A total of 5,736 trauma patients were admitted to the Chungbuk National University Hospital between January 2016 and June 2019. Out of these patients 1,388 were admitted to the ICU and 478 were older than 65 years (35.7%). Twelve patients were excluded because they were transferred to other facilities. Therefore, the total number of patients enrolled in this study was 466. The medicated group consisted of 142 (30%) patients that were taking preinjury anticoagulant or antiplatelet agents including aspirin (72 patients), clopidogrel (25 patients), warfarin (9 patients), NOAC (12 patients), or a combination of these medications (24 patients). Therefore, the non-medicated group was made up of 324 (70%) patients (Fig, 1). The proportion of patients older than 65 years among all the trauma patients admitted to hospital from January 2016 to June 2019 increased gradually from 34% to 38% (Fig. 2).
The average age of the participants was 75.7 years (standard deviation [SD], 6.88 years), 311 were male and 155 were female. The past medical history of the patients were as follows: 71 had cardiovascular disease, 27 had cerebrovascular disease, 223 had hypertension, and 114 had diabetes. The most common mechanism of injury, making up 23% of all cases, was pedestrian traffic accidents, followed by motorcycle accidents (18.2%), falls (16.3%), motor vehicle accidents (13.7%), slipping down (13.1%), other (10.3%), and bicycle accidents (5.4%). The ISSs ranged between 4 and 75 (average 19.58) (Table 1).
Comparison of participant groups
The average age of the patients in the medicated group was 76.6 years (SD, 6.87 years), older than the average age of the patients in the non-medicated group, which was 75.3 years (SD, 6.85 years), but without statistical significance (p = 0.06). The medicated group were more likely to have cardiovascular disease than the non-medicated group (21.8% vs. 12.3%, respectively, p = 0.01), and cerebrovascular disease (11.3% vs 3.4%, respectively, p = 0.02). The medicated group's average ISS was 18.19, lower than the 20.19 of the non-medicated group (p = 0.03). The average Glasgow coma score (GCS) of the medicated group was 12.19, while that of the non-medicated group was 11.46 (p = 0.09) (Table 1). In total 96 patients died during treatment (20.6%), while 239 (51.3%) underwent operations, and 101 (21.7%) received angioembolisation. Red blood cell transfusions were received by 197 patients, plasma by 137, and platelets by 89. Of the 225 patients (48.3%) who required mechanical ventilation, 53 needed long-term ventilation and received a tracheostomy. Complications occurred in 164 patients, with pneumonia being the most common developing in 17.2% (Table 2).
Requirements for transfusion
We compared the required amount of blood transfusions within 4 hours of hospital arrival, and within the next 20 hours between the two groups. There was a statistically significant difference in the amount of blood transfused within 4 hours between the medicated and non-medicated groups, 0.89 units and 1.43 units, respectively (p = 0.03), while no differences were demonstrated for any other types of transfusion (Table 3). A multiple linear regression analysis of ISS and preinjury antiplatelet or anticoagulant medications showed no relationship with the transfusion amount of red blood cells, p = 0.48; plasma, p = 0.35; or platelets, p = 0.59. However, a positive relationship was observed between the higher ISSs and the need for more transfusions (p=0.00) (Table 4). Massive transfusions were given to 30 patients, but no relationship with preinjury anticoagulant or antiplatelet medications was detected (Table 5). The average ISS was higher (33.43) in the massive transfusion group (p=0.00). There was also a statistically significant difference in the GCS and initial blood examinations. The multivariate analysis demonstrated that patients had an increased risk of needing a massive transfusion if they had a higher ISS and a high initial INR and aPTT. Within the massive transfusion group, there was no significant statistical difference in the amount of red blood cells (p = 0.61), plasma (p = 0.23), or platelets (p = 0.55) transfused between the medicated group and the non-medicated group (Table 6).
The patients in the medicated group underwent more operations than those in the non-medicated group (51.9% vs. 50.0%, respectively, p = 0.76), and more angioembolisations (24.1% vs. 16.2%, respectively, p = 0.67), but without statistical significance. There were no significant statistical differences in the number of days spent in ICU (9.50 vs. 7.98, respectively, p = 0.24), or days on mechanical ventilation (6.08 vs. 6.34, respectively, p = 0.85) (Table 7). The complication rate was higher in the medicated group than the non-medicated group (47.9% vs. 29.6%, respectively, p = 0.001) with an odds ratio of 2.18 (95% confidence interval [CI]: 1.453 -3.277). Bleeding was more frequent in the medicated group (17.6% vs. 2.8%, respectively, p = 0.001), odds ratio of 7.48 (95% CI: 3.391-16.493), as was pneumonia (24.4% vs. 14.2%, respectively, p = 0.01), odds ratio of 1.90 (95% CI: 1.159-3.124). A multivariate analysis showed that patients taking preinjury medications were at a 1.79-fold risk of suffering 2 or more complications.(p = 0.04) (Table 8). The mortality rate was higher in the medicated group than the non-medicated group (22.2% vs. 16.9%, respectively, p = 0.21) but without statistical significance.