Dynamic neuroendocrine changes in critically ill patients with polytrauma

Acute multiple-trauma induces activation of neuroendocrine system. Nonthyroidal illness syndrome (NTIS) is considered to be associated with adverse outcome in intensive care unit (ICU) patients. This study was aimed to assess dynamic changes of neuroendocrine hormones in patients with polytrauma and their association with the polytrauma score (PTS).

Blood samples from 24 critically ill patients with polytrauma were obtained on 1st, 2nd, 3rd and 7th day after admission to ICU for analysis of thyroid-stimulating hormone (TSH), total triiodothyronine (T3); free triiodothyronine (fT3), total thyroxine (T4), free thyroxine (fT4), growth hormone (GH), prolactin (PRL) and procalcitonin levels.

Acute Physiology and Chronic Health Evaluation (APACHE) II score was 16±5 points on average at the admission to ICU. All patients had normal baseline TSH, T4, fT4, but low T3, and fT3 levels were found in 20% and 33% ICU patients, respectively. On the 7th day after admission to ICU TSH had tendency to increase (p=0.07) and fT4 significantly decreased (p=0.03). The PRL level significantly increased on the 3rd day after admission as compared to 1st day (p=0.04). PTS positively correlated with fT3 (r=0.582, p=0.004) and negatively with fT4 (r=-0.422, p=0.04) at the 1st day in ICU.

Critical illness in patients with polytrauma leaded to trauma severity-dependent alterations of the thyroid axis response early after injury. Our findings suggest that detection of dynamic hormonal response is more appropriate than single measurement. However supplemental therapy for NTIS should be used after more detailed studies are completed.