No Cases of Delayed Intracranial Hemorrhage (d-ICH) Among Patients With Mild Traumatic Brain Injury (mTBI) on Oral Anticoagulation Therapy

Method This is a retrospective observational study investing the incidence of d-ICH at Sundsvall Regional Hospital. Data was collected from 2018-01-01 - 2020-05-30, and all data collection followed a predetermined protocol. Data was collected by two persons.

Starting from the hospital's radiology registry, all CT-scan referrals from emergency departments surgical section and acute surgical ward with a possible traumatic brain injury was read. Hereafter patients' journals were used to retrieve mechanism of injury, pre-injury medications, and arrival status.

TBI are typically classified after level of consciousness, internationally often measures in Glasgow Coma Scale (GCS) (3). At Sundsvall Regional Hospital, RLS (Reaction Level Scale) is more commonly used, hence it was used in data collection. However, in most cases patients' mental status was only commented as "unaffected" without any use of neither GCS nor RLS. In statistical analysis, we only recorded RLS where it was in clear print and choose not to translate "unaffected" into RLS 1. RLS 1 and GCS 15 are comparable, and GCS 14 and RLS2 are also comparable. mTBI is classified by Scandinavian Neurotrauma Committee's guidelines as a GCS 14 after head trauma, or GCS 15 after head trauma in combination with loss of consciousness, repeated vomiting, posttraumatic seizures, focal neurological deficits, signs of skull fracture, intracranial shunts, antithrombotic treatment, or antiplatelet treatment in combination with age over 65.

Inclusion criteria was mTBI and pre-injury anticoagulation or SGA therapy. In the initial data collection, all patients with mTBI regardless of antitrombotic therapy status were included for comparison for another study. Exclusion criteria was high energy trauma, age <18 years, concealed journals, spontaneous hemorrhage, RLS ≥3 (Figure 1). Due to the lack of control CT, patients on solely ASA or LMWH was also excluded due to former local clinical guidelines.

High energy trauma was excluded from this study, due to the heterogenous variety of injuries and often multiple organ injuries. High energy trauma was defined as any traffic accident or fall > 3 meters, or other traumas that required acute trauma care at the emergency trauma room.