the Quinke is directed caudad. This also creates a flap but the geometry is inverted so that the flap is on the inside of the dura and is forced closed by hydrostatic pressure. The incidence of PDPD using a Quinke needle in standard orientation is approximately 3%-7%, Approximately 1.5%-3% when inserted vertically; Approximately 0.1% when inserted inverted.
- Turnbull DK, Shepherd DB (November 2003). "Post-dural puncture headache: pathogenesis, prevention and treatment". Br J Anaesth 91 (5): 718–29. doi:10.1093/bja/aeg231. PMID 14570796.
- Halker RB, Demaerschalk BM, Wellik KE, et al. (September 2007). "Caffeine for the prevention and treatment of postdural puncture headache: debunking the myth". Neurologist 13 (5): 323–7. doi:10.1097/NRL.0b013e318145480f. PMID 17848873.
- Safa-Tisseront V, Thormann F, Malassiné P, et al. (August 2001). "Effectiveness of epidural blood patch in the management of post-dural puncture headache". Anesthesiology 95 (2): 334–9. PMID 11506102.
- Bela I. Hatfalvi, M.D. (July–August 1995). "Postulated Mechanisms for Post Dural Puncture Headache: Clinical Experience and Review Of Laboratory Models". Regional Anesthesia 20 (4): 329–336.