Post-dural-puncture headache


Post-dural-puncture headache is a complication of puncture of the dura mater. The headache is severe and described as "searing and spreading like hot metal", involving the back and front of the head and spreading to the neck and shoulders, sometimes involving neck stiffness. It is exacerbated by movement and sitting or standing and is relieved to some degree by lying down. Nausea, vomiting, pain in arms and legs, hearing loss, tinnitus, vertigo, dizziness and paraesthesia of the scalp are also common.
PDPH is a common side effect of lumbar puncture and spinal anesthesia. Leakage of cerebrospinal fluid puncture causes reduced fluid levels in the brain and spinal cord. Onset occurs within two days in 66% of cases and three days in 90%. It occurs so rarely immediately after puncture that other possible causes should be investigated when it does.
Using a pencil point rather than a cutting spinal needle decreases the risk. The size of the pencil point needle does not appear to make a difference. PDPH is estimated to occur in between 0.1% and 36% people following dural puncture.

Signs and symptoms

PDPH typically occurs hours to days after puncture and presents with symptoms such as headache and nausea that typically worsen when the patient assumes an upright posture. The headache usually occurs 24–48 hours after puncture but may occur as many as 12 days after. It usually resolves within a few days but has been rarely documented to take much longer.

Pathophysiology

PDPH 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.

Diagnosis

Differential diagnosis

Although in very rare cases the headache may present immediately after a puncture, this is almost always due to another cause such as increased intracranial pressure and requires immediate attention.

Prevention

Using a pencil point rather than a cutting spinal needle decreases the risk. The size of the pencil point needle does not appear to make a difference, while smaller cutting needles have a low risk compared to larger ones. Modern, atraumatic needles such as the Sprotte or Whitacre spinal needle leave a smaller perforation and reduce the risk for PDPH.
Morphine, cosyntropin, and aminophylline appear effective in reducing post dural puncture headaches. Evidence does not support the use of bed rest or intravenous fluids to prevent PDPH.

Treatment

Some people require no other treatment than pain medications and bed rest. A 2015 review found tentative evidence to support the use of caffeine.
Persistent and severe PDPH may require an epidural blood patch. A small amount of the person'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.

Epidemiology

Estimates for the overall incidence of PDPH vary between 0.1% and 36%. It is more common in younger patients, females and those with a low body mass index. The low prevalence in elderly patients may be due to a less stretchable dura mater. It is also more common with the use of larger diameter needles. A 2006 review reported an incidence of:
On the Birmingham gauge, these correspond to the values 27–24G, 22–20G and 19–16G.
PDPH is roughly twice as common in lumbar puncture than spinal anaesthesia, almost certainly due to the atraumatic needles used in spinal anaesthesia.