Postdural puncture headache

Postdural puncture headache (PDPH) may follow either deliberate or unintentional (accidental) penetration of the interdigitating meninges, the dura and arachnoid mater. It is one of the most common and clinically important complications of regional anaesthesia and analgesia in the obstetric population. The headache develops as a consequence of cerebrospinal fluid loss, low intracranial pressure and cerebrovascular changes in the upright position and can prove debilitating. The diagnosis is clinical, making thorough assessment and regular review all the more important, to revise treatment plans, exclude rare serious pathology such as subdural haematoma, and avoid misdiagnosis. This chapter reviews the pathophysiology, incidence, risk factors (needle, technical and patient related), features, natural history, diagnosis, and management of PDPH. High level evidence supports prevention by using small gauge, non-cutting spinal needles, but other preventative strategies against either unintentional dural puncture or PDPH are poorly supported. The absent or poor efficacy of measures such as bed rest, hydration, cerebral vasoconstrictor therapy, epidural or intrathecal saline injection, intrathecal catheter placement or prophylactic epidural blood patch, is noted. Validation of better evidence supporting epidural morphine or intravenous cosyntropin is required. Symptomatic treatment of PDPH is also unreliable. Very limited evidence that requires substantiation supports a modest benefit from caffeine, gabapentinoids or intravenous hydrocortisone. The intervention of epidural blood patch is highly likely to relieve post-spinal PDPH, but only completely resolves epidural needle-induced PDPH in 30–50% of cases. Much detail about EBP remains undetermined, but delayed intervention and injection of approximately 20 mL of autologous blood appear appropriate.