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Spontaneous spinal epidural haematoma in pregnancy
- Manjit George, Baburaj Chakrapani (4 January 2007)
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Re: Spinal haematomas following regional anaesthesia
- Nicolette LK tam (18 May 2006)
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Re: Clopidogrel - some unanswered questions.
- Nicolette LK Tam (18 May 2006)
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Clopidogrel - some unanswered questions.
- Shilpa Rahul Sawant, Dr Manasi Bhagwat, SpR Anaesthetics (18 May 2006)
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Spinal haematomas following regional anaesthesia
- Richard G Davies, Nicola A. Harris (14 March 2006)
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Re: Epidural Haematoma - need for early recognition and surgery
- Nicolette L.K Tam, Chen Pac-Soo (28 February 2006)
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Re: Epidural Haematoma
- Nicolette L.K Tam, Chen Pac-Soo (28 February 2006)
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Epidural Haematoma
- Reginald Edward, Anita Samaan and Jacob Dertavitian (15 February 2006)
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Epidural Haematoma - need for early recognition and surgery
- Senthil Kumar Muthu (26 January 2006)
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Manjit George, Doctor, Anaesthetics Fairfield General Hospital, UK, Baburaj Chakrapani
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It is with great interest that we read the article on epidural haematoma after regional anaesthesia in a patient treated with clopidogrel and dalteparin. We would like to share an interesting case that we encountered in our institution. A 21 year old primigravida was referred to our hospital with bilateral paraplegia and persisting sensory loss below T4 on the first day after spinal anaesthesia for Caesarean section. The spinal block was performed under strict aseptic precautions using a 25 gauge Quincke needle with a single attempt at the L3/4 interspace. The CSF was clear and 1ml 5% hyperbaric Lignocaine was instilled. There were no immediate anaesthetic or surgical complications. The patient denied back pain or dyspnoea. There was no significant past medical history and the patient was not taking any regular medications. She didn’t give history of any bleeding tendencies. The antenatal history was remarkable only for the Cephalo Pelvic Disproportion, for which she underwent the Caesarean section. There was no known family history of bleeding tendencies. On neurological examination, she had hypotonia and MRC Grade 0 power in both lower limbs. Abdominal reflexes were absent. Plantar reflex was equivocal bilaterally. Deep tendon reflexes in lower limb were absent bilaterally. Sensation was absent in all modalities below the level of T4. There was spinal tenderness to palpation at C7, T1 and T2, but there was no neck stiffness. She was febrile to touch and the temperature recorded was 38 degrees celsius. She was admitted to the medical ward with the provisional diagnosis of acute transverse myelitis and differential diagnosis of infectious myelopathy. The patient was subjected to further investigations. CSF analysis was normal. MRI scan done on day one showed no evidence of epidural abscess or haematoma or any definite evidence of transverse myelitis. Patient was treated with the provisional diagnosis of transverse myelitis with high dose IV steroids and antibiotics for 5 days. As there was no clinical improvement, repeat MRI (higher resolution) was done on day five, which surprisingly showed epidural haematoma with compression of cord T2 to T4-5!!! Patient was transferred to Neurosurgical unit for emergency dorsal laminectomy. Intra operative findings revealed epidural haematoma at T2,T3, T4 level. The haematoma was evacuated. The neurological status of the patient did not improve in the post operative period. Muscle power of both lower limbs remained Grade 0 with absence of sensations below T4. After 1 month, although there was no neurological improvement, patient was discharged home and was advised physiotherapy. Although true incidence is unknown, literature search suggests that the incidence of spinal epidural haematoma following spinal anaesthesia is 1 in 220,000(1) The incidence of spontaneous spinal epidural haematoma is even further low. Spinal epidural haemorrhage may be spontaneous or idiopathic in origin. Spinal epidural space is the most common site for spontaneous intra spinal haemorrhage. In males, spontaneous spinal EDH most frequently occurs in the lower cervical region whereas in females, it is in the thoracic region(2) Pregnancy related epidural haematoma is even rare entity and only five documented cases have been reported (3,4,5) We presume that, what we had was a case of spontaneous spinal epidural haematoma, in a pregnant patient. Probable cause of bleeding is thought to be the rupture of the venous epidural plexus during a sudden elevation of thoracic or abdominal pressure. To put it in other words, spinal epidural haematoma can still occur in a young otherwise healthy patient with a normal coagulation profile, who is not on any anti coagulants, receiving a central neuraxial block, performed by an experienced anaesthetist, after a clean single puncture, using a small gauge needle!! Definitely, precaution prevents pitfalls!! Factors which might prevent such disasters include avoiding central neuraxial blocks in high risk patients, proper pre operative investigations, and use of correct technique. High degree of suspicion and continuous neurological monitoring for post operative neurological deficits is warranted. If there is any clinical suspicion, an early detection using MRI scan might lead us to early surgical intervention, which is the only ray of hope. Having said that, cases of spontaneous resolution of spinal epidural haematoma have been reported, but its very rare thing to happen, if there is severe neurological deficit. Spreading of the haematoma throughout the epidural space is the most likely hypothesis proposed for spontaneous recovery in case of neurological impairment. The chronological characteristics of an MRI of a spinal epidural haematoma are similar to those seen with intracranial haemorrhage(6) . In the first 6 hours or the hyperacute stage, spinal epidural haematoma appears isointense to the spinal cord on T1 weighted images, and mildly hyperintense and heterogeneous on T2 weighted images, as a result of the presence of intracellular oxyhaemoglobin. In the period ensuing this (7–72 hours) the haematoma is still isointense on T1 weighted images, but becomes hypointense on T2 weighted images, due to presence of intracellular deoxyhaemoglobin. Eventually the haematoma becomes hyperintense and homogeneous on T1 and T2 weighted images as the concentration of methaemoglobin increases. Probably a high resolution MRI scan, with better T2 weighted images would have picked up the epidural haematoma on day one!! References 1) Tryba M. Epidural regional anaesthesia and low molecular heparin: Pro. Anasthesiol Intensivmed Notfallmed Schmerzther 1993; 28:179-181 2) Journal of Neurosurgery 1998 May, 88, 909-11 3) British Journal of Radiology 2004 , 77, 881-884 4) Yonekawa Y, Mehdorn M, Nishikawa M. Spontaneous spinal epidural hematoma during pregnancy. Surg Neurol 1975;3:327–8 5) Carroll S, Malhotra R, Eustace D, et al. Spontaneous spinal extradural hematoma during pregnancy. J Matern Fetal Med 1997;6:218 6) Holtas S, Heiling M, Lonntoft M. Spontaneous spinal epidural hematoma. Findings at MR imaging and clinical correlation. Radiology 1996;199:409–33 Conflict of Interest:None declared |
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Nicolette LK tam, SHO Stoke Mandeville Hospital
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Dear Editor, We would like to thank Dr Davies et al for their interest and comments regarding the case report. By publishing this case report we hope to maintain and increase awareness of a complication that although rare can have devastating consequences for the patient. It is often easier in retrospect to see the sequence of events and the combination of physical signs suggesting an epidural haematoma. With reference to our case the patient did complain of back pain although she was known to suffer from a degenerative spine. However I agree that in combination with the abnormal neurology that subsequently developed such “red flag” signs should cause one to immediately consider an epidural haematoma. Although the physiotherapist noted some abnormal neurology, this information was not conveyed to the duty anaesthetic team. Guidelines in our hospital have since been reviewed to ensure adequate monitoring of patients receiving central neuraxial anaesthesia. Any suspicion of an epidural haematoma should in the first instance involve stopping or reducing the infusion to assess if the signs regress. Further regular assessment is necessary due to the narrow window of opportunity for intervention as mentioned by Dr Davies. The unfortunate delay between the time from when the haematoma was suspected to obtaining an MRI was due mainly to the need to transfer the patient to another hospital. Conflict of Interest:None declared |
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Nicolette LK Tam, SHO Stoke Mandeville Hospital
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Dear Editor We would like to thank Dr Sawant and Dr Bhagwat for their interest in our case report. Clopidogrel has an irreversible effect on platelet function and at the time of the incident the manufacturers recommendations was to stop the agent 7 days prior to surgery. However since this case we have changed practice in our department to stopping clopidogrel ten days prior to elective surgery. Bleeding time is not an ideal measurement of platelet function in patients on antiplatelet agents and as mentioned modified thromboelastography 1 (TEG) may become a necessary test to assess such patients . A preoperative bedside test would resolve issues regarding platelet function in such patients, especially as the use of combinations of antiplatelet agents is becoming more prevalent. Although guidelines are present for the performance of neuraxial blocks on patients receiving anticoagulants there are few recommendations for peripheral blocks. There have been case reports of severe bleeding complications including fatal outcomes in patients that have undergone lower extremity peripheral nerve blocks 2 and ASRA guidelines 2 have suggested that recommendations for performing these blocks should be similar to those for neuraxial blocks. Performing a central neuraxial block on patients receiving antithrombotic medication is usually a risk benefit analysis and commonly the population receiving such agents are often the ones that benefit most from a neuraxial or regional technique. The incidence of epidural haematomas is rare and is based on retrospective analysis and case reports but the neurological outcome can be devastating for the patients. By reporting such cases we hope to increase awareness of this complication and vigilance in all patients receiving central neuraxial anaesthesia. 1. Craft RM, Chavez JJ, Snider CC, Muenchen RA and Carroll RC. J Lab Clin Med. 2005; 145: 309-315. 2. Horlocker TT, Wedel DJ, Benzon H, Brown DL et al. Regional Anaesthesia and Pain Medicine 2003; 28: 172-197. Conflict of Interest:None declared |
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Shilpa Rahul Sawant, SHO Anaesthetics Queen Elizabeth Hospital, Kings Lynn, Dr Manasi Bhagwat, SpR Anaesthetics
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Editor- We read with interest the case report by Tam NLK, Pac-Soo C and Pretorius PM describing epidural haematoma following combined spinal epidural anaesthesia for total knee arthroplasty in a patient receiving clopidogrel. This case highlights importance of vigilance in these patients. The antiplatelet effect of clopidogrel is irreversible and it can take upto 10 days for recovery of platelet function. Despite adhering to ASRA guidelines and recommendations the patient unfortunately developed a rare but potentially devastating complication of central neuraxial blockade. We wonder if current recommendation from ASRA (stopping clopidogrel 7 days before neuraxial blockade) needs to be reviewed(1). The risk of combined spinal epidural (CSE) in patients treated with newer antiplatelet agents is unclear. The routine laboratory tests for assessing coagulation are not effective for monitoring platelet function inhibition with these agents. Modified thromboelastography could prove useful for monitoring reversal of clopidogrel inhibition(2). Altered coagulation is recognised as an important risk factor in the development of spinal haematoma. Peripheral nerve blockade (PNB) may be less risky alternative to central neuraxial blockade in unilateral lower limb arthroplasty(3). The increasing use of clopidogrel may alter the balance of argument in favour of PNB and against CSE in setting of orthopaedic procedure. References: 1. Horlocker TT, Benzon H, Brown DL, et al. Regional anaesthesia in the anticoagulated patient: defining the risks (the Second ASRA Consensus Conference on Neuraxial Anesthesia and Anticoagulation). Reg Anesth Pain Med 2003; 28: 172-97. 2. Craft RM, Chavez JJ, Bresee SJ, et al. A Novel modification of the Thromboelastograph assay, isolating platelet function, correlates with optical platelet aggregation. J Lab Clin Med 2004; 143: 301-9 3. Mentegazzi F, Danelli G, Ghisi D, et al. Locoregional anesthesia and coagulation. Minerva Anesthesiol 2005;71:497-99. Conflict of Interest:None declared |
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Richard G Davies, Consultant Anaesthetist University Hospital of Wales, Nicola A. Harris
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Editor-We read with interest the recent case report in which a patient treated with clopidogrel and dalteparin developed an epidural haematoma following a combined spinal-epidural anaesthetic.1 Although the authors describe the commonly quoted incidence of spinal haematoma following epidural and spinal anaesthesia between 1 in 150 000 and 1 in 220 000, the true incidence is unknown. The Victorian Consultative Council on Anaesthetic Mortality and Morbidity (VCCAMM) is a system that monitors, analyses and reports on key areas of potentially preventable anaesthetic mortality and morbidity within the Victorian hospital system in Australia.2 It has recently reported a number of major complications following regional anaesthesia techniques with concerns regarding the delay in diagnosis and treatment of neurological compromise.3 Unfortunately Tam and colleagues in their discussion omit practical advice on how spinal haematomas can be diagnosed, given the necessity for an urgent response to begin corrective treatment within a narrow 6-12 hour ‘window of opportunity’. VCCAMM has responded with useful advice to detect such complications.3 Common presenting signs and symptoms of neurological compression include onset of new severe or persistent back pain, loss or change of motor function (which may be erroneously attributed to the local anaesthetic), major change in sensory level or density, any deterioration in observed parameters from a pre-existing steady state, and most importantly there must be recognition of the need to communicate urgently with an anaesthetist or acute pain team. It is disappointing that the patient had complained of back pain in the evening of the day of surgery with abnormal neurology detected the day after surgery and yet there was a 48 hour delay after removing the epidural catheter before obtaining a magnetic resonance imaging (MRI) scan to detect what is a neurosurgical emergency. However, the authors are to be congratulated on publishing and highlighting a complication that we believe is under reported. If a spinal haematoma is suspected, an urgent MRI or CT myelogram and neurological or neurosurgical referral within hours is essential. Clearly, the diagnosis of spinal haematomas is difficult. However, given the ever increasing use of clopidogrel, low molecular weight heparins and other newer anticoagulants, we agree with Tam and colleagues that it is vital that we increase our vigilance and close neurological monitoring of these patients who undergo spinal and/or epidural anaesthesia. R. G. Davies* N. A. Harris Cardiff, UK *E-mail: rgd@btinternet.com 1 Tam NL, Pac-Soo C, Pretorius PM. Epidural haematoma after a combined spinal-epidural anaesthetic in a patient treated with clopidogrel and dalteparin. Br J Anaesth 2006; 96: 262-5 2 Victorian Consultative Council on Anaesthetic Mortality and Morbidity. Available from http://www.health.vic.gov.au/vccamm/index.htm 3 Victorian Consultative Council on Anaesthetic Mortality and Morbidity. Neurological Complications of Regional Anaesthesia - Early Consultation with the Anaesthetist. 2005. Available from http://www.health.vic.gov.au/vccamm/articles/neuro.pdf Conflict of Interest:None declared |
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Nicolette L.K Tam, SHO Anaesthetics Wycombe General Hospital, Chen Pac-Soo
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Dear Editor- We would like to thank Dr Muthu for his interesting comments to the case report. It is important to identify any risk factors that may increase the likelihood of developing an epidural haematoma including age, gender and any spinal bony pathology. Although the patient was subsequently found to have osteoporotic wedge compression fractures of her lumbar spine, the operator who performed the combined spinal – epidural anaesthetic reported no difficulty in the placement of either needle or catheter and there was no bloody tap reported. As Dr Muthu mentioned, an MRI is the gold standard method for detecting an epidural haematoma; however a delay was incurred as transfer to another hospital was required in this case. The importance of early diagnosis and treatment cannot be understated and useful neurological recovery usually necessitates treatment within hours after symptoms have developed. Finally although the physiotherapist noted weakness in the non-operated leg this information was not conveyed to duty medical staff, thus incurring further delays before a diagnosis of an epidural haematoma could be made. Conflict of Interest:None declared |
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Nicolette L.K Tam, SHO Anaesthesia Wycombe General Hospital, Chen Pac-Soo
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Dear Editor- We would like to thank Dr Edward et al for their interesting comments with regard to the case report. At the time of the incident preoperative administration of Dalteparin for thromboprophylaxis was as per hospital guidelines in accordance with European guidelines1. It is generally accepted that the first dose can be given preoperatively provided a minimum of 10-12 hours precedes needle placement. However I accept that preoperative dosing has been a matter of controversy in particular as you pointed out that it may have no benefit with regard to thromboprophylaxis. Since this incident the guidelines at our hospital have been changed in accordance with those issued by the American Society of Regional Anesthesia 2. The first dose, half of the maintenance dose of LMWH is administered 6-8 hours post-operatively and the subsequent dose, the full maintenance dose 24 hours after the latter. Dr Edward argued that a more dilute solution would allow neurological monitoring whilst still providing analgesia. A more dilute solution would result in a lesser degree of motor blockade than the solution used above, but there is no evidence that it would result in an earlier detection of spinal haematoma. Risk factors for an epidural haematoma consist of patient, pharmacologic and anaesthetic factors. Identifying risk factors and establishing guidelines will never fully eliminate the risk of developing an epidural haematoma however we must remain ever vigilant whilst performing neuraxial blockades to these rare but important complications. 1.Tryba M. European practice guidelines: thromboembolism prophylaxis and regional anaesthesia. Regional Anesthesia and Pain Medicine 1998; 23:178-82. 2. American Society of Regional Anesthesia and Pain Management. Regional anesthesia in the anticoagulated patient: defining the risks; anesthetic management of the patient receiving low-molecular-weight heparin (LMWH). Available at: http://www.asra.com Conflict of Interest:None declared |
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Reginald Edward, Consultant Anaesthetist Hull and East Yorkshire Hospitals NHS Trust, Anita Samaan and Jacob Dertavitian
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Editor - We read with interest the case report regarding epidural haematoma after a combined spinal epidural anaesthetic in a patient treated with Clopidogrel and dalteparin1. We are surprised at the practice of administering LMWH 10 to 12 hours preoperatively before placing a continuous epidural catheter. The accepted timing of the first dose of thromboprophylaxis has been a matter of controversy but recent studies have clearly established that the use of a preoperative dose does not result in a clinically important improvement in effectiveness compared to the regimen in which the first dose of Dalteparin is administered 6 hours post operatively. But this might have serious implications when a neuraxial anaesthetic technique is planned. Meta analysis by Hull and colleagues 2 and Strebel and colleagues3 concluded that there was no evidence that preoperative prophylaxis would be more efficacious than postoperative thromboprophylaxis. The American Society of Regional Anesthesia 4 has issued new guidelines for neuraxial anaesthesia especially if using continuous epidural anaesthesia in patients receiving prophylaxis with LMWH. For once daily regimen, such as Dalteparin, the recommended timing of the first dose is 6 to 8 hours postoperatively, and the subsequent dose to be given not sooner than 24 hours later. For patients undergoing elective TKR, the American College of Chest Physicians 5 has recommended either routine thromboprophylaxis using LMWH [grade 1A evidence] or the optimal use of Intermittent Pneumatic Compression as an alternative option to anticoagation prophylaxis [grade 1B evidence]. We routinely use IPC and advocate peripheral nerve blocks and early mobilization to prevent catastrophic PE. Epidural analgesia may be useful for postoperative pain relief following major limb joint replacements. However with multi-modal analgesic techniques their benefits may be limited to the early [4 to 6 hours] postoperative period. Since retention of urine, itching, low BP and failure to mobilize early are more frequent in the epidural group we routinely use a more peripheral nerve block technique in combination with a spinal anaesthetic. The authors have used a continuous infusion of 0.25 % bupivacaine but it’s our opinion that a more dilute local anaeshtetic solution would allow for neurological monitoring while still providing adequate analgesia. Monitoring for cord compression in the peri-operative period is crucial with typical initial complaint being new onset weakness or numbness, which will be masked by higher concentrations of epidural solutions. The first symptom is never severe radicular pain. According to the literature the first neuromuscular symptom of spinal haematoma was muscle weakness in 40 % of patients and sensory deficit in 14 % of patients. To summarize there is no evidence for routine preoperative thrombo- prophylaxis in elective TKR. Performing epidural and spinal on patients given LMWH preoperatively can lead to disastrous consequences. Reference: 1. Epidural haematoma after a combined spinal–epidural anaesthetic in a patient treated with clopidogrel and dalteparin. N. L. K. Tam1, C. Pac- Soo1 and P. M. Pretorius, British Journal of Anaesthesia 96 (2): 262–5 (2006) 2. Hull R, Pineo G, Stein P, et al. Timing of initial administration of low- molecular-weight heparinprophylaxis against deep vein thrombosis in patients following elective hip arthroplasty: a systematic review. Arch Intern Med 2001; 161:1952–1960 3. Strebel N, Prins M, Agnelli G, et al. Preoperative or postoperative start of prophylaxis for venous thromboembolism with low-molecular-weight heparin in elective hip surgery? Arch Intern Med 2002; 162:1451–1456 4. American Society of Regional Anesthesia and Pain Management. Regional anesthesia in the anticoagulated patient: defining the risks; anesthetic management of the patient receiving low-molecular-weight heparin (LMWH). Available at: http://www.asra.com 5. Lassen, Clifford W. Colwell and Joel G. Ray, William H. Geerts, Graham F. Pineo, John A. Heit, David Bergqvist, Michael R. Prevention of Venous Thromboembolism: The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004;126;338-400 Conflict of Interest:None declared |
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Senthil Kumar Muthu, SHO-Anaesthetics Arrowe Park Hospital
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Dear Editor, It was very interesting to read the case report of epidural haematoma following combined spinal epidural anaesthesia. I appreciate the authors for providing the readers with the pictures of epidural haematoma. Even though the occurance of a haematoma in the epidural space is a rare event when it occurs it causes devastating consequences to the quality of life of the patient. Spontaneous development of haematomas in the epidural space is unlikely to occur. Always there is an element of human error whenever it has been reported. I would like to raise few points which is appears conflicting in the case report. Firstly, this patient was reported as having wedge compression fractures of bodies of T12,L1,L3 and a partial collapse of L3 in the MRI performed to rule out epidural haematoma. Were these problems not picked up prooperatively which could contribute to a difficult spinal and epidural. Secondly, there appears to be a substantial delay in performing MRI which is a gold standard to pick up epidural haematomas. Thirdly, when the patient complained of severe pain in the lumbar region, which is irrelevant to the site of surgery, it should have been carefully assessed. Finally, I could not understand why a neurology opinion was not saught when the physiotherapist reported weakness and numbness in the affected leg even though it could occur due to a motor block. Conflict of Interest:None declared |
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