Minimal volume for a fluid challenge in septic patients

• Research type

  Research Study

• Full title

  Study of changes on mean systemic filling pressure (Pmsf) and microcirculation after a fluid challenge in septic patients: looking for the minimal volume.

• IRAS ID

  158754

• Contact name

  Hollmann D Aya

• Contact email

  hollmann.aya@nhs.net

• Sponsor organisation

  St George's, University of London and St George's University Hospital NHS Foundation Trust

• Eudract number

  2012-004409-29

• Clinicaltrials.gov Identifier

  14/LO/1648, REC reference number

• Research summary

  The administration of fluids intravenously is the first step in the stabilization of patients in septic shock. It is important to give the right dose of fluids, enough to improve the function of the cardiovascular system but not too much to drown the cells in water. In order to know that, we use the “fluid challenge” which is the administration of a "small amount” of fluid in a short period of time in order to test the cardiovascular response to a dose of fluids. However, it is unclear how “small” this amount can be. The aim of this study is to find out the minimum volume required to perform an effective "fluid challenge". We hypothesise that the changes in the mean pressure in the cardiovascular system (so-called mean systemic filling pressure or Pmsf) during the administration of small amounts of fluid can be used to detect the minimum volume required to effectively test the cardiovascular system with a fluid challenge.
  On the other hand, microcirculation may remain impaired despite the stabilisation of the macrocirculation. The microcirculation can be much more dynamic than the macrocriculation, so it is essential to observe the changes of both over time. Patients admitted at our intensive care unit (ICU) due to sepsis can be included in this study. The sample will be devided in 4 groups according to the volume of the fluid challenge: 2 ml/kg, 3 ml/kg, 4ml/Kg and 5 ml/kg. We will meassure the Pmsf non-invasively using a pneumatic tourniquet inflated during one minute. Invasive arterial blood pressure will be observed during the inflation of the cuff in the arm to determine the Pmsf. The least significant change of Pmsf using this method is 14%. The minimal volume will be that one that achieve that change in Pmsf.

• REC name

  London - Queen Square Research Ethics Committee

• REC reference

  14/LO/1648

• Date of REC Opinion

  29 Sep 2014

• REC opinion

  Favourable Opinion