Journal of Obstetric Anaesthesia and Critical Care

: 2011  |  Volume : 1  |  Issue : 2  |  Page : 57--66

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

Gita Nath, Maddirala Subrahmanyam 
 Department of Anaesthesia and Intensive Care, Axon Anaesthesia Associates, Hyderabad, India

Correspondence Address:
Gita Nath
834, Road No 43, Jubilee Hills, Hyderabad, AP 500033


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.

How to cite this article:
Nath G, Subrahmanyam M. Headache in the parturient: Pathophysiology and management of post-dural puncture headache.J Obstet Anaesth Crit Care 2011;1:57-66

How to cite this URL:
Nath G, Subrahmanyam M. Headache in the parturient: Pathophysiology and management of post-dural puncture headache. J Obstet Anaesth Crit Care [serial online] 2011 [cited 2017 Jun 26 ];1:57-66
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Childbirth is a life-changing experience, with profound physical, social as well as psychological effects on the mother. Headache is one of the most common complaints encountered in the delivery suite, with an incidence ranging from 11 to 80% of parturients. [1],[2] Primary headaches such as migraine, tension and cluster headaches [3] may be worsened by factors such as sleep deprivation, hormonal changes associated with parturition, dehydration, emotional lability and irregular food intake. The increasing use of regional techniques for operative delivery as well as labor analgesia is associated with post-dural puncture headaches. Lastly, pregnancy-associated conditions such as pre-eclampsia and posterior reversible encephalopathy syndrome (PRES); and intracranial conditions such as cerebral venous thrombosis need to be identified and treated. Thus headache in the puerperal period often presents a diagnostic challenge to the anesthetic and obstetric teams.

In this review, the main focus will be on post-dural puncture headache (PDPH) - the pathogenesis, risk factors, prevention and management. In addition, other more sinister conditions will be touched upon, which need to be differentiated from PDPH so that they may be managed appropriately.

 Incidence and Causes of Postpartum Headache

The majority of headaches in the postpartum period may not be reported either because they are assumed to be normal in that situation, or because the patient may be discharged from hospital before the onset of the headache. A prospective study looking at 985 parturients found that 381 patients (39%) complained of headache. The majority of headaches were migraine, tension-type or of undetermined causes; 15 were incapacitating and 18 were post-dural puncture. [3] Migraine has been found to recur or appear for the first time in the postpartum period. [4] Stella et al looked at 95 women who were hospitalized with headache >24 h postpartum over a five-year period. Again, tension-type/migraine comprised the most common cause (47%), followed by preeclampsia/eclampsia (24%) and PDPH (16%). Focal neurological deficits necessitated cerebral imaging in 22 patients, 15 of these had abnormal findings. [5]

Regarding PDPH associated with neuraxial techniques, it has been established beyond doubt that dural puncture with larger needles is associated with a greater incidence of PDPH. By using progressively smaller needles, the incidence of headache following dural puncture has been brought down from 66% in the year 1898 using 17 and 18 G needles, [6] to 33-36% with 22 G Quincke needles [7],[8],[9] and 0.4 to 20% using smaller Quincke needles of 24 to 32 G in different studies. [10],[11],[12],[13] Changing the design of needle tips from cutting Quincke needles to pencil-point, so-called atraumatic type such as Whitacre, Sprotte and Atraucan needles further reduced the incidence to 0-10%. [14],[15],[16],[17] A head-to-head comparison of Quincke and pencil-point needles of the same size (27 G, 0.40 mm O.D.) found PDPH incidences of 8.1 and 1.9%; and a meta-analysis of 1131 patients gave a relative risk of developing PDPH of 0.38 (95% CI from 0.19 to 0.75) in the pencil-point group compared to the Quincke group. [18] A similar study comparing 27-gauge (0.41-mm) Whitacre and Quincke spinal needles in 529 non-obstetric patients having out-patient surgery found the incidence of PDPH in the Quincke group to be 2.70%, while in the Whitacre group it was only 0.37% (P < 0.05). [19] The use of smaller needles is, however, associated with greater technical difficulties, which in turn may lead to multiple attempts, leading to a higher incidence of PDPH. [20],[21] Other risk factors for PDPH are female sex, younger age group and obstetric population, [22],[23] but a prospective study of over 1000 young patients found a PDPH incidence of only 0.8% using 24 G Sprotte needles with a low incidence of puncture difficulties. [24] Dural puncture with epidural needles is expected to cause a much greater incidence of headache, of much greater severity.

 PDPH with Different Neuraxial Techniques in Obstetric Patients

Spinal anesthesia

The main factor determining the frequency of PDPH following spinal anesthesia is the size and design of the needle. A large meta-analysis of obstetric studies dealing with PDPH found that with smaller, atraumatic needles, the risk of PDPH decreases but is still present. [25] Their findings on the types of needles which had enough studies to be pooled together, and on all epidurals together are summarized in [Table 1].{Table 1}

The National Obstetric Anaesthetic Database (NOAD) which included 65,348 women who had anesthetic interventions in the UK during the year 1999 reported a PDPH incidence of 1.9% after spinal anesthesia. [26] However, these results are not easy to achieve, and more recent reports from developing countries found higher incidences of PDPH (4.7, 8.3 and 23%) mainly due to the use of Quinke needles. [27],[28]

Epidural anesthesia/analgesia

The incidence of PDPH after epidural has ranged from 0.5 to 1.7% [26],[29],[30],[31] but was as high as 4.2% in one study. [32] The primary cause is accidental dural puncture (ADP) which may be recognized during the procedure; but up to nearly 40% of inadvertent dural punctures are only recognized by the onset of PDPH. Paech et al, in their audit of 100 parturients who experienced accidental dural puncture by a Tuohy needle, report that 27 were unrecognized at the time of puncture. [33] Similarly, Van de Velde reports 89 dural punctures in their series of 965 epidurals and 16193 combined spinal-epidurals, out of which 34 were not recognized. [29] In the NOAD database, 79 of 133 punctures were unrecognized. An interesting point is that 79% of the accidental dural punctures occurred in patients in labor. [26]

Following dural puncture with a Tuohy needle, the incidence of PDPH ranges from 52% [34] to 88%. [31],[35] The incidence and severity of the headache are decreased and success rates of treatment with a blood patch are improved by using 17 or 18 G Tuohy needles rather than 16 G, as shown in [Table 2]. [26],[31],[37]{Table 2}

Combined spinal-epidural

Intuitively, the incidence of ADP and PDPH with combined spinal-epidural technique would be expected to be similar or greater compared to epidural technique alone. An early pilot survey of 300 women given CSE for labor analgesia found that ADP occurred in 3 patients while 7 developed PDPH (2.3%). [38] This study used a single space needle through needle technique in the lateral position, and had an inadvertent dural puncture rate of 1%. There was also a 10.6% failure rate at getting CSF through the long 27 G atraumatic needle, possibly because of the sagging midline crease and lower CSF hydrostatic pressure. In the subsequent 1565 women receiving CSE in the same unit, the ADP rate decreased to 0.45% and PDPH to 0.58%. Failure to obtain CSF occurred in 5.3%. [39] More recently, in a large retrospective analysis of 6497 cases comparing epidural and CSE (needle-through-needle) techniques for labor analgesia, PDPH occurred in 0.8 and 1.4% of the epidural and CSE groups respectively. [30] Another retrospective analysis of 3519 elective cesarean sections using the double-space CSE technique found an ADP rate of 0.7% (1:141) with a 52% incidence of severe PDPH. [37]

The choice between epidural and CSE techniques for labor is a somewhat contentious issue. With the needle-through-needle technique, technical problems are often encountered, such as difficulty in obtaining CSF which may necessitate multiple dural punctures with the spinal needle, difficulty in immobilizing the spinal needle in the epidural needle and difficulty in threading the epidural catheter after the intrathecal injection. Intravascular puncture with the epidural catheter puts one in a difficult situation as withdrawing the catheter through the needle risks transaction of the catheter. This necessitates a fresh attempt at inserting the epidural, which may be a problem if the CSE is for a cesarean section, as the intrathecal injection would have already been given. These problems may be overcome if the double-space CSE technique is used, but since essentially the epidural puncture is being performed twice; all the risks of epidurals, including ADP and PDPH are doubled.

On the other hand, CSE technique gives better maternal satisfaction, especially in advanced labor. [30] Obtaining CSF through the spinal needle is also a good confirmatory test of the correct location of the epidural needle, hence reducing the failure rate. [32] Several factors associated with the CSE technique mitigate against PDPH such as the presence of the epidural catheter and solution in the epidural space reducing CSF leakage and intrathecal or epidural opiates which have a prophylactic effect. [40] A meta-analysis of 19 trials including 2658 women, comparing CSE with epidural for labor analgesia, found that CSE had a faster onset of effective analgesia and less need for rescue analgesia. There was also less urinary retention but was associated with more pruritus. However, a Cochrane review found no significant difference in the number of patients receiving blood patch for PDPH between the two techniques. [41] There are departments where over 90% of neuraxial blocks for obstetric indications are CSEs. [42]

To sum up, CSE may be used for cesarean section if the procedure is likely to be more complicated or prolonged. For labor analgesia, CSE is useful to obtain rapid analgesia for the patient who is in advanced labor. For routine labor analgesia, using CSE is a matter of individual preference, though the greater cost of CSE compared to epidural alone must also be a consideration.

 Management of Accidental Dural Puncture

Till the 90s, when accidental dural puncture occurred, it was the usual practice to remove the needle and re-site the epidural. An alternative method of managing ADP by passing an epidural catheter through the needle into the subarachnoid space was described by Cohen in 1989. [43] A 1993 survey of maternity units in the United Kingdom found that the epidural catheter was resited in 99% of them. [44] Since then, several studies have claimed a reduction in incidence of PDPH if the epidural catheter is inserted intrathecally at the time of dural puncture and removed after at least 24 h. [45],[46] A similar survey done 10 years later found that 85% of units have written guidelines for the management of ADP. Intrathecal catheterization was done in 28% of units, catheter was re-sited in 41% and either option was allowed in 31%. [47] [Table 3] compares the PDPH rate of intrathecal catheterization with re-siting the epidural. [29],[32],[43],[45],[46],[47],[48],[49],[50],[51],[52],[53],[54],[55],[56] A statistically significant advantage was found in four of the studies. [45],[49],[50],[55] Injection of a 10 ml bolus of normal saline into the intrathecal catheter before its removal further reduced the incidence of PDPH. [57] {Table 3}

More recent surveys have found that 25-36% of accidental dural punctures are managed by intrathecal catheter insertion. [58],[59],[60] The most common reason for not doing so was concern regarding the safety of intrathecal catheters, in particular, the risk of misuse. [60] The other risk, of course, is of infection, as exemplified by a case of meningitis following intrathecal catheterization. [61] Surprisingly, a 23-year survey of ADP and PDPH in a district general hospital in UK does not mention intrathecal catheterization after ADP. [36] If intrathecal catheters are used, they should be managed with strict adherence to clear policies and protocols, with close follow-up of patients by the anesthetic team. Analgesia can be managed with local anesthetics and opiates at much lower doses, after clearly labeling the catheter about its intrathecal location.

Pathophysiology of post-dural puncture headache

The spinal duramater, which extends from the foramen magnum to the second sacral vertebra, is composed of layers of collagen and elastic fibers. Traditional teaching is that the fibers are arranged longitudinally; hence needles inserted with their bevel oriented parallel to these fibers, separating rather than cutting them, would leave a smaller defect. [62],[63] However, recent electron and light microscopic studies show that though the outer dural fibers are longitudinally oriented, this arrangement is not repeated in all the layers. [64] Also, the posterior dural thickness is variable between individuals and in different areas in the same individual. [65]

About 500 ml of CSF is produced per day (21 ml/h); and at any time, and the volume of CSF ranges from 125 to 150 ml, half of which is intracranial. The lumbar CSF pressure is 5-15 cm water but increases to 40 cm water in the upright position. PDPH is thought to be caused by CSF leakage through the dural puncture at a greater rate than its production leading to a fall in CSF pressure. [66] This causes headache by two mechanisms. One is the sagging of the intracranial structures in the upright position; with traction on the meninges, cranial nerves and upper cervical nerves causing frontal, occipital and cervical pain. The second mechanism is compensatory vasodilatation in response to the low intracranial pressure which again causes headache. [67] The upright position worsens the headache by further decreasing the intracranial pressure and also by increasing the rate of loss of CSF through the dural puncture.

An experimental study done in 1923 found that defects made in the cranial dura of dogs took about one week to close. [21] Further, fibroblastic proliferation necessary for dural repair was promoted by the presence of blood clot and surrounding tissue damage. Thus a clean cut takes longer to heal than a more traumatic one. [68] This may explain the reduced incidence of PDPH with pencil-point needles, which may cause more tissue reaction than cutting needles. Similarly, retaining an intrathecally placed catheter for 24 h or more may cause tissue reaction and fibroblastic proliferation, helping to close the dural defect.

Accidental dural puncture manifests as efflux of CSF in the majority of cases, but the fact that a significant number are unrecognized at the time of puncture needs some explanation. CSF comes out through the epidural needle if the needle pierces the dura as well as the arachnoid mater so that all or part of the hole is in the subarachnoid space. But if the needle damages the dura without breaching the arachnoid, the dural puncture may go unnoticed. The catheter may then be inserted into the epidural space, the intrathecal space or into the so-called "third space to go astray" - the subdural space, which may be associated with delayed subarachnoid migration of the catheter tip. [69] The ADP may be recognized because of an excessive response to a test dose, aspiration of CSF through the catheter or by the development of PDPH. The chances of dural damage may be increased by multiple attempts or even by rotating the needle while it is in the epidural space, since it has been shown that less force is required to puncture the dura while the needle is rotated; [70] and the incidence of dural puncture with the catheter during CSE rose from 3 to 30% when the needle was rotated after the spinal injection. [71] It may be mentioned here that PDPH due to ADP is greater, by an order of magnitude, in incidence as well as severity compared to headache following spinal anesthesia; hence the results of studies combining both causes of PDPH can be contradictory and confusing.

Clinical presentation

The International Headache Society describes PDPH as headache that worsens within 15 min after sitting or standing and improves within 15 min after lying, with at least one of the following - neck stiffness, tinnitus, hypacusia, photophobia or nausea. There should be a history of dural puncture, the headache should develop within five days after dural puncture and should resolve either spontaneously within one week or within 48 h after effective treatment of CSF leak (usually by epidural blood patch). [72]

The majority of PDPH present within 48-72 h of the procedure, [73] but early discharge from the hospital means that the patient may be at home when the headache begins. A meta-analysis by Choi showed that the onset of PDPH is usually 1-7 days after the puncture, [25] but it has presented immediately, [74] as well as up to 12 days later. [75] The usual duration was 1-7 days [25] but have been reported to persist for up to 9-12 months following dural puncture. [76],[77],[78],[79]

Cranial nerve palsies have also been associated with PDPH, the most common nerve affected (92-95%) is the abducens, causing diplopia. The oculomotor and trochlear nerve may also be involved. The onset of diplopia is usually 4-10 days after dural puncture, usually preceded by PDPH. EBP is not very effective at treating diplopia, recovery occurs spontaneously in two weeks to eight months. [80] Trigeminal and facial nerve palsies; and auditory nerve affectation with hearing loss or tinnitus and post-partum blindness have all been reported to be associated with PDPH. [81],[82],[83],[84]

Untreated PDPH has been associated with intracranial complications which are uncommon but can be life-threatening. With the low intracranial pressure, bridging veins between the brain and dural sinuses may be stretched and ruptures in their most fragile portion which is in the subdural space. [85] Several cases of subdural hematoma following PDPH have been reported in the literature. Zeidan et al reviewed this topic and found 25 cases of cranial subdural hematoma following spinal anesthesia and 21 cases after ADP; these cases were diagnosed from 6 h to 29 weeks after dural puncture. The presentation was a change in the postural nature of the headache with or without other symptoms such as disorientation, hemiplegia and convulsions. [86]

Cerebral venous thrombosis, though rare in developed countries, is more common in the developing world, and incidences of 200-500 per 100,000 deliveries have been reported in India compared to 10-20 per 100,000 in Western countries. [87] Mortality has been reported as 28-33%, though with appropriate anticoagulation and good supportive treatment, it can be reduced to under 20%. [88] Dehdration along with the procoagulant state of pregnancy is believed to predispose to this condition, but associated thrombophilia should be considered. Stocks et al report a patient who had ADP and PDPH and was treated twice with epidural blood patching; both times her symptoms were resolved. She had 4 grand mal seizures the next day and MRI revealed cortical venous thrombosis. [89]

The term reversible cerebral vasoconstrictive syndromes refers to headache caused by cerebral vasoconstriction which presents as sudden-onset severe headache - so-called "thunderclap" headache for which a precipitating cause may or may not be found. There may be associated neurological deficits or seizures; and a strings and beads appearance is seen on angiography. These headaches are usually self-limiting but in one series of 67 patients, subarachnoid hemorrhage occurred in 22%, intracerebral hemorrhage in 6%, seizures in 3% and posterior leukoencephalopathy in 9%. In 63% of patients, the headaches were post-partum or precipitated by various vaso-active substances. [90]

Thus, PDPH can mimic several intracranial conditions such as cerebral venous sinus thrombosis, cerebral ischemia/infarction, space occupying lesion, subdural hematoma and subarachnoid hemorrhage. Though these conditions are uncommon, a high index of suspicion is necessary to avoid delays in management. Patients with persistent headaches should be assessed with a structured, systematic approach. Hypertension and proteinuria point toward preeclampsia and headache in these patients may herald impending eclampsia. Headache with postural variation along with the history of a neuraxial procedure indicate a post dural puncture headache and these patients should be managed as discussed above. If a second EBP is unsuccessful in relieving the headache, the patient should have a neurological assessment. Indications for neuroradiological imaging are continuous refractory headache, loss of its postural character, focal neurological signs and seizures not related to preeclampsia/eclampsia. CT scan may or may not be informative; MRI especially magnetic resonance angiography or venography (MRA and MRV) have better discriminative value. [91]


Technical aspects in performing the neuraxial block have a great influence on the occurrence of PDPH. Using the smallest gauge needles practicable is the first step in preventing PDPH. For spinal blocks, pencil point needles of 25 G or smaller should be used, especially in the obstetric population. Very small needles, less than 27 G, are associated with technical difficulties and higher incidence of failure, necessitating multiple punctures which again increases the incidence of PDPH. For epidurals, 18 G or smaller Tuohy needles should be used, since the PDPH associated with accidental dural puncture is less. The use of ultrasound to guide epidural placement, especially when there is expected difficulty, may avoid multiple attempts. [92] In a study of 300 patients, pre-procedure ultrasound caused a significant reduction in puncture attempts and side effects and better quality of analgesia. [93] Another study by the same group found that success rate in the first 60 attempts at obstetric epidural insertion by a group of residents was significantly higher with ultrasound guidance compared to conventional technique. [94]

Orienting the bevel of the needle to be parallel to the fibers has been shown to reduce CSF leakage; hence, if Quincke needles are used at all, they should be oriented in this way. If identification of the epidural space is done with this orientation, the needle will have to be rotated before inserting the catheter. It has been shown that it requires much less force to punch a hole in the epidural space while rotating the needle; [70],[95] therefore, epidural needles should be inserted with the bevel facing up or down. There is evidence that using saline rather air for epidural insertion lowers the incidence of PDPH. [96],[97] With air, the headache has an earlier onset and could be visualized with imaging. [98] There are several case reports of pneumocephalus ADP using loss of resistance to air, even when the epidural insertion was apparently uneventful, without an obvious dural puncture. [99],[100],[101]

After ADP, some studies advocated the administration of a prophylactic blood patch through the epidural catheter before its removal, to reduce the incidence of PDPH. [102],[103],[104] However, a randomized controlled trial did not show a reduction in PDPH incidence though a prophylactic EBP did reduce the duration and severity of the headache. [105] Some authors feel that EBP should be offered only when the onset of PDPH justifies the possible morbidity of the blood patch.

Epidural saline infusion is another intervention which was advocated in the 70s at rates of 1 to 1.5 L/day to increase the epidural pressure in order to reduce the CSF leak. [106],[107] However, this rise is not sustained and comparison of epidural saline and blood showed that epidural saline is not effective in the long term. [108] A bolus of saline has also been advocated to raise the epidural pressure, but this carries the danger of an excessively high block or a total spinal, especially after a prolonged local anesthetic infusion. [109]


Conservative treatment

Maintenance of hydration and prescription of simple analgesics should be done in all patients. Bed rest per se has no effect on the outcome but many patients may prefer to lie down in the position of their choice. An abdominal binder raises the intra-abdominal and CSF pressure and may provide some relief; but wearing it is uncomfortable and is not in general use.

Pharmacological treatment

The fact that so many agents have been proposed for the treatment of PDPH shows how difficult it is to treat it when really severe. One report published in 1964 listed 49 methods of treating PDPH. [110]

Caffeine is a CNS stimulant which also has a cerebral vasoconstrictive effect. Single doses of intravenous [111] as well as oral caffeine [112],[113] (250 mg and 300 mg respectively) have been shown to relieve mild PDPH but the effect is transient. It is available in combination with paracetamol in tablet form (paracetamol 500 mg with 30 to 50 mg of caffeine) and can be given round the clock for about a week to allow the dural puncture to heal. A structured evidence-based clinical neurologic practice review by three academic institutions found no valid pharmacological rationale for caffeine as an antinociceptive agent for PDPH. [114] Caffeine occasionally is associated with post-partum seizures. [115]

Sumatriptan is a 5-HT agonist with cerebral vasoconstrictive effects. It is used in the treatment of migraine and has been found useful for PDPH [116],[117] though a later controlled trial recruiting parturients with severe PDPH found only one in five reported less severe headache after either subcutaneous sumatriptan 6 mg or placebo. [118] Sumatriptan is excreted in breast milk and it is advised that breast feeding should be avoided for 12 h following exposure to this drug. Frovatriptan has been found effective in PDPH at 2.5 mg/day for 5 days. [119]

Cosyntropin or synthetic ACTH, and hydrocortisone are believed to work by stimulating the adrenal gland and increasing CSF secretion. Intravenous cosyntropin [120] as well as hydrocortisone [121] have been found to be effective in treating PDPH after failed EBP. In a randomized controlled study of 60 patients with PDPH following spinal anesthesia for cesarean section, hydrocortisone given for 48 h significantly reduced the severity of PDPH in the study group. [122] In another randomized controlled study of 90 patients with ADP, Cosyntropin 1 mg IV reduced PDPH from 69 to 33%; and the need for EBP from 30% to 11%. [123]

 Epidural Blood Patch

After the observation that "bloody taps" were associated with less headaches, the concept of epidural blood patch was introduced by Gormley and popularized by Di Giovanni. [124],[125] When autologous blood is injected into the epidural space, it spreads both cephalad and caudal and increases the pressure in the epidural space, compressing the thecal sac and increasing the CSF pressure. This causes immediate relief of the headache. At the same time, the blood coagulates, helped by the procoagulant effect of the CSF, and occludes the hole in the dura, preventing further leakage of CSF. The mass effect gradually resolves over 7-13 h, leaving a mature clot in the posterior epidural space. [126] Over the next few days, there is fibroblastic activity and collagen formation, further securing closure of the dural perforation. [21]

The EBP should be performed only after excluding contraindications such as fever, local infection, coagulopathy or patient refusal. It is also important to evaluate the patient carefully so that the diagnosis of PDPH is not in doubt. Some authorities recommend sending a blood culture at the same time. [127] Under full aseptic precautions, with the patient usually in the lateral position, the epidural space is identified, either at the level of original puncture or one space lower. Another anesthetist, also with full aseptic precautions, performs venepuncture and hands over the blood to be injected. The volume of blood to be injected is usually 20 ml though some people inject up to 30 ml. It is slowly injected into the epidural space till the patient reports a feeling of pressure or pain in her back or legs. After the procedure, the patient is advised to lie flat for at least 2 h and avoid vigorous activity or straining for a few days.

It is recommended that the EBP should not be performed too soon after dural puncture. A randomized study by Loeser found that performing EBP after 24 h reduced the failure rate from 71% to 4% in a study of 66 EBP. [128] The initial outcome from an EBP is between 70 and 98% but up to 40% need a second EBP, and occasionally even a third. [129],[130] Complications following EBP include backache, transient bradycardia, radiculitis, arachnoiditis, aseptic meningitis, cranial nerve paralysis, seizures and cauda equina syndrome. A case of permanent spastic paralysis cautions us that EBP is not a completely benign procedure. [131] A recent Cochrane review concluded that EBP is beneficial for PDPH compared to conservative treatment. [132] It should be remembered that PDPH is not only a disabling condition but, if left untreated, can also lead to complications such as cranial nerve palsies, subdural hematoma and cortical venous thrombosis.


Post dural puncture headache is one of the major causes of headache in the postpartum period. 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. Accidental dural puncture has a 55-80% incidence of PDPH. Current evidence is in favor of intrathecal catheterization, using the catheter for analgesia/anesthesia and removed after at least 24 h, after injecting a 10 ml bolus of saline. Written protocols for the management of accidental dural puncture help to reduce the incidence of PDPH.

Severe untreated PDPH can cause complications such as nerve palsies, subdural hematoma and cerebral venous thrombosis. Conservative methods of treatment include adequate hydration, paracetamol, caffeine, sumatriptan and ACTH/hydrocortisone. Epidural blood patching is the most effective treatment for PDPH. It is more effective if done in 24-48 h 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 block may be needed. 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 anesthetic 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 neuro-radiological imaging.


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