|
 
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| ORIGINAL ARTICLE |
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| Year : 2014 | Volume
: 7
| Issue : 1 | Page : 25-31 |
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Management of postdural puncture headache: greater occipital nerve block technique
Saher M Kamal1, Ghada A Hassan2, Sherif S Wahba1
1 Department of Anesthesia, Ain-Shams University, Cairo, Egypt
2 Department of Anesthesia, Minoufiya University, Menufia, Egypt
| Date of Submission | 30-Jun-2013 |
| Date of Acceptance | 15-Sep-2013 |
| Date of Web Publication | 31-May-2014 |
Correspondence Address:
Ghada A Hassan
MD, Department of Anesthesia, Minoufiya University, Menufia 11341
Egypt
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/1687-7934.128394
Background
Although epidural blood patch remains the gold standard for the treatment of postdural puncture headache (PDPH), it may not be successful in severe and persistent cases. Greater occipital nerve block (GONB) is a novel and easy technique that can be performed in an anesthesia clinic. The present study was carried out to evaluate ultrasound-guided GONB as a line of management for patients with PDPH.
Materials and Methods
We examined 30 patients age range 18-60 years, of both sexes American Society of Anesthesiologists I-II who developed PDPH either after a cesarian section or any operation under spinal anesthesia. Patients were randomized into two groups: the GONB group, which received ultrasound-guided GONB, and the control group, which received medications. Patients were examined for development of PDPH either during hospitalization or within 2 weeks of operation. If headache was not relieved within both groups, epidural blood patch was performed 24-48 h from the start of medical treatment in the control group but from the time of GONB in the study group. We recorded time of improvement or disappearance of headache, amount of analgesic consumption, and any side effects.
Results
Patients in the GONB group showed a statistically significant lower numerical rating score and greater improvement than the control group (P < 0.0001) during the second 12 h. The headache was completely relieved in the GONB group within a significantly shorter time than in the control group: 29.20 ± 14.67 and 73.60 ± 43.47 h, respectively (P = 0.00). Tramadol and pregabalin were consumed significantly less by the participants in the GONB group compared with those in the control group (P < 0.001).
Conclusion
GONB is a potentially useful alternative technique for the management of PDPH. Keywords: Greater occipital nerve block, postdural puncture headache, spinal anesthesia
How to cite this article:
Kamal SM, Hassan GA, Wahba SS. Management of postdural puncture headache: greater occipital nerve block technique. Ain-Shams J Anaesthesiol 2014;7:25-31 |
How to cite this URL:
Kamal SM, Hassan GA, Wahba SS. Management of postdural puncture headache: greater occipital nerve block technique. Ain-Shams J Anaesthesiol [serial online] 2014 [cited 2023 Sep 24];7:25-31. Available from: http://www.asja.eg.net/text.asp?2014/7/1/25/128394 |
| Introduction | |  |
Despite several innovations in the gadgets used and also the techniques of performing a subarachnoid block, postdural puncture headache (PDPH) continues to be a common morbidity following a subarachnoid block [1].
Usually, PDPH is mild in intensity, brief in duration, and can be self-limiting, but in some reports, its symptoms may last for months or years [2],[3]. In addition, PDPH is aggravated by an upright position and associated with visual or auditory disturbances such as photophobia, diplopia, difficult in accommodation and tinnitus, hearing loss and hyperacusis, nausea, vomiting and dizziness, neck stiffness, and scapular pain. In addition, untreated PDPH may lead to cranial nerve palsies and even subdural hematoma. Sometimes, patients with PDPH may have severe symptoms that confine them to bed and may persist for a long period of time, which results in extended hospital stay [4].
Even after one century of description of PDPH by August Bier, the question of the optimal management of PDPH remains unanswered. A wide range of popular therapies, both invasive and noninvasive, are available for the practicing anesthesiologist for the management of PDPH. Epidural blood patch (EBP) remains the gold standard for the treatment of PDPH, although the success rate can be as low as 65% and not 95% as claimed, and may also not be successful in severe and persistent cases [3].
Greater occipital nerve block (GONB) is a safe and easy procedure that can be performed in an anesthesia clinic and leads to more rapid results than medications. Ultrasound (US) GONB is useful to avoid an inadvertent injection into the occipital artery, development of hematoma, and failed blockade because of the wide variability in the courses of occipital artery and nerve. As the anesthesiologist should not leave any stone unturned to prevent PDPH, by optimizing controllable factors such as needle size and shape and to implement all the recently available prevention strategies for this [5], this study was designed.
The aim of this study is to compare medical treatment with US-guided GONB for optimal management of PDPH and to ensure appropriate and safe management of patients with PDPH.
| Patients and methods | | |
This randomized-controlled study was approved by our Review Board (Research Ethics Committee, Faculty of medicine, Ain-Shams university hospital, Cairo, Egypt). After obtaining consent, this study was carried out between March 2012 and February 2013 on 30 patients (aged 18-60 years) of American Society of Anesthesiologists I-II physical status who developed PDPH either after a cesarian section or any operations under spinal anesthesia.
Patients were included in the study if they developed PDPH (complaint of fronto-occipital, nonthrobbing headache, increased with an upright position, and associated with vomiting and/or nausea, photophobia, neck stiffness, and tinnitus) either during hospitalization or within 2 weeks of operation.
Patients with coagulopathy, those who were still continuing on anticoagulant therapy, patients with local scalp infection, patients who had allergy to any anesthetics, and pregnant women were excluded.
Patients who agreed to participate in this study were allocated randomly to two groups: GONB group and control group. Randomization was performed as follows: patients with odd numbers were included in the control group, whereas patients with even numbers were included in the GONB group. In the control group, the patients received medical treatment and if the medical treatment failed (not improved within 24-48 h), they received an EBP. In the GONB group, the patients received US-guided GONB and if it did not improve within 24-48 h, they received an EBP.
The patient and the doctor who administered the US block or prescribed the medications were not blinded to the technique; only the doctor who collected the data was blinded to group to which the patient belonged. All patients were seen by the same investigator, who collected the preprocedure and postprocedure data.
Headache was scored into:
Mild [score 1: numerical rating score (NRS) = 1-4]: slight restriction of their physical activity; the patient was not confined to bed and had no associated symptoms such as diplopia and vomiting.
Moderate (score 2 NRS = 5-7): if patient was forced to stay in bed for part of the day and associated symptoms were not necessarily present.
Severe (score 3 NRS≥8): patients were bed ridden for the entire day, made no attempt to raise their heads or to stand, and associated symptoms were always present.
The control group received medical treatment in the following order: if the score was mild to moderate, from 0 to 12 h after the procedure, patients were advised bed rest, advised adequate hydration, and received paracetamol 1 g (oral) every 6 h, diclofenac 75 mg/12 h (suppository) if the patient had no history of bronchial asthma, and granisetron 1 mg intravenously once daily as an antiemetic.
If the headache score did not improve within 12-24 h or at least 5, the above treatment was replaced by tramadol 50 mg intravenously/12 h and pregabalin 300 mg orally the first time, followed by 150 mg twice daily orally.
If the severity of headache improved and the patient was discharged home, the patient was instructed to take diclofenac 50 mg orally/12 h or paracetamol 1 g orally/8 h and pregabalin 150 mg twice daily orally. Twenty-four to forty-eight hours later, if the headache had not improved, we proceeded to perform an EBP.
The GONB group received medical treatment as the control group in the first 12 h if the score was less than 5. If patients did not improve in the next 12 h or if the score was at least 5 from the start, then the patients received US-guided bilateral GONB.
After 24-48 h, if the headache score did not improve, patients directly received an EBP.
When headache improved, the patient was discharged home and followed up 1 month later for any further problems.
Greater occipital nerve block
The patient was placed prone on a pillow to rest his/her head with a shoulder roll under the thorax and the head was slightly flexed.
The posterior occipital region was prepped in a sterile manner and a block was performed under US guidance using a Sonosite transportable ultrasound (Sonosite, Bothell, Washington, USA) device, where a high-frequency transducer 8-12 MHz linear probe was placed on occipital protuberance in the sagittal plane and moved 3 cm inferior and 1.5 cm lateral to occipital protuberance. Gently, the probe was rolled out from medial to lateral to identify the occipital artery as the nerve is expected to be medial to it, which could be visualized lying between inferior capitus oblique muscle and semispinalis muscle or trapizius and semispinalis muscles.
After a local anesthetic injection to the skin, 1 ml of 1% lidocaine and 2 ml of 0.25% bupivacaine and 20 mg triamcinolone were injected using the out-of-plane technique with a 1.5 inch 21 G standard needle bilaterally. Ten minutes later, a pinprick and cold test were performed along the scalp.
| Epidural blood patch technique | | |
The patient was placed in the lateral decubitus position and the lumbar area was prepped and draped. Once the epidural space was located at the level of the previous dural puncture, 15 ml of venous blood was drawn from the antecubital vein into a plastic syringe using a strictly septic technique. The blood was injected slowly into the epidural space over a course of 30 s.
The following data were collected: headache score (NRS), time of improvement or disappearance of headache completely from the start of medical treatment, time of hospital discharge, any side effects such as bleeding from the scalp, pain in the injection site, dizziness, vasovagal reaction, infection, or nerve damage, and whether the patient needed further analgesics after discharge home, and finally the amount of analgesic consumption.
The primary outcome was to measure the success rate and time needed for pain relief of PDPH as well as analgesic consumption after GONB in comparison with conventional medical treatment. The secondary outcome was to assess the complications during the GONB technique and to measure the need for EBP.
Sample size
A two-group continuity-corrected χ2 -test with a 0.050 two-sided significance level will have 80% power to detect the difference between a medications proportion, p1, of 0.150 and occipital nerve block proportion, p2, of 0.700 (odds ratio of 13.222) when the sample size in each group is 15.
Statistical analysis
Data were statistically described in terms of mean (SD), median and range, or frequencies (number of cases) and percentages when appropriate. Comparison of numerical variables between the study groups was carried out using the Mann-Whitney U-test for independent samples. For comparison of categorical data, the χ2 -test [2] was used. The exact test was used instead when the expected frequency was less than 5. P values less than 0.05 were considered statistically significant. All statistical calculations were carried out using computer programs statistical package for the social science (SPSS Inc., Chicago, Illinois, USA) version 15 for Microsoft Windows.
| Results | | |
Thirty patients were included in the study, with no exclusion from both groups. The two groups had comparable demographic data as shown in [Table 1]. The onset time of PDPH was comparable between both groups (P = 0.88) as shown in [Table 2]. NRS of both groups were comparable at baseline (P = 0.1013) and in the first 12 h (P = 0.7557) as shown in [Table 2]. In the next 12 h, patients in the GONB group showed considerable improvement and statistically the NRS was significantly lower in the GONB group [1 (0-1)] in comparison with the control group [7 (6-8)] as shown in [Table 2] (P < 0.0001).
Nine patients in the GONB group who presented with NRS less than 5 received only medical treatment during first 12 h [Table 3], with a partial improvement in NRS. This led us to perform US-guided GONB in the next 12 h; as a result, eight patients achieved complete pain relief and only one patient continued on medical treatment [Table 3]. Six patients in the GONB group who presented with NRS of at least 5 received US-guided block during the first 12 h; two patients achieved complete pain relief, three patients achieved partial improvement with a resultant need for medical treatment in the next 12 h, whereas the remaining patient did not show improvement and received an EBP as shown in [Table 3]. There was complete relief from headache within 73.60 ± 43.47 h in the control group, whereas in the GONB group, this was achieved within 23.20 ± 14.67 h. This difference was statistically significant (P = 0.00), as shown in [Table 2]. GONB was performed once and all patients who received the block improved considerably and did not require further injections. Time of hospital discharge was significantly shorter in the GONB group in comparison with the control group (P = 0.00) as shown in [Table 2]. Consumptions in the first 24 h were not statistically different between both groups for paracetamol (P = 1.0) and diclofenac (P = 0.57), but a highly significant difference with high consumption was recorded in the control group than in the GONB group for tramadol and pregabalin (P = 0.00) as shown in [Table 4] and [Figure 1] and [Figure 2]. After 24 h, consumptions of diclofenac and pregabalin were statistically higher in the control group in comparison with the GONB group (P = 0.016 and 0.035, respectively) as shown in [Table 4] and [Figure 3]. In the GONB group, 10 patients in the GONB group underwent a completely successful block (66%), four patients showed partial improvement (26%), and one patient did not show improvement and was treated with EBP (6.6%) as shown in [Table 5].
Six patients in the control group and one patient in the GONB group received EBP but this was statistically insignificant (P = 0.554) as shown in [Table 3]. In the GONB group, minor subcutaneous hematoma was noted in eight patients at the injection site, 13 patients complained of pain at the site of injection, one patient developed mild dizziness, and two patients developed vasovagal attack, as shown in [Table 5]. No adverse effects attributed to the analgesic regimen were reported by any patient in the control group.
| Discussion | | |
This prospective comparative randomized-controlled study showed that bilateral GONB relieved the PDPH in a shorter time with lower analgesic consumption and earlier patient discharge home in comparison with traditional medical treatment.
Spinal anesthesia developed in the late 1800s. It remains an easy and cost-effective anesthetic technique [6]. However, PDPH is one of the most common complications of spinal anesthesia [7],[8].
Cerebral spinal fluid (CSF) leakage into the epidural space has been proposed to be the main mechanism responsible for this syndrome [9]. It usually presents as a severe, dull - throbbing, frontooccipital headache that can be severe and is usually aggravated by sitting, standing, and walking because of stretch of pain-sensitive meningeal structures by the descending shift of the brain, which stretches pain-sensitive meningeal structures. Some patients with PDPH have no CSF hypotension; therefore, it can be explained by another theory, which is the Monro-Kellie doctrine, which states that the brain, CSF, and blood volume are constant and decreased CSF volume is compensated by venodilation, which causes headache similar to migraine [10],[11]. The headache typically occurs hours to days after puncture, can sometimes extend to the neck and shoulders, and may also be associated with nausea, vomiting, and visual or auditory disturbance [12].
The most both invasive and noninvasive popular therapies for PDPH are not supported by the best evidences. However, the standard treatment includes bed rest, good hydration, simple analgesics, and caffeine. Invasive procedure EBP remains the gold standard against which all other treatments for a PDPH are compared. The pain relief from an EBP is often immediate. If the EBP worked simply by plugging the dural leak, one would expect that the CSF deficit would take a much longer time to be replenished. It is possible that the EBP works through a second mechanism by increasing pressure in the spinal cord. Although the EBP is usually considered a benign procedure, it is not without its complications [11],[13]. It may contribute toward back pain, neck pain, paresthesias, radicullitis, and fever. Also, its success rate can be as low as 65% and it may not be successful in severe and persistent cases [3],[14]. A lack of success in up to 70% of the cases, as reported in the study by Loeser et al. [15], has also been reported when EBP is performed in the first 24 h following the headache. Therefore, Suna et al. [5] believed that bilateral GONB may be attempted before EPB in severe cases, especially in those who do not respond to conservative treatment in the early period.
The greater occipital nerve (GON), which derives most of its fibers from the C2 dorsal root, is the main sensory nerve of the occipital area. GONB has been used frequently for different types of headache [16]. There is a hypothesis that occipital blockade would result in good pain management and quick return to normal activity in cases of PDPH [17]. This depends on the similarity of the accompanying clinical symptoms of PDPH to those of cervicogenic headache that have been treated effectively with occipital nerve anesthetic blockade [18]. The block reduces the convergence of nociceptive afferents and sensitization of trigemino-cervical neurons and the mechanical hyperalgesia caused by sitting in different positions and walking that might initiate the pain by stimulating the upper cervical nerves supplying the surrounding muscle [19].
The most published studies on this topic are limited by a retrospective design, small sample size, heterogeneous patient groups, and lack of a control arm [20],[21].
In fact, occipital nerve blockade has a long and proven track record of efficacy in the treatment of head and neck pain. A chart review found that 100% of patients with occipital neuralgia who received an occipital nerve block of lidocaine and dexamethasone experienced at least a 50% reduction in original pain [22].
GONB injections are considered quite safe when performed under US guidance by an experienced anesthetist. However, every medical procedure is associated with risks. Sahai-Srivastava and Subhani [23] reported a small proportion of patients who experienced minor tenderness at the injection site, bleeding tissue damage, and infection after receiving an occipital nerve block. These results were in agreement with the results of Matute et al. [24], who were the first to report the effect of bilateral GONB on PDPH. They presented two cases of PDPH treated successfully with bilateral blockade of the GON. Neither patient had responded to conservative treatment (postural measures, hydration, caffeine, and conventional analgesia) or to intravenous hydrocortisone. A block was performed using a mixture of 4 ml 0.25% bupivacaine and 20 mg triamcinalone. The pain resolved within 1-2 min. They did not report any complication in the two patients who were discharged 48 h later. In the GONB group in our study, there was minor subcutaneous hematoma in 53.3%, pain in 86.6%, vasovagal in 13.3%, and dizziness in 6.6%, but there was no major complication (infection or nerve damage) 0%.
During this study, the onset of headache and the NRS pain scores were not statistically significant. Fortunately, at the second 12 h, the NRS pain score was significantly lower (P < 0.001) in the GONB group when compared with the control group. Also, the difference in the consumption of analgesics between the two groups was statistically significant. These results were in agreement with the results of Naja and colleagues, who studied 50 adult patients with PDPH divided randomly into two equal groups of 25 patients each. All patients in the block group received either both GON and lower occipital nerve blocks, or GON and lower occipital nerve with facial nerve blockade according to the onset of the headache. Each 10 ml of the injected mixture contained 3 ml lidocaine (2%), 3 ml lidocaine (2% with epinephrine 1 : 200 000), 2.5 ml bupivacaine (0.5%), 0.5 ml fentanyl (50 μg/ml), and 1 ml clonidine (150 μg/ml), whereas the control group received adequate hydration with medical treatment. Their results showed that the headache was completely relieved in 68.4% of patients after one or two injections in the block group, with significantly lower visual analog scale pain scores and consumption of analgesics than the study group [18].
We recorded a single case (33.3%) in the GONB group and six cases (60%) in the control group who needed blood patch, but this difference was statistically nonsignificant. Our results showed 66% successful cases with GONB, 26% of cases with partial improvement, and 6.6% of cases who failed to improve.
Both groups showed no statistically significant difference in the scores of headache at discharge, which were 1.27 ± 1.66 and 1.47 ± 1.30 in the GONB and the control groups, respectively, during this study. However, the patients in the block group were discharged from the hospital significantly earlier (P = 0.001); furthermore, they had shorter sick leave time when compared with the control group (P = 0.001). Our results were in agreement with the results of Naja et al. [18], who reported a significant difference (P = 0.001) in the discharge time between the two groups, where the block group left the hospital earlier and had shorter duration of headache when compared with the control group (P = 0.001).
Although we attempted to formulate this research carefully, limitations still exist. First, this research was carried out only on a small size of population. Second, both groups were heterogeneous with respect to the type of surgery.
| Conclusion | | |
Bilateral GONB is a safe and easy technique that relieved PDPH, which did not respond to conservative treatment. Further studies are required to verify the efficiency of GONB in relieving PDPH and to evaluate other blocks.
| Acknowledgements | | |
Study equipment support was provided by institutional resources.
Conflicts of interest
None declared.
| References | | |
| 1. | Gerrtse MB, Gielen MJ.Seven months delay for epidural blood patch in PDPH. Eur J Anaesthesiol 1999; 16:650-651. 
|
| 2. | Acharya RChhabra SS, Ratra M, Sehgal AD. Cranial subdural haematoma after spinal anaesthesia. Br J Anaesth 2001; 86:893-895.
|
| 3. | Safa TV, Thormann F, Malassine P, Henry M, Riou B, Coriat P, Seebacher J. Effectiveness of EBP in the management of PDPH. Anesthesiology 2001; 95:334-339.
|
| 4. | Zeidan A, Farhat O, Maaliki H, Baraka A. Does PDPH left untreated lead to subdural hematoma? Case report and review of the literature. Int J Obstet Anesth 2006; 15:50-58.
|
| 5. | Suna AT, Cigdem UK, Cettin K, Hulya B. Treatment of post-dyral puncture headache with bilateral greater occipital nerve block. Headache 2010; 50:869-881.
|
| 6. | Brown DL, Fink BR In: Cousins MJ, Bridenbaugh PO, editors.The history of neural blockade and pain management. Neural blockade in clinical anesthesia and management of pain 3rd ed. Philadelphia: Lippincott Williams & Wilkins; 1998. p. 3-30.
|
| 7. | Nafiu OO, Salam RA, Elegbe EO. Post dural puncture headache in obstetric patients: experience from a West African teaching hospital. Int J Obstet Anesth 2007; 16:4-7.
|
| 8. | Schneider MC, Schimd M. Post-dural puncture headache. In: Brinbach DJ, Gatt SP, Datta S, editors. Textbook of obestetric anesthesia. Philadelphia, PA: Churchill Livingstone; 2000. p. 487-503.
|
| 9. | Kuczkowski KM. Post-dural puncture headache in the obstetric patient: an old problem. New solutions. Minerva Anestesiol 2004; 70:823-830.
|
| 10. | Hannerz J, Ericson K, Bro Skjo HP. MR imaging with gadolinium in patients with and without post-lumbar puncture headache. Acta Radiol 1999; 40:135-141.
|
| 11. | Harrington BE. Postdural puncture headache and the development of the epidural blood patch. Reg Anesth Pain Med 2004; 29:136-163.
|
| 12. | Naja ZM, EL-Rajab M, AL-Tannir MA, Ziad FM, Tawfiik OM. Repetitive occipital nerve blockade for cervicogenic headache: expanded case report of 47 adults. Pain Pract 2006; 6:278-284.
|
| 13. | Vasder GM, Southern PA. Postdural puncture headache: the role of prophylactic epidural blood patch. Curr Pain Headache Rep 2001; 5:281-283.
|
| 14. | Sandesc D, Lupei MI, Sirbu C, Plavat C, Bedreag O, Vernic C. Conventional treatment or epidural blood patch for the treatment of different etiologies of post dural puncture headache. Acta Anaesthesiol Belg 2005; 56:265-269.
|
| 15. | Loeser EA, Hill GE, Bennett GM, Sederberg JH. Time vs success rate for epidural blood patch. Anesthesiology 1978; 49:147-148.
|
| 16. | Evans RW, Yannakakis GD. Occipital nerve blocks and managed care: a review of the reviewers. Headache. 2001; 41:990-991.
|
| 17. | Naja ZM, AL-Tannir MA, EL-Rajab M, Ziad FM, Baraka A. Nerve stimulator-guided occipital nerve blockade for postdural puncture headache. Pain Pract 2009; 9:51-58.
|
| 18. | Naja ZM, EL-Rajab M, AL-Tannir MA, Ziad FM, Tawfik OM. Occipital nerve blockade for cervicogenic headache: a double-blind randomized controlled clinical trial. Pain Pract 2006; 6:89-95.
|
| 19. | Kehlet H. Postoperative opioid sparing to hasten recovery: what are the issues? Anesthesiology 2005; 102:1083-1085.
|
| 20. | Young WB, Marmura M, Ashkenazi A, Evans RW. Greater occipital nerve and other anesthetic injections for primary headache disorders. Headache 2008; 48:1122-1125.
|
| 21. | Tobin J, Filtman S. Occipital nerve blocks: when and what to inject? Headache 2009; 49:1521-1533.
|
| 22. | Jürgens TP, Müller P, Seedorf H, Regelsberger J, May A. Occipital nerve block is effective in craniofacial neuralgias but not in idiopathic persistent facial pain. J Headache Pain 2012; 13:199-213.
|
| 23. | Sahai-Srivvastava S, Subhani D. Adverse effect profile of lidocaine injections for occipital nerve block in occipital neuralgia. J Headache Pain 2010; 11:519-523.
|
| 24. | Matute E, Bonilla S, Girones A.Bilateral greater occipital nerve block for post-dural puncture headache. Anaesthesia 2008; 63:551-560.
|
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
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