Systolic blood pressure below 110 mmHg is associated with increased mortality in penetrating major trauma patients: Multicentre cohort study

IntroductionNon-invasive systolic blood pressure (SBP) measurement is a commonly used triaging tool for trauma patients. A SBP of <90 mmHg has represented the threshold for hypotension for many years, but recent studies have suggested redefining hypotension at lower levels. We therefore examined the association between SBP and mortality in penetrating trauma patients.MethodsWe conducted a prospective cohort study in adult (≥16 years) penetrating trauma patients. Patients were admitted to hospitals belonging to the Trauma Audit and Research Network (TARN) between 2000 and 2009. The main outcome measure was the association between SBP and mortality at 30 days. Multivariate logistic regression models adjusted for the influence of age, gender, Injury Severity Score (ISS) and Glasgow Coma Score (GCS) on mortality were used.Results3444 patients with a median age of 30 years (IQR 22.5–41.4), SBP of 126 mmHg (IQR 107–142), ISS of 9 (IQR 9–14) and GCS of 15 (IQR 15–15), were analysed. Multivariable logistic regression analysis adjusted for age, gender, severity of injury and level of consciousness showed a cut-off for SBP at <110 mmHg, after which increased mortality was observed. Compared with the reference group with SBP 110–129 mmHg, mortality was doubled at SBP 90–109 mmHg, was four-fold higher at 70–89 mmHg and 10-fold higher at <70 mmHg. SBP values ≥150 mmHg were associated with decreased mortality.ConclusionWe recommend that penetrating trauma patients with a SBP < 110 mmHg are triaged to resuscitation areas within dedicated, appropriately specialised, high-level care trauma centres.