SPI-guided vs PRD-guided Analgesia During FESS for Intraoperative Blood Loss
Condition: Endoscopic Sinus Surgery
Study type: Interventional

Summary: 
      The aim of this randomized trial is to assess the efficacy of analgesia , compare the utility
      of Pupillary Dilatation Reflex (PRD), Surgical Pleth Index (SPI) for monitoring pain
      perception intraoperatively and their influence on intraoperative blood loss, quality of
      surgical field using Boezaart Bleeding Scale (BBS) in patients undergoing functional sinus
      surgery (FESS)
    

Detailed description: 
      Intraoperative blood loss during FESS constitutes a major problem for a surgeon because it
      influences quality of surgical field. Each incident of haemorrhage makes the operator stop
      the procedure in order to bring back the optimal visualization of the intranasal anatomy. In
      the end it prolongs the time of procedure.

      Currently, intraoperative blood loss is estimated based on Boezaart Bleeding Scale (BBS) (0 -
      no bleeding (cadaveric conditions), 1 - Slight bleeding, no suctioning required, 2 - Slight
      bleeding, occasional suctioning required, 3 - Slight bleeding, frequent suctioning required;
      bleeding threatens surgical field a few seconds after suction is removed, 4 - Moderate
      bleeding, frequent suctioning required, and bleeding threatens surgical field directly after
      suction is removed, 5 - Severe bleeding, constant suctioning required; bleeding appears
      faster than can be removed by suction; surgical field severely threatened and surgery usually
      not possible).

      Recently, the Surgical Pleth Index (SPI) and Pupillary Dilatation Reflex (PRD) were added as
      a surrogate variable showing the nociception-antinociception balance into above mentioned
      parameters constituting a novel approach in monitoring patients intraoperatively, known as
      adequacy of anaesthesia (AoA) or tailor-made anaesthesia. PRD value >5% reflects increased
      sensitivity to painful stimulus as well as delta SPI>10 or any SPI>50, and they constitute
      the indication for administration of rescue analgesia intraoperatively.

      This study aims at evaluating utility of SPI-directed analgesia or PRD-directed analgesia or
      Boezaart scale-directed analgesia using remifentanil on the intraoperative blood loss,
      haemodynamic stability and time duration of surgery.

      Currently, FESS is most often performed using total intravenous anaesthesia (TIVA) which is
      by majority of anaesthesiologists believed to reduce the intraoperative blood loss compared
      to general anaesthesia using volatile anaesthetics, but literature provides conflicting
      findings in this area.
    

Intervention name(s): Remifentanil
Intervention type(s): Drug
Intervention description(s): a rate of infusion will be increased by 50% every 5 minutes
Other intervention name(s): Remifentanil infusion
Intervention MeSH terms: Remifentanil
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Diagnostic
Keywords: Surgical Pleth Index (SPI); Pupillary Dilatation Reflex (PRD); Intraoperative Blood Loss (IBL); Boezaart Bleeding Scale (BBS); Spectral Entropy (SE); Adequacy of Anaesthesia (AoA); Total Intravenous Anaesthesia (TIVA)