Bergenfeldt et al.

International Journal of
International Journal of Emergency Medicine (2023) 16:54
https://doi.org/10.1186/s12245-023-00530-z Emergency Medicine

RESEARCH Open Access

Delayed intracranial hemorrhage

after head trauma seems rare and rarely
needs intervention—even in antiplatelet
or anticoagulation therapy
Henrik Bergenfeldt1, Jakob Lundager Forberg2, Riikka Lehtinen2, Ebba Anefjäll2 and Tomas Vedin1*

Abstract
Background Traumatic brain injury causes morbidity, mortality, and at least 2,500,000 yearly emergency depart-
ment visits in the USA. Computerized tomography of the head is the gold standard to detect traumatic intracranial
hemorrhage. Some are not diagnosed at the first scan, and they are denoted “delayed intracranial hemorrhages. ” To
detect these delayed hemorrhages, current guidelines for head trauma recommend observation and/or rescanning
for patients on anticoagulation therapy but not for patients on antiplatelet therapy. The aim of this study was to inves-
tigate the prevalence and need for interventions of delayed intracranial hemorrhage after head trauma.
Methods The study was a retrospective review of medical records of adult patients with isolated head trauma
presenting at Helsingborg General Hospital between January 1, 2020, and December 31, 2020. Univariate statistical
analyses were performed.
Results In total, 1627 patients were included and four (0.25%, 95% confidence interval 0.06–0.60%) patients had
delayed intracranial hemorrhage. One of these patients was diagnosed within 24 h and three within 2–30 days. The
patient was diagnosed within 24 h, and one of the patients diagnosed within 2–30 days was on antiplatelet therapy.
None of these four patients was prescribed anticoagulation therapy, and no intensive care, no neurosurgical opera-
tions, or deaths were recorded.
Conclusion Traumatic delayed intracranial hemorrhage is rare and consequences mild and antiplatelet and anti-
coagulation therapy might confer similar risk. Because serious complications appear rare, observing, and/or rescan-
ning all patients with either of these medications can be debated. Risk stratification of these patients might have
the potential to identify the patients at risk while safely reducing observation times and rescanning.
Keywords MESH, Brain injuries, Traumatic intracranial hemorrhages, Traumatic anticoagulant tomography, X-ray
computed

Introduction
*Correspondence: Traumatic brain injury (TBI) causes major worldwide
Tomas Vedin morbidity, mortality, and accounts for approximately 3%
tomas.vedin@med.lu.se
1
of emergency department (ED) visits [1]. Up-front assess-
Clinical Research Centre, Department of Clinical Sciences, Skåne
University Hospital, Lund University, Box 50332, 20213 Malmö, Sweden ment of TBI severity and outcome is complex because
2
Clinical Sciences, Helsingborg General Hospital, Lund University, initial signs and symptoms do not always correlate
Svartbrödragränden 3‑5, 25187 Helsingborg, Sweden with the extent of injury [2, 3]. Presently, computerized

© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which
permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the
original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or
other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line
to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this
licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom-
mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 2 of 8

tomography (CT) scan of the head is the gold standard and has about 45,000 visits each year. Neurosurgery is
in TBI to detect important injuries and the diagnostic provided at Skåne University Hospital in Lund which is
accuracy is almost perfect [4]. In 5–10% of TBI patients, 40 km away. Because of this distance, patients with severe
a traumatic intracranial hemorrhage (TICH) is detected traumas that occur closer to Helsingborg General Hospi-
at the first scan [5]. However, a small portion of TICHS tal are brought there for primary interventions. The SNC
is not diagnosed at index-CT and denoted as delayed guideline for TBI was used during the study period.
intracranial hemorrhages (DICHs) [6]. The inclusion criteria were as follows:
The definition of DICH varies, but it is usually divided
into an intracranial hemorrhage found within 24 h after • Patients presenting to the ED with a chief complaint
trauma or between 2 and 30 days [7, 8]. The risk of DICH of “head trauma” registered in the ED information
in patients with an intact coagulation system is consid- system
ered low but higher in patients with anticoagulation • Age ≥ 18 years
therapy (ACT) such as warfarin or direct oral anticoagu-
lants (DOACs). Several studies report the risk of DICH in The exclusion criteria were as follows:
patients with ACT to be 0.2–1.5% [9–13]. However, the
risk of DICH in patients with antiplatelet therapy (APT) • Scheduled ED return visits
is less well studied and has been reported at similar or • Visits managed by a nurse without a physician’s
higher levels as in patients with ACT (1.3 vs. 1.4%) [13, involvement (e.g., patient with trivial trauma triaged
14]. to primary care or self-care)
Current guidelines such as the New Orleans Criteria • Trivial trauma (e.g., trauma to the head without
(NOC), the National Institute for Health and Care Excel- trauma to the neurocranium or a small cut in need of
lence (NICE) guidelines, the Canadian CT Head Rule stitches)
(CCHR), Eastern Association for the Surgery of Trauma • Classified medical records
(EAST) practice management guidelines, and the Scan-
dinavian Neurotrauma Committee Guidelines (SNC) The following parameters were collected and analyzed
take risk of TICH for patients on ACT into account by in the present study:
mandating a head-CT [15–19]. The EAST and SNC
guidelines mandate both CT and observation for 24 h in 1. Age (years)
head-injury patients treated with ACT [18, 19]. However, 2. Gender (male/female)
none of the guidelines recommends screening for DICH 3. Age-adjusted Charlson Comorbidity Index
in patients on APT to the same extent as patients on 4. Head CT performed (yes/no)
ACT. The SNC guidelines recommend extra attention to 5. Head CT outcome (hemorrhage/no hemorrhage)
patients on APT by mandating an up-front CT and dis- 6. Admission to general hospital ward (yes/no)
charge if this is normal [19]. 7. Admission to intensive care unit or neurointensive
Furthermore, the consequences of DICH are poorly care unit (yes/no)
described. A low DICH incidence of 0.5–0.7% with- 8. Neurosurgical intervention (yes/no)
out mortalities for patients on ACT or APT has been 9. Level of consciousness using Reaction Level Scale
reported in low-energy traumas in the elderly [8, 20]. 85 (1–8)
The rationale for performing this study was that the 10. Past illnesses (yes/no)
occurrence and consequences of DICH in head trauma 11. Anticoagulant treatment (no/vitamin-k antagonist/
patients in general and patients on APT/ACT in particu- direct oral anticoagulant/low molecular weight
lar are inadequately explored in the current literature. heparin)
The aim was to study the prevalence and consequences 12. Platelet inhibitor treatment (no/acetylsalicylic acid
of delayed intracranial hemorrhage after head trauma (acetylsalicylic acid)/clopidogrel/ticagrelor/prasug-
with a particular focus on patients with antiplatelet or rel/dipyramidol/combinations)
anticoagulation therapy. 13. Other medication (yes/no)
14. New focal neurological deficits (yes/no)
Methods 15. Nausea (yes/no)
Data was retrieved through a review of the medi- 16. Vomiting (yes/no)
cal records of patients with isolated head trauma who 17. Amnesia, type, and duration (yes/no, antegrade/
presented to the ED at Helsingborg General Hospital retrograde, time hh:mm)
between January 1, 2020, and December 31, 2020. The 18. Loss of consciousness (yes/no)
ED serves a catchment population of 250,000 people 19. Peritraumatic seizure (yes/no)
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 3 of 8

20. Trauma mechanism diagnosed after 24 h would not have been diagnosed dur-
ing the mandated 24-h observation. Absence of TICH
One patient could be included several times in the was defined as “no TICH identified on any CT within
study if there was a new trauma. If a new trauma 30 days or/and patients discharged from ED without CT
occurred and an intracranial hemorrhage was found on prescribed”. The intervention was defined as neurosur-
a CT after this, it was recorded as a primary traumatic gical intervention or intensive care of any sort because
intracranial hemorrhage. of head trauma. Death due to TBI was defined as death
The primary outcome measure was the rate of delayed within 30 days from an index visit attributed to the head
intracranial hemorrhages. Secondary outcome measures injury. APT was defined as one or more antiplatelet ther-
were deaths and interventions such as intensive care or apies (acetylsalicylic acid, clopidogrel, ticagrelor, prasu-
neurosurgical operations because of the head trauma. grel, or dipyramidol) and no simultaneous ACT or low
Comorbidity and age were quantified with the vali- molecular weight heparin (LMWH) therapy. ACT was
dated age-adjusted Charlson Comorbidity Index (aa- defined as any oral pharmaceutical inhibiting coagulation
CCI) [21–24]. factors (Warfarin, Apixaban, Dabigatran, Rivaroxaban, or
All hospitals in the Skåne Region area share electronic Edoxaban) and no simultaneous APT or LMWH treat-
medical records. ED records, medical records from the ment. Patients who were prescribed both ACT and APT
ward (if admitted), and radiology reports were examined were analyzed separately and patients prescribed dou-
from the entire geographic region. Records up to 1 year ble APT were included in the APT cohort. Prothrombin
prior to the ED visit were searched for ongoing medi- international normalized ratio was not routinely inves-
cation and comorbidities that were omitted in the ED tigated in the head trauma patient category and could
records. No death records were reviewed which might therefore not be included in this study.
have led to patients that died at home or in nursing care Missing data was coded as such and analyzed as the
facilities being missed. Missing data from the physician’s absence of findings (e.g., if vomiting was not mentioned,
report was retrieved, when possible, through a review of the parameter was analyzed as “no episodes of vomit-
nurses’ notes and ambulance reports. Screening of medi- ing”). This was based on clinical judgment and experi-
cal records in Region Skåne within 6 months after index ence in that ED physicians produce pragmatic medical
visit was performed for follow-up. records and only mention positive findings. The param-
Data was collected by two reviewers. Reduction of eters we extracted are typically evaluated when assessing
information bias was attempted by adhering to guide- TBI patients and this way of dealing with missing data
lines for retrospective medical record reviews [25]. This was considered an acceptable risk of systematic informa-
entailed setting up and following an inclusive pro-forma tion bias. We have published previous TBI studies han-
document stating how data interpretation and coding dling missing data this way [1, 26, 27].
should be performed and formulating well-defined cri- Using Reaction Level Scale (RLS) is common practice
teria for inclusion and exclusion ahead of information in Sweden, and RLS was converted to GCS. Previous
collection. A Cohen’s kappa analysis of 100 randomized research has shown a good correlation between RLS1-2
medical records reviewed by two researchers was previ- and GCS14-15 but discrepancies between RLS3 and
ously published with good or very good agreement in all GCS13-8. To make study results internationally valid but
parameters but “new neurological deficits” and “LMWH- still scientifically correct, the level of consciousness was
treatment” [26]. only reported as GCS15-14 and GCS < 14 [28].

Data definitions and missing data Statistical analysis

Index-CT was defined as the CT performed at the first Data analysis was performed with SPSS version 27 for
ED visit after the head trauma. Patients were rescanned Mac. Histograms and Shapiro-Wilks formula were used
with further CTs as per clinical indication (e.g., a patient to explore data distribution. Non-parametric data was
was discharged and came back with worsened symp- presented with median, and 25th and 75th percentiles
toms or was admitted but did not recover as expected). (Q1 and Q3). The distribution of incidence of DICH was
TICH was defined as intracranial hemorrhage diagnosed quantified with a confidence interval (CI) according to
by index-CT. DICH was defined as intracranial hemor- the Poisson method. Differences in clinical traits between
rhage diagnosed after the initial ED index visit that did patients with TICH and DICH were tested with Fisher’s
not detect TICH (i.e., index-CT not detecting TICH or test when appropriate or Mann–Whitney U test when
patient discharged from ED without CT). A distinction appropriate. P < 0.05 was used for statistical significance.
between delayed intracranial hemorrhages diagnosed Because of the low number of DICHs in the present
within 24 h of trauma and 2–30 days was done as those material, a medical statistician was consulted. It was
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 4 of 8

decided that we would only present univariate statisti- Of the 1521 patients not diagnosed with TICH, 10
cal analyses, even if the conclusions that could be drawn (0.65%) patients were rescanned within 24 h, yielding 1
from this would be modest at best. DICH. Of the 1511 patients not diagnosed with TICH
or DICH within 24 h, 47 (3.1%) patients were rescanned
Results within 2–30 days, yielding another 3 DICHs. In total,
A total of 1627 patients with head trauma were included DICH was found in 4/1627 (0.25%, CI 0.06–0.64%) of
in the present study. See Fig. 1 for the inclusion process all included head trauma patients. Please see Table 1 for
and distribution of intracranial hemorrhages. the description of the anatomic locales of the different
An index-CT was performed on 1177 (72.3%) patients, intracranial hemorrhages.
and a total of 450 (27.7%) patients did not receive an The number of patients in the entire cohort with ACT
index-CT. TICH was found in 106/1627 (6.5%) patients. was 386 (23.7%), of which 108 had vitamin-K antagonist

Fig. 1 Inclusion process. This shows inclusion and exclusion criteria, the number of patients that were excluded in each step, and the number
of patients with different types of traumatic intracranial hemorrhage

Table 1 Localization of intracranial hemorrhages

Type of intracranial hemorrhage Delayed Delayed intracranial hemorrhage within 30 days (N = 3) Traumatic intracranial
intracranial hemorrhage (N = 106)
hemorrhage
within 24 h
(Na = 1)

Acute subdural hematoma 1 - 19

Subacute/chronic subdural hematoma - - 10
Subarachnoid hemorrhage - 1 15
Intracerebral hemorrhage - 1 8
Cerebral contusion - - 8
Mixed type hemorrhage - 1 27
Not clearly described in the radiology report - - 19
a
N number
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 5 of 8

treatment and 278 had DOAC treatment. Antiplatelet Discussion

therapy was found in 256 (15.7%) patients, of which 205 The present study was a retrospective medical records
had ASA treatment, 40 had other single APTs, and 11 review of adult patients seeking the ED with a head injury
had dual APT. Please see Table 2 for descriptive data and as the chief complaint. It included 1627 patients of which
Table 1 for data on anatomic localization of intracranial 0.25% (95% CI 0.06–0.64%) were diagnosed with DICH.
hemorrhages. This rate is at the low end of what has been reported in
The patient was diagnosed within 24 h and one of the other studies (0.2–1.5%) [9–13, 20]. The small number of
patients diagnosed within 2–30 days had APT. None of DICHs makes it difficult to draw anything but very cau-
the patients with DICH was prescribed ACT. Please see tious conclusions but some observations can be made.
Table 3 for a comparison of patients with TICH and The most important finding was the low prevalence of
DICH. The difference between ACT and APT in patients DICHs in combination with the absence of intensive care,
diagnosed with DICH and patients not diagnosed neurosurgical interventions, or deaths in patients with
with DICH was not statistically significant (p = 1.0 and DICH. Even though the cohort size of the present study
p = 0.578, respectively). was rather large, providing sound statistical evidence for
None of the DICH patients died, nor were any neuro- such rare events will require a larger sample size. Because
surgical interventions performed, and all but one of these of the design of the present study, it is impossible to know
patients were admitted at index visits. All patients with how many DICHs were missed, possibly explaining why
DICH had index CTs performed that did not show any the DICH rate is lower than some of the previous stud-
TICH. The patient that developed DICH and was initially ies. However, because the medical records were screened
discharged from the ED was not on either ACT or APT. for hospitalizations 6 months after the initial trauma,
we believe that we would have found most DICHs with
hospitalization as a consequence. Thus, if serious con-
Table 2 General patient characteristics sequences truly are rare, the in-hospital observation
despite a normal index-CT recommended by current
Variables All patients guidelines to exclude DICH in patients with ACT could
(n = 1627) be reconsidered. The best way to investigate this properly
General patient characteristics would be in a multi-center setting to achieve the sample
    Age (median (quartile 1, quartile 3)) years 72 (49, 84) size required. Additionally, the insipient chronic subdural
Gender hematomas that generally present a few weeks after the
    Female 822 (50.5%) trauma were not found in any of the patients with DICH.
Glasgow Coma Scale (GCS) An explanation for this might be that they usually pre-
    GCS 14–15 1558 (95.8%) sent with symptoms of impaired cerebral function and
    GCS < 14 15 (0.90%) that the initial head trauma is so mild that they never
Patient history seek medical attention because of it. Because the present
    Vomiting 114 (7.0%) study design only finds patients with “head trauma” as
    Loss of consciousness 452 (27.8%) the presenting complaint, these patients would be missed
    Amnesia 377 (23.2%) [29].
Charlson Comorbidity Index There was no significant difference in DICH/TICH
    Median (quartile 1, quartile 3) 3 (1, 5) rate between patients with ACT and APT in the present
    0–5 1271 (78.1%) study. However, the low prevalence of DICH precludes
    6–14 356 (21.9%) us from drawing any real conclusions from this find-
Clinical findings ing. Current TBI guidelines recommend more rigorous
    New neurological deficits at the index visit 101 (6.2%) work-up in patients with ACT, a statement that we can
    Peritraumatic seizures 27 (1.7%) neither corroborate nor invalidate based on our findings.
    Traumatic intracranial hemorrhage diagnosed at index- 106 (6.5%)
Nevertheless, only a few studies on this subject exist and
computerized tomography they have shown a similar risk for patients on ACT and
Clinical measures APT to develop DICH [13, 30]. To enhance the current
    Index head computerized tomography performed 1177 (72.3%) literature, even studies such as this with few DICHs are
    Admission to hospital 590 (36.3%) important to publish. The DICH rate of the present study
    ­Interventiona during index visit 7 (0.43%) did not allow for meaningful analysis of the risk con-
    Death due to head injury 10 (0.61%) ferred by subtypes of ACT or APT or any combination
    All-cause mortality 36 (2.2%) of those. However, Colombo et al. (2021) showed that the
a
Intensive care of any kind or neurosurgical operation
risk of DICH was elevated in patients with double APT
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 6 of 8

Table 3 Comparison of patients with traumatic intracranial hemorrhage diagnosed at index visit and patients with delayed
intracranial hemorrhage
Variables Patients with delayed Patients with traumatic intracranial P value
intracranial hemorrhage hemorrhage diagnosed at the index visit

(n = 4) (n = 106)
General patient characteristics
Age (median (quartile 1, quartile 3)) years 64 (60, 71) 79 (70, 87) 0.069a
Female 2 (50.0%) 48 (45.3%) 1.0b
Glasgow Coma Scale (GCS)
GCS 14–15 4 (100%) 102 (96.2%) 1.0a
GCS < 14 0 (0%) 4 (3.8%) 1.0a
Patient history
    Vomiting 1 (25%) 10 (9.4%) 0.348b
    Loss of consciousness 3 (75%) 17 (16.0%) 0.462b
    Amnesia 3 (75%) 33 (31.3%) 0.364b
Peritraumatic seizures 0 (0%) 1 (0.9%) 1.0b
Charlson Comorbidity Index
Median (quartile 1, quartile 3) 3 (1, 4) 4 (3, 6) 0.143b
Medications affecting coagulation
    Oral anticoagulation ­therapyc 0 (0%) 31 (29.2%) 0.575b
d
    Oral antiplatelet ­therapy 2 (50%) 28 (26.4%) 0.299b
Clinical findings
New neurological deficits 0 (0%) 18 (17.0%) 1.0b
Clinical measures
    Treatment at intensive care unit 0 (0%) 7 (6.6%) 1.0b
    Neurosurgical operation 0 (0%) 3 (2.8%) 1.0b
    Death due to intracranial hemorrhage 0 (0%) 7 (6.6%) 1.0b
a b c d
Fisher’s test. Mann-Whitney U test. Includes warfarin, apixaban, dabigatran, rivaroxaban, and edoxaban. Includes acetylsalicylic acid, clopidogrel, ticagrelor, and
dual antiplatelet therapy

but not monotherapy [31]. Results of this and other stud- Scandinavian 24-h observation after head trauma. How-
ies imply that patients on ACT and APT should probably ever, this finding mandates deliberation and this long
be considered to have a similar risk of developing DICH observation period has been disputed in the past [33–35].
[13, 30]. This is not the case in any of the current inter- Vershoof et al. (2018) argued that all significant DICHs
national guidelines [15–19]. It is feasible that managing in patients with ACT could be found on index-CT when
these patient cohorts in the same way would increase properly scrutinized and that only 0.2% of the patients
ICH detection. However, it is also conceivable that many developed DICHs that were found within 24 h [10]. It has
patients would need investigation in order to find very been argued that the constant improvements of CTs will
few DICHs. If the consequences of them are as mild as mean that more and more intracranial hemorrhages are
this and other studies imply, such management is debat- found at index-CT and that the rate of DICHs will con-
able [12, 13, 32]. Risk stratification based on, e.g., patient tinue to decrease [36]. Additionally, the rescanning of
history, trauma mechanism, signs, and symptoms would patients with small TICHs is an entirely different issue
be beneficial to identify the patients at risk. Thus far, only and should not be confused with the primary investiga-
one study offers a risk stratification tool for DICH and tion of patients in order to rule out DICH.
it has not been externally validated [9]. It found that old The low yield of mandatory CT scans and observation
age, craniofacial injury, neck injury, diabetes, and hyper- to find DICH carries substantial costs. It has been esti-
tension were associated with DICH. Further studies on mated to cost $1,000,000 to find one DICH [37]. Further-
risk factors for DICH would probably have the potential more, not all DICHs need intervention which entails that
to greatly reduce CT-rate in TBI patients [20]. the cost to find a DICH in need of intervention is even
Even if almost a fourth of the patients in the present higher. It can be difficult to use fiscal arguments against
study had ACT, the absence of DICH in this cohort diagnosing DICHs but this still needs to be taken into
is not enough evidence to discourage the mandatory account, at least by the governing bodies of health care.
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 7 of 8

Resources used to observe and rescan to rule out DICH Funding

Open access funding provided by Lund University. The study received no
can potentially delay care for other patients in the ED funding.
that have more urgent medical needs. Moreover, many
of the patients on APT or ACT are older and frail. It Availability of data and materials
Data will be made available upon request.
has been shown that even shorter terms of hospitaliza-
tion might have a negative impact on their life span [38].
Thus, avoiding unnecessary admissions in these individu- Declarations
als is important not only from an economic point of view. Ethics approval and consent to participate
The retrospective method is the most salient limitation The Swedish ethical review authority approved the study (202001109). The
study was performed in agreement with the ethical standards of the 1964 Hel-
of the current study. Information bias can occur when sinki Declarations and its later amendments. Informed consent was waived by
scrutinizing medical records and dealing with missing the ethical review authority due to its retrospective and non-invasive nature.
data. Notwithstanding efforts to counter this, only careful
Consent for publication
conclusions can be drawn from this study. Our pragmatic Consent for publication was also waived by the ethical review authority.
way of dealing with missing data was debated in the study
group prior to data collection and considered the best Competing interests
The authors declare that they have no competing interests.
solution. However, it carries the disadvantage of preclud-
ing reliability measurements such as confidence intervals.
The direction of bias can therefore not be quantified. Received: 30 March 2023 Accepted: 20 August 2023
Another source of bias is the patients’ compliance with
taking their prescribed medication affecting coagulation.
It is possible that this affects the results of this study but
the magnitude of that bias cannot be quantified with the
current study design. References
1. Vedin T, Svensson S, Edelhamre M, Karlsson M, Bergenheim M, Larsson
Construing “Head-CT not performed” as the absence PA. Management of mild traumatic brain injury-trauma energy level and
of intracranial hemorrhage can lead to missed intracra- medical history as possible predictors for intracranial hemorrhage. Eur J
nial hemorrhages. Nonetheless, because we searched the Trauma Emerg Surg. 2019;45:901–7.
2. Leach P, Childs C, Evans J, Johnston N, Protheroe R, King A. Transfer times
medical records for ED visits 6 months after the index for patients with extradural and subdural haematomas to neurosurgery
visit, it can be assumed that intracranial hemorrhages in Greater Manchester. Br J Neurosurg. 2007;21:11–5.
with severe consequences would have been found. How- 3. Nakahara S, Matsuoka T, Ueno M, Mizushima Y, Ichikawa M, Yokota J, et al.
Predictive factors for undertriage among severe blunt trauma patients:
ever, the true rate of DICHs cannot be found with this what enables them to slip through an established trauma triage protocol.
methodology. If patients die in their homes because of J Trauma. 2010;68:1044–51.
DICH, they are also missed. 4. Aygun N, Masaryk TJ. Diagnostic imaging for intracerebral hemorrhage.
Neurosurg Clin N Am. 2002;13(313–34):vi.
5. Brazinova A, Rehorcikova V, Taylor MS, Buckova V, Majdan M, Psota M,
Conclusion et al. Epidemiology of Traumatic Brain Injury in Europe: A Living System-
atic Review. J Neurotrauma. 2021;38:1411–40.
DICH after head trauma seems rare and none of these 6. Cooper PR. Delayed traumatic intracerebral hemorrhage. Neurosurg Clin
patients died or needed intensive care or neurosur- N Am. 1992;3:659–65.
gery. APT and ACT might confer similar risks of DICH. 7. Fakhry SM, Morse JL, Garland JM, Wilson NY, Shen Y, Wyse RJ, et al.
Antiplatelet and anticoagulant agents have minimal impact on traumatic
Because serious complications to DICH appear rare, brain injury incidence, surgery, and mortality in geriatric ground level
observing and/or rescanning all patients on ACT or APT falls: a multi-institutional analysis of 33,710 patients. J Trauma Acute Care
can be debated. Risk stratification of these patients might Surg. 2021;90:215–23.
8. Bauman ZM, Ruggero JM, Squindo S, McEachin C, Jaskot M, Ngo W, et al.
be a way to identify the patients at higher risk while safely Repeat head CT? Not necessary for patients with a negative initial head
reducing observation times and rescans. CT on anticoagulation or antiplatelet therapy suffering low-altitude falls.
Am Surg. 2017;83:429–35.
Acknowledgements 9. Kim B, Jeong H, Kim J, Kim T, Kim K, Lee H, et al. Incidence and risk factors
Not applicable. of delayed intracranial hemorrhage in the emergency department. Am J
Emerg Med. 2018;36:271–6.
Author contributions 10. Verschoof MA, Zuurbier CCM, de Beer F, Coutinho JM, Eggink EA, van Geel
Henrik Bergenfeldt contributed to the writing and critiquing manuscript and BM. Evaluation of the yield of 24-h close observation in patients with
data processing. Jakob Lundager Forberg contributed to the drafting and mild traumatic brain injury on anticoagulation therapy: a retrospective
critiquing manuscript. Ebba Anefjäll contributed to the data collection, data multicenter study and meta-analysis. J Neurol. 2018;265:315–21.
processing, and critiquing manuscript. Riikka Lehtinen contributed to the 11. Chauny JM, Marquis M, Bernard F, Williamson D, Albert M, Laroche M,
data collection, data processing, and critiquing manuscript. Tomas Vedin con- et al. Risk of delayed intracranial hemorrhage in anticoagulated patients
tributed to supervising the data collection, data processing, and manuscript with mild traumatic brain injury: systematic review and meta-analysis. J
writing. Emerg Med. 2016;51:519–28.
12. Hickey S, Hickman ZL, Conway J, Giwa A. The Effect of Direct Oral
Anti-Coagulants on Delayed Traumatic Intracranial Hemorrhage
Bergenfeldt et al. International Journal of Emergency Medicine (2023) 16:54 Page 8 of 8

After Mild Traumatic Brain Injury: A Systematic Review. J Emerg Med. 33. Menditto VG, Lucci M, Polonara S, Pomponio G, Gabrielli A. Management
2021;60:321–30. of minor head injury in patients receiving oral anticoagulant therapy: a
13. Huang GS, Dunham CM, Chance EA, Hileman BM. Detecting delayed prospective study of a 24-hour observation protocol. Ann Emerg Med.
intracranial hemorrhage with repeat head imaging in trauma patients on 2012;59:451–5.
antithrombotics with no hemorrhage on the initial image: a retrospective 34. Chenoweth JA, Gaona SD, Faul M, Holmes JF, Nishijima DK, Sacramento
chart review and meta-analysis. Am J Surg. 2020;220:55–61. CPRC. Incidence of delayed intracranial hemorrhage in older patients
14. Nishijima DK, Offerman SR, Ballard DW, Vinson DR, Chettipally UK, Rauch- after blunt head trauma. JAMA Surg. 2018;153:570–5.
werger AS, et al. Immediate and delayed traumatic intracranial hemor- 35. Eroglu SE, Onur O, Ozkaya S, Denızbasi A, Demır H, Ozpolat C. Analysis of
rhage in patients with head trauma and preinjury warfarin or clopidogrel repeated CT scan need in blunt head trauma. Emerg Med Int. 2013;2013:
use. Ann Emerg Med. 2012;59(460–468): e7. 916253.
15. Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PMC. Indica- 36. Booij R, Budde RPJ, Dijkshoorn ML, van Straten M. Technological develop-
tions for computed tomography in patients with minor head injury. N ments of X-ray computed tomography over half a century: User’s influ-
Engl J Med. 2000;343:100–5. ence on protocol optimization. Eur J Radiol. 2020;131: 109261.
16. Stiell IG, Wells GA, Vandemheen K, Clement C, Lesiuk H, Laupacis A, et al. 37. J. Li. Admit all anticoagulated head-injured patients? A million dollars
The Canadian CT Head Rule for patients with minor head injury. Lancet. versus your dime. You make the call. Ann Emerg Med. 2012;59(6):457–9.
2001;357:1391–6. 38. Keeble E, Roberts HC, Williams CD, Van Oppen J, Conroy SP. Outcomes of
17. Hodgkinson S, Pollit V, Sharpin C, Lecky F, National IFHACENICEGDG. Early hospital admissions among frail older people: a 2-year cohort study. Br J
management of head injury: summary of updated NICE guidance. BMJ. Gen Pract. 2019;69:e555–60.
2014;348:g104.
18. Barbosa RR, Jawa R, Watters JM, Knight JC, Kerwin AJ, Winston ES, et al.
Evaluation and management of mild traumatic brain injury: an Eastern Publisher’s Note
Association for the Surgery of Trauma practice management guideline. J Springer Nature remains neutral with regard to jurisdictional claims in pub-
Trauma Acute Care Surg. 2012;73:S307–14. lished maps and institutional affiliations.
19. Unden J, Ingebrigtsen T, Romner B. Scandinavian guidelines for initial
management of minimal, mild and moderate head injuries in adults: an
evidence and consensus-based update. BMC Med. 2013;11:50.
20. Mann N, Welch K, Martin A, Subichin M, Wietecha K, Birmingham LE,
et al. Delayed intracranial hemorrhage in elderly anticoagulated patients
sustaining a minor fall. BMC Emerg Med. 2018;18:27.
21. Yoon SJ, Kim EJ, Seo HJ, Oh IH. The association between Charlson Comor-
bidity Index and the medical care cost of cancer: a retrospective study.
Biomed Res Int. 2015;2015: 259341.
22. Sundararajan V, Henderson T, Perry C, Muggivan A, Quan H, Ghali WA.
New ICD-10 version of the Charlson comorbidity index predicted in-
hospital mortality. J Clin Epidemiol. 2004;57:1288–94.
23. Charlson ME, Charlson RE, Peterson JC, Marinopoulos SS, Briggs WM,
Hollenberg JP. The Charlson comorbidity index is adapted to predict
costs of chronic disease in primary care patients. J Clin Epidemiol.
2008;61:1234–40.
24. Fraccaro P, Kontopantelis E, Sperrin M, Peek N, Mallen C, Urban P, et al.
Predicting mortality from change-over-time in the Charlson Comorbidity
Index: a retrospective cohort study in a data-intensive UK health system.
Medicine (Baltimore). 2016;95: e4973.
25. Vassar M, Holzmann M. The retrospective chart review: important meth-
odological considerations. J Educ Eval Health Prof. 2013;10:12.
26. Vedin T, Karlsson M, Edelhamre M, Clausen L, Svensson S, Bergenheim
M et al. A proposed amendment to the current guidelines for mild
traumatic brain injury: reducing computerized tomographies while
maintaining safety. Eur J Trauma Emerg Surg. 2019;Epub Ahead of Print
27. Vedin T, Lundager Forberg J, Anefjäll E, Lehtinen R, Faisal M, Edelhamre M.
Antiplatelet therapy contributes to a higher risk of traumatic intracranial
hemorrhage compared to anticoagulation therapy in ground-level
falls: a single-center retrospective study. Eur J Trauma Emerg Surg.
2022;48:4909–17.
28. Johnstone AJ, Lohlun JC, Miller JD, McIntosh CA, Gregori A, Brown R, et al.
A comparison of the Glasgow coma scale and the Swedish reaction level
scale. Brain Inj. 1993;7:501–6.
Ready to submit your research ? Choose BMC and benefit from:
29. Yadav YR, Parihar V, Namdev H, Bajaj J. Chronic subdural hematoma.
Asian. J Neurosurg. 2016;11:330–42.
• fast, convenient online submission
30. Santing JAL, Lee YX, van der Naalt J, van den Brand CL, Jellema K.
Mild Traumatic Brain Injury in Elderly Patients Receiving Direct Oral • thorough peer review by experienced researchers in your field
Anticoagulants: A Systematic Review and Meta-Analysis. J Neurotrauma. • rapid publication on acceptance
2022;39:458–72.
• support for research data, including large and complex data types
31. Colombo G, Bonzi M, Fiorelli E, Jachetti A, Bozzano V, Casazza G, et al.
Incidence of delayed bleeding in patients on antiplatelet therapy after • gold Open Access which fosters wider collaboration and increased citations
mild traumatic brain injury: a systematic review and meta-analysis. Scand • maximum visibility for your research: over 100M website views per year
J Trauma Resusc Emerg Med. 2021;29:123.
32. Covino M, Manno A, Della Pepa GM, Piccioni A, Tullo G, Petrucci M, et al. At BMC, research is always in progress.
Delayed intracranial hemorrhage after mild traumatic brain injury in
patients on oral anticoagulants: is the juice worth the squeeze. Eur Rev Learn more biomedcentral.com/submissions
Med Pharmacol Sci. 2021;25:3066–73.