Development of a scoring system based on conventional parameters to assess polytrauma patients: PolyTrauma Grading Score (PTGS)

Background The impact of conventional laboratory data to identify polytrauma patients at risk of complications is established. However, it has not been assessed in terms of prognostic accuracy for systemic complications (ARDS, organ failure). We therefore assessed the most predictive parameters for systemic complications and developed a scoring system for early grading of polytrauma patients. Methods A population based trauma registry was used. Inclusion criteria: age >16 years, Abbreviated Injury Score (AIS) of the abdomen or chest ≥3 points and treatment in an intensive care unit, or Injury Severity Score (ISS) ≥16 points. The primary endpoint was hospital mortality. Patients were graded according their risk of death: low risk of death (5-14% mortality), intermediate risk patients (15-39% mortality) and high risk (>40%). Routine clinical and laboratory parameters on admission were assessed to determine their specific relevance to describe the risk profile of the patient. Based on these data, a scoring system for the description of the clinical status was developed. Statistical analysis included uniand multivariate analysis. Results 11.436 patients were included, the mean ISS was 22.7 ± 11.2 points, 73% were male, and 95.6% had blunt injuries. The most sensitive parameters were found to be the following ones: systolic blood pressure, INR, thrombocytes, base deficit, NISS, packed red blood cells administered. The multivariate analysis revealed the following threshold levels: BP 76-90 mmHg: r = 0.249, OR 1.283: Base deficit 8-10 r = 0.474, OR 1.606; INR 1.4-2 r = 0.160, OR 1.174; NISS 35-39 r = 0.9, OR 2.46; pBRC 3-14: r = 0.671, OR 1.957. The following ranges of score values were found to be associated with different patient status: <6 points: stable patients; 6-11 points: borderline condition; >11 points: unstable patients. When using this score, 80.6% were stable, 14.6% in a borderline condition and 4.8% unstable. Conclusion We developed a scoring system to discriminate polytrauma patients on admission that are at risk of systemic complications. Systolic blood pressure, INR, thrombocytes, base deficit, NISS, packed red blood cells administered are able to provide a prognosis of patients at risk of posttraumatic complications. Further prospective studies should be performed to verify this new scoring system.