Nerve Stimulator-Guided Occipital Nerve Blockade for Postdural Puncture Headache

Evidence-based clinical practice guidelines on postdural puncture headache: a consensus report from a multisociety international working group

INTRODUCTION

Postdural puncture headache (PDPH) can follow unintentional dural puncture during epidural techniques or intentional dural puncture during neuraxial procedures such as a lumbar puncture or spinal anesthesia. Evidence-based guidance on the prevention, diagnosis or management of this condition is, however, currently lacking. This multisociety guidance aims to fill this void and provide practitioners with comprehensive information and patient-centric recommendations to prevent, diagnose and manage patients with PDPH.

METHODS

Based on input from committee members and stakeholders, the committee cochairs developed 10 review questions deemed important for the prevention, diagnosis and management of PDPH. A literature search for each question was performed in MEDLINE (Ovid) on 2 March 2022. The results from each search were imported into separate Covidence projects for deduplication and screening, followed by data extraction. Additional relevant clinical trials, systematic reviews and research studies published through March 2022 were also considered for the development of guidelines and shared with contributors. Each group submitted a structured narrative review along with recommendations graded according to the US Preventative Services Task Force grading of evidence. The interim draft was shared electronically, with each collaborator requested to vote anonymously on each recommendation using two rounds of a modified Delphi approach.

RESULTS

Based on contemporary evidence and consensus, the multidisciplinary panel generated 50 recommendations to provide guidance regarding risk factors, prevention, diagnosis and management of PDPH, along with their strength and certainty of evidence. After two rounds of voting, we achieved a high level of consensus for all statements and recommendations. Several recommendations had moderate-to-low certainty of evidence.

CONCLUSIONS

These clinical practice guidelines for PDPH provide a framework to improve identification, evaluation and delivery of evidence-based care by physicians performing neuraxial procedures to improve the quality of care and align with patients' interests. Uncertainty remains regarding best practice for the majority of management approaches for PDPH due to the paucity of evidence. Additionally, opportunities for future research are identified.

Therapeutic Use of Low-Dose Local Anesthetics in Pain, Inflammation, and Other Clinical Conditions: A Systematic Scoping Review

The use of low-dose local anesthetics (LAs) has significantly transformed patient care by providing rapid and effective relief of pain and other clinical conditions while minimizing recovery time. This study aims to identify and describe the existing scientific evidence on the therapeutic use of low-dose LAs in various conditions and to identify gaps in the current literature in order to prioritize future research. This systematic scoping review adhered to the methodological guidelines outlined in the Arksey and O'Malley framework, which includes five distinct stages. Of the 129 studies included, 37.98% (n = 49) were clinical trials, 55.03% (n = 71) were observational studies, and 6.97% (n = 9) were systematic reviews. The most commonly reported indication for the use of low-dose LAs was chronic pain management (72.86%), followed by acute pain management (13.17%). Additionally, non-pain-related indications were also identified (13.95%). Overall, the administration of low-dose, short-acting LAs demonstrated favorable outcomes in terms of pain management and reduction in anxiety and depression scales, thereby having a positive impact on the patients' quality of life. This review represents the first systematic scoping review regarding the therapeutic role of LAs. To substantiate the reported positive effects on efficacy and safety, further rigorous research comprising larger, well-designed randomized controlled trials (RCTs) and long-term outcome monitoring is imperative.

Greater occipital nerve block in the treatment of headaches. Review of evidence

INTRODUCTION

Peripheral nerve blocks have been a common treatment for multiple headaches. By far, the greater occipital nerve block is the most used and with the stronger body of evidence in routine clinical practice.

METHODS

We searched Pubmed Meta-Analysis/Systematic Review, in the last 10 years. Of these results, meta-analyses, and in the absence of these systematic reviews, assessing Greater Occipital Nerve Block in headache has been selected for review.

RESULTS

We identified 95 studies in Pubmed, 13 that met the inclusion criteria.

CONCLUSION

Greater occipital block is an effective and safe technique, easy to perform and which has shown its usefulness in migraine, cluster headache, cervicogenic headache and Post-dural puncture headache. However, more studies are needed to clarify its long-term efficacy, its place in clinical treatment, the possible difference between different anaesthetics, the most convenient dosage and the role of concomitant use of corticosteroids.

Efficacy of greater occipital nerve block for pain relief in patients with postdural puncture headache: A meta-analysis

BACKGROUND

This study aimed at assessing the therapeutic effectiveness of greater occipital nerve block (GONB) against postdural puncture headache (PDPH).

METHODS

Studies investigating analgesic effects of GONB against PDPH in adults were retrieved from the MEDLINE, EMBASE, Google scholar, and Cochrane central databases from their inception dates to May, 2021. Pain score at postprocedural 24 hours was the primary endpoint, while secondary endpoints were pain score at postprocedural 1 hour and 12 hours as well as the risk of intervention failure.

RESULTS

Of the 7 studies (randomized controlled trials [RCTs], n = 4; non-RCTs, n = 3) that recruited 275 patients, 2 investigated female patients undergoing cesarean section and the other 5 were conducted in both obstetric and nonobstetric settings. Pooled results showed a lower mean pain score at 24 hours (i.e., primary outcome) (mean difference [MD] = -2.66, 95%: CI: -3.98 to -1.33, P < .001; I2 = 97%, 6 studies), 1 hour (MD = -4.23, 95% confidence interval [CI]: -5.08 to -3.37, P < .00001; I2 = 86%, 5 studies), and 6 hours (MD = -2.78, 95% CI: -4.99 to -0.57, P = .01; I2 = 98%, 4 studies) in patients with GONB compared to those without. Trial sequential analysis supported the robustness of evidence at postprocedural 24 hours. The use of GONB also decreased the risk of intervention failure (relative ratio [RR] = 0.4, 95% CI: 0.19 to 0.82, P = .01; I2 = 96%, 6 studies, 277 patients).

CONCLUSION

Our results suggested a therapeutic effect of greater occipital nerve block against postdural puncture headache up to postprocedural 24 hours. Further large-scale studies are warranted to evaluate its therapeutic benefit beyond the acute stage.

Correlates of post-dural puncture headache and efficacy of different treatment options: a monocentric retrospective study

Background:

Post-dural puncture headache (PDPH) is a severe positional headache that appears usually within 72 hours after inadvertent dural puncture, secondary to cerebrospinal fluid leakage. It is treated first by conservative treatment (including bed rest, hydration, caffeine and simple analgesia) and then by invasive procedures such as blood patch. This study aims to evaluate factors associated with PDPH among a sample of Lebanese patients and assess the rate of success of different treatment modalities administered in a specific sequence: conservative treatment first, then ultrasound-guided bilateral greater occipital nerve block (GONB) if failure of conservative treatment and finally epidural blood patch (EBP) if failure of GONB.

Methods:

A retrospective case–control study was conducted between January 2015 and December 2019 in the Notre-Dame des Secours University Hospital. Out of a total of 10,051 procedures, 18 cases were diagnosed with PDPH and were matched based on gender, age and procedure type to a control group of patients who did not develop PDPH randomly selected (72 patients).

Results:

Higher body mass index (adjusted odds ratio (ORa) = 0.77) was significantly associated with lower odds of PDPH, whereas the presence of previous chronic headache (ORa = 5.56) was significantly associated with higher odds of PDPH. Seven out of 18 (38.89%) had their pain symptoms/headache resolved on conservative treatment. Out of the remaining 11 patients, 6 (33.33%) had their symptoms resolved on GONB with a significant decrease in the pain score 48 hours after GONB compared to baseline (5.55 vs 9.73; p = 0.007). Five patients (27.78%) had their symptoms resolved using a blood patch, with a significant decrease in the pain score after blood patch compared to baseline (3.00 vs 9.80; p = 0.041).

Conclusion:

Our preliminary data suggest that ultrasound-guided GONB is a minimally risky and efficacious technique for those who fail to respond to conservative treatment.

Postdural puncture headache as a complication of lumbar puncture: clinical manifestations, pathophysiology, and treatment

OBJECTIVE

This manuscript is a narrative review of peer-reviewed studies of postdural puncture headache (PDPH) as the most common complication of a diagnostic and therapeutic lumbar puncture (LP) and LP due to the damage of the dura mater in epidural anesthesia.

METHODS

Author searched articles related to the PDPH and its risk factors, pathophysiology diagnosis, differential diagnosis, and therapy. All studies according to the analyzed parameters and their relevance to the clinical practice, as well as quality of the study methods, were selected for further analysis.

RESULTS

The review presents the clinical and paraclinical prediction criteria for the onset, clinical features, course, and efficiency of specific therapeutic interventions which are of a particular clinical benefit for the prevention, pathogenetic treatment, and differential diagnosis of PDPH. The analysis of prediction parameters for the onset, clinical course, and associated symptoms and signs of PDPH is a contribution to the understanding of pathophysiology of intracranial hypotension, since PDPH can be considered a clinical model of intracranial hypotension.

CONCLUSIONS

Given that LP is a common procedure in clinical practice, it is necessary to have a comprehensive knowledge of the risk factors, pathophysiological, diagnostic, differentially diagnostic, and therapeutic aspects of PDPH.

Relief of Secondary Headaches with High Thoracic Erector Spinae Plane Block

Intractable headaches can be debilitating, often leading to significant distress, prolonged medical treatment, and unanticipated hospital admissions. There have been significant advances in the treatment of primary intractable headaches such as migraines, tension headaches, and cluster headaches beyond medical management. Treatments may now include interventional strategies such as trigger-point injections, peripheral nerve stimulators, or peripheral nerve and ganglion blocks. There are few studies, however, describing the use of interventional techniques for the management of intractable secondary headaches, including those attributed to injury or infection. A new regional anesthetic technique, the erector spinae plane (ESP) block, was initially used for neuropathic thoracic pain. ESP block has since been reported to provide acute and chronic pain relief of the shoulder, spine, abdomen, pelvis, thorax, and lower extremity. Additionally, there has been one case report to describe the use of the ESP block in the treatment of refractory tension headache. We report four cases of effective analgesia for intractable secondary headache resistant to medical management with high thoracic ESP blocks. In each case, the ESP block provided instant pain relief. We suggest that the findings of this case series indicate that the ESP block may be a useful intervention in patients with severe secondary headache or posterior cervical pain where conventional therapies have limited success, though more studies are necessary.

Suboccipital Muscles Injection for Management of Post-Dural Puncture Headache After Cesarean Delivery: A Randomized-Controlled Trial

INTRODUCTION:

Post-dural puncture headache (PDPH) is a common complication following neuraxial anaesthesia that increases the duration of hospital stay.

AIM:

This study aims to evaluate the effectiveness of injection of the dexamethasone-lidocaine mixture in suboccipital muscles treatment of PDPH after cesarean section.

PATIENT AND METHODS:

A group of 90 females with PDPH following cesarean section under spinal anaesthesia were randomly allocated into two equal groups: study group (Group S) and control group (group C). All patients received bilateral intramuscular (in the suboccipital muscle) (Group S) (n = 45) patients received lidocaine 40 mg (2 mL of 2% solution) and dexamethasone 8mg in a total volume of 4 mL; whilst, patients in the control group (group C) (n = 45) received 4 mL normal saline. The primary outcome is the Visual Analogue Score for a headache at 24 hours after injection.

RESULTS:

Demographic data and the baseline, headache score, neck muscle spasm, and nausea were comparable in both groups. Group S showed lower headache score compared to group C at all the post-injection time points. All patients in group S showed resolution of nausea after the intervention; while none of the control group showed any improvement. All patients of group C needed rescue analgesia; while only 6 (13.3%) patients in group S asked for an analgesic. Time to the first analgesic request was longer in group S compared to group C (10.17 ± 7.96 hours versus 1.00 ± 0.00 hours, P < 0.001).

CONCLUSION:

Ultrasound-guided injection of the dexamethasone-lidocaine mixture in suboccipital muscles is effective management of PDPH after CS.

Efficacy of bilateral greater occipital nerve block in postdural puncture headache: a narrative review

The Epidural blood patch is considered the gold standard for managing postdural puncture headache when supportive measures fail. However, it is a procedure which can lead to another inadvertent dural puncture. Other potential adverse events that could occur during a blood patch are meningitis, neurological deficits, and unconsciousness. The bilateral greater occipital nerve block has been used for treating chronic headaches in patients with PDPH with a single injection. This minimally invasive, simple procedure can be considered for patients early, along with other supportive treatment, and an epidural blood patch can be avoided.

Ultrasound-Guided Bilateral Greater Occipital Nerve Block for Mass Excision

Anaesthesiologists must always prefer the safest method to minimize the risk for patients. At present, ultrasound-guided blockage of the greater occipital nerve can be performed in a safe manner. In this report, we presented our experience of ultrasound-guided blockage of the greater occipital nerve that we performed in a patient with a mass at the back of the neck who had risk of general anaesthesia because of comorbidities.

Bilateral greater occipital nerve block for treatment of post-dural puncture headache after caesarean operations

BACKGROUND

Post-dural puncture headache (PDPH) is an important complication of neuroaxial anesthesia and more frequently noted in pregnant women. The pain is described as severe, disturbing and its location is usually fronto-occipital. The conservative treatment of PDPH consists of bed rest, fluid theraphy, analgesics and caffeine. Epidural blood patch is gold standard theraphy but it is an invasive method. The greater occipital nerve (GON) is formed of sensory fibers that originate in the C2 and C3 segments of the spinal cord and it is the main sensory nerve of the occipital region. GON blockage has been used for the treatment of many kinds of headache. The aim of this retrospective study is to present the results of PDPH treated with GON block over 1 year period in our institute.

METHODS

16 patients who had been diagnosed to have PDPH, and performed GON block after caesarean operations were included in the study. GON blocks were performed as the first treatment directly after diagnose of the PDPH with levobupivacaine and dexamethasone.

RESULTS

The mean VAS score of the patients was 8.75 (±0.93) before the block; 3.87 (±1.78) 10min after the block; 1.18 (±2.04) 2h after the block and 2.13 (±1.64) 24h after the block. No adverse effects were observed.

CONCLUSIONS

Treatment of PDPH with GON block seems to be a minimal invasive, easy and effective method especially after caesarean operations. A GON block may be considered before the application of a blood patch.

Drug therapy for treating post-dural puncture headache

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 8, 2011, on 'Drug therapy for treating post-dural puncture headache'.Post-dural puncture headache (PDPH) is the most common complication of lumbar puncture, an invasive procedure frequently performed in the emergency room. Numerous pharmaceutical drugs have been proposed to treat PDPH but there are still some uncertainties about their clinical effectiveness.

OBJECTIVES

To assess the effectiveness and safety of drugs for treating PDPH in adults and children.

SEARCH METHODS

The searches included the Cochrane Central Register of Controlled Trials (CENTRAL 2014, Issue 6), MEDLINE and MEDLINE in Process (from 1950 to 29 July 2014), EMBASE (from 1980 to 29 July 2014) and CINAHL (from 1982 to July 2014). There were no language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) assessing the effectiveness of any pharmacological drug used for treating PDPH. Outcome measures considered for this review were: PDPH persistence of any severity at follow-up (primary outcome), daily activity limited by headache, conservative supplementary therapeutic option offered, epidural blood patch performed, change in pain severity scores, improvements in pain severity scores, number of days participants stay in hospital, any possible adverse events and missing data.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risk of bias and extracted data. We estimated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous outcomes. We calculated a 95% confidence interval (CI) for each RR and MD. We did not undertake meta-analysis because the included studies assessed different sorts of drugs or different outcomes. We performed an intention-to-treat (ITT) analysis.

MAIN RESULTS

We included 13 small RCTs (479 participants) in this review (at least 274 participants were women, with 118 parturients after a lumbar puncture for regional anaesthesia). In the original version of this Cochrane review, only seven small RCTs (200 participants) were included. Pharmacological drugs assessed were oral and intravenous caffeine, subcutaneous sumatriptan, oral gabapentin, oral pregabalin, oral theophylline, intravenous hydrocortisone, intravenous cosyntropin and intramuscular adrenocorticotropic hormone (ACTH).Two RCTs reported data for PDPH persistence of any severity at follow-up (primary outcome). Caffeine reduced the number of participants with PDPH at one to two hours when compared to placebo. Treatment with caffeine also decreased the need for a conservative supplementary therapeutic option.Treatment with gabapentin resulted in better visual analogue scale (VAS) scores after one, two, three and four days when compared with placebo and also when compared with ergotamine plus caffeine at two, three and four days. Treatment with hydrocortisone plus conventional treatment showed better VAS scores at six, 24 and 48 hours when compared with conventional treatment alone and also when compared with placebo. Treatment with theophylline showed better VAS scores compared with acetaminophen at two, six and 12 hours and also compared with conservative treatment at eight, 16 and 24 hours. Theophylline also showed a lower mean "sum of pain" when compared with placebo. Sumatriptan and ACTH did not show any relevant effect for this outcome.Theophylline resulted in a higher proportion of participants reporting an improvement in pain scores when compared with conservative treatment.There were no clinically significant drug adverse events.The rest of the outcomes were not reported by the included RCTs or did not show any relevant effect.

AUTHORS' CONCLUSIONS

None of the new included studies have provided additional information to change the conclusions of the last published version of the original Cochrane review. Caffeine has shown effectiveness for treating PDPH, decreasing the proportion of participants with PDPH persistence and those requiring supplementary interventions, when compared with placebo. Gabapentin, hydrocortisone and theophylline have been shown to decrease pain severity scores. Theophylline has also been shown to increase the proportion of participants that report an improvement in pain scores when compared with conventional treatment.There is a lack of conclusive evidence for the other drugs assessed (sumatriptan, adrenocorticotropic hormone, pregabalin and cosyntropin).These conclusions should be interpreted with caution, due to the lack of information to allow correct appraisal of risk of bias, the small sample sizes of the studies and also their limited generalisability, as nearly half of the participants were postpartum women in their 30s.

Ultrasound-guided bilateral greater occipital nerve block for the treatment of post-dural puncture headache

Background and Objective:

Post-dural puncture headache (PDPH) is one of the complications frequently observed after spinal or epidural anesthesia with dural penetration. For PDPH patients who do not respond to conservative medical treatment, alternative treatments such as bilateral occipital nerve block should be considered.In this study the efficacy of bilateral occipital nerve block was retrospectively evaluated in patients with post-dural puncture headache.

Methods:

Ultrasound-guided bilateral occipital nerve block was administrated in 21 patients who developed PDPH after spinal anesthesia, but did not respond to conservative medical treatment within 48 hours between January 2012 and February 2014. The study was conducted at Erzincan University Faculty of Medicine Gazi Mengucek Education and Research Hospital

Results:

Mean Visual Analog Scale (VAS) pain scores at 10 minutes and 6, 10, 15 and 24 hours after the block were significantly improved compared to the patients with a pre-block VAS score between 4 and 6 as well as patients with a pre-block VAS score between 7 and 9 (p<0.01). After 24 hours of the block applied, VAS pain score dropped to 1 for all 12 patients who had a pre-block VAS score between 4 and 6. Whereas, VAS score decreased to 2 at 24 hours after the block in only one of the patients with a pre-block VAS between 7 and 9. For the patients with a pre-block VAS score between 7 and 9, there was no significant improvement in the mean VAS score 24 hours after the block.

Conclusions:

For patients with PDPH and a pre-block VAS score between 4 and 6 who do not respond to conservative medical treatment, an ultrasound-guided bilateral occipital nerve block may be effective.

Peripheral nerve blocks in the treatment of migraine in pregnancy

OBJECTIVE

To describe the use of peripheral nerve blocks in a case series of pregnant women with migraine.

METHODS

A retrospective chart review of all pregnant patients treated with peripheral nerve blocks for migraine over a 5-year period was performed. Injections targeted greater occipital, auriculotemporal, supraorbital, and supratrochlear nerves using local anesthetics.

RESULTS

Peripheral nerve blocks were performed 27 times in 13 pregnant women either in a single (n=6) or multiple (n=7) injection series. Mean patient age was 28 years and gestational age was 23.5 weeks, and all women had migraine, including 38.5% who had chronic migraine. Peripheral nerve blocks were performed for status migrainosus (51.8%) or short-term prophylaxis of frequent headache attacks (48.1%). Before peripheral nerve blocks were performed, oral medications failed for all patients and intravenous medications failed for most. In patients with status migrainosus, average pain reduction was 4.0 (±2.6 standard deviation) (P<.001) immediately postprocedure and 4.0 (±4.4 standard deviation) (P=.007) 24 hours postprocedure in comparison to preprocedure pain. For patients receiving peripheral nerve blocks for short-term prophylaxis, immediate mean pain score reduction was 3.0 (±2.1 standard deviation). No patients had any serious immediate, procedurally related adverse events, and the two patients who had no acute pain reduction ultimately developed preeclampsia and had postpartum headache resolution.

CONCLUSION

Peripheral nerve blocks for treatment-refractory migraine may be an effective therapeutic option in pregnancy.

Ultrasound-Guided Bilateral Greater Occipital Nerve Block for the Treatment of Postdural Puncture Headache

Treatment of postdural puncture headaches involves oral or intravenous (IV) fluid or caffeine-containing analgesics, micro-catheterization of spinal space, epidural administration of blood obtained from the patient, or epidural blood patch and fiberoptic imaging-guided epidural interventional techniques. Epidural blood patch is, to date, the most effective treatment, but it is an invasive procedure that may result in serious complications. Spinal anaesthesia was planned for a 22 year old male patient diagnosed with inguinal hernia and for a 42 year old female patient diagnosed with venous stasis. On the first post-operative day, the patients with a postdural puncture headache received conservative medical treatment. As medical treatment was ineffective, they received ultrasound-guided greater bilateral occipital nerve block. In this case report, the effect of the ultrasound-guided bilateral greater occipital nerve block on postdural puncture headache is discussed.

[Post-dural puncture headache]

Headache following dural puncture is a typical complication of neuraxial analgesia and can impair the ability to perform activities of daily living up to incapacitation. The use of thin, atraumatic needles and special puncture techniques (e.g. reinsertion of the stylet) can prevent the majority of post-dural puncture headaches (PDPH). One of the most effective measures to prevent headache after accidental dural puncture is the intrathecal or epidural administration of morphine. When the diagnosis of PDPH is confirmed after excluding relevant differential diagnoses, some of which are potentially life-threatening, caffeine, theophylline and non-opioid analgesics are effective agents to reduce the severity of the symptoms. Traditional measures, such as strict bed rest and hyperhydration can no longer be recommended. If invasive treatment of the headache is warranted an epidural blood patch is still the method of choice with a high rate of success.

[Post-dural puncture headache and blood-patch: theoretical and practical approach]

OBJECTIVE

To review the current research and formulate a rational approach to the physiopathology, cause and treatment of post-dural puncture headache (PDPH).

DATA SOURCES

Articles published to December 2011 were obtained through a search of Medline for the MeSh terms "epidural blood-patch" and "post-dural puncture headache".

STUDY SELECTION

Six hundred and eighty-two pertinent studies were included and 200 were analysed.

DATA SYNTHESIS

Resulting of a dural tap after spinal anaesthesia or diagnostic lumbar puncture or as a complication of epidural anaesthesia, PDPH occurs when an excessive leak of cerebrospinal fluid leads to intracranial hypotension associated to a resultant cerebral vasodilatation. Reduction in cerebrospinal fluid volume in upright position may cause traction of the intracranial structure and stretching of vessels. Typically postural, headache may be associated to nausea, photophobia, tinnitus or arm pain and changes in hearing acuity. In severe cases, there may be cranial nerve dysfunction and nerve palsies secondary to traction on those nerves. The Epidural Blood-Patch (EBP) is considered as the "gold standard" in the treatment of PDHP because it induces a prolonged elevation of subarachnoid and epidural pressures, whereas such elevation is transient with saline or dextran. EBP should be performed within 24-48hours of onset of headache; the optimum volume of epidural blood appears to be 15-20mL. Severe complications following EBP are exceptional. The use of echography may be safety puncture. The optimum timing of epidural blood-patch, the resort of repeating procedure if the symptomatology does not disappear, the alternative to the conventional medical treatment need to be determined by future clinical trial.

Expert consensus recommendations for the performance of peripheral nerve blocks for headaches--a narrative review

OBJECTIVE

To describe a standardized methodology for the performance of peripheral nerve blocks (PNBs) in the treatment of headache disorders.

BACKGROUND

PNBs have long been employed in the management of headache disorders, but a wide variety of techniques are utilized in literature reports and clinical practice.

METHODS

The American Headache Society Special Interest Section for PNBs and other Interventional Procedures convened meetings during 2010-2011 featuring formal discussions and agreements about the procedural details for occipital and trigeminal PNBs. A subcommittee then generated a narrative review detailing the methodology.

RESULTS

PNB indications may include select primary headache disorders, secondary headache disorders, and cranial neuralgias. Special procedural considerations may be necessary in certain patient populations, including pregnancy, the elderly, anesthetic allergy, prior vasovagal attacks, an open skull defect, antiplatelet/anticoagulant use, and cosmetic concerns. PNBs described include greater occipital, lesser occipital, supratrochlear, supraorbital, and auriculotemporal injections. Technical success of the PNB should result in cutaneous anesthesia. Targeted clinical outcomes depend on the indication, and include relief of an acute headache attack, terminating a headache cycle, and transitioning out of a medication-overuse pattern. Reinjection frequency is variable, depending on the indications and agents used, and the addition of corticosteroids may be most appropriate when treating cluster headache.

CONCLUSIONS

These recommendations from the American Headache Society Special Interest Section for PNBs and other Interventional Procedures members for PNB methodology in headache disorder treatment are derived from the available literature and expert consensus. With the exception of cluster headache, there is a paucity of evidence, and further research may result in the revision of these recommendations to improve the outcome and safety of these interventions.

Drug therapy for treating post-dural puncture headache

BACKGROUND

Post-dural puncture headache (PDPH) is the most common complication of lumbar puncture, an invasive procedure frequently performed in the emergency room. Numerous pharmaceutical drugs have been proposed to treat PDPH but there are still some uncertainties about their clinical effectiveness.

OBJECTIVES

To assess the effectiveness and safety of drugs for treating PDPH in adults and children.

SEARCH STRATEGY

The search strategy included the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2011, Issue 2), MEDLINE (from 1950 to June 2011), EMBASE (from 1980 to June 2011) and CINAHL (from 1982 to June 2011). There was no language restriction.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) assessing the effectiveness of any pharmacological drug used for treating PDPH.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risks of bias and extracted data. We estimated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous outcomes. We calculated a 95% confidence interval (CI) for each RR and MD. We did not undertake meta-analysis because the included studies assessed different sorts of drugs or different outcomes. We performed an intention-to-treat (ITT) analysis.

MAIN RESULTS

We included seven RCTs (200 participants) in this review (between 88% and 90.5% were women; mostly parturients (84% to 87%) after a lumbar puncture for a regional anaesthesia). Pharmacological drugs assessed were oral and intravenous caffeine, subcutaneous sumatriptan, oral gabapentin, oral theophylline, intravenous hydrocortisone and intramuscular adrenocorticotropic hormone (ACTH).One RCT reported data about PDPH persistence of any severity at follow up (primary outcome); caffeine reduced the number of participants with PDPH at one to two hours when compared to placebo. Treatment with caffeine also decreased the need for a conservative supplementary therapeutic option. Treatment with gabapentin versus placebo reported better visual analogue scale (VAS) scores after one, two, three and four days; treatment with hydrocortisone plus conventional treatment showed better VAS scores than conventional treatment alone at six, 24 and 48 hours and treatment with theophylline showed a lower mean "sum of pain" when compared with placebo. Sumatriptan and ACTH did not show any relevant effect for this outcome.There were no clinically significant drug adverse events.The rest of the outcomes were not reported by the RCTs or did not show any relevant effect.

AUTHORS' CONCLUSIONS

Caffeine has shown effectiveness for treating PDPH, decreasing the proportion of participants with PDPH persistence and those requiring supplementary interventions, when compared with placebo. Gabapentin, theophylline and hydrocortisone have also shown a decrease in pain severity scores when compared with placebo or conventional care.There is a lack of conclusive evidence for the other drugs assessed (sumatriptan and ACTH).These conclusions should be interpreted with caution, due to the lack of information to allow correct appraisal of risk of bias, the small sample sizes of studies and also the limited generalisability, as most participants were post-partum women in their 30s.

Ultrasonic doppler flowmeter-guided occipital nerve block

BACKGROUND

Greater occipital nerve block is used in the treatment of headaches and neuralgia in the occipital area. We evaluated the efficacy of ultrasonic doppler flowmeter-guided occipital nerve block in patients experiencing headache in the occipital region in a randomized, prospective, placebo-controlled study.

METHODS

Twenty-six patients, aged 18 to 70, with headache in the occipital region, were included in the study. Patients received a greater occipital nerve block performed either under ultrasonic doppler flowmeter guidance using 1% lidocaine or the traditional method. Sensory examination findings in the occipital region were evaluated.

RESULTS

The complete block rate of greater occipital nerve blockade in the doppler group was significantly higher than in the control group respectively (76.9% vs. 30.8%, P < 0.05). Only one patient in the control group had a complication (minimal bleeding).

CONCLUSIONS

Ultrasonic doppler flowmeter-guided occipital nerve block may be a useful method for patients suffering headache in the occipital region.

Peripheral nerve blocks and trigger point injections in headache management - a systematic review and suggestions for future research

Interventional procedures such as peripheral nerve blocks (PNBs) and trigger point injections (TPIs) have long been used in the treatment of various headache disorders. There are, however, little data on their efficacy for the treatment of specific headache syndromes. Moreover, there is no widely accepted agreement among headache specialists as to the optimal technique of injection, type, and doses of the local anesthetics used, and injection regimens. The role of corticosteroids in this setting is also debated. We performed a PubMed search of the literature to find studies on PNBs and TPIs for headache treatment. We classified the abstracted studies based on the procedure performed and the treated condition. We found few controlled studies on the efficacy of PNBs for headaches, and virtually none on the use of TPIs for this indication. The most widely examined procedure in this setting was greater occipital nerve block, with the majority of studies being small and non-controlled. The techniques, as well as the type and doses of local anesthetics used for nerve blockade, varied greatly among studies. The specific conditions treated also varied, and included both primary (eg, migraine, cluster headache) and secondary (eg, cervicogenic, posttraumatic) headache disorders. Trigeminal (eg, supraorbital) nerve blocks were used in few studies. Results were generally positive, but should be taken with reservation given the methodological limitations of the available studies. The procedures were generally well tolerated. Evidently, there is a need to perform more rigorous clinical trials to clarify the role of PNBs and TPIs in the management of various headache disorders, and to aim at standardizing the techniques used for the various procedures in this setting.

Sonographic visualization and ultrasound-guided blockade of the greater occipital nerve: a comparison of two selective techniques confirmed by anatomical dissection

BACKGROUND

Local anaesthetic blocks of the greater occipital nerve (GON) are frequently performed in different types of headache, but no selective approaches exist. Our cadaver study compares the sonographic visibility of the nerve and the accuracy and specificity of ultrasound-guided injections at two different sites.

METHODS

After sonographic measurements in 10 embalmed cadavers, 20 ultrasound-guided injections of the GON were performed with 0.1 ml of dye at the classical site (superior nuchal line) followed by 20 at a newly described site more proximal (C2, superficial to the obliquus capitis inferior muscle). The spread of dye and coloration of nerve were evaluated by dissection.

RESULTS

The median sonographic diameter of the GON was 4.2 x 1.4 mm at the classical and 4.0 x 1.8 mm at the new site. The nerves were found at a median depth of 8 and 17.5 mm, respectively. In 16 of 20 in the classical approach and 20 of 20 in the new approach, the nerve was successfully coloured with the dye. This corresponds to a block success rate of 80% (95% confidence interval: 58-93%) vs 100% (95% confidence interval: 86-100%), which is statistically significant (McNemar's test, P=0.002).

CONCLUSIONS

Our findings confirm that the GON can be visualized using ultrasound both at the level of the superior nuchal line and C2. This newly described approach superficial to the obliquus capitis inferior muscle has a higher success rate and should allow a more precise blockade of the nerve.