++
Once the diagnosis has been made, patients should be provided a
straightforward explanation of the cause, natural history, and treatment
options for PDPH. A treatment algorithm, based primarily on the severity of
symptoms, can serve as a useful guide for management (Figure
73–1).
++
PDPH is a complication that tends to resolve spontaneously. Prior to
the introduction of definitive therapy for PDPH (ie, the EBP), the natural
history of the disorder was documented by Vandam and Dripps as they followed
1011 episodes of PDPH after spinal anesthesia using cutting needles of
various sizes.11 Although their analysis is flawed by a
lack information on duration in 9% of patients, if one considers their
observed data, spontaneous resolution of PDPH was seen in 59% of cases
within 4 days and 80% within 1 week. More recently, Lybecker and
coworkers followed 75 episodes of PDPH and, although providing an EBP to
40% of their patients, noted in the untreated patients a median duration
of symptoms of 5 days with a range of 1 to 12 days.2 These
data, although generally reassuring, also illustrate the sometimes prolonged
duration of untreated PDPH. Indeed, Vandam and Dripps noted 4% of
patients still experiencing symptoms 7–12 months after spinal
anesthesia.11 Similar observations of prolonged symptoms
have been reported following diagnostic lumbar puncture74
and ADP.75 A number of case reports exist of successful
treatment of PDPH months or years after known76 or even
occult dural puncture.77
++
Primarily due to the self-limited nature of PDPH, the optimal time
course of treatment has not been well-defined. Although many practitioners
have advocated 24–48 h of conservative therapy, the practicality of this
approach is questionable, given the often severely disabling nature and
prolonged duration of symptoms. Notably, the duration of PDPH appears to be
directly related to needle size,78 which would support
early definitive therapy for severe headaches following dural punctures made
with large (eg, epidural) needles.
++
Reassurance and supportive measures, although not expected to alter the
duration of symptoms, are advised for all patients. Most patients with
severe PDPH will naturally seek a recumbent position for symptomatic relief.
Although excessive hydration does not appear to influence the duration of
symptoms,59 patients should be encouraged to avoid
dehydration. Oral analgesics (acetaminophen, NSAIDs, or narcotics) may be
utilized, yet the relief obtained is often unimpressive, especially with
severe headaches. Antiemetics and stool softeners should be prescribed when
indicated. Abdominal binders can provide some degree of relief, but are
uncomfortable and seldom used in modern practice.
+++
Pharmacologic Treatments
++
A number of pharmacologic agents have been advocated as treatments for
PDPH.79 However, these options have generally been poorly
studied and are of questionable efficacy due to the small numbers of
patients treated, methodologic flaws in published reports, and the
self-limited nature of PDPH.
++
Methylxanthines are used for their cerebral vasoconstrictive effects and
include aminophylline,80 theophylline, and the best
studied, caffeine.79 Caffeine has been used intravenously
(500 mg caffeine sodium benzoate, which contains 250 mg caffeine) and orally
(300 mg). Published studies of caffeine used for PDPH consistently
demonstrate improvement at 1 to 4 h in over 70% of patients treated.
However, a single oral dose of caffeine for treatment of PDPH was
statistically no better than placebo at 24 h.81 With a
terminal half life of 6 h, repeated doses of caffeine would seem necessary
for treatment of PDPH; however, no studies have evaluated more than two
doses for efficacy or safety (of particular concern in the
breastfeeding patient). Furthermore, there is no convincing evidence that caffeine
reduces the eventual need for EBP. The temporary benefit observed with
caffeine would indicate that it is perhaps most useful for relief of
moderate symptoms while awaiting the spontaneous resolution of PDPH. The
familiarity of caffeine for nonmedical purposes would argue for its general
safety, but its use is contraindicated in patients with seizure disorders,
pregnancy-induced hypertension, or a history of supraventricular
tachyarrhythmias.
++
Sumatriptan, a serotonin type-1d receptor agonist that causes cerebral
vasoconstriction, is commonly used for migraine headache and has also been
used to treat PDPH. However, sumatriptan was not effective in a small
randomized, prospective study for treatment of severe
PDPH.82 Corticosteroidogenics (ACTH and its synthetic form,
cosyntropin/tetracosactin83) have also been proposed as
treatments for PDPH. Reports of the successful use of these agents are
intriguing, but their role in the management of PDPH awaits further study.
+++
Epidural Interventions
++
Bolus injections of epidural saline (usually 20–30 mL, repeated as
necessary if a catheter is present) have been reported to produce prompt and
virtually universal relief of PDPH, yet the practice is plagued by an
extremely high rate of headache recurrence. This transient effect is not
surprising as increases in epidural pressure following bolus administration
of saline have been shown to return to baseline within 10
min.84 Favorable results achieved with this approach have
been speculated to represent the mechanical reapproximation of a dural flap.
A combination of saline bolus followed by infusion has occasionally been
successful in the treatment of PDPH under exceptional
circumstances.85
++
However, bolus administration of saline for treatment of PDPH is of
questionable merit when compared with the EBP, especially when headaches are
secondary to large-bore punctures of the dura.86 Overall,
epidural saline appears to be of limited value for established PDPH.
+++
Epidural Blood Patch: When, Why, and How
++
During the past several decades, the EBP has emerged as the “gold
standard” of treatment for PDPH.44 This procedure has
been well-described and consists of a sterile injection of autologous blood
at or below the level of previous dural puncture (due to the preferential
cephalad spread of blood in the lumbar epidural space87).
The mechanism of the EBP, although not entirely understood, appears to be
related to the ability to stop further CSF loss by the formation of clot
over the defect in the dura as well as a tamponade effect with cephalad
displacement of CSF (the “epidural pressure patch”).88
++
A Cochrane Review (a systematic assessment of the evidence) of the EBP
recently concluded that the role of this procedure in the prevention and
treatment of PDPH was uncertain, primarily due to a lack of reliable
data.89 Reflecting this absence of adequately powered,
randomized trials, a number of controversies surround the
EBP.90
++
The optimal timing of the EBP is undetermined. A number of studies
suggest that the procedure becomes more effective with the passage of
time,91–93 but this observation may simply be due to
larger, harder to treat CSF leaks, which demand earlier attention. Although
prophylactic use of the EBP does not appear to be warranted, there is little
rationale for delaying EBP if symptoms are severe.
++
++
The ideal volume of blood for EBP is also unclear, as extensive epidural
spread is visualized with volumes greater than 10 mL.87
Currently, volumes of up to 20 mL are commonly employed, with the injection
stopped when the patient complains of discomfort or fullness in the back,
buttocks or head. There is no clear association between success rates for
EBP and volume of blood used (between 10 and 20 mL), and there are few data
to encourage the use of volumes greater than 20 mL.
++
Early observations of the EBP reported success rates well over 90%, but
the true efficacy of the procedure appears to be significantly lower.
Although the EBP is associated with nearly immediate symptomatic relief in
approximately 90% of cases, follow-up reveals a significant number of
patients experiencing incomplete relief, failure, and recurrence. In an
analysis of 504 patients receiving EBP following dural puncture with needles
of various sizes, Safa-Tisseront and colleagues noted complete relief in
75%, incomplete relief in 18%, and failure in
7%.92 PDPH secondary to needles larger than 20 gauge
were an independent risk factor for failure of EBP, an observation supported
by studies in obstetric patients following ADP with epidural needles. Under
these circumstances, Williams and colleagues noted complete relief of
symptoms with EBP in only 33% of patients, partial relief in 50%, and
no relief in 12%.94 If performed, a second EBP resulted
in complete relief in 50%, partial relief in 36%, and no relief in
14%. In a similar patient population, Banks and colleagues, despite
initially observing complete or partial relief with EBP in 95% of
patients, reported the return of moderate-to-severe symptoms in 31%, with
a mean time to development of recurrent headache of 31.8 h (range 12–96
h).93 The rates of repeat EBP for the Williams and Banks
studies were 27% and 19%, respectively. These studies clearly
demonstrate the reduced efficacy of the EBP following dural punctures made
with large needles, which will not uncommonly make it necessary for
clinicians to consider repeating the procedure. Success rates of a second
EBP appear to be equal to that of a first.
++
Following the successful performance of an EBP, maintenance of the decubitus
position for at least 1 and preferably 2 h may result in a more complete
resolution of symptoms.95 Avoidance of lifting, Valsalva
maneuvers, and air travel for 24 to 48 h are commonly advised to minimize
the risk of patch disruption. Finally, patients should be provided clear
instructions for the provision of timely medical attention should they
experience a recurrence of symptoms.
+++
Contraindications and Risks
++
Contraindications to the EBP are similar to those of any epidural
needle placement: patient refusal, coagulopathy, systemic sepsis, fever, and
infection at the site. Theoretical concerns have been expressed regarding
the possibility of neoplastic seeding of the central nervous system in
patients with cancer.96 Although not free of
controversy,97 the EBP has been safely provided to
patients with HIV infection98 and acute
varicella.99 The EBP may also be indicated and performed,
with decreased volumes of blood, in the pediatric
population100 and at extralumbar (eg,
cervical101) sites. Modifications of usual EBP technique
have been suggested to accommodate the special needs of Jehovah's Witness
patients.102
++
Minor side effects are common following the EBP. Patients should be
warned to expect aching in the back, buttocks, or legs (seen in
approximately 25% of patients).93 Although usually
short-lived, backache was noted to be persistent in 16% of patients
following EBP, lasting 3–100 days (with a mean duration of 27.7
days).103 Despite these lingering symptoms, patient
satisfaction with the EBP is high. Other frequent but benign after effects
of the EBP include transient neckache,103
bradycardia,104 and modest temperature
elevation.103 Significant risks of EBP are essentially the same as with
other epidural procedures (infection, bleeding, nerve damage, and ADP).
Occasionally, the temporary back and lower extremity radicular pain
mentioned earlier has been reported to be severe. With proper technique,
infectious complications are vanishingly rare. Although controversial, it
appears that a previous EBP does not significantly influence the success of
future epidural interventions.105 Serious complications
secondary to the EBP do occur but have usually consisted of isolated case
reports and have often been associated with significant deviations from
standard practice.44
++
Finally, a history of significant technical difficulties with attempted
central neuraxial techniques, although not a contraindication to epidural
treatments, should naturally encourage a trial of less invasive measures.
+++
Other Epidural Treatments
++
A variety of alternatives to blood have been promoted as patch
materials, including dextran-40,106 hydroxyethyl
starch,107 gelatin,107,108 and fibrin
glue.109 Although not without merit, these options remain
poorly defined, and reports of their use should be considered preliminary.