Objective: To evaluate the effects of hydrocortisone on microcirculatory blood flow alterations in patients with septic shock.
Design: Prospective, open-label study.
Setting: A 31-bed, medico-surgical intensive care unit of a university hospital.
Patients: Twenty patients with septic shock.
Interventions: Intravenous hydrocortisone (50 mg/6 hr).
Measurements and main results: An orthogonal polarization spectral device (Cytoscan ARII, Cytometrics; Philadelphia, PA) was used to investigate the sublingual microcirculation in 20 patients who received so-called "stress doses" of hydrocortisone as part of their management for septic shock. Hemodynamic measurements and orthogonal polarization spectral images were obtained before administration of the first dose (50 mg) of hydrocortisone and 1, 2, 4, and 24 hours later. Measurements were also made before an adrenocorticotropic hormone (ACTH) test, whenever performed. Global hemodynamic variables were similar at all study time points. Microcirculatory variables improved slightly already at 1 hour after the start of hydrocortisone administration. In particular, perfused vessel density increased from 5.7 (4.8-6.4) to 7.2 (6.5-9.0)n/mm, p < 0.01, which was due to combined increases in small vessel density from 5.2 (4.6-6.2) to 6.0 (5.1-7.5)n/mm, p < 0.01, and in the proportion of perfused vessels from 82.1 (68.7-88.0) to 89.2 (83.4-92.6)%, p < 0.01. There were no differences in microcirculatory variables during hydrocortisone administration between ACTH test responders and nonresponders.
Conclusions: The administration of moderate doses of hydrocortisone in septic shock results in a modest but consistent improvement in capillary perfusion, independent of the response to the ACTH test. The mechanisms underlying this effect need to be elucidated.