Mild Traumatic Brain Injury in Patients on Long-Term Anticoagulation Therapy: Do They Really Need Repeated Head CT Scan?

doi:10.1016/j.wneu.2016.05.061

World Neurosurgery

Volume 93, September 2016, Pages 100-103

https://doi.org/10.1016/j.wneu.2016.05.061 Get rights and content

Background

Mild traumatic brain injury (mTBI), defined as blunt trauma to the head resulting in witnessed loss of consciousness, definite amnesia, or witnessed disorientation with a Glasgow Coma Scale (GCS) score of 14 or 15 is a common occurrence in the emergency department. In mTBI, oral anticoagulation is known to be an important risk factor for hemorrhage. Clinical guidelines recommend baseline computed tomographic (CT) scan and observation for 24 hours plus a CT scan before discharge.

Methods

We compared the non-anticoagulated and anticoagulated patients presenting at our emergency department with mTBI and no neurologic signs (GCS = 15). Every non-anticoagulated patient underwent only a baseline CT scan, whereas the anticoagulated group underwent a second CT scan after a 24-hour observation period.

Results

Between April 2012 and April 2013, we observed 908 adult patients with mTBI and a GCS score of 15; 74 patients (8.1%) were taking oral anticoagulant drugs as long-term therapy, whereas the remaining 834 patients (91.9%) were not. In the non-anticoagulation group, 38 patients (4.6%) were positive for hemorrhage. Two patients underwent neurosurgical intervention. In the anticoagulation group, 5 patients (6.8%) were positive for hemorrhage. No patient underwent neurosurgical intervention. None of them died. The differences between the two groups were not statistically significant.

Conclusions

Patients with a GCS score of 15 who are taking long-term anticoagulation therapy and who present with mTBI have a risk of cranial hemorrhage that is likely to be similar to that of non-anticoagulated patients. It may be reasonable to envision a protocol including only one CT scan and an appropriate observation period.

Introduction

Mild traumatic brain injury (mTBI), defined as blunt trauma to the head resulting in witnessed loss of consciousness, definite amnesia or witnessed disorientation with a Glasgow Coma Scale (GCS) score of 14 or 15¹ is a common occurrence at the emergency departments worldwide. There are various clinical guidelines in the literature (e.g., Canadian head CT rules, New Orleans rules, National Institute for Health and Care Excellence) attempting to define which patient should undergo head computed tomography (CT) scan for patients with mTBI.1, 2, 3 Canadian CT head rules are largely the most widely used.

Nowadays the anticoagulation therapy is increasingly being prescribed by physicians. It has been estimated that approximately 4 million Americans are taking long-term anticoagulation therapy, and 7 million people are doing so worldwide.⁴ Canadian CT head rules do not include mTBI-anticoagulated patients in their criteria. The majority of the studies in literature do not examine these subgroup of patients because there is a general feeling about the high risk of brain hemorrhage in this particular segment of population,⁵ especially in older patients.⁶ Some national protocols7, 8 suggest the performance of two subsequent CT scans, a baseline one at the admission and one after an observation period. In everyday clinical practice, the most difficult decisions must be made when handling patients with no neurologic sign (GCS score of 15). Physicians have to balance the real benefits for the patient against the costs of the examination and the potential damage arising from brain irradiation.9, 10 In this study, we aim to verify the risk for hemorrhage in anticoagulated patients suffering from mTBI with a GCS score of 15 (i.e., those with absolutely no neurologic sign) in an attempt to determine whether these patients really need 2 consecutive CT scans.

Section snippets

Materials and Methods

After obtaining ethics board approval from our institution, we have retrospectively analyzed 3021 consecutive patients presenting to the emergency department of Varese, Italy, with traumatic head injury from April 2012 to April 2013. Eight hundred thirty-four patients had mTBI, and matched Canadian head CT rules criteria for the performance of CT scan and a GCS score of 15, whereas 74 matched the same criteria but were taking long-term anticoagulation therapy. We have excluded from this

Results

Nine hundred eight adult patients were assessed for mTBI and a GCS score of 15. Mean age at the moment of trauma was 67.5 years (range 18–98 years; mean 75 ± 22.5 years). Four hundred thirty-eight patients were male (48.3%) and 470 (51.7%) were female. The vast majority (689, 75.8%) of patients were triaged as green codes, followed by yellow codes (206, 22.6%), white codes (9, 1%), and red codes (4, 0.4%). The causes of trauma were registered by emergency physicians as follows: accidental fall

Discussion

In clinical practice, many patients who suffer from mTBI undergo head CT scan (approximately 30% of subjects with GCS score of 14 or 15); this is true even when physicians scrupulously comply with clinical guidelines.¹¹ Head CT scan is undoubtedly highly sensitive in discerning cerebral hemorrhage after blunt trauma to the head; however, it often turns out to be negative in patients suffering from mTBI.¹² In the literature, there is increasing evidence of the potentially harmful effects of

Conclusions

In patients with a GCS score of 15 and long-term anticoagulation therapy who are presenting at the emergency department with mTBI, the risk of hemorrhage is comparable to that in non-anticoagulated patients. It is therefore potentially useful to limit both the radiologic and clinical assessments to a single CT scan followed by an appropriate observation period.

Acknowledgments

The authors thank Lorenzo Emilitri, information technology engineer in Stabio, Switzerland, who provided invaluable help and patience during data collection, statistical analysis, and writing of this study, and Stefano Uccella, author and physician, who read this article before publication and provided valuable advice.

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Analysis of Clinical and Laboratory Risk Factors of Post-Traumatic Intracranial Hemorrhage in Patients on Direct Oral Anticoagulants with Mild Traumatic Brain Injury: An Observational Multicenter Cohort
2023, Journal of Emergency Medicine
Assessing the risk of intracranial hemorrhage (ICH) in patients with a mild traumatic brain injury (MTBI) who are taking direct oral anticoagulants (DOACs) is challenging. Currently, extensive use of computed tomography (CT) is routine in the emergency department (ED).
This study aims to investigate whether the clinical and laboratory characteristics presented at the ED evaluation can also estimate the risk of post-traumatic ICH in DOAC-treated patients with MTBI.
A retrospective observational study was conducted in three EDs in Italy from January 1, 2016 to March 15, 2020. All patients treated with DOACs who were evaluated for an MTBI in the ED were enrolled. The primary outcome of the study was the presence of post-traumatic ICH in the head CT performed in the ED.
Of 930 patients on DOACs with MTBI who were enrolled, 6.8% (63 of 930) had a post-traumatic ICH and 1.5% (14 of 930) were treated with surgery or died as a result of the ICH. None of the laboratory factors were associated with an increased risk of ICH. On multivariate analysis, previous neurosurgical intervention, major trauma dynamic, post-traumatic loss of consciousness, post-traumatic amnesia, Glasgow Coma Scale score of 14, and evidence of trauma above the clavicles were associated with a higher risk of post-traumatic ICH. The net clinical benefit provided by risk factor assessment appears superior to the strategy of performing CT on all DOAC-treated patients.
Assessment of the clinical characteristics presented at ED admission can help identify DOAC-treated patients with MTBI who are at risk of ICH.
Risk of delayed intracranial haemorrhage after an initial negative CT in patients on DOACs with mild traumatic brain injury
2022, American Journal of Emergency Medicine
Citation Excerpt :
Concussion, in the present study was found to be associated with the presence of delayed ICH, is widely reported to be a risk condition for the traumatic brain injury patient. Uccella et al. suggested that the absence of concussion, even in the anticoagulated patient, limits the risk of ICH, while Easter et al. had previously suggested that in the absence of concussion the presence of ICH resulted in a low risk of neurosurgical outcome [26,27]. Therefore, even for patients on DOACs, it seems that careful assessment of the clinical condition at admission may be predictive of general and delayed ICH [16,24].
Repeat head CT in patients on direct oral anticoagulant therapy (DOACs) with minor traumatic brain injury (MTBI) after an initial CT scan without injury on arrival in the Emergency Department (ED) is a common clinical practice but is not based on clear evidence.
To assess the incidence of delayed intracranial haemorrhage (ICH) in patients taking DOACs after an initial negative CT and the association of clinical and risk factors presented on patient arrival in the ED.
This retrospective multicentre observational study considered patients taking DOACs undergoing repeat CT after a first CT free of injury for the exclusion of delayed ICH after MTBI. Timing between trauma and first CT in the ED and pre- or post-trauma risk factors were analysed to assess a possible association with the risk of delayed ICH.
A total of 1426 patients taking DOACs were evaluated in the ED for an MTBI. Of these, 68.3% (916/1426) underwent a repeat CT after an initial negative CT and 24 h of observation, with a rate of delayed ICH of 1.5% (14/916). Risk factors associated with the presence of a delayed ICH were post-traumatic loss of consciousness, post-traumatic amnesia and the presence of a risk factor when the patient presented to the ED within 8 h of the trauma. None of the patients with delayed ICH at 24-h repeat CT required neurosurgery or died within 30 days.
Delayed ICH is an uncommon event at the 24-h control CT and does not affect patient outcome. Studying the timing and characteristics of the trauma may indicate patients who may benefit from more in-depth management.
Decision tree analysis to predict the risk of intracranial haemorrhage after mild traumatic brain injury in patients taking DOACs
2021, American Journal of Emergency Medicine
Citation Excerpt :
Second, the decision tree seems to confirm something that was already widely known in the management of general MTBI: the presence of a concussion (post-traumatic TLOC/post-traumatic amnesia) identifies subgroups of patients at increased haemorrhagic risk, even among patients on DOACs [16,20]. Uccella et al. found a relatively high incidence (8%) of intracranial haematoma in patients on OAT who, despite a GCS score of 15 at the time of assessment, presented with post-traumatic loss of consciousness, post-traumatic amnesia or disorientation [21]. Fuller et al. reported that in asymptomatic and neurologically unaffected patients in whom the only risk criterion for imaging was the presence of OAT, the risk of ICH was close to 0% [6].
Although the preliminary evidence seems to confirm a lower incidence of post-traumatic bleeding in patients treated with direct oral anticoagulants (DOACs) compared to those on vitamin K antagonists (VKAs), the recommended management of mild traumatic brain injury (MTBI) in patients on DOACs is the same as those on the older VKAs, risking excessive use of CT in the emergency department (ED).
To determine which easily identifiable clinical risk factors at the first medical evaluation in the ED may indicate an increased risk of post-traumatic intracranial haemorrhage (ICH) in patients on DOACs with MTBI.
Patients on DOACs who were evaluated in the ED for an MTBI from 2016 to 2020 at four centres in Northern Italy were considered. A decision tree analysis using the chi-square automatic interaction detection (CHAID) method was conducted to assess the risk of post-traumatic ICH after an MTBI. Known pre- and post-traumatic clinical risk factors that are easily identifiable at the first medical evaluation in the ED were used as input predictor variables.
Among the 1146 patients on DOACs in this study, post-traumatic ICH was present in 6.5% (75/1146). Decision tree analysis using the CHAID method found post-traumatic TLOC, post-traumatic amnesia, major trauma dynamic, previous neurosurgery and evidence of trauma above the clavicles to be the strongest predictors associated with the presence of post-traumatic ICH in patients on DOACs. The absence of a concussion seems to indicate subgroups at very low risk of requiring neurosurgery.
The machine-based CHAID model identified distinct prognostic groups of patients with distinct outcomes based on clinical factors. Decision trees can be useful as guides for patient selection and risk stratification.
Risk factors associated with intracranial bleeding and neurosurgery in patients with mild traumatic brain injury who are receiving direct oral anticoagulants
2021, American Journal of Emergency Medicine
Citation Excerpt :
Preliminary published data show that the rate of ICH after MTBI in patients on DOACs is close to 5% [12-14]. Consequently, an extensive use of CT scan may appear disproportionate [15,16]. Pre-traumatic and post-traumatic risk factors identified in the last two decades have not been verified in patients treated only with DOACs [6,12].
The established clinical risk factors for post-traumatic intracranial bleeding have not been evaluated in patients receiving DOACs yet.
Evaluating the association between clinic and patient characteristics and post-traumatic intracranial bleeding (ICH) in patients with mild traumatic brain injury (MTBI) and DOACs.
This is a retrospective observational study conducted on three Emergency Departments. Multivariate analysis provided association in terms of OR with the risk of ICH. The performance of the multivariate model, described in a nomogram, has been tested with discrimination and decision curve analysis.
Of 473 DOACs patients with MTBI, 8.5% had post-traumatic ICH. On multivariable analysis, major dynamics (odds ratio [OR] 6.255), post-traumatic amnesia (OR 3.961), post-traumatic loss of consciousness (LOC, OR 7.353), Glasgow Coma Scale (GCS) score < 15 (OR 3.315), post-traumatic headache (OR 4.168) and visible trauma above the clavicles (OR 3.378) were associated with a higher likelihood of ICH. The multivariate model, used for the nomogram construction, showed a good performance (AUC bias corrected with 5000 bootstraps resample 0.78). The DCAs showed a net clinical benefit of the prognostic model.
Clinical risk factors can be used in DOACs patients to better define the risk of post-traumatic ICH.
Risk of Intracranial Hemorrhage and Short-Term Outcome in Patients with Minor Head Injury
2020, World Neurosurgery
To examine the occurrence of traumatic intracranial hemorrhage (tICH) and outcome in patients with minor head injury and assess the probable risk factors.
Patients with minor head injury who visited our hospital from January 2015 to July 2017 were registered consecutively, and enrolled patients were aged ≥18 years, visited within 24 hours of the injury, and had a Glasgow Coma Scale score of 15 at outpatient clinic or before the injury.
Of the 1122 enrolled patients, 55 (4.9%) had tICH. An antiplatelet agent was administered in 114 patients, an anticoagulant agent was administered in 49 patients, and none of them were administered in 948 patients. A multivariate analysis of tICH identified it as a risk factor, showing significant difference between antiplatelet medication (P = 0.0312), fall from stairs (P = 0.0057), traffic accident (P = 0.0117), neurologic symptoms (P = 0.0091), and modified Rankin Scale (mRS) score before trauma (P < 0.0001). We also analyzed association of enlargement of tICH with different parameters and only anticoagulant medication indicated an increased risk (P = 0.0005). Thirty patients (2.6%) were dependent or died at discharge (mRS 3–6). The mRS score before trauma (P < 0.0001), tICH (P < 0.0001), spinal injury (P < 0.0001), and enlargement of intracranial hemorrhage (P = 0.0008) indicated an increased probability of morbidity (mRS 3–6) in multivariate analysis.
Antiplatelet and anticoagulant medications were risk factor for tICH and enlargement of tICH in patients with minor head injury, respectively. A pretrauma condition of disability/dependence is an important risk factor for tICH and outcome.
Detecting delayed intracranial hemorrhage with repeat head imaging in trauma patients on antithrombotics with no hemorrhage on the initial image: A retrospective chart review and meta-analysis
2020, American Journal of Surgery
There is debate regarding routine repeat head computed tomography (CT) in blunt trauma patients on a pre-injury antithrombotic when the initial CT is negative for intracranial hemorrhage (ICH).
Retrospective chart review and systematic literature review with meta-analysis.
In the chart review, 32.1% did not have a repeat head CT and 67.9% did. The delayed ICH incidence between those with and without a repeat head CT was similar (1.7% vs 0, p = .3101). The current study was combined with the identified 24 studies. Delayed ICH with or without routine repeat CT was similar between antiplatelet and anticoagulant categories (1.4% vs. 1.3%, p = .5322). Delayed ICH was lower for patients without routine repeat CT compared to those with routine repeat CT (0.8% vs 1.7%, p = .0008). For this patient population, repeat scans should be discretionary. Routine repeat CT may identify a larger proportion of minor delayed ICH.

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: Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

: Current address for L.U.: Emergency Department, Ospedale Civico di Lugano, Lugano, Switzerland.

: Current address for R.C.: Surgery Department, Clinica Luganese, Lugano, Switzerland.

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Original ArticleMild Traumatic Brain Injury in Patients on Long-Term Anticoagulation Therapy: Do They Really Need Repeated Head CT Scan?

Background

Methods

Results

Conclusions

Introduction

Section snippets

Materials and Methods

Results

Discussion

Conclusions

Acknowledgments

Lancet

Lancet

Ann Emerg Med

Clin Neurol Neurosurg

Indications for computed tomography in patients with minor head injury

N Engl J Med

Warfarin therapy: tips and tools for better control

J Fam Pract

Traumatic brain injury in the elderly: considerations in a series of 103 patients older than 70

J Neurosurg Sci

Guidelines for minor head injured patients’ management in adult age

J Neurosurg Sci

Original Article
Mild Traumatic Brain Injury in Patients on Long-Term Anticoagulation Therapy: Do They Really Need Repeated Head CT Scan?