The Effect of Increasing the Mean Arterial Pressure on the Microcirculation and the Prognosis of Patients With Septic Shock

Background： The mean arterial pressure（ MAP） is a key pressure index to improve tissue perfusion. At present, there are no surprising results of large-scale clinical studies on sublingual microcirculation. The changes of sublingual microcirculation were more severe in septic shock non-survivors than survivors. Purpose： This study is mean to increase the MAP in septic shock patients whether with chronic hypertension or not, so as to observe the change of the microcirculation and prognosis. Method： This is a single-center, randomized, prospective cohort study. Eligible patients will be allocated into chronic hypertension or denying chronic hypertension group. These patients will be treat with vasopressors to maintain MAP at 90±5 mmHg and 70±5 mmHg. Outcome： The 28-day all-cause mortality, the 90-day all-cause mortality, the 28-day without organ dysfunction days, the Changes of sublingual microcirculation, SOFA， APACHE-Ⅱ score Will be recorded.