Interventional study comparing effect of two regimes of fluid challenge in patients with sepsis and in patients undergoing elective major surgery on glycocalyx by using perfused Boundary Region in sublingual microcirculation.

Effect of two regimes of fluid challenge on GCX in patients with sepsis and during elective surgery under general anesthesia.

Hypothesis to be tested: Administration of 500 ml of balanced solution as a bolus impairs GCX more than prolonged administration.

The aim of the study: Comparison of two regimes of fluid challenge in patients with sepsis and in patients undergoing elective major surgery.

Type of the study: Open, randomized, interventional.

Subjects:

Part A: Patients with sepsis within 48 hours before admission to ICU requiring fluid challenge based on clinical or echocardiographic assessment.

Part B: Patients during major elective surgery requiring fluid challenge based on clinical or echocardiographic assessment.

Sample size calculation (based on expected difference in PRB, alpha error I =0,05 and study power = 0,99) = 52 patients. Investigators plan enrolment of 60 patients for each part, totally 120 patients.

Intervention:

• 500 ml of balanced crystalloid solution within 5 minutes (group "fast")
• 500 ml of balanced crystalloid solution within 30 minutes (group "slow") Data to be recorded and analysed: Demographics, severity score, fluid response assessment, sublingual microcirculation by SDF imaging will be recorded at time points: baseline, after intervention, after 60 minutes, after 120 minutes, plasma syndecan-1 will be analysed before intervention and 120 minutes thereafter, microcirculatory data and Perfused Boundary Region.

Inclusion Criteria:

arm A: age over 18, diagnosis sepsis, fluid bolus administration indicated, arm B: age 18-70, ASA status I-III, major surgery

Exclusion Criteria:

none.