Headache in the parturient: Pathophysiology and management of post-dural puncture headache

Abstract

Headache in the postpartum period is common and multifactorial in origin. Apart from primary causes such as tension headaches and migraine, secondary headaches such as post-dural puncture headache (PDPH) are increasingly common because of increasing use of regional anaesthesia and analgesia during childbirth. Preventive measures for PDPH include the use of smaller gauge pencil-point needles for spinal blocks; epidural needles of 18 G or less; using saline rather than air for epidural space identification and the use of ultrasound guidance, especially for difficult cases such as morbid obesity and spinal deformities. In case of accidental dural puncture (ADP), the choice is between inserting the catheter in an adjacent space or intrathecal catheterization. Current evidence seems to be in favour of inserting the epidural catheter into the subarachnoid space and using the intrathecal catheter for analgesia/anaesthesia after prominently labelling it as intrathecal, to prevent misuse. It should be removed after at least 24 hours and a 10 ml bolus of saline injected before removal of catheter may be helpful. Either way, having written protocols for the management of accidental dural puncture helps to reduce the incidence of PDPH. PDPH can be disabling in severity and can mar the whole experience of childbirth. In addition, severe untreated PDPH can cause complications such as nerve palsies, subdural hematoma and cerebral venous thrombosis. Conservative methods of treatment should be tried first such as adequate hydration, paracetamol, caffeine, sumatriptan or ACTH/hydrocortisone. Epidural blood patching is the most effective treatment for PDPH. It is more effective if done 24-48 hours after dural puncture. It is an invasive procedure with its own complications as well as a failure rate of up to 30%, so that a second or even third patch may be necessary. Both these facts should be intimated to the patient beforehand. Meticulous follow-up and evaluation of these patients is an important responsibility of the obstetric and anaesthetic team. Persistent headache, loss of the postural nature of the headache, altered sensorium, onset of focal neurological deficits and seizures are all features necessitating further investigation including neuroradiological imaging.