The effect of N-acetylcysteine on total serum anti-oxidant potential and urinary albumin excretion in critically ill patients.

OBJECTIVE

To investigate the effects of N-acetylcysteine (NAC) when given as an early treatment to critically ill patients on the serum total anti-oxidant potential (TAP) and urine micro-albumin:creatinine (M:Cr) ratio.

DESIGN

Prospective, placebo controlled double blinded clinical trial.

SETTING

General intensive care unit in a teaching hospital.

PATIENTS

Sixty critically ill patients were recruited but ten were withdrawn due to less than 48 h of ICU stay.

INTERVENTIONS

After envelope randomisation, patients received either NAC (n = 23): a bolus of 150 mg/kg in 250 ml of 5% dextrose followed by a continuous infusion of 12 mg/kg per h in 500 ml of 5% dextrose over 24 h or, as controls (n = 27), the equal volume of placebo. Treatment lasted for a minimum of 3, up to a maximum of 5, days. Blood and urine samples were collected on admission (0 h) and then 6 hourly up 18 h.

MEASUREMENTS AND RESULTS

There was no significant difference between NAC and placebo groups regarding the required length of inotropic support, mechanical ventilation and ICU stay. There was no significant difference in TAP or M:Cr ratio over 18 h or between the groups.

CONCLUSIONS

Our results suggest that NAC had no significant effects on the progress of the TAP and the urinary albumin excretion in our patients, which may suggest that NAC at the given dose has no clinical relevance as an early treatment in the critically ill.