Changes in the outcomes of severe trauma patients from 15-year experience in a Western European trauma ICU of Emilia Romagna region (1996-2010). A population cross-sectional survey study

Abstract

Background: Our experience in trauma center management increased over time and improved with development of better logistics, optimization of structural and technical resources. In addition recent Government policy in safety regulations for road traffic accident (RTA) prevention, such compulsory helmet use (2000) and seatbelt restraint (2003) were issued with aim of decreasing mortality rate for trauma.

Introduction: The evaluation of their influence on mortality during the last 15 years can lead to further improvements.

Methods: In our level I trauma center, 60,247 trauma admissions have been recorded between 1996 and 2010, with 2183 deaths (overall mortality 3.6 %). A total of 2,935 trauma patients with ISS >16 have been admitted to Trauma ICU and recorded in a prospectively collected database (1996-2010). Blunt trauma occurred in 97.1 % of the cases, whilst only 2.5 % were penetrating. A retrospective review of the outcomes was carried out, including mortality, cause of death, morbidity and length of stay (LOS) in the intensive care unit (ICU), with stratification of the outcome changes through the years. Age, sex, mechanism, glasgow coma scale (GCS), systolic blood pressure (SBP), respiratory rate (RR), revised trauma score (RTS), injury severity score (ISS), pH, base excess (BE), as well as therapeutic interventions (i.e., angioembolization and number of blood units transfused in the first 24 h), were included in univariate and multivariate analyses by logistic regression of mortality predictive value.

Results: Overall mortality through the whole period was 17.2 %, and major respiratory morbidity in the ICU was 23.3 %. A significant increase of trauma admissions has been observed (before and after 2001, p < 0.01). Mean GCS (10.2) increased during the period (test trend p < 0.05). Mean age, ISS (24.83) and mechanism did not change significantly, whereas mortality rate decreased showing two marked drops, from 25.8 % in 1996, to 18.3 % in 2000 and again down to 10.3 % in 2004 (test trend p < 0.01). Traumatic brain injury (TBI) accounted for 58.4 % of the causes of death; hemorrhagic shock was the death cause in 28.4 % and multiple organ failure (MOF)/sepsis in 13.2 % of the patients. However, the distribution of causes of death changed during the period showing a reduction of TBI-related and increase of MOF/sepsis (CTR test trend p < 0.05). Significant predictors of mortality in the whole group were year of admission (p < 0.05), age, hemorrhagic shock and SBP at admission, ISS and GCS, pH and BE (all p < 0.01). In the subgroup of patients that underwent emergency surgery, the same factors confirmed their prognostic value and remained significant as well as the adjunctive parameter of total amount of blood units transfused (p < 0.05). Surgical time (mean 71 min) showed a significant trend towards reduction but did not show significant association with mortality (p = 0.06).

Conclusion: Mortality of severe trauma decreased significantly during the last 15 years as well as mean GCS improved whereas mean ISS remained stable. The new safety regulations positively influenced incidence and severity of TBI and seemed to improve the outcomes. ISS seems to be a better predictor of outcome than RTS.