SPI-guided vs PRD-guided Analgesia During FESS for Intraoperative Blood Loss

Study Overview
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Brief Summary
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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
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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.

Official Title
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Comparative Study of Influence of Different Techniques of Remifentanil Titration During Functional Endoscopic Sinus Surgery Under Total Intravenous Anaesthesia (TIVA)

Conditions
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Endoscopic Sinus Surgery

Intervention / Treatment
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* Drug: Remifentanil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: written consent to participate in the study written consent to undergo functional endoscopic sinus surgery under total intravenous anaesthesia ASA (American Society of Anesthesiologists) I-III Exclusion Criteria: age under 18 years old allergy to propofol pregnancy any anatomical malformation making PRD or SE measurement impossible

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SPI-guided remifentanyl<br>remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute, SPI will be monitored on-line; when delta SPI>15, infusion speed of remifentanyl will be increased by 50% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes<br>* Other names: Remifentanil infusion;|
| Experimental: PRD-guided remifentanyl<br>solution remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute, PRD measurement every 15 minutes; when PRD>5% infusion speed of remifentanyl will be increased by 50% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes<br>* Other names: Remifentanil infusion;|
| Experimental: BBS-guided remifentanyl<br>BBS assessment every 5 minutes, solution remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute; when BBS>2, infusion speed of remifentanyl will be increased by 50% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes<br>* Other names: Remifentanil infusion;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood loss postoperatively | the investigators will measure the amount of blood loss in the suction bag in millilitres (ml) using a syringe after operation of FESS is completed | end of operation,' assessment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| heart rate stability intraoperatively | the investigators will measure heart rate during TIVAevery 5 minutes up to the end of the operation | end of operation,' assessment | 
| hemodynamic stability intraoperatively | the investigators will measure blood pressure every 5 minutes during TIVA, every 5 minutes up to the end of the operation | intraoperative assessment | 
| PRD-guided pain perception intraoperatively | The investigators will measure PRD value and adjust infusion speed of remifentanyl, in the case of PRD value >5% the speed of remifentanyl infusion will accelerate by 50%, intraoperatively, every 15 minutes or at any change of BBS, up to the end of the operation | intraoperative assessment | 
| SPI-guided pain perception intraoperatively | The investigators will measure SPI values and adjust infusion speed of remifentanyl, in the case of delta SPI>15 the speed of remifentanyl infusion will accelerate by 50%, intraoperatively, every 1 minute, up to the end of the operation | intraoperative assessment | 
| condition of surgical field | the surgeon will assess the quality of surgical field using BBS when the operation of FESS is performed, every 5 minutes or at any change of BBS form the beginning till the end of surgery, up to the end of the operation | intraoperative assessment | 
| total consumption of propofol | The investigators will measure the consumption of propofol intraoperatively | end of operation assessment | 
| total consumption of remifentanil | The investigators will measure the consumption of remifentanyl intraoperatively | end of operation assessment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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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)