Post-dural puncture headache

Surgical approach (if applicable)

• Not a surgical operation; key interventional procedure is an epidural blood patch (EBP).
• Typical procedural steps (EBP)
  • Consent: explain benefits, alternatives, risks (back pain, repeat patch, infection, neurological injury, failure).
  • Asepsis; standard monitoring; IV access; resuscitation equipment available.
  • Identify epidural space (often at/near level of puncture; commonly lumbar).
  • Draw autologous venous blood immediately before injection (sterile technique).
  • Inject blood slowly into epidural space until patient reports pressure/back pain (typical 15–20 mL; stop earlier if significant pain/neurological symptoms).
  • Post-procedure: supine rest (commonly 1–2 h), observe, advise to avoid heavy lifting/straining for 24–48 h; safety-net for fever, worsening neuro symptoms, persistent severe headache.

Anaesthetic management (if applicable)

• Context: PDPH occurs after dural puncture (spinal, CSE, accidental dural puncture during epidural, diagnostic LP). Management is usually non-operative; EBP is the main interventional treatment.
• Type of anaesthesia for EBP
  • Usually performed with local anaesthetic infiltration ± minimal sedation; avoid heavy sedation (need patient feedback; airway/aspiration risk postpartum).
  • GA is rarely required (e.g., inability to cooperate) and generally avoided.
• Airway
  • Not applicable for standard EBP (no airway device). If GA required, manage as per standard GA; consider aspiration risk in postpartum patients.
• Duration
  • Procedure typically 15–30 min plus observation period (often 1–2 h).
• Pain
  • Moderate discomfort: local infiltration + pressure/back pain during injection; stop/slow if severe pain or radicular symptoms.

Definition

• Headache attributed to CSF leak through a dural puncture causing intracranial hypotension and traction on pain-sensitive structures; classically postural.

Epidemiology and risk factors

• Incidence varies with needle type/size and patient factors.
• Needle factors
  • Larger gauge increases risk; cutting (Quincke) > pencil-point (Whitacre/Sprotte).
  • Multiple attempts and traumatic puncture increase risk.
  • Epidural Tuohy accidental dural puncture: high PDPH risk (commonly quoted ~50–80%).
• Patient factors
  • Young age, female sex, pregnancy/postpartum, low BMI, history of PDPH/migraine (association varies).
• Technique factors
  • Bevel orientation parallel to dural fibres (for cutting needles) may reduce risk.

Pathophysiology

• Persistent CSF leak → reduced CSF volume/pressure → brain sagging and traction on meninges/cranial nerves; compensatory cerebral vasodilatation may contribute.
• Symptoms worsen upright and improve supine due to further reduction in CSF pressure when standing.

Clinical features

• Timing: typically within 24–72 h of dural puncture (can be immediate or delayed up to ~5 days).
• Headache characteristics
  • Postural: worse sitting/standing, relieved by lying flat (key feature).
  • Often bilateral frontal/occipital; may radiate to neck/shoulders.
• Associated symptoms
  • Neck stiffness, nausea/vomiting, photophobia, tinnitus/hearing changes, diplopia (CN VI palsy), dizziness.
• Functional impact: inability to mobilise/care for baby postpartum; may impair breastfeeding and bonding.

Differential diagnosis (especially postpartum)

• Always consider alternative/serious causes; PDPH is a diagnosis of pattern + context, not exclusion alone.
• Hypertensive disorders
  • Headache with hypertension, visual symptoms, RUQ/epigastric pain, hyperreflexia; check BP, urine protein, bloods.
• Intracranial pathology
  • Subarachnoid haemorrhage (thunderclap), intracerebral haemorrhage, cerebral venous sinus thrombosis (CVST), meningitis/encephalitis, intracranial mass/raised ICP.
• Other common causes
  • Migraine/tension headache, dehydration, caffeine withdrawal, sinusitis.

Assessment and initial work-up

• History: neuraxial procedure details (spinal vs epidural vs ADP), needle type/size, number of attempts, timing and postural nature, associated neuro/visual/auditory symptoms.
• Examination: full neurological exam, cranial nerves, fundoscopy if concern; check BP and temperature.
• When to investigate urgently (imaging/labs)
  • Atypical headache (non-postural, progressive, sudden thunderclap), focal neurology, seizure, reduced GCS, fever/meningism, persistent vomiting, severe hypertension, anticoagulation/bleeding risk.
  • Consider CT/MRI brain ± MR venography if CVST suspected; labs as indicated (FBC, CRP, U&E, LFTs, coagulation).

Prevention

• Use the smallest appropriate spinal needle; prefer pencil-point needles where suitable.
• Minimise attempts; optimise positioning; consider ultrasound for difficult neuraxial anatomy.
• Cutting needle bevel parallel to dural fibres (if used).
• After accidental dural puncture (ADP) with Tuohy: discuss options early; involve senior anaesthetist; clear documentation and follow-up plan.

Management: conservative and pharmacological

• General principles: exclude red flags; treat pain; maintain function; shared decision-making; early review (especially obstetric patients).
• Conservative measures
  • Encourage oral fluids (avoid overhydration as a 'cure'); allow patient to lie flat for symptom relief.
  • Simple analgesia: paracetamol ± NSAID (if no contraindication).
  • Antiemetics if needed.
• Pharmacological options (variable evidence; often temporising)
  • Caffeine (oral/IV): may provide short-term relief via cerebral vasoconstriction; consider side effects (palpitations, anxiety) and breastfeeding considerations; avoid excessive dosing.
  • Opioids: short course only if required; consider sedation and breastfeeding implications.
  • Other agents sometimes used (specialist/obstetric anaesthesia guidance dependent): theophylline, gabapentinoids, triptans—evidence mixed; not first-line in FRCA answers unless asked.

Definitive/interventional management: epidural blood patch (EBP)

• Indications
  • Moderate–severe PDPH affecting mobilisation/care, or persistent symptoms despite conservative therapy.
  • Earlier consideration if severe symptoms or cranial nerve palsy (after excluding other pathology).
• Timing
  • Often offered after 24 h if symptoms significant; success may be lower if performed very early, but clinical severity and patient needs drive decision.
• Contraindications
  • Patient refusal, systemic infection or local infection at insertion site, untreated sepsis, coagulopathy/therapeutic anticoagulation, raised ICP due to mass lesion (concern for herniation).
• Technique essentials
  • Full asepsis; epidural placement; inject 15–20 mL autologous blood slowly; stop if severe back pain, radicular pain, or neurological symptoms.
  • Post-procedure: observe; advise on recurrence; provide written safety-net and contact details.
• Efficacy and next steps
  • High success rate after first patch (often quoted ~70%); second patch can be offered if partial/failed response and diagnosis remains likely.
  • If headache persists or is atypical after EBP: reassess diagnosis; consider imaging and neurology/obstetric medicine input.
• Complications of EBP
  • Common: transient back pain/pressure.
  • Less common/serious: infection (epidural abscess/meningitis), neurological injury, epidural haematoma (esp. anticoagulated), radicular pain, failure/recurrence.

Special situations (obstetrics and anticoagulation)

• Obstetrics
  • High index of suspicion for pre-eclampsia/CVST; check BP and symptoms carefully.
  • Breastfeeding: consider medication transfer (e.g., caffeine, opioids); provide practical advice.
• Anticoagulation/antiplatelets
  • EBP is a neuraxial procedure: follow local policy and national neuraxial anticoagulation guidance (timing relative to LMWH/DOAC/warfarin; check platelets and coagulation where indicated).

Communication, consent, documentation and follow-up

• Explain diagnosis, expected course (many resolve within ~1–2 weeks), and treatment options including EBP and its risks/benefits.
• Document: dural puncture details, counselling, plan, escalation criteria, and review arrangements.
• Provide written advice and contact pathway for worsening symptoms or red flags.