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

Abstract

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) 10 min after the block; 1.18 (±2.04) 2 h after the block and 2.13 (±1.64) 24 h 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.

Keywords
Post-dural puncture headache; Caesarean operations; GON block

Resumo

Justificativa:

A cefaleia pós-punção dural (CPPD) é uma complicação importante da anestesia neuroaxial e mais frequentemente observada em grávidas. A dor é descrita como intensa, perturbadora, e sua localização é geralmente fronto-occipital. O tratamento conservador da CPPD consiste em repouso no leito, fluidoterapia, analgésicos e cafeína. O tampão sanguíneo peridural é o padrão ouro de tratamento, mas é um método invasivo. O nervo occipital maior (NOM) é formado por fibras sensoriais com origem nos segmentos C2 e C3 da medula espinhal e é o principal nervo sensorial da região occipital. O bloqueio do NOM tem sido usado para o tratamento de muitos tipos de dor de cabeça. O objetivo deste estudo retrospectivo foi apresentar os resultados de CPPD tratada com bloqueio do NOM no período de um ano em nosso instituto.

Métodos:

Foram incluídas no estudo 16 pacientes diagnosticadas com CPPD e submetidas a bloqueio de NOM após cesariana. Os bloqueios do NOM foram feitos com levobupivacaína e dexametasona como o primeiro tratamento imediatamente após o diagnóstico de CPPD.

Resultados:

A média dos escores EVA das pacientes foi de 8,75 (±0,93) antes do bloqueio; 3,87 (±1,78) 10 minutos após o bloqueio; 1,18 (±2,04) duas horas após o bloqueio e 2,13 (±1,64) 24 horas após o bloqueio. Efeitos adversos não foram observados.

Conclusões:

O tratamento da CPPD com bloqueio do NOM parece ser um método minimamente invasivo, fácil e eficaz, especialmente após cesarianas. O bloqueio do NOM pode ser considerado antes da aplicação de um tampão sanguíneo peridural.

Palavras-chave
Cefaleia pós-punção dural; Cesarianas; Bloqueio do NOM

Introduction

Post-dural puncture headache (PDPH) is an disturbing complication of neuroaxial anesthesia and occurs approximately in 1.5% of cases ranging from 0.19% to 3.6% in different units.¹ PDPH is more frequently noted in pregnant women receiving neuroaxial anesthesia.² The typical location of the headache is usually bifrontal and/or occipital. It is described as severe, disturbing and debilitating pain that is increasing in the upright position while decreasing or completely disappearing in the supine position.³ According to the International Headache Society, headache develops within 5 days after the dural puncture and resolves either spontaneously within 7 days or within 48 h after effective treatment of the spinal fluid leak.⁴ The conservative treatment of PDPH usually consists of fluid theraphy, analgesics and caffeine. Epidural blood patch (EBP) 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.⁵ It is the main sensory nerve of the occipital region. GON blockage has been used successfully for the treatment of cervicogenic headache, occipital neuralgia, cluster headache, and migraine.^5,6 Accompanying clinical symptoms of PDPH are very similar to those of cervicogenic headache that have been effectively treated with occipital nerve blockade.⁷ GON block is reported to be used for treatment of PDPH in individual cases and in one controlled study.^8-10 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

After the improvement of Local Ethics Committee, the patients who had been diagnosed to have PDPH, and performed GON block as the first choice treatment after caesarean operations were determined from the anesthesia department records and included in the study. The following parameters had been received from the anesthesia department records: the type and diameter of the needle, the time when the headache started postoperatively and when the GON block performed, the visual analog score (VAS) of the patients before the GON block, 10 min, 2 h and 24 h after the GON block. If there is an increment in intensity of pain at the evaluation at 24th hour; time of increment of pain, VAS after the increment of pain, any need for a second block. If a second block is performed; VAS of the patients 2 h and 24 h after the second GON block

All the headaches occurring after regional anesthesia are firstly evaluated by anesthesia department. For the diagnosis of PDPH, the criteria established by International Headache Society had been used.¹¹ The diagnostic criteria is as follows: (1) headache: (a) worsens within 15 min of sitting or standing; (b) improves within 15 min after lying down; (c) must have one of the following: (i) neck stiffness; (ii) tinnitus; (iii) hypacusia; and (iv) photophobia; (2) dural puncture has been performed; (3) headache develops within 5 days after dural puncture; and (4) headache resolves: (a) spontaneously within 1 week (95% of cases); and (b) within 48 h after epidural blood patch (EBP). All the patients who had been diagnosed to have PDPH were informed about conservative theraphy, EBP and GON block. Patients who refused bed rest, demanded early mobilization and also refused an EBP as a first choice treatment were informed about GON block and it had been emphasized to these patients that this was not a routine treatment for PDPH. Before the block, informed consent was obtained from the patients, explaining that the procedure was not routine treatment. As GON block is not a routine treatment for postdural puncture headache, the patients were observed closely and during GON block period the records were kept strictly.

GON blocks were performed as the first treatment directly after diagnose of the PDPH. All the blocks were performed by the same two anesthesiologist who had ten years experience in anesthesia. Following routine monitorization (blood pressure, pulse oximetry, 3-lead electrocardiogram), an iv access was secured. Bilateral blockade of the GON was performed by the method which is based on the anatomical landmarks. The GON is located approximately two thirds of the distance on a line drawn from the center of the mastoid to the external occipital protuberance (Fig.1).^12,13 External occipital protuberance (EOP) was palpated and a needle was inserted between 15 mm and 25 mm lateral to the EOP parallel to the superior nuchal line. 2.5 mL of treatment solution was injected each side. The treatment solution consisted of levobupivacaine 2.5 mg mL⁻¹ (Chirocaine 50 mg/10 mL ampoule, Abbott) and dexamethasone 1 mg mL⁻¹ (Onadron 8 mg/2 mL ampoules, İ.E. Ulagay İlaç Sanayii Türk A.Ş.). A second block was performed if the VAS score is higher than 3. If second block is performed, only levobupivacaine 2.5 mg mL⁻¹ (Chirocaine 50 mg/10 mL ampoule, Abbott) without dexamethasone was used. Sensory changes such as numbness or sensory loss of the dermatome was checked after the GON block. If there were no sensory changes, it was decided that the block was failed. Together with GON blockade, oral hydration had been commenced. Vasovagal syncopal attack, transient dizziness following the injection, intravascular injection of the local anesthetic solution are reported as adverse affects of GON block.^14,15 Any adverse effects during and after the block were recorded. Patients were examined on the third and seventh day after the block.

Figure 1
The GON located approximately two thirds of the distance on a line drawn from the center of the mastoid to the external occipital protuberance.

Results

In our institution 7864 patients had underwent spinal anesthesia for caesarean operations between January and December 2013. 289 patients had been evaluated for headache. 213 patients had been diagnosed to have PDPH. Conservative theraphy had been used for 188 patients, EBP had been used for 9 patients and GON block had been used for 16 patients as the first choice treatment. Among the patients who had been threatened with conservative theraphy; 92 patients had adequate analgesia, 73 patients had inadequate analgesia but refused any other therapeutic options and EBP was used for 23 patients.

All of our patients received spinal anesthesia for caesarean operation. The demographical characteristics of the patients are detailed in Table1. None of our patients had preeclampsia, history of headache or any neurological disorder. Spinal blocks are performed using 26 gauge needles with an atraumatic bevel (Atraucan^®, B-Braun, Germany). No complications occurred during the operations. The mean duration for the start of the complaints of the typical symptoms of PDPH was 34.37 (±17.11) h after dural puncture. The mean duration for performing GON block was 44.06 (±20.01) h after dural puncture.

Table 1
Demographic characteristics of the patients.

	Mean ± SD
Age (years)	29.87 (±3.84)
Height (cm)	163.87 (±4.19)
Weight (kg)	74.34 (±3.40)
BMI (kg m−2)	27.73 (±1.36)

The mean VAS score of the patients was 8.75 (±0.93) before the block; 3.87 (±1.78) 10 min after the block; 1.18 (±2.04) 2 h after the block and 2.13 (±1.64) 24 h after the block. At the evaluation at 24th hour, there was an increment in intensity of pain of 6 patients. The mean time for increment in pain intensity was 17.71 (±3.77) h after the GON block. Only 2 of these 6 patients had VAS scores higher than 3 and needed a second block. The VAS scores of the rest were lower than or equal to 2. At the evaluation 2 h and 24 h after the second block, these patients’ VAS scores were lower than 2. One patient's VAS score did not change two hours after primary GON block and an EBP is performed to this patient (Table2). No adverse effects were observed. At the evaluation on the third day and seventh day of the GON block, none of the patients needed any other treatment option (the VAS scores of all the patients were 0 or less than 2). None of the patients reported any adverse events.

Table 2
The onset time, GON block time, painless duration and the intensity of pain.

N	Start of pain after dural puncture (h)	GON block time (h)	VAS1	VAS2	VAS3	VAS4	Time of increment in pain intensity (after GON block) (h)	2nd GON block time (after increment of pain intensity) (h)	VAS5	VAS6
1	48	50	9	2	0	0	–	–	–	–
2	24	26	8	3	2	2	–	–	–	–
3	72	96	8	1	0	0	–	–	–	–
4	12	26	8	4	2	2	–	–	–	–
5	20	25	7	2	0	2	20	–	–	–
6	20	24	9	2	0	2	16	–	–	–
7	36	40	9	2	0	5	13	8	1	0
8	12	28	8	5	0	2	24	–	–	–
9	48	52	10	4	2	2	–	–	–	–
10	24	26	10	8	8		–	–	–	–
11	24	31	10	4	0	2	20	–	–	–
12	36	49	8	5	1	0	–	–	–	–
13	30	48	10	5	0	3	15	–	–	–
14	36	50	8	5	0	6	16	10	2	0
15	48	52	9	5	2	2	–	–	–	–
16	60	82	9	5	2	2	–	–	–	–

• VAS1, VAS before GON block; VAS2, VAS 10 minutes after GON block; VAS3, VAS 2 hours after GON block; VAS4, VAS 24 hours after GON block; VAS5, VAS 2 hours after the second GON block; VAS6, VAS 24 hours after second GON block.

Discussion

Loss of cerebro spinal fluid (CSF) through dural hole results in a decrease in CSF volume and pressure. This CSF volume and pressure loss may cause downward traction on the pain-sensitive intracranial veins and meninges, as well as the cranial nerves.^3,8 It is not possible to explain PDPH only with traction theory. The bimodal theory suggests that there is a combination of both low CSF pressure and resultant cerebral vasodilatation in reaction to the stretching of vessels.² Pregnant women are particularly prone to PDPH.^16,17 Additionally, the intensity of PDPH in obstetric patients is reported to be significantly higher compared with the other patients.¹⁸

The conservative treatment of PDPH consists of bed rest, non-steroidal anti-inflammatory drugs (NSAIDs), caffeine and weak opioid analgesics. A decrease in the duration and severity of headache, need for any other therapeutic option (e.g. EBP), improvement of daily activity is expected from the treatment modality. Whereas, Sprigge et al. reported that bed rest and mild analgesics did not give effective pain relief for more than 14% of patients suffered from PDPH.¹⁹ Studies comparing the effects of conventional medical treatment and EBP, report that results did not evidence any reduction of pain during the 24 hours of follow up in the conventional medical treatment group¹⁸ and more patients in the EBP group felt better at 24 h compared with the conservative group (89% vs. 19%).²⁰ Bed rest does not appear to affect the course of PDPH.^21,22 One recent meta analysis showed that the efficacy of oral and IV caffeine administration was of no benefit.²³

The most effective treatment for PDPH is EBP, which involves the injection of autologous blood into the epidural space. EBP is an invasive method and has many side effects. It may contribute to development of back pain, lumbar vertebral syndrome, transient bradycardia, and an increase in body temperature.²⁴ Longer term complications are rare but examples include meningitis, arachnoiditis, lumbovertebral syndrome and radicular pain.²⁵

Therapeutic epidural blood patch reported to decrease PDPH and severe PDPH over conservative treatment.²⁶ The cumulative probability of complete recovery was 84% after 1 week in patients allocated to EBP and 14% in patients allocated to conservative treatment.²⁰

Although an epidural blood patch remains the definitive treatment for PDPH, surveys about the management of PDPH in different units and countries present that most respondents first treated the patients conservatively. In surveys about UK, German and Turkish practice; 71%, 94.5% and 64% of responders are reported to perform EBP after the failure of conservative measures respectively.^27-29 National Obstetric Anesthetic Database showed that EBP was performed within two days of delivery in only 42% women.³⁰ In this situation, as mentioned above many patients are left to a relatively low effective treatment period. Any other treatment modality which is more effective than conservative treatment and less invasive than EBP is seems to be needed.

A possible treatment method for PDPH is GON blockade. The rationale for using greater occipital nerve block comes from the proximity of sensory neurons in the upper cervical spinal cord to the trigeminal nucleus caudalis (TNC) neurons and the convergence of sensory input to TNC neurons from both cervical and trigeminalfibres.³¹ The convergence within the trigeminocervical nucleus allows the bidirectional exchange of sensory information between the trigeminal and the upper cervical spinal nerves.³² Since the branch of greater occipital nerve arising from C2 root is responsible for the innervation of deep paraspinal muscles and suboccipital configurations, greater occipital nerve blockade inhibits the stimulations arising from these regions innervated by the greater occipital nerve.³³ This blockade ensures the interruption of pain transmission via the occipital nerves or their component nerve roots or ganglia. The analgesia obtained after the block may be explained by the central neuromodulatory effect that causes decreased central sensitization as a result of the temporary interruption of afferent input to the dorsal roots and trigeminal nucleus.³⁴ It is not clear why, considering the etiology, the headache stopped definitively. Reducing nociceptive traffic through a temporary neural blockade in a sensitized system may allow “winding-down” of central sensitization. Ongoing pain on the basis of peripheral sensitization could also be enhanced through the same process.¹² Neurological examinations and radiological investigations should be considered in persistent postspinal cases so that neurological complications can be ruled out.

We observed that the GON blockade was effective in stopping PDPH after caesarean operations. The mean VAS score of the patients was 8.75 (±0.93) before the block; 3.87 (±1.78) 10 min after the block; 1.18 (±2.04) 2 h after the block and 2.13 (±1.64) 24 h after the block. Only one of our patients had neither sensory loss of the dermatome nor a decrease at VAS score 10 min and 2 h after block, this was evaluated failure of the block and the patient was convinced for EBP. The pain of this patient stopped after EBP. Our results are consistent with the previously reported cases and a study comparing the effects of GON block with conventional theraphy.

Matute et al.⁸ reported the effect of bilateral GON blockage on PDPH with 2 cases. Neither patient had responded to conservative treatment then a block was performed using a mixture of 4 mL 0.25% bupivacaine and 20 mg triamcinalone. The pain resolved within 1-2 min and the patients were discharged 48 h later. Takmaz et al.⁹ reported a case in which a PDPH did not respond to conservative therapy and resolved within 2 min with a GON block performed with 2 mL of 0.5% bupivacaine. 12 h after the block, he reported mild pain that did not restrict his daily activity. The blocks were repeated, where upon his pain completely disappeared. Naja et al.¹⁰ compared the effect of bilateral GON blockage on PDPH with conventional treatment and reported that the pain resolved completely using 1 or 2 injections in 68% of the patients while the remaining 32% required 3 or 4 injections. We used a mixture of levobupivacaine 0.25% and dexamethasone 1 mg mL⁻¹ and injected 2.5 mL each side. It is mentioned that local anesthetics with steroid was more effective than local anesthetic alone for suboccipital injection.³⁵

It is important to stop PDPH especially after caesarean operations because it often interfares with maternal-infant interaction. The patients are most comfortable when they are in supine position but much obstetric patient is unable to do this because of the newborn baby. It is reported in a study designed to investigate the patient experience following accidental dural puncture complicating obstetric epidural analgesia that, after headache, bed rest was a major complaint of the patients; many patients could only get relief from their headache when supine but found nursing and feeding a baby extremely difficult when prostrate; 47% patients complained that being confined to bed was the worst aspect.³⁶ In our study group after application of GON block, patients were mobilized and could be able to nurse and breastfeed their babies easily. For this reason, GON blockade is seems to be more useful after caeserean operations compared with other surgery types.

GON block is used for different types of headaches, its adverse effects are previously evaluated.¹⁴ The adverse effects of GON block are reported as vasovagal syncopal attack, transient dizziness following the injection, alopecia around the injection site and exaggerated headache.¹⁵ Greater occipital nerve has superficial location leading to lesser complications; however, there is intravascular injection risk, which can be reduced by careful aspiration. None of these occurred in our 16 patients. Alopecia around the injection side is a longer time complication; we made explanation about this complication to our patients, no patient appealed with the complaint of alopecia.

One of the limitations of our study is lack of control group. The effectiveness of GON block could be compared with the conservative therapy but in our institution the records of the patients who had been threatened with conservative therapy had not been kept as strict as the patients who had been threatened with GON block. A controlled randomized study is needed for comparing the efficiency of the methods. Another limitation of our study is the possibility of investigator bias.

In conclusion, treatment of PDPH with GON block is seems to be a minimal invasive, easy and effective method especially for patients like new mothers A GON block may be considered before the application of a blood patch. Well-designed controlled studies are needed to assess the role of GON block in the treatment of PDPH.

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Publication Dates

• Publication in this collection
  Sep-Oct 2016

History

• Received
  3 Dec 2014
• Accepted
  23 Mar 2015