CLINICAL STUDIES DELAYED POSTTRAUMATIC ACUTE SUBDURAL HEMATOMA IN ELDERLY PATIENTS ON ANTICOAGULATION Eyal Itshayek, M.D. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Guy Rosenthal, M.D. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Shifra Fraifeld, M.B.A. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Xicotencatl Perez-Sanchez, M.D. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Jose E. Cohen, M.D. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Sergey Spektor, M.D., Ph.D. Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Reprint requests: Eyal Itshayek, M.D., Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Kiryat Hadassah, PO Box 12000, Jerusalem, Israel 91120. Email: eyalit@md.huji.ac.il Received, July 5, 2005. Accepted, December 2, 2005. NEUROSURGERY OBJECTIVE: To discuss delayed acute subdural hematoma (DASH), a relatively neglected entity, and to emphasize the potentially elevated risk for DASH among elderly, anticoagulated mild traumatic brain injury (TBI) patients. METHODS: The authors reviewed clinical and radiological data for four patients who had normal neurological examinations and normal computed tomographic scans after mild TBI, and who subsequently developed DASH and deteriorated rapidly. RESULTS: The patients included two men and two women, aged 65 to 86 years, who presented to the emergency department after mild TBI between January 2002 and June 2004. All were treated with chronic anticoagulation or anti-aggregation therapy. They deteriorated owing to DASH from 9 hours to 3 days after TBI. Three of the four patients underwent craniotomy for evacuation of their hematomas. One patient, who suffered only focal neurological deficit, was treated conservatively, and her hematoma gradually resolved. Two patients died and two reached Glasgow Outcome Scores of 3 and 4 after extended inpatient rehabilitation. CONCLUSION: A suspicion of DASH should be raised in elderly, anticoagulated, mild TBI patients, including those who present to the emergency department with Glasgow Coma Scores of 15 and normal computed tomographic scans after injury. Based on our experience, we recommend that elderly, anticoagulated mild TBI patients should be admitted for 24 to 48 hours of observation after injury. KEY WORDS: Anticoagulation, Delayed subdural hematoma, Elderly patients, Intracranial injury, Glasgow coma scale, Mild traumatic brain injury, Subdural hematoma Neurosurgery 58:851-856, 2006 M DOI: 10.1227/01.NEU.0000209653.82936.96 ore than one million patients experience blunt traumatic brain injury (TBI) in the United States and Canada each year, with 66 to 75% of the injuries classified as minor (15, 19, 35). Mild TBI frequently occurs in elderly patients, many of whom are treated with anticoagulants, which are known to increase the risk of bleeding events (14, 22, 32, 38, 45, 46, 49). Most mild TBI patients do not develop significant neurosurgical complications. Retrospective studies report incidence of intracranial lesions on computed tomographic (CT) scans in 16 to 28% of patients (7, 21). More recently, prospective studies have found that 3 to 13% of mild TBI patients with Glasgow Coma Scores (GCS) of 15 had intracranial lesions on CT scans (7, 12, 19, 21, 27, 34, 44). Posttraumatic intracranial hemorrhages, including epidural hematoma (EDH), subdural www.neurosurgery-online.com hematoma (SDH), subarachnoid hemorrhage, intracerebral hemorrhage (ICH), and intraventricular hemorrhage, are usually seen in the initial CT scan. But, a small subset of head trauma patients experience delayed intracranial bleeding. Delayed ICH, delayed EDH, and delayed chronic SDH are discussed in the literature (2, 3, 8, 10, 31, 37, 39, 40, 43, 45, 46), and may occur after a normal CT scan at admission. However, delayed acute SDH (DASH) is rarely reported. Cohen and Gudeman (6) define DASH as acute SDH that is not apparent on the initial CT scan, but appears on a follow-up CT scan during the patient’s post-injury course. They report DASH incidence of approximately 0.5% among operatively treated acute SDH patients at their institution. We present here a group of elderly patients on anticoagulation who experienced DASH VOLUME 58 | NUMBER 5 | MAY 2006 | A851 ITSHAYEK ET AL. after mild TBI. On admission, all patients had GCS of 15, no history of loss of consciousness (LOC) or post-traumatic amnesia, no cranial fracture, no focal neurological deficit, and normal CT scans. All deteriorated owing to DASH within hours or days after their mild trauma. The entity of DASH has experienced a lack of critical focus in the literature (6). Reports of DASH appear only in relation to patients with severe head trauma and/or multiple traumatic injuries (6, 45, 46). The purpose of this article is to add focus to DASH as a distinct entity, to describe the occurrence of DASH in a much more lightly injured subset of patients in whom it has not been reported previously, and to raise the degree of awareness among emergency department physicians towards elderly, anticoagulated mild TBI patients. MATERIALS AND METHODS Hadassah Ein Kerem is the sole Level I Trauma Center in the Jerusalem region, serving a population of 800,000 people. All patients who arrive at the emergency department after experiencing head trauma are evaluated and managed according to accepted neurosurgical standards of care by the neurosurgical resident on call, under the supervision of the attending neurosurgeon. High resolution, contiguous, 3 mm, axial CT head studies, without contrast, with brain and bone windows, are performed on spiral or multidetector systems (Philips, Best, The Netherlands) in all patients on anticoagulation, even following minor head injury. The authors describe their experience treating four mild TBI patients who later deteriorated as a result of DASH. RESULTS Four patients, two men and two women aged 65 to 86 years (mean, 73 yr), who presented to the emergency department after minor head trauma between January 2002 and June 2004, are included in this study. All were treated with chronic anticoagulation medication, and one patient was also on antiplatlet therapy. All patients had a GCS of 15, no history of LOC, no focal neurological deficit, no evidence of cranial fracture, and normal head CT scans on arrival at the emergency department. All subsequently developed DASH, with rapid neurological deterioration. Three of the four patients underwent craniotomy for evacuation of their hematomas. The two male patients died after complicated postoperative courses. One female patient underwent surgical evacuation and rehabilitation, eventually achieving a Glasgow Outcome Score (GOS) of 3. In the second female patient, the hematoma was treated conservatively. She achieved a GOS of 4. Patient 1 An 86-year-old man was hospitalized for treatment of pneumonia. He was receiving 100 mg of aspirin and 40 mg of subcutaneous low molecular weight heparin (enoxaparin) A852 | VOLUME 58 | NUMBER 5 | MAY 2006 daily owing to ischemic heart disease. On admission, the patient’s neurological examination was normal and blood tests, including a clotting screen, were unremarkable. Two days after admission, the patient fainted and hit his head. He was awake and oriented immediately after the fall, with a GCS of 15. Physical examination revealed slight scalp bruising. He had no LOC or amnesia. A head CT scan performed 6.5 hours after the fall revealed moderate brain atrophy with no evidence of intracranial hemorrhage (Fig. 1A). During the next 2 days, the patient did well. On Day 3, the patient was found comatose in his bed, with bilateral, dilated, nonreactive pupils and a decerebrate response to pain (GCS 4). An emergency CT scan revealed a large acute SDH on the right with midline shift (Fig. 1B). The patient underwent an emergency craniotomy with evacuation of a large subdural clot. He expired on postoperative Day 6. Patient 2 A 69-year-old man presented to the emergency department after a fall from his bed. There was no LOC or amnesia, and no sign of cranial fracture. The patient was on anticoagulation with Coumadin (DuPont Pharmaceuticals, Wilmington, DE) owing to a prosthetic aortic valve, and on hemodialysis owing to end-stage renal disease. His initial international normalized ratio (INR) was 2.99. A CT scan obtained 3 hours after the fall revealed an old infarction in the right occipital region and generalized atrophy (Fig. 1C), without evidence of intracranial hemorrhage. He was discharged from the emergency department alert and without focal neurological deficit. Approximately 12 hours after the fall, the patient’s level of consciousness abruptly deteriorated. Upon return to the emergency department, he opened his eyes to voice stimulation and localized to painful stimuli with no verbal response (GCS 9). His pupils were equal and reactive to light bilaterally. There was obvious left-sided weakness. Emergent head CT scanning demonstrated a large right side acute SDH with mass effect (Fig. 1D). Fresh frozen plasma and vitamin K were given concomitantly, before craniotomy and evacuation of the hematoma. After surgery, the patient was conscious with leftside weakness. Postoperative CT scanning revealed fair hematoma evacuation, but the patient experienced a series of infections and died after 3 months. Patient 3 A 65-year-old woman on Coumadin because of mitral valve replacement presented to the emergency department after she fell and experienced minor TBI. She had no history of LOC or amnesia and no sign of cranial fracture. Her neurological exam was normal. Initial head CT scan was without sign of intracranial hemorrhage (Fig. 1E). Her INR was 3.03. After 6 hours of observation, she was discharged home. The following day, she was found unconscious and was transferred immediately to the emergency department. On neurological examination, she did not open her eyes, and responded to pain stimulus with left side pain localization and www.neurosurgery-online.com DELAYED ACUTE SUBDURAL HEMATOMA FIGURE 1. A, head CT scan in an 86-year-old man (Patient 1) obtained 6.5 hours after mild TBI revealing moderate brain atrophy. B, head CT scan in the same patient, performed after abrupt neurological deterioration 3 days after trauma, revealing a large right acute subdural hematoma with mass effect. C, head CT scan in a 69-year-old man (Patient 2), obtained in the emergency department approximately 3 hours after a fall in the nursing home where the patient resided, revealing an old infarction in the right occipital region and generalized atrophy. D, repeat head CT scan, performed 12 hours after the initial fall owing to a sudden deterioration in the patient’s consciousness, with obvious left-sided weakness, revealed a large right side acute subdural hematoma with mass effect and consequent subfalcial herniation. E, initial posttrauma head CT scan in a 65-year-old woman (Patient 3). F, 1 day after her mild TBI, the patient was found unconscious at her home. At readmission, she had right hemiplegia and her left pupil was fixed and dilated. Head CT scanning revealed a large acute subdural hematoma. G, normal head CT scan upon admission in a 72-year-old woman (Patient 4) who was assaulted when her home was burglarized. H, a second CT scan, obtained 1 day later, after the patient developed left leg plegia, revealing acute interhemispheric subdural hematoma. uation of the hematoma were performed. Postoperatively, the left pupil became small and reactive, and a CT scan demonstrated absence of SDH. Eventually the patient improved neurologically, and, 26 months later, she has a GOS of 3. Patient 4 A 72-year-old woman on Coumadin because of a history of paroxysmal atrial fibrillation was assaulted and suffered minor head trauma. She arrived at the emergency department of a community hospital alert and lucid, with no neurological deficit (GCS 15), no history of LOC, and no sign of cranial fracture. Her INR at presentation was 3.2. Her initial head CT scan was normal (Fig. 1G). Her Coumadin was changed to enoxaparin and she was admitted for observation. The next day, she developed severe progressive headache and weakness in her left leg. Repeat head CT scanning revealed an acute interhemispheric SDH (Fig. 1H). She was transferred to our hospital conscious, lucid, and responsive, but with full plegia of the left leg. During the hospitalization, she was treated conservatively owing to clinical and radiological improvement. One year later, she has a GOS of 4. DISCUSSION right side extension (GCS 7). Her left pupil was fixed and dilated. An emergent head CT scan revealed large acute SDH with midline shift (Fig. 1F). She received fresh frozen plasma and vitamin K, and an emergency left craniotomy and evac- NEUROSURGERY Many studies address risk factors in patients with mild TBI (1, 3–5, 12, 13, 19, 23, 27, 29, 40, 47, 48). Although the great majority of these patients make uneventful recoveries, misdiagnosis often results in death, a prolonged vegetative state, or significant disability (3, 7, 16, 24, 25, 27, 28, 40, 41). Thus accurate evaluation and treatment of patients who initially seem to be at low risk is one of the most important factors in the reduction of mortality in head-injured patients (19, 28, 47, 48). Guidelines to determine which mild TBI patients should undergo CT scanning, remain for observation, or be discharged home continue to evolve. It is generally accepted that VOLUME 58 | NUMBER 5 | MAY 2006 | A853 ITSHAYEK ET AL. elderly TBI patients are at greater risk for clinically important brain injury (1, 5, 12, 16, 19, 23, 27, 40, 47, 48). Increasing age is associated with a higher risk of intracranial lesions on CT scans in head-injured patients (5, 18, 19, 22, 27, 47, 48, 51), and elderly patients with ICH tend to have worse outcomes (16, 21, 36). Oral anticoagulation is associated with a significant risk of intracranial bleeding, even after minor head trauma (13, 14, 16, 20, 29, 30, 46). As a result, TBI patients with coagulopathy are often included in a high-risk group regardless of clinical presentation (1, 3, 5, 16, 23, 40, 48). We reviewed several recently proposed guidelines for the management of mild TBI patients, with a special focus on discussion of patients who are older and anticoagulated (13, 19, 23, 40, 46–48). The European Federation of Neurological Societies (48) recommends that patients with a GCS of 15 after mild TBI, who are over 60 years of age or who are on anticoagulation, be admitted to the hospital for 24-hour observation. In a prospective study of 1101 mild TBI patients, Ibanez et al. (23) found positive CT findings to be very significantly related to both coagulation disorder and patients older than 65 years of age. The authors included older and anticoagulated patients in a high risk group. In a prospective study of 520 mild TBI patients, Haydel et al. (19) found that patients over the age of 60 years were three times more likely to have a positive CT scan than younger patients and found age to be one of seven risk factors predicting positive CT findings. Both delayed posttraumatic ICH and EDH have been well described in the neurosurgical literature (2, 6, 17, 33, 37, 39, 45, 50). DASH, however, is rarely mentioned. Cohen and Gudeman (6) described their experience with DASH in patients with severe TBI. The occurrence of DASH is mentioned in several large series of head trauma patients, but without discussion or analysis (1, 7, 12, 31, 46). One commonly discussed mechanism for development of acute SDH is rupture of bridging veins. Cerebral veins empty into the dural sinuses, which are adherent to the inner table of the skull. As the veins cross the subdural space, they have little supporting structure, and are therefore most vulnerable to injury at this point. In the presence of cerebral atrophy, which is common in elderly patients, bridging veins are stretched and transverse a greater distance in the subdural space. Cohen and Gudeman (6) and others (9, 26, 42) suggest that rupture of these veins is the mechanism for DASH in patients with trauma-induced hypotension and/or cerebral edema. In 1961, before the CT era, Drake (11) noted that small, perisylvian cerebral arteries were the origin of bleeding in 11 of 100 operated acute SDH patients. These arteries protrude through the arachnoid and are adherent to the dura mater. He reported that six patients with bleeding of arterial origin experienced delayed deterioration, some owing to subacute SDH, and suggested that this phenomena occurs because of a tiny opening in the ruptured artery. In patients with hypotension, delayed bleeding may develop as blood pressure returns to normal after resuscitation. Suggested mechanisms for the formation of DASH in the presence of cerebral edema and elevated ICP include intense A854 | VOLUME 58 | NUMBER 5 | MAY 2006 treatment to reduce ICP by CSF drainage, administration of mannitol, or evacuation of an accompanying mass lesion. These mechanisms may promote formation of DASH in severely injured trauma patients, and the injuries may well be aggravated by coagulopathy, but they do not explain the occurrence of DASH in the subpopulation of elderly, anticoagulated, mild TBI patients described here. The pathogenesis of DASH in these patients remains obscure. In this series, we report our experience with four mild TBI patients aged 65 to 89 years, with no history of LOC, posttraumatic amnesia, or epileptic seizure, no evidence of cranial fracture or cranial soft-tissue injury, and no evidence of drug use or intoxication. At the first evaluation after trauma, they had normal neurological examinations and normal CT scans. All were on anticoagulation therapy. Three patients deteriorated within 24 hours after TBI. The fourth patient deteriorated during the night, and was found deeply unconscious 72 hours after TBI. Three patients underwent operation. One was treated conservatively, and her hematoma gradually resolved. The two male patients were sicker and eventually died. One of them arrived after deterioration with a GCS of 4, and the second man experienced several unrelated complex medical problems. The two female patients survived with GOS 3 and 4. One of these women, at an age of 65 years, was the youngest patient in the series. The second had an interhemispheric subdural hematoma, and experienced only a focal neurological deficit. This series suggests that DASH occurs in some older mild TBI patients who receive anticoagulation. This is only a small series showing our recent experience, the common denominator in these patients is not fully established, and the pathogenesis for DASH is not understood. However, we wish to raise the degree of awareness among emergency department physicians who treat trauma patients on a daily basis that elderly, anticoagulated patients may face higher risk for acute ICH and delayed deterioration after mild TBI. 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Young HA, Gleave JR, Schmidek HH, Gregory S: Delayed traumatic intracerebral hematoma: Report of 15 cases operatively treated. Neurosurgery 14:22–25, 1984. 51. Zwimpfer TJ, Brown J, Sullivan I, Moulton RJ: Head injuries due to falls caused by seizures: A group at high risk for traumatic intracranial hematomas. J Neurosurg 86:433–437, 1997. I tshayek et al. describe four elderly patients on anticoagulation therapy who experienced delayed acute subdural hematomas after minor head trauma. The authors correctly point out that delayed intracranial hematomas are more commonly described in the brain parenchyma or in the epidural space. They are also correct that most of the delayed subdural hematomas described in the recent literature follow more severe head trauma. They thus apprise the neurosurgical community that a delayed acute subdural hematoma may occur in elderly patients on anticoagulation. Because we do not have a denomination, the incidence is unknown. I was surprised that the authors found these hematomas to be venous in origin. In the older literature, delayed arterial hematomas have been reported to occur (1). It is known that traumatic intracranial aneurysms commonly rupture after a delay. Similarly, I would speculate that the subdural hematomas arose from a damaged vessel that bled in a delayed fashion. I can only assume that, in the cases presented, it was a damaged vein that bled. Patients who “talk and die” have always troubled neurosurgeons. The authors propose that elderly patients on anticoagulants who experience minor head trauma should be observed for 48 hours. It is unsettling that their first patient experienced a fatal subdural hemorrhage 72 hours after his trauma while under observation in the hospital. Monitoring patients for the rare hemorrhage after head trauma poses a challenge to the neurosurgical community. Allan H. Friedman Durham, North Carolina 1. Drake CG: Subdural haematoma from arterial rupture. J Neurosurg 18:597– 601, 1961. tshayek et al. have summarized four cases of elderly patients on anticoagulation or antiplatlet therapy who developed acute subdural hematomas well after presenting with a non-focal neurological exam and unremarkable head computed tomographic scans. Although delayed deterioration is typically encountered with small asymptomatic epidural hematomas that rapidly enlarge several hours after the initial injury, this report emphasizes the importance of close observation for at least 24 to 48 hours in all patients with head trauma, A856 | VOLUME 58 | NUMBER 5 | MAY 2006 Ricardo J. Komotar E. Sander Connolly, Jr. New York, New York T COMMENTS I particularly those with additional risk factors such as antiplatelet therapy or anticoagulation. he authors describe a theoretically well known complication of anticoagulation therapy: hemorrhage after trauma. Their point that actual cases have not been described in the literature is, however, valid. I think this basic clinical observation in four patients merits publication to show that this is not just a theoretical threat, but can be observed in patients. I reviewed the literature and could, to my surprise, not find any comprehensive description of this category of patients. Given economic pressures, these patients may be sent home too early and are then exposed to comparatively high risks of delayed deterioration. We cannot usually heal primary injuries, but we should not fail to prevent fatal deterioration if at all possible. Tiit Mathiesen Stockholm, Sweden T his article on delayed post-traumatic subdural hematomas in the elderly who are anticoagulated should be seen as one part of a greater problem, i.e., the increasing frequency of anticoagulation and the development of intraparenchymal hemorrhages after trivial falls. Many years ago, the Traumatic Brain Injury research group from Hong Kong presented a study on the need to observe the elderly for 48 hours if the head was struck. This provided recognition that the softened, often atrophied, brain is more vulnerable to bleeding. Itshayek et al. focus on subdural hematomas, but this is a relatively limited part of the difficulty. We need to educate Trauma and Emergency Room physicians that patients on anticoagulation must be admitted for at least 24 hours of observation, even with trivial head injuries. Ongoing trials with Factor VIIA may provide evidence that this agent may have utility in these patients. Lawrence F. Marshall San Diego, California T he message of this paper is important for emergency room physicians, neurosurgeons, hospital administrators, and insurance companies. Neurosurgeons who hospitalize patients who are being treated with anticoagulation, who sustain what initially seems to be a minor head injury, are often faced with denial of the admission by insurance companies. In appealing such denials, it is helpful to have a recent article with the message of the devastating outcomes of missed subdurals in the elderly. Robert G. Grossman Houston, Texas www.neurosurgery-online.com