Purpose: Mortality in burn intensive care unit (ICU) has been decreasing and treatment appears to be changing. The aims of this study: (1) examine outcome in burn patients, (2) examine changes in ICU indication and (3) explore the influence of a changing case-mix. Methods: Retrospective study in patients admitted to ICU (1987–2016). Four groups were specified: major burns (≥15% TBSA), inhalation injury with small injury (<15% TBSA, inhalation injury), watchful waiting (<15% TBSA, without inhalation injury), tender loving care (patients withheld from treatment). Logistic regression was performed to evaluate the relation between case-mix and outcome. Results: Overall mortality decreased to 7%. Mortality of major burns decreased by 15%. The major burn group decreased by 36%. The inhalation injury and watchful waiting group increased by 9% and 21%. The percentage of ventilated patients increased by 14% in the major burn group. 40% of patients were ventilated in the watchful waiting group. Conclusions: After correction for case-mix, survival improved, mainly in the major burn group. Case-mix shifted towards inhalation injury and watchful waiting. Growth of the watchful waiting group is not necessarily harmful. However, the increase of mechanical ventilation could be. We suggest raising awareness for risks and consequences of mechanical ventilation.