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de Journal of Neurological Sciences [Turkish] 33:(2)# 48; 341-351, 2016 http://www.jns.dergisi.org/text.php3?id=977

Research Article

Characteristics of Intracranial Subdural Hematomas Following Spinal and Epidural Anesthesia in Obstetric Patients

Cezmi Çağrı TÜRK1, Ramazan UYAR1, Niyazi Nefi KARA1, Sevim YILDIZ2, Çağatay ÖZDÖL1, Ramazan Cengiz ÇELİKMEZ1, Tolga GEDİZ1, Mustafa KARASOY1

1Antalya Education and Research Hospital, Neurosurgery, Antalya, Turkey 2Antalya Education and Research Hospital, Radiology, Antalya, Turkey

Summary

Background: Intracranial subdural hematomas (SDH) are quite rare complications of spinal anesthesia and epidural analgesia (SA/EA). Characteristics of the incident in obstetric patients were investigated. Methods: The PUBMED database was searched for three sets of key words: "subdural hematoma and spinal anesthesia", "subdural hematoma and epidural analgesia", "pregnancy and subdural hematoma and epidural anesthesia". The literature findings and our clinic series was reported. Results: The study reached at 26 obstetric cases between the age of 17 and 46 years (mean: 30.7 years). The majority of the patients (65.3%) were giving their first children. There were (34.7%) acute, (23%) sub-acute and (42.3%) chronic cases. Bilateral SDH was seen in 50% of epidural, 30.7% of the total cases. Patients, giving vaginal delivery, were more prone to have acute and sub-acute hematomas (61.5%), compared to Cesarean Section (CS) (53.8%). The mean duration of diagnosis was 379 hours. Patients managed conservatively in 42.3% of the cases. 3/9 of acute cases could be treated conservatively. Patients had favorable outcomes in 88.4%. Conclusions: Delayed diagnosis incurring patients at risk and high level of suspicion and vigilance were needed particularly in patients with headache lasting more than 5 days or non-postural in character, associated with neurological findings.

Key words: Epidural Analgesia, Subdural Hematoma, Obstetric, Spinal Anesthesia, Spinal needle

Doğum Amacı ile Spinal Anestezi ve Epidural Analjezi Yapılan Hastalarda Ortaya

Çıkan Kafa İçi Subdural Hematomların Özellikleri Özet

Amaç: Kafaiçi subdural hematomlar (SH) spinal anestezi ve epidural analjezinin nadir görülen komplikasyonlarındandır. Bu çalışmada doğum ile ilişkili olguların genel özelliklerinin belirlenmesi amaçlanmıştır. Yöntem: Literatür taraması ile bildirilen doğum ile ilişkili subdural hematomları tespit edilmiştir. Bu amaçla 3 anahtar kelime grubu kullanılmıştır: "subdural hematoma and spinal anesthesia", "subdural hematoma and epidural analgesia", "pregnancy and subdural hematoma and epidural anesthesia". Literatür taramasından elde edilen olgular ile kliniğimizde tespit edilen olgular değerlendirilmiştir. Bulgular: Bu çalışma ile 26 hastaya ait veriler derlenmiştir. Hastaların yaşları 17-46 yıl arasındadır (ortalama 30.7 yıl). Hastaların çoğunluğunun ilk doğumlarıdır (65.3%). Subdural

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hematomlar akut (%34.7), subakut (%23) ve kronik (%42.3) olarak sınıflandırılmıştır. Lateralizasyon yanında bilateral SH da görülmektedir; bunların %50'si epidural analjezi yapılanlarda görülmekte, tüm grup içerisinde ise %30.7'u oluşturmaktadır. Normal doğum yapan hastalar daha çok akut ve subakut SH (61.5%) gelişimine yatkındır. Bu oran sezeryan ameliyatlarında (CS) %53.8 dir. Olguların %42.3' ü tutucu yollar ile tedavi edilmiştir. Hastaların %88.4'ünde prognoz olumlu seyretmiştir. Sonuç: SH'ların geç teşhis edilmesi hastaları riske atmaktaır. Bu nedenle doğum sonrası başağrısı olan, özellikle 5 günden uzun süren ve/veya postural özellik göstermeyen ve nörolojik bulgular ile başvuran hastalarda SH akla getirilmeli ve buna yönelik teşhis yöntemlerine başvurulmalıdır.

Anahtar Kelimeler: Doğum ile ilişkili, Epidural analjezi, Spinal Anestezi, Spinal iğne, Subdural hematom

INTRODUCTION

Intracranial subdural hematoma (SDH) is a rare complication of spinal and epidural analgesia (SA/EA). Parallel to increase in numbers of the spinal anesthetic procedures, case reports about post-procedural SDH are increasing. Despite the obscurities regarding basic characteristics, particularly in obstetric cases, the occurrence of SDH is generally appreciated as either a topic of familiarity (particularly by neurologist and neurosurgeons) or a catastrophic consequence of spinal anesthetic procedures, even cause abstinence from the procedures.

The following study was inspired by our institutional experience in obstetric cases. Literature search had revealed turmoil of data which makes drawing conclusions difficult for clinical practice due to embracing heterogenous groups of patients from different disciplines. We believe that defining the characteristic features will raise awareness and vigilance for early diagnosis and accurate management of the obstetric SDH. Morover, the outlining the incident will help physicians to inform their patients for potential consequences of spinal anesthetic procedures in consenting for the procedures.

MATERIAL AND METHODS

Case series

General characteristics of our 5 cases are presented in Table 1.

Case One

A previously healthy, 29-year-old woman admitted after her appearance to ER for severe headache and recent seizure. Examination findings were unremarkable except for moderate post–seizure paralysis (Todd Paralysis) on her left upper extremity. Her medical history revealed giving birth to her first baby 15 days ago with Caesarean Section (CS) under spinal anesthesia. The procedure was performed with 22G spinal needle (Quincke) between L3-4 vertebrae. Chronic subdural hematoma was diagnosed right frontoparietal region on cranial Computerized Tomography (CT) (Fig 1). She was operated on with two burr holes due to severe headache and recent seizure. Postoperative period went well without any remaining neurological deficit. She was discharged from the hospital at 7th postoperative day.

Case two

A twenty-six-year-old woman referred to ER by a family physician for moderate headache and vomiting. Physical examination revealed no neurological deficits. She had a history for CS for her

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first baby with spinal anesthesia 3 week ago. The spinal anesthesia was performed with 22G needle at L3-4 level. She was evaluated with cranial CT for long-lasting headache. A chronic subdural hematoma was diagnosed on the frontal region (Fig 2a). There were also signs of cerebral edema based on sulcal effacement. Conservative managment with pain medications was preferred with close follow up as long as the patient's clinical condition allowed. Control images revealed spontaneous resorption of the subdural hematoma.

Case three

This lady had her first baby at the age of 17 years. She was consulted to neurosurgery by her obstetrician for long lasting headache for the last 18 days. Her medical history revealed a successful labor with epidural analgesia (22G Tuohy needle). First symptoms were dated back to 72 hours after birth. Although being responsive to pain medications, her complaints lasted for 3 weeks. Her neurological examination was not conclusive. The long lasting symptoms warranted CT scan. A right sided collection in the subdural space was shown with sulcal effacements (Figure 2b). Symptomatic treatment for headache and close follow-up was resulted a good outcome.

Case four

A 38-year-old lady first seek medical consultation for her complaint of migraine attack. A neurologist questioned the history and revealed a change in the character of headache in such a way that the last attack was more spread to the head. She described her condition as “never want to get up from bed”. Both change in nature of headache and history of labor for her third baby led to cranial CT scan. After diagnosing chronic SDH on the right frontoparietal region, the patient was referred to neurosurgery. Her good neurological condition and CT findings (no

midline shifts) encouraged us following the patient with conservative management, which yielded positive outcome.

Case five

A 40-year-old lady was given birth to her first baby 25 days ago. She was happy after CS with spinal anesthesia till her first headache after 12 hours of birth. Then the complaints went subtle for the last 2-3 weeks. She was first evaluated by her family physician and later, referred to neurosurgery. Her neurological examination was normal. However, her previous history for spinal anesthesia led to CT scan. A chronic SDH was observed on left frontal region. The relatively benign appearance (i.e. no signs of herniation in cerebral structures) govern the management strategy. Medical therapy and restriction of mobilization concluded with a fine outcome.

Literature search

The National Library of Medicine's PUBMED database was searched for three sets of key words to encompass all cases reported about SDH occurring following spinal anesthetic procedures in obstetric patients: key words was “subdural hematoma and spinal anesthesia”, “subdural hematoma and epidural analgesia” and “pregnancy and subdural hematoma and epidural anesthesia. These three searches retrieved, some of them overlapping, 148, 35 and 36 articles, oldest dating back to 1959, respectively.

Later, the articles in English were taken into further evaluation in order to define characteristics' features. Language criteria discriminated 39, 12 and 7 articles from each of three key words, respectively. Total of 161/219 articles were taken into second stage.

At the second stage, the following criteria were applied to the articles by the two authors (CCT and RU) blinded to each others selections; (1) articles about subdural hematomas related to SA/EA (i.e. not to lumbar puncture, trauma etc) in

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female patients experiencing birth with CS or labor, (2) patients without additional risk factors (such as hemorrhagic diathesis), and (3) without hemorrhagic conditions (such as AVMs, thrombocytopenic disease etc), (4) full-text available articles. During the selection, the authors favored on current diagnosis and management strategies for subdural hematomas. The literature search was limited to articles after CT or MRI era for sake of homogenity regarding prognosis in the population. There were no conflict between the two authors selections.

These criteria eliminated 139/161 articles. One of the articles was republication of the same article. Total of 21 articles taken into the review.

There were multiple case reports in some articles, thus only the obstetric cases were included. The study population was composed of 26 cases (including our 5 cases)(1,2,4,5,7-9,12,15,17,19-21,23,25,27,28,31,33,34).

These cases were analyzed with respect to demographic data, spinal anesthetic procedures, types and size of the needles, level and number of the procedures, occurance of dural puncture, type of birth, (labor or Caesarean section), symptoms and signs, their durations, localization and time-frame for SDH, management strategies and prognosis.

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RESULTS

The study reached at 26 obstetric patients between the age of 17 and 46 years (mean: 30.5 years). Most of the births were at term (19/26:73.1%, others not defined). The parity of the patients (number of given births) could be abstracted from the texts for 22/26 of the cases. Among these, 17

patients were giving their first children (17/26: 65.3 %) and 19.2% (5/26) has already had a previous history of either normal delivery or Cesarean Section (CS). The parity in remaining 4 patients could not being determined from available data. The number for CS and labor was similarly distributed between the spinal and epidural anesthesia (13 and 12 cases, respectively);

Figure 1: a and b) demonstrating CT scans with chronic frontoparietal subdural hematoma on the right side with compressed lateral ventricles and sulcal effacement. The arrows indicate mixed intensity line in the subdural hematoma located in between the cortex and the dura. The early ( c) and late (d) postoperative CT scans showed no residual or recurrent subdural hematoma (arrow heads indicating burr holes).

Figure 2: a and b) demostrating right frontal minimal subdural hematoma with no midline shift (arrows), c and d) are follow up CT scans indicating spontaneous resolution of the subdural hematoma.

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one patient had combined epidural and spinal anesthesia. Subdural hematomas were mainly occurred in patients giving their first child (17/26: 65.3%) (Table 2).

The CS were performed predominantly with spinal anesthesia (9/13: 69.2%), compared to vaginal delivery with epidural analgesia (8/12:66.6%). The majority of patients with EA were giving their first child (9/12:75%). Other three's were not defined in the articles.

There were not a major difference in the rates of particular types of SDH with respect to type of birth and spinal anesthetic procedure (Table 3 and 4). The series revealed a slight dominancy with respect to incidence of chronic SDH (42.3%), followed by acute (34.7%) and subacute cases (23%). However, the distribution of acute SDH demonstrated higher rates of occurance in primiparous women (7/9 of acute cases: 77.7%). Bilateral SDH were more common in vaginal delivery and epidural analgesia groups (53.8% and 50%, respectively) (Table 4).

The most frequently used needles were Tuohy and Quincke style (16/26 cases). These two needle types were associated with SDH in 61.5% (16/26). Quincke needle was the major needle type in

Chronic SDH (5/11), while Tuohy in acute SDH (4/10) (Table 5). Regarding needle sizes, half of the acute cases (5/10) were occurred with thicker needles (18G or lower). This figure changed to thinner needles (22 G or higher) for chronic cases. Symptomatology was also investigated in this study. Headache was the most common symptom.

Regarding the management of SDH; conservative and surgical treatments were implemented in 42.3% (11/26) and 53.8% (14/26) of the cases. The surgery included either burr hole evacuation or craniotomy. Interestingly, three of acute SDHs were treated conservatively (33.3%), while the rest (6 patients) needed craniotomy. Craniotomy is exceptional for chronic cases (one patient), which were mainly managed with conservative methods (6 patients) or with burr hole drainage (3 patients).

The patients had favorable outcomes (23/26: 88.4%); the mortality was reported in acute and chronic case (one patient in each). Moreover, one patient with acute SDH had a minor neurological deficit as a permanent damage following craniotomy (Table 2).

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DISCUSSION

Spinal anesthetic procedures have gained general acceptance and are widely performed before different surgical procedures from a variety of disciplines and patients. This procedures offer some advantages over general anesthesia with

respect to complication rates(2). Perception of “safety” creates a sense of exemption from complications. This inturn renders difficulties in managements in terms of delaying diagnosis and determining clinical significance.

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The complication rate for SAEA are low, yet, challenges the physicians. The spectrum included hypotension, post-dural puncture headaches (PDPH), meningitis, hematomas either in spinal or intracranial region, transient sensory loss and paraplegia(15). Pavlin et al.(24) can be credited for presenting the first case of subdural hematoma in an obstetric patient.

Incidence

The exact number of subdural hematoma (SDH) per SA/EA is difficult to define because none of the figures in formulation is known (total number of SDH and anesthetic procedures)(10,16). However, accidental dural punctures reportedly occured in approximately 0.2-6.6% of the spinal epidural procedures(13). The rate for post-dural puncture headaches (PDPH) was 88% afterwards(29). Scott and Hibbard reported PDPH as the most common complication of dural puncture. On the other hand, the incidence for subdural hematoma was extremely low (1/505.000 cases)(25).

Predisposing Factors in Obstetric Patients

Obstetric patients are not unique with respect to cascade of SDH formation, which is unanimously correlated with cerebrospinal fluid (CSF) leak(11,18). Dural puncture causes CSF loss through the needle orifice and resulting downward displacement of intracranial structures, which inturn stretches the bridging veins. The break at a weak point in these vessels results in bleeding in the subdural space(3,32). Obstetric patients, though, confers some predispositions; first of all, the number of spinal procedures are high in this particular group. Moreover, contractions and valsalva maneuvers increases rate of CSF loss and later, displacement of cerebral structures(2,22).

Our study defined that the hematomas were mainly (65.3%) seen in patients who give birth to first children. In fact, this figure would be much higher because data was not available in some articles. The

occurence of SDH can be attributed to relatively longer duration of delivery and associated contractions in primiparous women. Moreover, we conceived that maternal pushing could be also a factor in acute progression of a SDH. However, any correlation could be determined from neither our data nor from literature search. Indeed, data regarding details of delivery was seldomly reported. The information was abstracted in just 5 cases. The duration of labor was ranged from 2 to 25 hours.

Theoretically, the increase in CSF loss should be proportional to rate of SDH. The factors may be size and type of needles in SA/EA because these two factors may contribute to increase in amount of the leak from puncture site. Similar associations were previously addressed in the literature(6,30).

Vallejo et al.(30) studied 5 needle types aiming at determining which needle is safer for obstetric patients with respect to PDPHs. The pencil-point-needles (i.e. Sprotte and Whitacre) were reportedly safer than Quincke cutting needles(30). However, this comparison is not unequivocally accepted in the literature; even smaller caliber needles were not free of complications, in terms of PDPHs and hematomas in particular(4,34). We could not also reach a clear conclusion regarding a safer needle type based on our review.

Besides, our figures also demonstrated that acute cases were slightly more common in needle sizes 18G or larger (5/9 cases). The needle size is much smaller in case of chronic cases (i.e. 22G or smaller in 63.6%). These numbers may represent that a rather slow loss of CSF from needle orifice can be associated with minor tears in the vessels. The steady accumulation of blood in subdural space may be tolerated and delay the diagnosis, giving a time-frame needed for changes observed in chronic SDH (namely 2 to 3 weeks).

This hypothesis may be also supported by the higher incidence of bilateral SDH

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following epidural analgesia(34). Combining findings regarding increased incidence of both bilateral and acute SDH with large-bore needles in epidural analgesia concluded us that a large scale and further studies are needed to determine exact pathophysiology of SDHs. Our figures and hypothesis needs more support from future studies with respect to significance of labor duration, risks specific to pregnancy, effects of needle types and sizes on occurance of SDHs.

Management and prognosis

Subdural hematomas can be managed either conservatively or surgically, depending on patients' neurological status and size of the hematoma(2,12,27,14). Conservative treatment is particularly reserved for neurologically stable patients. Although the size of hematoma may be misleading in terms of clinical significance, radiological displacement of intracranial structures are also important in determining the management strategy(4). Our study revealed that on the contrary to anticipations, not all patients were managed surgically. Conservative management was preferred in 42.3% (11/26), even in 3 acute SDHs. The outcomes were favorable. Moreover, besides symptomatic treatment with medications, some therapheutic strategies have been described to reduce the risk of SDH by stopping CSF leakage from the needle orifice. Epidural blood patch (EBP) was defined for this purpose in the literature. Despite unpromising results pertaining to EBP in preventing formation of subdural hematoma(6,8). Three patients from the literature were reportedly experienced this method of treatment. One patient later underwent a craniotomy for evacuation of a subacute SDH(28). The outcomes were fine for all patients. Our numbers are limited for discussing any benefit from EBP procedure. But it was interesting that all 3 cases had either acute or subacute SDH. This might reflect severity of headaches or symptoms in these

patients, which rendered physicians for implementing an additional intervention to stop CSF leak.

Surgical treatment was the prodominent method in this series (15/26 cases). Signs and symptoms of the patients governs the decision making such a way that rates of surgery increases parallel to degree of the complaints or neurological findings(21). The type of approach differed basically depending on the period of hematoma; craniotomy was the main method particularly for acute cases (66.6%: 6/9 patients). Burr holes were evenly distributed between subacute and chronic cases (2 and 3 cases, respectively), but not performed in acute cases.

There were two deaths in this series; first patient had bilateral chronic SDH, admitted to the hospital for severe headache and neurological deterioration. The patient died 22 days after giving birth (with epidural analgesia)(9). The other patient (birth with spinal anesthesia), despite being operated on with craniotomy for acute SDH, deceased at postoperative 7th day(33). In spite of these deaths, the prognosis of SDH in obstetric patients seems quite favorable (88.4%). However, delaying the diagnosis still incurs patient at risk. Thus, being aware of characteristic features of PDPH is highly important in diagnosis. PDPH is generally observed within 5 days of the procedure. The positional change in severity and absence of other neurological findings are major discriminating factors(14).

This study has several drawbacks; first of all, the clinical data was predominantly obtained from a literature search in addition to our experience with 5 patients. These informations were limited to English literature, which may render some valuable cases out of our scope. Moreover, previous articles were focused on presence of SDH, per se. The information, that we considered crucial in defining the clinical perspective for sake of this study, was not homogenously presented in many of the

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articles. Specific informations exclusive to pregnancy, such as labor durations, needle types and sizes, associated medications like magnesium sulfate, postoperative immobilizations, were left out of the discussions. Because of that, as many data as possible were abstracted from mixed case series regarding obstetric cases. More homogenous and detailed reports will concentrate on factors attributable to obstetric cases.

Our study is concentrated on the subdural hematomas from a unique perspective. The main objective at defining characterictic features in obstetric patients revealed increased risk for primiparous women after spinal anesthetic procedures. There were no significant difference between epidural analgesia and spinal anesthesia with respect to incidence and type of SDH. However, bilateral SDH were reported in higher incidence in obstetric patients and in particular in those with epidural analgesia. Further researches will also enlighten probable association between labor duration and maternal pushing/ valsalva maneuver on development of SDHs.

Differential diagnosis of postpartum headache is complex. In a patient with previous spinal anesthetic procedure, even if the symptoms, particularly charactheristics of the headache are not typical, the findings can be attributed to post-dural puncture headache. Many intracranial SDH may present as a PDPH. Therefore PDPH does not exclude SDH, even can precede it. Headache in obstetric patients should prompt a diagnostic suspicion for causes other than post-dural puncture headache, particularly when prolonged more than 5 days or the qualities of the pain changes (non postural pain) or new symptoms appear (cognitive changes, altered consciousness, focal neurological signs and seizurs). Neuroimaging tests should be performed in order to exclude more serious causes of headache. High degree vigilance and familiarity are needed

to overcome risk of mortality and morbidity in otherwise favorable SDH in obstetric patients. Conflict of interest: None Correspondence to: Cezmi Çağrı Türk E-mail: drcezmiturk@gmail.com Received by: 10 August 2015 Accepted: 20 March 2016 The Online Journal of Neurological Sciences (Turkish) 1984-2016 This e-journal is run by Ege University Faculty of Medicine, Dept. of Neurological Surgery, Bornova, Izmir-35100TR as part of the Ege Neurological Surgery World Wide Web service. Comments and feedback: E-mail: editor@jns.dergisi.org URL: http://www.jns.dergisi.org Journal of Neurological Sciences (Turkish) Abbr: J. Neurol. Sci.[Turk] ISSNe 1302-1664 REFERENCES

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