A randomised controlled trial of low-dose dopamine in postoperatively ventilated patients in the ICU: renal effects and the influence on outcome

Background

Despite the widespread use of low-dose dopamine in the ICU, there are only a few conflicting studies on its (protective) renal effects, some of them with contradictory results [1,2]. Consequently, we investigated renal effects as well as morbidity and mortality rates in patients being ventilated postoperatively in our ICU.

Patients and methods

Three hundred and forty-seven urology and abdominal surgery patients were randomised into two groups: A) no dopamine (n = 174) and B) dopamine at 2 µg/kg/min for the duration of intensive care treatment (n = 173). Creatinine and urea were determined at admission in our ICU (day 1) and the next day at 7 a.m. (day 2) together with hourly diuresis. Complications, length of stay and outcome from ICU treatment were recorded. The study was approved by the local Ethics Committee and informed consent was obtained from the patient prior to admission for surgery. Paired and unpaired Student's t-tests, Fisher's Exact Test and Chi square tests were used for statistical analysis.

Results

The individual differences for creatinine and urea (day 2-day 1) (mean ± S.D.) are shown in the table: (Complications: Group A) 38 pts. (22%), B) 38 pts. (21.8%) [n.s.]).

Conclusion

In our study, dopamine caused a significant diuresis without significant changes in creatinine or urea levels. Low-dose dopamine was not associated with a higher incidence of adverse cardio-circulatory reactions. We observed no protective effect on the incidence of ARF and our results indicate that low-dose dopamine may be associated with unfavourable outcomes, in particular higher mortality.

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