A Prospective Study of The Complement Depletion in Patients With Severe Abdominal Sepsis
Condition: Severe Sepsis; Pancreatitis; Abdominal Abscess; Appendicitis; Digestive System Fistula
MeSH terms: Sepsis; Toxemia; Appendicitis; Intraabdominal Infections; Abdominal Abscess; Pancreatitis; Digestive System Fistula; Fistula
Study type: Interventional

Summary: 
      The role of complement system in bridging innate and adaptive immunity has been confirmed in
      various invasive pathogens. The aim of this study is to investigate the alteration of
      complement C3 in patients with severe abdominal sepsis and evaluate the role of complement C3
      depletion in prognosis of such patients. The relationship between complement C3 depletion and
      adaptive immunity is studied meanwhile.
    

Detailed description: 
      Severe abdominal sepsis remains a significant cause of death in patients undergoing
      intra-abdominal infection, in despite of recent declines in overall mortality. There is a
      abundant evidence to suggest complement activation during sepsis. While there is great
      interest in complement by-products in human sepsis, few studies focus on the persistent
      consumption of complement components and its role in prognosis of sepsis. Complement C3 is
      indispensable community pathway for complement activation. In a way, the alteration of C3
      levels can affect the whole status of complement biological functions.

      In clinical practice, the severe abdominal sepsis would develop compromised immune function
      if the intra-abdominal infection is not well controlled. The down-regulated T- and B-cell
      immune responses to sepsis are correlated to the decreased immune defense. To our knowledge,
      there are few human data that have investigated the relationship between complement depletion
      and adaptive immunity in severe abdominal sepsis. The investigators hypothesize that the
      complement C3 depletion during sepsis has a stronger association with the down-regulated
      adaptive immunity and can be regarded as a essential risk factor to predict the prognosis of
      such critical illness.

      The purpose of this prospective study is two-fold. First, the investigators observe, in a
      cohort of patients with severe abdominal sepsis, the levels of complement components and
      percentages of T cell subsets after admission to evaluate the relationship between complement
      system and adaptive immunity. Second, the investigators also evaluate the application of the
      C3 related-indexes (C3, C3a, Factor H, DAF, etc.) to patients undergoing severe abdominal
      sepsis and to develop an alternative model to predict its prognosis.
    

Intervention name(s): Norepinephrine; Open abdomen; enteral nutrition; parenteral nutrition
Intervention type(s): Drug; Procedure; Other; Other
Intervention description(s): Intravenously, 10 ug/min, 24 hours; IAH >=20 mmHg, and ACS emerged, such as low urine and decreased FiO2 quickly.; 500-1500 kcal/day; Nasogastric tube feeding;; 3000 mL parenteral nutrition fluid, intravenously.
Other intervention name(s): Peptison (SP; Nutricia, Shanghai, China); Made by our hospital.
Intervention MeSH terms: Norepinephrine
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Screening