Pilot Phase II Study: Hemodynamic Tolerance and Anti-inflammatory Effects of Esmolol During the Treatment of Septic Shock

During septic shock, the consequences of treatment by a β1-blocker on inflammation and cardiovascular variability are unknown. The use of esmolol should have positive effects on inflammation and hemodynamic tolerance. These effects are probably dose-dependent.

The study will enroll adult patients hospitalized in ICU, for severe septic shock requiring treatment by a vasopressor.

A total of 45 patients will be included. Among these 45 patients, 15 patients will be randomized in the control group. 30 patients will be randomized to Esmolol with the objective to decrease heart rate by 10% (Group G10, n=15) or 20% (Group G20, n=15). Esmolol will be administered for 24 hours.

This multicenter study will be performed in 3 investigation sites.

The following parameters will be evaluated at different moments during the 28 days follow up of each patient, mainly:

* Origin of sepsis, SOFA score. * Hemodynamic parameters will be continuously recorded for the 24 hours of experimental period. * Cardiovascular variability (arterial pressure and heart rate) will be recorded for 24 hours. * 3 echocardiograms at H0, H12 and H24 will be performed. * Biological parameters will be sampled at H0, H6, H12 and H24: They include standard biological parameters (Urea, Creatinin, Bilirubin,……) and specific parameters (catecholamines, vasopressin, insulin, cortisol, proinflammatory cytokines and anti-inflammatory cytokines. Dosages will be performed only at H0, H12 and H24 in order to study:

* The expression of adrenergic receptors and their genetic polymorphisms on circulating immune cells. * The Th1/Th2 balance in immune cells.

Each patient will be followed-up for 28 days.

The variation of MAP and of cardiac output induced by esmolol should not exceed 15% of baseline values. If the variation is more important esmolol administration will be stopped and the hemodynamical tolerance will be defined as poor.