Mortality in burn patients can be predicted by three risk factors: age ≥ 60 years, total burned surface area (TBSA) ≥ 40%, and presence of inhalation injury. According to the formula of Ryan , patients with zero, one, two or three of the above risk factors, have a mortality rate of 0.3%, 3%, 33% and 90%.
Evaluation of the predictive value of the risk factors as proposed by Ryan in Belgian burn patients.
We retrospectively analysed all patients admitted between 1999 and 2004 to the six Belgian burn units.
During the study period 6227 patients were admitted. The annual incidence rate of severe burn injuries admitted to the burn unit was 10.11 per 100,000 inhabitants. The median age was 34 years (IQR: 16.0–48.0). The median TBSA was 5% (IQR: 2.0–15.0). Inhalation injury was present in 574 patients (9.2%).
Overall mortality was 4.6%. When zero, one, two or three risk factors were present, mortality was respectively 0.5%, 9%, 43% and 87%. Table 1 presents outcome for the different combinations of risk factors.
The incidence rate of severe burn injury in Belgium was low. The risk factors proposed by Ryan were also indicative for outcome. However, some of these three risk factors were more important for outcome than others. Also, the combination of different risk factors influenced outcome considerably.