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 utility of Pupillary Dilatation Reflex (PRD) for monitoring pain perception intraoperatively and its influence on intraoperative blood loss, quality of surgical field using Boezaart Bleeding Scale (BBS) in patients undergoing functional sinus surgery (FESS) under total intravenous anaesthesia using propofol or volatile anaesthesia using sevoflurane or desflurane

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, Pupillary Dilatation Reflex (PRD) was 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 it constitutes the indication for administration of rescue analgesia intraoperatively. This study aims at evaluating utility of PRD-directed analgesia using remifentanil on the intraoperative blood loss, haemodynamic stability and time duration of surgery in patients undergoing functional sinus surgery (FESS) under total intravenous anaesthesia using propofol or volatile anaesthesia using sevoflurane or desflurane 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 current literature provides conflicting findings in this area if the sort of anaesthetic used influences quality of the surgical field.

Official Title
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Comparative Study of Influence of Total Intravenous Anaesthesia (TIVA) and Volatile Anaesthesia Using Sevoflurane or Desflurane on the Intraoperative Blood Loss During Functional Endoscopic Sinus Surgery

Conditions
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Endoscopic Sinus Surgery

Intervention / Treatment
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* Drug: Remifentanil
* Device: pupillary dilatation reflex


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 general 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SEVOFLURANE INHALATIONAL ANAESTHESIA<br>concentration of sevoflurane in the exhalation gas will be maintained to ensure target SE between 40, remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute, intraoperatively PRD measurement every 15 minutes; when PRD>5% infusion speed of remifentanyl will be increased by 50% every 5 minutes until PRD decreases below 5% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes until PRD decreases below 5%<br>* Other names: Remifentanil infusion;Device: pupillary dilatation reflex<br>* PRD value will me measured before the start of FESS after 5 minutes of remifentanyl infusion, when PRD sensitivity > 5% , infusion of remifentanyl will be increased by 50% until PRD sensitivity <5% and FESS will be started ; intraoperatively infusion of remifentanyl will be increased by 50% until PRD sensitivity <5%<br>|
| Experimental: DESFLURANE INHALATIONAL ANAESTHESIA<br>concentration of desflurane in the exhalation gas will be maintained to ensure target SE 40, remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute, intraoperatively PRD measurement every 15 minutes; when PRD>5% infusion speed of remifentanyl will be increased by 50% every 5 minutes until PRD decreases below 5% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes until PRD decreases below 5%<br>* Other names: Remifentanil infusion;Device: pupillary dilatation reflex<br>* PRD value will me measured before the start of FESS after 5 minutes of remifentanyl infusion, when PRD sensitivity > 5% , infusion of remifentanyl will be increased by 50% until PRD sensitivity <5% and FESS will be started ; intraoperatively infusion of remifentanyl will be increased by 50% until PRD sensitivity <5%<br>|
| Experimental: TIVA USING PROPOROL<br>Infusion of propofol will be adjusted at target of SE 40,remifentanyl solution will be administered intravenously at a rate 0,25 mcg/kg of body weight/minute, intraoperatively PRD measurement every 15 minutes; when PRD>5% infusion speed of remifentanyl will be increased by 50% every 5 minutes until PRD decreases below 5% | Drug: Remifentanil<br>* a rate of infusion will be increased by 50% every 5 minutes until PRD decreases below 5%<br>* Other names: Remifentanil infusion;Device: pupillary dilatation reflex<br>* PRD value will me measured before the start of FESS after 5 minutes of remifentanyl infusion, when PRD sensitivity > 5% , infusion of remifentanyl will be increased by 50% until PRD sensitivity <5% and FESS will be started ; intraoperatively infusion of remifentanyl will be increased by 50% until PRD sensitivity <5%<br>|

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 | 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 | 
| condition of surgical field | the surgeon will assess the quality of surgical field using BBS when the operation of FESS | 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 | 
| concentration of desflurane in end-expiratory gas | The investigators will measure theconcentration of desflurane in end-expiratory gas intraoperatively | intraoperative assessment | 
| concentration of sevoflurane in end-expiratory gas | The investigators will measure the concentration of sevoflurane in end-expiratory gas intraoperatively | intraoperative assessment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pupillary Dilatation Reflex (PRD), Intraoperative Blood Loss (IBL), Boezaart Bleeding Scale (BBS), Spectral Entropy (SE), Adequacy of Anaesthesia (AoA), Total Intravenous Anaesthesia (TIVA), Sevoflurane, Desflurane