Correlation of microalbuminuria and outcome in patients with extensive burns.

BACKGROUND Microalbuminuria, often referred to as the urinary albumin-creatinine ratio (ACR), is thought to be a reflection of increased capillary permeability associated with the systemic inflammatory response syndrome, and has been found to be predictive of outcome in several studies. Therefore, we explored the usefulness of ACR as a predictor of mortality, and whether there was a correlation between ACR and PaO2/ FIO2 ratios in patients with extensive burns. METHODS A retrospective observational study was carried out on all patients with extensive burns admitted to the burns intensive care unit. All adult patients with burns of at least 40%, or those with significant inhalational injury, were included. Exclusion criteria were paediatric patients or those with non-thermal processes such as Stevens-Johnson's syndrome. ACR was measured daily, and data including PaO2/ FIO2 ratios were collected. The outcome studied was mortality. RESULTS A total of 21 patients were studied, of which there were 7 mortalities. Data were analysed using SPSS Ver11. Patient characteristic data between survivors and mortalities were similar. We did not find any correlation between trends of ACR with PaO2/ FIO2 ratios. However, in non-survivors, there were two peaks in ACR, an early peak at days 8-9, and a later peak at day 32, whereas concentrations remained stable in survivors. CONCLUSION We conclude that while ACR is useful as a predictor of mortality and that mean ACR of more than 20 mg mmol(-1)is associated with poorer outcome, changes in ACR do not reflect changes in the patients' immediate clinical conditions.