Treatment of dopamine-dependent shock with triiodothyronine

Abstract

At the present time dopamine is the most frequently used treatment in patients with septic shock. The effects of dopamine are mediated by alpha-, beta- and dopaminergic receptors. It has been suggested that these receptors are controlled by triiodothyronine (T₃). In acute septic shock circulating T₃-concentrations are decreased. We have, therefore, treated in a preliminary study 11 such patients with T₃-replacement by continous infusion of T₃ (100–200 μg/24h). Dopamine dependence was terminated. In all patients there was an increase of arterial blood pressure (BP) within 24 hrs (systolic BP rose by 34 4.2 mmHg, diastolic BP by 14.0 8.2 mmHg, resulting in an increase of the mean BP by 25 6.1 (SEM) mm Hg). The pulse rate was not influenced suggesting an effect on minute volume. A hypothesis is offered which explains the T₃-effects as a results of its decarboxylation to a dopaminergic iodothyronine which is disturbed during the “low T₃-syndrome”.