Efficacy of a prophylactic epidural blood patch in preventing post dural puncture headache in parturients after inadvertent dural puncture

BACKGROUND: Postdural puncture headache (PDPH) occurs in up to 80% of parturients who experience inadvertent dural puncture during epidural catheter placement. The authors performed a randomized double blind study to assess the effect of prophylactic epidural blood patch on the incidence of PDPH and the need for therapeutic epidural blood patch. METHODS: Sixty-four parturients who incurred inadvertent dural puncture were randomized to receive a prophylactic epidural blood patch with 20 ml autologous blood (prophylactic epidural blood patch group) or a sham patch (sham group). Subjects were evaluated daily for development of PDPH for a minimum of 5 days after dural puncture. Those who developed a PDPH were followed daily for a minimum of 3 days after resolution of the headache. Subjects with moderate headaches who reported difficulties performing childcare activities and all those with severe headaches were advised to receive a therapeutic epidural blood patch. RESULTS: Eighteen of 32 subjects in each group (56%) developed PDPH. Therapeutic blood patch was recommended in similar numbers of patients in each group. The groups had similar onset time of PDPH, median peak pain scores, and number of days spent unable to perform childcare activities as a result of postural headache. The median duration of PDPH, however, was shorter in the prophylactic epidural blood patch group. CONCLUSIONS: A decrease in the incidence of PDPH or the need for criteria-directed therapeutic epidural patch was not detected when a prophylactic epidural blood patch was administered to parturients after inadvertent dural puncture. However, prophylactic epidural blood patch did shorten the duration of PDPH symptoms.     

Efficacy of a Prophylactic Epidural Blood Patch in Preventing Post Dural Puncture Headache in Parturients after Inadvertent Dural Puncture

Background: Postdural puncture headache (PDPH) occurs in up to 80% of parturients who experience inadvertent dural puncture during epidural catheter placement. The authors performed a randomized double blind study to assess the effect of prophylactic epidural blood patch on the incidence of PDPH and the need for therapeutic epidural blood patch.

Methods: Sixty-four parturients who incurred inadvertent dural puncture were randomized to receive a prophylactic epidural blood patch with 20 ml autologous blood (prophylactic epidural blood patch group) or a sham patch (sham group). Subjects were evaluated daily for development of PDPH for a minimum of 5 days after dural puncture. Those who developed a PDPH were followed daily for a minimum of 3 days after resolution of the headache. Subjects with moderate headaches who reported difficulties performing childcare activities and all those with severe headaches were advised to receive a therapeutic epidural blood patch.

Results: Eighteen of 32 subjects in each group (56%) developed PDPH. Therapeutic blood patch was recommended in similar numbers of patients in each group. The groups had similar onset time of PDPH, median peak pain scores, and number of days spent unable to perform childcare activities as a result of postural headache. The median duration of PDPH, however, was shorter in the prophylactic epidural blood patch group.     

Headache after spinal anesthesia for cesarean section: a comparison of the 27-gauge Quincke and 24-gauge Sprotte needles.

A high incidence of postdural puncture headache (PDPH) occurs after spinal anesthesia for cesarean section. To examine this problem, a study was conducted with the recently developed 24-gauge Sprotte and 27-gauge Quincke needles in patients undergoing elective and emergency cesarean section (n = 298). The needle to be used was assigned in a random manner: group I, 27-gauge Quincke (n = 147); group II, 24-gauge Sprotte (n = 151). During the postoperative period, patients were visited daily and asked specifically about the presence and severity of headache. The overall incidence of PDPH was 2% (n = 6), five in the Quincke group (3.5%) and one in the Sprotte group (0.7%). There was no significant difference in the incidence of PDPH between the two groups. Five headaches were classified as mild, and only one was moderate to severe. All headaches resolved quickly with conservative management and without blood patch. The authors conclude that the choice between a 27-gauge Quincke and a 24-gauge Sprotte needle does not influence the incidence of PDPH after spinal anesthesia for cesarean section.     

Post dural puncture headache in obstetric patients: experience from a West African teaching hospital

BACKGROUND: This prospective, non-randomised study examined the frequency and severity of post dural puncture headache in 96 Ghanaian women who consented to spinal anaesthesia for caesarean section at the Korle Bu Teaching Hospital, Accra, Ghana. METHOD: Spinal anaesthesia was performed using 22-gauge (n = 22), 25-gauge (n = 46) or 26-gauge (n = 38) Quincke needles. Patients were followed up to determine the incidence and severity of post spinal headache. RESULT: The overall incidence of post dural puncture headache was 8.3%, but was significantly higher (33%) in patients in whom 22-gauge Quincke needles were used than in the other two groups (4% and 5% respectively: P = 0.003). Most patients rated their headache as mild to moderate on a 10-cm visual analogue scale. CONCLUSIONS: In view of the high incidence of headache and the need for treatment associated with the use of the 22-gauge Quincke needle, we recommend that this should not be used in the obstetric population. We are also aware that the incidence of post dural puncture headache could be further reduced by the use of small calibre pencil-point needles but these are currently very expensive and many obstetric units in developing countries may not be able to afford them.     

Post-dural puncture headache in the parturient

Post-dural puncture headache (PDPH) is one of the most common and debilitating complications of neuraxial blockade in the parturient. The obstetric population is at particular risk with up to 80% of women developing symptoms after inadvertent dural puncture during epidural insertion. PDPH typically develops 24–48 hours post-puncture and is classically described as an occipito-frontal headache with postural features. Diagnosis and assessment should include consideration of other potential causes of post-partum headache. At the time of inadvertent dural puncture (IDP) one may insert an intrathecal catheter, re-site the epidural or use alternative analgesia. Initial treatment of a PDPH includes bed rest, adequate hydration and simple analgesics. Epidural blood patch (EBP) remains the gold standard treatment of PDPH.     

Fluoroscopically guided epidural blood patch in patients with postdural puncture headache after spinal and epidural anesthesia

Postdural puncture headache (PDPH) is one of the major complications after spinal and epidural anesthesia. An epidural blood patch (EBP) may be applied when PDPH persists regardless of conservative treatment. We describe the results of management including fluoroscopically guided EBP in a series of patients with moderate to severe PDPH. From January 2007 to December 2009, PDPH developed in 15 of 3,381 patients (0.44%) who received epidural or spinal anesthesia: 5 (0.21%) after general anesthesia combined with epidural anesthesia, 8 (0.81%) after spinal anesthesia, and 2 (3.14%) after combined spinal and epidural anesthesia. Of 15 patients, PDPH was relieved without the EBP in 9 patients and 6 patients required the EBP. EBP was performed under fluoroscopy in a prone position; a 4:1 mixture of autologous blood and contrast medium was injected to cover the site of dural puncture. The success rate of fluoroscopically guided EBP was 100% with a mean blood volume of 7.2 ml. No complications were associated with EBP except for a mild backache. Fluoroscopically guided EBP may be successfully and safely performed to treat persistent PDPH with a relatively small volume of blood for epidural injection.     

Decreased incidence of headache after unintentional dural puncture in patients with cesarean delivery administered with postoperative epidural analgesia

Purpose  To investigate how subsequent placement of a catheter into the epidural space after unintentional dural puncture for postoperative analgesia for 36–72 h affected the incidence of post-dural puncture headache (PDPH). Methods  The records of 52 parturients who had had accidental dural puncture in cesarean delivery were reviewed. The parturients were assigned to two groups. Twenty-eight parturients were assigned to the study group, in whom an epidural catheter was inserted and was used for anesthesia and postoperative analgesia. Twenty-four parturients were assigned to the control group, in whom spinal anesthesia (n = 20) or general anesthesia (n = 4) was applied. For postoperative analgesia in patients with incision pain above visual analog scale (VAS) 3, 3 mg morphine in 15 ml saline was administered through the epidural catheter in the study group, while intramuscular meperidine or tramadol was administered in the control group. Once PDPH was observed, conservative treatment was tried first. If the headache persisted despite conservative treatment, an epidural blood patch was applied through the catheter or a reinserted epidural needle. Results  The study group demonstrated significant reduction of the incidence of PDPH and reduction in the indication for an epidural blood patch compared to the control group (7.1% vs 58% [P = 0.000] and 3.6% vs 37.5% [P = 0.002], respectively). Conclusion  Subsequent catheter placement into the epidural space after unintentional dural puncture in cesarean delivery and leaving the catheter for postoperative analgesia for 36–72 h may reduce the incidence of PDPH.     

Postpartum cerebral venous sinus thrombosis following obstetric neuraxial blockade: a literature review with analysis of 58 case reports

BackgroundCerebral venous sinus thrombosis (CVST) is a rare complication of pregnancy. It usually presents with a headache and may mimic a post-dural puncture headache (PDPH) in women who receive a neuraxial block.MethodsMedline, CINAHL and EMBASE databases were searched to identify postpartum cases of CVST following neuraxial block. The aim was to delineate the characteristics, presentation, investigations, and outcomes of postpartum women who presented with CVST.ResultsForty-nine articles with 58 case reports were identified. Forty-two women (72.4%) had an epidural attempted whilst 16 women (27.6%) received a spinal anaesthetic. Accidental dural puncture (ADP) was reported in 17 women (40.5%). Headache was the presenting symptom in 57 women (98.3%); 26 women (44.8%) also experienced seizures. Post-dural puncture headache was reported in 46 (79.3%) and an epidural blood patch was performed in 26 women (44.8%). Superior sagittal sinus, transverse sinus, and cortical veins were the most common sites of thrombosis. The median time to diagnosis was 6.5 days from delivery. Magnetic resonance imaging was the most common diagnostic neuro-imaging modality. Full neurological recovery was reported in 48 (82.8%), whilst neurological deficits were reported in six (10.3%) women.DiscussionThe diagnosis of CVST may be overlooked in women who present with headache following neuraxial block. A change in character of headache with loss of postural element, and focal neurological signs are the key clinical features that could help anaesthetists differentiate headache of CVST from PDPH. The high reported rates of ADP and PDPH lend support to their possible association with CVST.     

Post-dural puncture headache in the parturient

Post-dural puncture headache (PDPH) is a common and debilitating complication of central neuraxial blockade in the parturient. The obstetric population is at particular risk with up to 80% of women developing symptoms after accidental dural puncture (ADP) during labour epidural insertion. PDPH typically develops 24–48 hours post puncture and is classically described as an occipito-frontal headache with postural features. Diagnosis and assessment should include consideration of other potential causes of post-partum headache. Initial treatment of PDPH includes adequate hydration and analgesics. Epidural blood patch (EBP) remains the gold standard treatment. It is more successful if performed over 24–48 hours after the development of symptoms. Complete and permanent relief of symptoms following a single EBP occurs in up to one third of cases where headache follows ADP with an epidural needle. Complete or partial relief may be seen in 50–80% overall. Higher success rates are achieved following a second EBP. There is now UK national guidance on the treatment of post dural puncture headache published by the Obstetric Anaesthetists Association (OAA).     

Grading of severity of postdural puncture headache after 27-gauge Quincke and Whitacre needles

Background: Small-gauge needles are reported to have a low incidence of complications. Pencil-point needles are associated with a lower frequency of postdural puncture headache (PDPH), but a higher failure rate than Quincke needles.
Methods: The incidence of PDPH was investigated in 200 patients under the age of 45, undergoing day-care surgery, after spinal anaesthesia with either 27-gauge Quincke or Whitacre needle. The severity of headache was graded as I (mild), II (moderate) or III (severe) using a grading system based on the visual analogue scale (VAS) associated with a functional rating (FG).
Results: The frequency of PDPH following the Whitacre needle was 0% and 5.6% after the Quincke needle ( P = 0.05). Two PDPHs were assessed as grade III, and three as grade II. All PDPHs occurred when the Quincke needle bevel was withdrawn perpendicular to the dural fibres following parallel insertion. No PDPH occurred when the bevel was inserted and removed parallel to the dural fibres ( P < 0.05). There was no statistical difference ( P >0.8) in the incidence of PDPH and postdural puncture-related headaches (PDPR-H) in patients with recurrent headaches or migraine compared to patients with no previous history of headaches.
Conclusions: We conclude that the 27-gauge Whitacre needle is the 'needle of choice' in patients with normal body stature. The incidence of PDPH following Quincke needles may not only be affected by the direction of the bevel during insertion but also during removal. Statistically, there was no gender variation in PDPH in this study (P=0.5). A previous history of recurrent headache or migraine does not predispose to PDPH.     

Accidental dural puncture,postdural puncture headache,intrathecal catheters,and epidural blood patch: revisiting the old nemesis

One of the controversial management options for accidental dural puncture in pregnant patients is the conversion of labor epidural analgesia to continuous spinal analgesia by threading the epidural catheter intrathecally. No clear consensus exists on how to best prevent severe headache from occurring after accidental dural puncture. To investigate whether the intrathecal placement of an epidural catheter following accidental dural puncture impacts the incidence of postdural puncture headache (PDPH) and the subsequent need for an epidural blood patch in parturients. A retrospective chart review of accidental dural puncture was performed at Hutzel Women’s Hospital in Detroit, MI, USA for the years 2002–2010. Documented cases of accidental dural punctures (N = 238) were distributed into two groups based on their management: an intrathecal catheter (ITC) group in which the epidural catheter was inserted intrathecally and a non-intrathecal catheter (non-ITC) group that received the epidural catheter inserted at different levels of lumbar interspaces. The incidence of PDPH as well as the necessity for epidural blood patch was analyzed using two-tailed Fisher’s exact test. In the non-ITC group, 99 (54 %) parturients developed PDPH in comparison to 20 (37 %) in the ITC [odds ratio (OR), 1.98; 95 % confidence interval (CI), 1.06–3.69; P = 0.03]. Fifty-seven (31 %) of 182 patients in the non-ITC group required an epidural blood patch (EBP) (data for 2 patients of 184 were missing). In contrast, 7 (13 %) of parturients in the ITC group required an EBP. The incidence of EBP was calculated in parturients who actually developed headache to be 57 of 99 (57 %) in the non-ITC group versus 7 of 20 (35 %) in the ITC group (OR, 2.52; 95 % CI, 0.92–6.68; P = 0.07). The insertion of an intrathecal catheter following accidental dural puncture decreases the incidence of PDPH but not the need for epidural blood patch in parturients.     

Superior sagittal sinus thrombosis in a patient with postdural puncture headache

BACKGROUND AND OBJECTIVES: The occurrence of concomitant intracranial pathology in a patient with postdural puncture headache (PDPH) is rare. We present a patient who had a superior sagittal sinus thrombosis in addition to his PDPH. The signs and symptoms of intracranial pathology in patients with dural puncture headache, in addition to their postural headache, are discussed. CASE REPORT: A 32-year-old man with lymphoblastic lymphoma received treatment with daunorubicin, vincristine, and prednisone. He developed postural headache and severe nausea and vomiting after a diagnostic lumbar puncture. Magnetic resonance imaging (MRI) showed superior sagittal sinus (SSS) thrombosis and meningeal enhancement. An epidural blood patch was performed and enoxaparin was prescribed for 6 months. He has remained asymptomatic. CONCLUSIONS: Patients with PDPH have classic postural headache. The occurrence of additional signs and symptoms should alert the clinician to the presence of intracranial pathology. Patients with lymphoblastic lymphoma who had treatment with L-asparaginase and steroid are predisposed to the development of cortical venous thrombosis and may have this syndrome in addition to a dural puncture headache.     

The PENCAN 25-gauge needle: A new pencil-point needle for spinal anesthesia tested in 1,193 patients

Background and Objectives. The PENCAN 25-gauge spinal needle is a new pencil-point needle with an inner diameter of 0.32 mm resulting in a relatively high cerebrospinal fluid (CSF) flow. The PENCAN 25-gauge needle was tested for ease of identification of a successful dural puncture, the failure rate of spinal anesthesia, and the incidence of postdural puncture headache (PDPH). Methods. In a multicenter trial, the needle was tested in patients undergoing spinal anesthesia. A questionnaire evaluated the characteristics of the dural puncture. A second questionnaire was used to assess postspinal side effects (PDPH, atypical headache, audiovisual disturbances). Results. In 1,193 patients, dural puncture was evaluated as easy in 85.2%, as moderate in 6.2%, as difficult in 6.7%, and as impossible in 1.9%. Needle performance was assessed as excellent or satisfactory in 96.9%. In 95.9% of patients, CSF appeared within 2 seconds. A perceptible “click” was noticed in 78.4% of patients. In 1.9%, CSF could not be obtained, because of spine deformities, obesity, or bending of the needle. In 1,166 patients, postpuncture complaints were evaluated, involving 635 women (54.5%), 773 patients (66.3%) under the age of 50 years old, and 170 (14.6%) cesarean deliveries. The overall incidence of PDPH was 1.3% (n = 15). A bloodpatch was needed in five patients. After cesarean delivery the incidence of PDPH was 3.4%, all responding to conservative treatment. Atypical headache and isolated audiovisual disturbances occurred in 7.5% and 1.5% of patients, respectively. Conclusions. A failure rate of 1.9% together with a 1.3% incidence of PDPH were comparable to other 25-gauge pencil-point needles. The rapid appearance of CSF and a perceptible “click” made prompt recognition of successful dural puncture possible.     

The epidural blood patch. Resolving the controversies

PURPOSE: To review the literature regarding epidural blood patch (EBP) to generate conclusions relating to the controversial issues surrounding its application. SOURCE: A Medline search was made for relevant publications using keywords epidural blood patch, prophylactic epidural blood patch, dural puncture, and postdural puncture headache. Bibliographies of retrieved articles were hand-searched for relevant articles. Case series and comparative trials were emphasized in the analyses. These were culled and those deemed relevant were reviewed. PRINCIPAL FINDINGS: The majority of the literature consists of observational reports: there are few comparative studies. Headache most likely results from cerebrospinal fluid (CSF) loss leading to intracranial content shift and traction on pain sensitive structures; cerebrovascular alterations may be implicated. An EBP with 10-15 ml blood is indicated and effective therapy for severe headache after dural puncture. There is conflicting evidence regarding larger volume blood injections or delaying EBP for 24 hr or more after the diagnosis of postdural puncture headache (PDPH). Efficacy of EBP is related to a "patch effect" as well as transmission of increased epidural space pressure to the CSF space. Previous estimates of EBP efficacy were overgenerous; persistent symptomatic relief can be expected in 61-75% of patients with initial EBP. Patching with non-blood solutions, although initially effective, is associated with a high incidence of headache recurrence. Prophylactic injection of saline or blood decreases the incidence of severe headache after dural puncture. CONCLUSION: Blood-patching is an effective treatment of PDPH but further research is required regarding its mechanisms and prophylaxis.     

Repetitive hearing loss following dural puncture treated with autologous epidural blood patch

A case of repetitive hearing loss following an otherwise uncomplicated diagnostic dural puncture is presented. The patient developed severe postdural puncture headache (PDPH) and three episodes of pronounced vestibulocochlear disturbances within five weeks after only one dural puncture. On all three occasions the headache and the associated symptoms were treated with an autologous epidural blood patch (AEBP) resulting in the immediate disappearance of all the subjective complaints of postdural puncture headache and the normalization of an audiological test within minutes.     

Epidural blood patch for management of postdural puncture headache in adolescents

BACKGROUND: In some patients spinal puncture (SP) is followed by postdural puncture headache (PDPH). When the symptoms of PDPH are severe and are not relieved within a few days an epidural blood patch (EBP) might be performed. The aim of this survey was to review requests for EBPs and to evaluate the effectiveness of EBP in patients aged 13-18 years during a 6.5 year period ending in June 2001. METHODS: The Information System Patient Measures Database was interrogated to identify patients who were referred for EBP. After identification, the patients' medical records were reviewed in detail for the characteristics of PDPH and other symptoms, and for the effectiveness of the EBP. RESULTS: Forty-two EBPs were performed after 40 SPs on 37 patients (24 girls, 13 boys). Epidural blood patches were performed twice in five patients. The reasons for repeating the procedure were repeat SP with new PDPH in three patients and an unsatisfactory effect in two patients. Twenty-eight of the 40 spinal punctures (70%) had been performed for diagnostic use and 10 (25%) for spinal anesthesia. Two patients (5%) developed PDPH after inadvertent dural puncture with an epidural needle. In 37 cases the criteria for PDPH were fulfilled, and one patient had a cerebrospinal fluid fistula headache. Two-thirds of the girls had associated symptoms of headache compared with one-third of the boys. Epidural blood patch was performed 1-22 days after SP with 0.2 ml/kg (mean) of autologous blood injected into the epidural space. The success rate of the first injection was 37 out of 40 EBP (93%), and the second injection was effective in both patients with recurred PDPH. CONCLUSION: Epidural blood patch seems to be an effective and safe procedure in adolescents for treating severe and persistent PDPH.     

Decreased incidence of headache after accidental dural puncture in caesarean delivery patients receiving continuous postoperative intrathecal analgesia

To examine the effects of prolonged (> 24 h) intrathecal catheterization with the use of postoperative analgesia on the incidence of post–dural puncture headache (PDPH), charts of 45 obstetric patients who had accidental dural puncture following attempts at epidural block were reviewed retrospectively. Three groups were identified: Group I (n = 15) patients had a dural puncture on the first attempt at epidural block, but successful epidural block on a repeated attempt; Group II (n=17) patients had a dural puncture with immediate conversion to continuous spinal anaesthesia with catheterization lasting only for the duration of caesarean delivery; Group III (n= 13) patients had an immediate conversion to spinal anaesthesia and received post–caesarean section continuous intrathecal patient–controlled analgesia consisting of fentanyl 5 (ig'ml^-1 with bupivacaine 0.25 mg·ml^-1 and epinephrine 2 μg·ml^-1 with catheterization lasting >24 h. No parturient in group III developed a PDPH. This was substantially lower ( P < 0.009) than the 33% incidence for group I and the 47% incidence for group II. The incidence of a PDPH did not differ between group I and II. Similarly, there was no difference between group I and II with regard to requests for a blood patch. Patients receiving continuous intrathecal analgesia had excellent pain relief, could easily ambulate and none complained of pruritus, nausea, vomiting, sensory loss or weakness. In conclusion, indwelling spinal catheterization > 24 h with continuous intrathecal analgesia following accidental dural puncture in parturients may for some patients be a suitable method for providing PDPH prophylaxis and postoperative analgesia.     

Treatment of post-dural-puncture headache with intravenous cortisone

Postdural puncture headache (PDPH) is the most frequent complication of procedures involving dural penetration for spinal anesthesia or following unintentional dural puncture during attempted epidural anesthesia or analgesia. PDPH causes serious problems for women who have just given birth, as they are unable to give adequate care to their infants. The causes of PDPH are poorly understood and treatments are therefore various and symptomatic; most are empirical and not all are effective. When conservative measures fail, an alternative that may be proposed is the blood patch, an invasive technique which is not without risk and which many patients reject. We report three cases of incapacitating PDPH in women after vaginal or caesarian delivery in which symptoms resolved with intravenous hydrocortisone treatment. Hydrocortisone treatment for PDPH has never been reported in the literature, but given our results, we consider that clinical trials are warranted to establish the efficacy of this treatment and to determine if there is a chance that it might offer an alternative to the blood patch.     

Second stage pushing correlates with headache after unintentional dural puncture in parturients

PURPOSE: To determine the association between bearing down, postdural puncture headache (PDPH) and epidural blood patch (EBP) following single 17 gauge unintentional dural puncture (UDP) in parturients. METHODS: The charts of 60 parturients identified with UDP in our institutional database during epidural placement were independently reviewed. Patients were divided into categories based on the anesthetic record: well-documented single punctures; well-documented multiple punctures; catheter-related puncture; unclear category (not clear if more than one puncture occurred or if dural puncture had occurred at all) and no evidence of dural puncture. Patients with single 17 gauge punctures were divided into those who had pushed (Group 1) and those who had not (Group 2). Group 2 patients had undergone Cesarean section before reaching second stage labour. The incidence of PDPH, EBP, and cumulative duration to delivery after UDP were compared between groups. RESULTS: Thirty-three patients with well-documented single punctures were identified: 23 had engaged in active pushing as part of second stage labour (Group 1); 10 had not (Group 2). Seventy-four percent of Group1I developed PDPH compared with 10% in Group 2 (P < 0.002). Fifty-seven percent of Group 1 received an EBP compared with 0% in Group 2 (P < 0.002). Increasing the duration of pushing was associated with an increasing incidence of PDPH; the majority of women who pushed > 30 min developed headache. CONCLUSIONS: An increased incidence of PDPH and EBP after UDP occurs in women bearing down in 2nd stage labour when compared with those who never pushed. There was also an association between the cumulative duration of bearing down and the incidence of PDPH.     

Postdural puncture headache after spinal anaesthesia in young orthopaedic outpatients using 27-g needles

PURPOSE: Two large studies reported a very low rate (0.5-1.8%) of postdural puncture headache (PDPH) with the use of 27-G spinal needles. We suspected that it might be higher in young ambulatory patients. The purpose of this study was to establish the rate prospectively in such a patient population using two types of needles. METHODS: Two hundred male and female, outpatients, 18-45 yr, undergoing knee arthroscopy under spinal anaesthesia were randomly assigned to receive spinal anaesthesia with hyperbaric lidocaine 5% using either a Quincke or a Whitacre 27-G needle. Twenty patients choosing general anaesthesia formed a comparative group. Using a previously validated questionnaire, the incidence and nature of PDPH were evaluated by telephone three to five days after surgery by an anaesthetist unaware of the anaesthetic technique used. Once all data were collected, an anaesthetist not involved in the study determined in a blinded fashion which headaches were likely to be PDPH. Grading and classification of headaches were based on several criteria: postural nature, duration, intensity and confinement to bed. RESULTS: The overall incidence of PDPH in both spinal groups was 9.3%. The incidence in women, 20.4%, was higher than in men, 5.5%, (P < 0.05). Only one patient required a blood patch. Both types of needle were comparable with respect to the incidence, severity and duration of PDPH, number of dural punctures and failed spinal blocks. CONCLUSION: The rate of PDPH was higher than in large published studies with 27-G Quincke and Whitacre needles and greater in women than in men.