prophylactic blood patch

Original Article

Prophylactic vs therapeutic blood patch for obstetric patients with

accidental dural puncture – a randomised controlled trial

M. H. Stein,1 S. Cohen,2 M. A. Mohiuddin,3 V. Dombrovskiy4 and I. Lowenwirt5

1 Associate Professor, 2 Professor, 3 Research Assistant, Department of Anesthesia, 4 Assistant Professor, Departmentof Surgery, Rutgers, The State University of New Jersey- Robert Wood Johnson Medical School, New Brunswick,New Jersey, USA5 Clinical Assistant Professor, Department of Anesthesia, New York Hospital Queens, Flushing, New York, USA

SummaryEpidural blood patch is a standard treatment for obstetric patients experiencing a severe post-dural puncture head-

ache. Patients who sustained an accidental dural puncture during establishment of epidural analgesia during labour

or at caesarean delivery were randomly assigned to receive a prophylactic epidural blood patch or conservative treat-

ment with a therapeutic epidural blood patch if required. Eleven of 60 (18.3%) patients in the prophylactic epidural

blood patch group developed a post-dural puncture headache compared with 39 of 49 (79.6%) in the therapeutic

epidural blood patch group (p < 0.0001). A blood patch was performed in 36 (73.4%) of patients in the therapeutic

group. The number of patients who needed a second blood patch did not differ significantly between the two

groups: 6 (10.0%) for prophylactic epidural blood patch and 4 (11.1%) for therapeutic epidural blood patch. We

conclude that prophylactic epidural blood patch is an effective method to reduce the development of post-dural

puncture headache in obstetric patients..................................................................................................................................................................

Correspondence to: M. H. Stein

Email: [email protected]

Accepted: 8 December 2013

IntroductionAccidental dural puncture is a recognised complication

of epidural anaesthesia in obstetrics, with the frequent

sequel of post-dural puncture headache [1]. Therapeu-

tic epidural blood patch (EBP) is a standard treatment

of post-dural puncture headache. However, the use of

prophylactic EBP in preventing the occurrence of a

post-dural puncture headache is controversial [2].

Some clinicians argue that not all patients with a dural

puncture develop a post-dural puncture headache, that

EBP has potential risk [3, 4] and that most cases of

post-dural puncture headache will subside spontane-

ously within one week [5].

Nevertheless, post-dural puncture headache can

have substantial symptomatology in the obstetric

population [6]. The headache can be incapacitating

and may be accompanied by diplopia, tinnitus, hypo-

acusis, photophobia, nausea, dizziness, nuchal rigidity

and myalgia. Additional complications reported

include cranial nerve palsies [7] and subdural haema-

toma [8, 9]. An otherwise successful and satisfactory

birth experience may be marred as a result, leading

to significant dissatisfaction with the anaesthesia

experience [10], litigation [11], prolonged hospital

stay [12, 13] and sequelae including chronic headache

[14].

320 © 2014 The Association of Anaesthetists of Great Britain and Ireland

Anaesthesia 2014, 69, 320–326 doi:10.1111/anae.12562

Large, well-organised and randomised controlled

studies are needed to establish the role of prophylactic

EBP. We present the results of a randomised con-

trolled trial of prophylactic EBP vs therapeutic EBP

designed to determine whether prophylactic EBP is

beneficial for patients with accidental dural puncture.

MethodsWe performed a prospective randomised controlled

study, beginning in 1997 and ending in 2005, of pro-

phylactic EBP vs therapeutic EBP in women who had

undergone accidental dural puncture during epidural

block for labour analgesia or caesarean delivery. Insti-

tutional Review Board approval was gained for the

study. Written informed consent was obtained from

the study subjects.

Inclusion criteria for the study were age between

15 and 45 years and ASA physical status 1–3. Exclu-

sion criteria were pre-existing or pregnancy-induced

hypertension, recurrent headache requiring treatment

in the last six months, seizure disorder, or more than

four cups of coffee per day in the week preceding

delivery.

After performing an accidental dural puncture

during epidural placement, the anaesthetist repeated

the attempt one interspace cephalad to the first

attempt and secured the catheter. For women in

labour, the woman was informed about the occurrence

of the accidental dural puncture and study consent

obtained once satisfactory analgesia was established

and she was stable with normal maternal and fetal

vital signs. In women having caesarean delivery, she

was informed about the occurrence of the dural punc-

ture and the study when she was stable in the post-

anaesthesia care unit. Using a random number table,

eligible parturients were then allocated to prophylactic

or therapeutic EBP.

Subjects assigned to prophylactic EBP received 15–

20 ml autologous blood [15–18] through the indwell-

ing epidural catheter at least 5 h following the last

dose of epidural local anaesthetic [3, 19–21] and were

kept supine for 1 h [22]. The epidural catheter was

then removed.

If subjects in the therapeutic EBP group developed

headache, they were initially managed conservatively

with one or more of the following, based on the clini-

cian’s preference: caffeine (500 mg intravenously, with

a second dose if needed 1 h later and supplemental

doses every 8 h [23–25]); saline patch (15–20 ml saline

0.9% through the indwelling epidural catheter 4–5 h

following delivery [26, 27]); patient-controlled epidural

analgesia for women who had a caesarean delivery

(ropivacaine 0.025%, fentanyl 3 lg.ml�1 and adrena-

line 1 lg.ml�1 at 15 ml.h�1, 4-ml bolus and 10 min

lockout), aminophylline (300 mg orally every 12 h [28,

29]), paracetamol (1 g every 6 h) or oxycodone

10 mg/paracetamol 325 mg (two tablets every 6 h).

We used the International Headache Society defi-

nition of post-dural puncture headache as a positional

headache with at least one of five accompanying symp-

toms (nuchal rigidity, tinnitus, hypoacusis, photopho-

bia, nausea) [6]. If post-dural puncture headache

persisted despite these measures, patients were offered

a therapeutic EBP. This was performed using 15–

20 ml autologous blood, following which the patient

was kept supine for 1 h.

An independent blinded observer evaluated all

patients at 12-h intervals while they were in hospital,

and by a telephone call daily for one week after dis-

charge [16]. Patients were instructed to contact the

Department of Anaesthesia if they developed a post-

dural puncture headache at any time thereafter.

Onset, frequency and severity of headache, nuchal

rigidity, tinnitus, photophobia, diplopia, nausea, vomit-

ing, effectiveness of conservative treatment, need for a

second EBP, duration of hospital stay and need for a

return visit to the Emergency Department were

recorded. Headache was graded on a 4-point scale

(mild, postural headache causing slight restriction of

daily activity, with no associated symptoms; moderate,

postural headache causing the patient to be confined

to bed rest part of the day, with no associated symp-

toms; severe, postural headache causing the patient to

be bedridden all day, with associated symptoms) [30].

Treatment failure was defined as severe headache

requiring first or repeat EBP, or patient request for

EBP regardless of headache severity.

A power analysis was performed using post-dural

puncture headache as the primary outcome. Forty-

three patients were required in each group to detect a

decrease in the incidence of post-dural puncture head-

ache from 70% to 40%, with a power of 80% and

© 2014 The Association of Anaesthetists of Great Britain and Ireland 321

Stein et al. | Prophylactic vs therapeutic blood patch Anaesthesia 2014, 69, 320–326

p ≤ 0.05. The incidence of post-dural puncture

headache in the two groups was compared with chi-

squared analysis or Fisher’s exact test, when appropri-

ate, for categorical variables and Student’s t-test or

non-parametric Wilcoxon rank-sum test for continu-

ous variables. A p value < 0.05 was considered signifi-

cant. Data analysis and statistics were performed with

SAS� 9.3 statistical software (SAS Institute, Cary, NC,

USA).

ResultsFigure 1 shows the CONSORT diagram of study

recruitment. Sixty patients were randomly allocated to

the prophylactic EBP group and 56 to the therapeutic

EBP group. Seven patients in the therapeutic EBP

group were randomly allocated erroneously and subse-

quently not studied, leaving 49 in the group.

Age, weight, height and body mass index within

each group were normally distributed, and median

parity was the same in each group (Table 1). The

median (IQR [range]) time from dural puncture until

administration of the prophylactic EBP was 8 (6–13

[5–30]) h. The mean (SD) time from dural puncture

until onset of symptoms was 37.9 (34.8) h in the pro-

phylactic EBP group and 31.5 (24.2) h in the therapeu-

tic EBP group (NS).

The frequency of headache in the prophylactic

EBP group was significantly less than in the therapeu-

tic EBP group (Table 2). Among patients with head-

ache in the therapeutic EBP group, the majority were

Assessed for eligibility (n = 140)

Excluded (n = 24) Not meeting inclusion criteria (n = 24) History of hypertension or recurrent headache (n = 24) Declined to participate (n = 0)

Randomised (n = 116)

Prophylactic blood patch (n = 60) Conservative treatment (n = 56)

Headache (n = 11) No headache (n = 49)

Second blood patch (n = 6)

No further complaints after one week (n = 6)

Headache (n = 39) No headache (n = 10)

Second blood patch (n = 4)


Therapeutic bloodpatch (n = 36)




Conservative treatment (n = 49)

Excluded (n = 7) Failure to randomise (n = 7)

Figure 1 CONSORT diagram of study recruitment.


Anaesthesia 2014, 69, 320–326 Stein et al. | Prophylactic vs therapeutic blood patch

rated moderate or severe. The most common addi-

tional symptoms specific for PDPH [6] included

nuchal rigidity and tinnitus. Table 3 shows the

pharmacological treatments used in 39 patients in the

therapeutic EBP group who developed a headache.

Six (10%) patients in the prophylactic EBP group

required a second EBP. All of them had a vaginal

delivery. Five of these had their second EBP performed

in the Emergency Department on a return trip to hos-

pital. Thirty-six (73.4%) patients in the therapeutic

EBP group received an EBP. Four of these had the

EBP in the Emergency Department on a return trip to

hospital. Four of the 36 (11.1%) received a second

EBP, performed in the Emergency Department on a

return trip to hospital. There were a total of five

(8.3%) Emergency Department visits after hospital dis-

charge in the prophylactic EBP group and nine

(18.4%) in the therapeutic EBP group (p = 0.15); only

one visit in the latter group did not result in an EBP’s

being administered. The mean (SD) length of stay in

hospital was 71.3 (30.2) h in the prophylactic EBP

group and 81.5 (38.8) h in the therapeutic EBP group

(p = NS).

DiscussionSeveral reviews [5, 31–33] have analysed previous stud-

ies of EBP for post-dural puncture headache and

attempted to account for the heterogeneity of the

results. Some studies did not withstand statistical scru-

tiny, others were procedurally flawed, and still others

seemed clinically irrelevant to modern practice.

In this study, we attempted to address some of the

confounding factors and objections raised in those pre-

vious reports. This study was randomised and prospec-

tive, with a sufficient number of patients for statistical

power, but it was not double-blind. Clinicians knew

that they were performing EBP or administering other

Table 1 Characteristics of patients receiving prophy-lactic or therapeutic epidural blood patch. Values aremean (SD) or median (IQR [range]).

Prophylactic(n = 60)

Therapeutic(n = 49)

Age; years 28.8 (5.5) 31.7 (5.2)*Weight; kg 79.2 (15.0) 80.7 (19.1)Height; cm 161.1 (7.1) 159.8 (6.6)BMI; kg.m�2 30.5 (5.5) 31.5 (6.5)Parity 1 (1–2 [1–4]) 1 (1–2 [1–4])

BMI, body mass index.*p = 0.0074.

Table 2 Frequency and severity of headache in womenreceiving prophylactic or therapeutic epidural bloodpatch. Values are number (proportion).

Prophylactic(n = 60)

Therapeutic(n = 49) p value

Headache 11 (18.3%) 39 (79.6%) < 0.0001Severity score

Mild 2 (3.3%) 3 (6.1%) 0.49Moderate 4 (6.7%) 13 (26.5%) 0.004Severe 5 (8.3%) 23 (46.9%) < 0.0002

Accompanying symptomsNuchalrigidity

7 (11.7%) 27 (55.1%) < 0.0001

Tinnitus 1 (1.7%) 11 (22.4%) 0.001Photophobia 1 (1.7%) 4 (8.1%) 0.23Diplopia 0 3 (6.1%) 0.063Nausea 0 1 (2.0%) 0.45Vomiting 0 0 –

Table 3 Pharmacological treatments used in the 39women allocated to the therapeutic epidural bloodpatch group who developed a headache. Values arenumber (proportion).

No EBP(n = 3)

EBP(n = 36)

Caffeine 0 (0%) 1 (2.8%)Caffeine and oxycodone/paracetamol

1 (33.3%) 2 (5.6%)

Caffeine, PCEA andparacetamol

0 1 (2.8%)

Caffeine, aminophylline andoxycodone/paracetamol

0 1 (2.8%)

Caffeine, paracetamol andoxycodone/paracetamol

0 2 (5.6%)

Aminophylline 0 11 (30.5%)Aminophylline andparacetamol

0 1 (2.8%)

Aminophylline andoxycodone/paracetamol

0 3 (8.3%)

Paracetamol and oxycodone/paracetamol

0 3 (8.3%)

PCEA 1 (33.3%) 1 (2.8%)Epidural saline injection 1 (33.3%) 0Oxycodone/paracetamol 0 1 (2.8%)Epidural saline injection,paracetamol and oxycodone/paracetamol

0 1 (2.8%)

Patient-requested bloodpatch

– 8 (22.2%)

EBP, epidural blood patch; PCEA, patient-controlled epiduralanalgesia.



modalities, and patients knew if they received EBP. The

observer was blinded, and this helped to minimise

potential bias. Sham EBP was not performed. In a study

using sham injection down the epidural catheter,

patients were more likely to report feeling sacral pres-

sure when blood was injected compared with no injec-

tion [16]. We question whether this ‘tipped off’ patients

that they were receiving the blood injection and not

the sham. We did not bias our patients regarding the

benefits of either treatment protocol, and we asked all

nursing staff and obstetricians to do likewise.

Post-dural puncture headache was defined as per

the International Headache Society classification [6]

and graded according to a published classification [30],

in contrast to other studies with non-standard defini-

tion and grading. Failure to meet the International

Headache Society definition may have misled investi-

gators in previous studies. The mean age difference

between groups of 28.8 vs 31.7 years was statistically

significant, but not clinically relevant.

Prophylactic EBP was performed in accordance

with recognised practice. The procedure was per-

formed at least 5 h after the last dose of epidural

anaesthetic to prevent inhibition of coagulation by

residual local anaesthetic [19–21] or accidental total

spinal anaesthesia [3]. We used 15–20 ml autologous

blood [15–18] and ensured bed rest for 1 h after the

procedure [22]. We felt that adherence to this tech-

nique was an important factor in the success of pro-

phylactic EBP. The elapsed time from dural puncture

to prophylactic EBP varied owing to factors such as

the duration of labour.

No patient experienced any adverse effects from

the administration of a prophylactic EBP. As adverse

effects such as infection or neurological abnormalities

are rare and reports are anecdotal, more patients

would need to be studied to determine safety.

Patients in the therapeutic EBP group received one

of several treatments or combinations of treatments.

They did not receive a standardised treatment proto-

col, which might be viewed as a flaw in our methodol-

ogy. No one conservative method or combination of

methods could be assessed as superior to the others.

Epidural morphine may be a beneficial option [33, 34],

but was not performed. Use of an intrathecal catheter

for > 24 h may also hold promise [32, 35, 36].

A study by Scavone et al., comparing prophylactic

EBP with sham EBP, showed no significant difference

in onset time to post-dural puncture headache, median

peak pain scores, and number of days unable to per-

form childcare activities as a result of post-dural punc-

ture headache [16]. The authors concluded that

prophylactic EBP did not decrease the incidence of

post-dural puncture headache or the need for thera-

peutic EBP, although prophylactic EBP did shorten the

length and severity of post-dural puncture headache

symptoms. Our study also showed no significant dif-

ference in onset time to post-dural puncture headache

in the prophylactic vs therapeutic EBP groups, and a

decrease in severity of post-dural puncture headache

symptoms in the prophylactic EBP group, but showed

a significant decrease in the incidence of headache in

prophylactic vs therapeutic EBP groups.

A recent systematic review and meta-analysis on

prevention of post-dural puncture headache in parturi-

ents points out the difficulties in finding interventions

to reduce the incidence of accidental dural puncture

and post-dural puncture headache [33]. Although pro-

phylactic EBP is supported in some studies, flawed

methodology in each of those studies prevents prophy-

lactic EBP from being embraced as a practice recom-

mendation. Epidural morphine and administration of

cosyntropin were each supported in single randomised

control trials [33].

Prophylactic EBP combined with other treatment

modalities might possibly reduce the incidence and

severity of post-dural puncture headaches further, and

such studies remain to be carried out. Reducing the

incidence of accidental dural punctures would of

course be best. Better imaging methods to allow needle

guidance are needed [37].

We believe that important issues still remain in the

study of prevention and treatment of post-dural punc-

ture headache, such as the different clinical circum-

stances in which accidental dural puncture occurs.

There might be differences in the nature, severity and

likelihood of post-dural puncture headache depending

on whether the first and second stages of labour are long

and arduous vs shorter, whether labour is induced or

spontaneous, whether dural puncture follows elective

caesarean delivery, and the elapsed time between dural

puncture and EBP; decisions regarding prophylactic or



therapeutic intervention might be tailored accordingly.

Scavone et al.’s study [16] included a number-needed-

to-treat analysis, which revealed that eight patients

would need a prophylactic EBP to avoid a single thera-

peutic EBP. If subgroups of patients at lower or higher

likelihood of developing headache could be identified,

such information could guide clinicians and patients in

their treatment decisions.

The therapeutic/conservative alternatives offered to

control groups in EBP studies remain poorly standar-

dised. This was a flaw in our study as well as in other

studies [16]. Blinding all parties concerned also

remains a challenge.

In summary, prophylactic EBP decreased the inci-

dence of post-dural puncture headache after accidental

dural puncture in obstetric patients. The intensity of

the headache and accompanying symptoms were also

reduced. The optimal prophylaxis and treatment for

post-dural puncture headache remain to be deter-

mined.

Competing interestsNo external funding and no competing interests

declared.

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