Sepsis is a high morbidity and mortality in critical care unit. Clinically, we found that secondary thrombocytopenia was common in the patients with septic shock, and the incidence can be as high as 55%. Moreover, many studies have shown that thrombocytopenia is an early prognostic marker in septic shock and an independent risk factor for the mortality of septic shock. And then, it has been reported that early recovery from thrombocytopenia helps to prevent the coagulopathy and decreases the mortality. At present, the managements of sepsis-induced thrombocytopenia are mainly platelet transfusion and platelet-increased drugs. Because of source scarcity, transfusion-related infectious and immunological complications, platelet transfusion is limited in the clinical treatment. So, the use of platelet-increased drugs for replacement therapy becomes an inevitable trend. The primary purpose of this study is to explore the effect of platelet-increased drugs(rhTPO) on the 28-day mortality among septic shock patients with thrombocytopenia.