Independent Predictors of Mortality in Polytrauma Patients: a Prospective, Observational, Longitudinal Study

The study protocol was approved by the Institutional Medical Ethics Committee (CAPPesq 1081/09) and received financial support from the São Paulo State Research Foundation (Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP) under no. 2010/03315-4.

At the end of data prospecting, 334 patients with severe trauma (Injury Severity Score, ISS, >15), assisted by the rescue system and taken to HCFMUSP-Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo- (by land and helicopter) were included in the study. This screening strategy included trauma patients with severe confirmed bleeding, patients with severe traumatic brain injury (TBI) and patients facing high-energy trauma (a marked characteristic of this trauma center). Patients under 18 years of age were excluded ( Figure 1).

In total, 78 patients were excluded because they did not fit the above criteria, leaving 256 patients for analysis. Of this total, 34 patients died before arriving at the emergency room, and 22 were removed from the analysis due to incomplete data, not signing the informed consent form or due to any situation in which the data collection could compromise victim care(care Figure(Figure 1).

All patients had data recorded at the following times: 1, at the trauma scene; 2, in the emergency room; 3, at 3 hours after hospital admission; and 4, at 24 hours after hospitalization.

Data regarding gender, age, trauma and trauma mechanism, medical procedures performed at all stages, time until arrival at the hospital and comorbidities were recorded. The clinical data collected were as follows: systolic blood pressure (SBP); diastolic blood pressure (DBP); heart rate (HR); respiratory rate (RR); arterial hemoglobin oxygen saturation (SAT); Glasgow Coma Scale (GCS) score; and pupil pattern. The following laboratory data were collected through peripheral venipuncture at the hospital stages: pH(hydrogenic potential); base excess (BE); bicarbonate (BIC); partial oxygen pressure (pO2); partial carbon dioxide pressure (pCO2); arterial hemoglobin oxygen saturation; lactate; sodium (Na+); potassium (K+); ionized calcium (Ca2+); glucose; hemoglobin (Hb); hematocrit (Ht); serum creatine phosphokinase (CPK); platelets and leukocytes. Data regarding volume expansion [crystalloids (CRYSTAL), colloids (COLO)], diuresis and water balance were also collected. The use of blood products [packed red blood cells (PRBC), fresh frozen plasma (FFP), platelet concentrates (PLAT), cryoprecipitate concentrates (concentrates (CRYO)] was computed, and the use of vasoactive drugs (VAD) was scored at the respective times. Patient follow-up was conducted at the intensive care unit (ICU), and time of ICU stay (days in the ICU), days under mechanic ventilation (days under MV), the presence or absence of sepsis, coagulopathy and acute renal failure (ARF) were recorded.