APACHE II score may predict mortality in burns patients

Introduction

The APACHE II scoring system has not been validated in burn injuries. The validation studies were performed in the general and cardiac ICUs of teaching hospitals in the USA; units that did not admit burn injuries [1]. We correlated known predictors of mortality in burns (age, percentage total burn surface area (%TBSA), inhalation injury) [2, 3] with mortality data in our burns cohort. This was repeated for the APACHE II score to investigate its predictive value.

Methods

We identified all patients with burns admitted to our ICU, linked to the South East Scotland Regional Burns Unit, from 1995 to 2005. Demographic data and APACHE II score at 24 hours were found on the ICU database. The case notes for each patient were reviewed to verify the %TBSA and survival.

Results

The cohort comprised 100 patients: 75% male. The age range was 14 to 87 years (mean 45.2; median 45). Injury severity was assessed by %TBSA: range 0 to 99% (mean 23.8%, median 16%, IQR = 8.6 to 30%). Zero %TBSA is inhalation injury only. APACHE II scores ranged from 7 to 42 (mean 15.9, median 15, IQR = 10 to 19.5). The apparent fall in mortality at scores 27 to 31 is due to low numbers (n = 3) in this group. Both the %TBSA and APACHE II score correlate with increasing mortality (Figure 1). Stepwise logistic regression analysis was performed: %TBSA and APACHE II score both behaved as independent predictors of mortality (P < 0.0001), as did age (P = 0.002). This cohort behaves as other published data [2, 3].

Figure 1

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Conclusion

Scoring systems with applicability to all critically ill patients provide a standardised objective assessment tool allowing comparison between groups, and can inform clinical decision-making. The strong correlation shown between APACHE II score and mortality provides evidence for the utility of APACHE II scoring in critically ill patients with burn injuries.