Restrictive Versus Conservative Fluid Therapy in Colorectal Surgery
Condition: Fluid Therapy
Study type: Interventional

Summary: 
      Fluid administration during and after surgery is an essential part of postoperative care to
      maintain the patients' fluid and biochemical balance. Abdominal surgical procedures are
      associated with dehydration from preoperative fasting, bowel preparation, and intra- and
      postoperative fluid and electrolyte loss. So, perioperative fluid management has been a topic
      of much debate over years and has intensified especially over the past several years.
    

Detailed description: 
      The controversies include the type of fluid, the timing of administration and the volume
      administrated. Following much discussion and ongoing controversy on colloids versus
      crystalloids and the ideal composition of the various intravenous solutions, the main focus
      more recently has been on the volume of fluids.

      Fluid therapy strategies have been developed and implemented in clinical practice over
      several decades. The data suggest that aggressive or liberal intraoperative fluid
      resuscitation is harmful during open abdominal operation, whereas a restrictive fluid
      protocol has better outcomes, including fewer postoperative complications and a shorter
      discharge time.

      However, a restrictive fluid regimen has several limitations. Overly restricted or inadequate
      fluid administration may lead to insufficient intravascular volume, tissue hypoperfusion,
      cellular oxygenation impairment and potential organ dysfunction, prolonged recovery of bowel
      function, and impair tissue oxygenation, which might ultimately impair wound healing
      including healing of anastomosis.

      Recently, the pleth-variability index (PVI) derived from respiratory variations in peripheral
      perfusion index (PI) has been suggested to be an effective dynamic indicator of fluid
      responsiveness. Different from other invasive dynamic indices, PVI provides clinicians with a
      numerical value obtained non-invasively. PVI is calculated as [(PI max - PI min)/PI max] X
      100, where PI max and PI min represent the maximal and the minimal value, respectively, of
      the plethysmographic perfusion index (PI) over one respiratory cycle. PI is the ratio between
      pulsatile and non-pulsatile infrared light absorption from the pulse oximeter, and it is
      physiologically equivalent to the amplitude of the plethysmographic waveform. A PVI value of
      >13% before volume expansion discriminated between fluid responders and non responders with
      81% sensitivity and 100% specificity.
    

Intervention name(s): restrictive fluid strategy; conservative fluid strategy
Intervention type(s): Procedure; Procedure
Intervention description(s): restrictive lactated ringers as intraoperative fluid therapy in a dose of 6ml/kg/hour; conservative lactated ringers as intraoperative fluid therapy in a dose of 12ml/kg/hour
Other intervention name(s): fluid therapy; conservative fluid therapy
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Prevention