Description of the condition

Post dural (post lumbar or post spinal) puncture headache (PDPH) is one of the most common complications of diagnostic, therapeutic or inadvertent lumbar punctures (Bezov 2010; Davignon 2002). PDPH is defined as any headache after a lumbar puncture that worsens within 15 minutes of sitting or standing and is relieved within 15 minutes of lying down (IHS 2004). Ninety percent of the PDPHs occur within three days of the procedure and 66% starts in the first 48 hours (Turnbull 2003).

The pathophysiology of PDPH has not been fully described. It is well known that the puncture in the dura allows cerebrospinal fluid (CSF) to leak from the subarachnoid space, resulting in a decrease of CSF volume and pressure (Grande 2005). This CSF volume loss may cause a downward pull on pain‐sensitive structures resulting in a headache (Ahmed 2006; Baumgarten 1987; Davignon 2002; Denny 1987; Harrington 2004). Alternatively, the loss of CSF may cause an increase in blood flow, resulting in arterial and venous vasodilatation and PDPH. A third PDPH explanation involves the role of P substance and the regulation of Neurokinin 1 receptors (NK1R) (Clark 1996).

Occurrence of PDPH varies from 1 to 40%, according to the needle gauge, needle orientation, operator skill level and presence of risk factors such as age group or history of PDPH (Turnbull 2003). This frequency is related to the type of lumbar puncture. During anaesthetic procedures, such as epidural anaesthesia, PDPH is most commonly caused by an unintentional dural puncture (Thew 2008; Turnbull 2003). In contrast to the aforementioned, in diagnostic or therapeutic lumbar punctures, the need for adequate CSF flow requires an intentional lesion that may generate the PDPH phenomenon (Kuczkowski 2006). Estimated frequencies vary from less than 10% following spinal anaesthesia (Hafer 1997; Vallejo 2000), to 36% for diagnostic lumbar punctures (Lavi 2006; Vallejo 2000) and up to 81% in obstetric patients with inadvertent dural puncture during active labour. Reported risk of inadvertent dural puncture placement during epidural anaesthesia in obstetric population, ranges from 0.04% to 6% (Berger 1998; Choi 2003). Therefore, obstetric analgesia is probably the main source of PDPH patients.

The features of PDPH are often variable. PDPH may be accompanied by neck stiffness, tinnitus, hearing loss, photophobia or nausea; other features, such as the location and duration are also unpredictable (Grande 2005). Although PDPH is not a life‐threatening condition, somehow physical activity is often restricted. Likewise patients are usually required to stay in bed the whole day and length of stay in hospital as well as medical attendance increases (Angle 2005).

The variability of symptoms makes PDPH a diagnosis of exclusion. Other alternative diagnoses should be ruled out first e.g. viral meningitis, sinus headache or intracranial haemorrhage (Turnbull 2003). Once PDPH is diagnosed, the initial treatment involves conservative measures such as bed rest and analgesics. If PDPH continues for more than 72 hours, a more specific treatment is indicated (Ahmed 2006). Severe PDPH may respond to some therapeutic drugs and administration of epidural blood patch (Boonmak 2010; Lavi 2006). Two Cochrane reviews are also in process on drug therapy for the prevention and treatment of PDPH (Basurto Ona 2009a; Basurto Ona 2009b).

Description of the intervention

Many publications and reviews of PDPH have focused on treatment once symptoms present. However, the prevention of PDPH is an equally important topic; immobilisation and fluid intake are the two proposed preventive methods that may improve recovery or even prevent PDPH following lumbar puncture.

Sicard first recommended bed rest after a lumbar puncture in 1902. He asserted that patients should rest for 24 hours to prevent PDPH onset (Armon 2005; Coriat 1903). Although the effectiveness of resting is well known for symptom relief, it is debatable whether bed rest prevents the development of symptoms (Davignon 2002). Additionally, there is debate over the appropriate length of bedrest; some authors suggesting that around 4 hours is sufficient, whereas others believe that it should be more than 24 hours (Thoennissen 2001). Aside from the length of rest, it is believed that certain body postures after lumbar puncture, such as a prone position with or without head down tilt may help to prevent PDPH onset.

The effectiveness of fluid intake on PDPH prevention is not well studied. Basic characteristics such as the amount of the fluids and its length have not been established, although some studies suggest that more than five days and three additional litres of fluid to the patient’s current fluid intake is appropriate (Ahmed 2006). Despite the lack of evidence, Vanzetta et al. showed that hydration is a common recommendation for patients after a dural procedure, estimating that 90% of interviewed centres recommend this method to prevent the onset of headache (Vanzetta 2005).

How the intervention might work

Prophylactic resting may have a similar mechanism of action as has been proposed for therapeutic immobilisation after the development of PDPH. CSF leakage is thought to be fundamental in the development of PDPH. Therefore, postures such as a prone position after a lumbar puncture may reduce hydrostatic pressure thereby reducing pressure in the subarachnoid space and allowing a seal to form over the dura, thus enabling CSF leakage repair. As such, this posture may be effective in preventing PDPH onset.

Hydration may work by replacing corporal fluid lost and increasing CSF production (Ahmed 2006). The increase in CSF production would replace lost CSF fluid, preventing a hydrostatic pull on pain‐sensitive structures and vasodilation (Janssens 2003). By this mechanism hydration may prevent the development of PDPH.

Why it is important to do this review

Lumbar puncture is a common clinical practice despite potential adverse effects (Evans 2009; Grande 2005). The morbidity associated with CSF loss, outside of PDPH, includes peripartum seizures, cranial subdural hematomas and subdural fluid collections (Arendt 2009). PDPH may be the first link in a chain of adverse events that are avoidable by following a series of simple recommendations (Janssens 2003). Patient immobilisation and oral intake of fluids may be valuable recommendations to avoid deleterious complications. Even though most cases of PDPH resolve within a few days, a significant number of patients have at least one week of disability, while others require prolonged or recurrent hospitalisations (van Kooten 2008).

A 2002 Cochrane Review related to these preventative strategies was undertaken by Sudlow and Warlow and included published and unpublished literature up to the year 2000 (Sudlow 2002). It is imperative that these results be updated in order to generate relevant and current recommendations for consumers, patients, and health practitioners.