Influence of Monitoring the Depth of General Anesthesia Upon the Incidence of PONV and Emergence Delirium in Children Undergoing Endoscopic Adenoidectomy in General Anesthesia

Study Overview
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Brief Summary
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The study has been designed as a prospective randomized clinical trial. Due to the use of a bispectral (BIS) monitor in the interventional arm, the study will not be blinded for the anesthetist. The total planned number of study subjects is 100. Patients will be randomly randomized upon arrival to the operating theatre (using the envelope method) into the interventional arm (BIS monitoring of the depth of general anesthesia), and into the control group (standard management of general anesthesia to minimum alveolar concentration (MAC) 1,0). The target values of the depth of general anesthesia according to BIS are between 40 and 60.

Detailed Description
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The condition of postoperative nausea and vomiting (PONV) is defined as nausea and vomiting, which appears within 24 hours after the performance of a surgical/diagnostic procedure in general anesthesia. PONV is perceived as a complication of minor importance in perioperative medicine, nevertheless, it is one of the most frequent causes of morbidity in pediatric patients in the early postoperative period, associated with a number of adverse effects. The incidence of PONV in pediatric age is reported in scientific literature to be between 8.9 and 42 percent. The pathogenesis of PONV is complex and has not been fully clarified yet. The development of PONV depends on individual and anaesthesiology risk factors, and the type of surgical procedure. The use of inhalation anesthetics demonstrably increases the incidence of PONV, especially in the course of the first two hours after the procedure. The need for inhalation anesthetic is individually variable, and it is not possible to empirically define, which dose will lead to an adequate depth of anesthesia. Excessively deep, as well as too shallow anesthesia may result in increasing the incidence of postoperative complications, including PONV. The depth of anesthesia and unconsciousness may be monitored with BIS (bispectral index). The investigators presume that optimization of the supply of inhalation anesthetic according to BIS, so-called BIGA (Bispectral index guided anesthesia) will lead to decreasing the incidence of PONV. Several clinical studies performed on the adult population have demonstrated that using BIGA leads to a decreased incidence of PONV in adult patients undergoing gynecological procedures. As far as pediatric anesthesiology is concerned, similar studies are still lacking. Inhalation anesthesia is also associated with another complication in the early postoperative period - so-called emergence delirium (ED). It is a condition of psychomotor restlessness, perception disorders, and excitation of the child observed after completion of anesthesia. The incidence of ED in the pediatric population anesthesia is between 10 and 80 percent, most frequently within the first 10-30 minutes after discontinuation of the administration of anesthetics. The condition is characterized by confusion, loss of orientation, crying, restlessness, and non-cooperation of the child. The causes of ED have not been fully clarified. One of the possible causes may be the rapid emergence of the child from anesthesia after discontinuation of the inhalation anesthetic. The incidence of ED is highest with Sevoflurane, which is the most frequently used inhalation anesthetic in pediatric anesthesia. Optimization of the depth of general anesthesia and decreasing the consumption of inhalation anesthetic may lead to decreasing the incidence of emergence delirium objectified according to the Paediatric Anaesthesia Emergence Delirium (PAED) score. The study has been designed as a prospective randomized clinical trial. Due to the use of the BIS monitor in the interventional arm, the study will not be blinded for the anesthetist. The total planned number of study subjects is 100. Patients will be randomly randomized upon arrival to the operating theatre (using the envelope method) into the interventional arm (BIS monitoring of the depth of general anesthesia), and into the control group (standard management of general anesthesia to minimum alveolar concentration (MAC) of 1.0). The target values of the depth of general anesthesia according to BIS are between 40 and 60. General anesthesia will be administered according to the following uniform anaesthesiology protocol: Inhalation introduction with Sevoflurane (8% on the vaporizer), in a carrier mixture of gases oxygen : air, with the flow of 41/min and oxygen concentration of 50%. In the intervention group, BIS will be introduced as soon as possible. After achieving a sufficient depth of anesthesia, a peripheral venous catheter will be introduced, followed with intravenous administration of opioid - Sufentanil in the dose of 0.2ucg/kg, and intravenous administration of Paracetamol in the dose of 15mg/kg. The infusion will be administered in the course of the surgical procedure - isotonic crystalloid solution Benelyte in the dose of 10ml/kg/hour. Breathing passageways will be secured with an armed laryngeal mask, according to the standard procedure applied at the author's center. Considering the character of the study, no antiemetic prophylaxis will be administered. After completion of the surgical procedure and emergence from general anesthesia, the child will be transferred to post-anesthesia care unit (PACU), where, apart from the monitoring of vital functions, also the incidence of PONV and the PAED score (in the 10th minute, 30th minute, and 60th minute) will be observed. At the Ear-Nose-Throat (ENT) department, the authors will record the Baxter Retching Faces (BARF) scale in pre-determined time intervals, and the incidence of PONV in the course of the whole hospitalization.

Official Title
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Influence of Monitoring the Depth of General Anesthesia Upon the Incidence of PONV and Emergence Delirium in Children Undergoing Endoscopic Adenoidectomy in General Anesthesia

Conditions
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Postoperative Nausea, Postoperative Vomiting, Emergence Delirium

Intervention / Treatment
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* Other: BIS monitor
* Other: Standard care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 3-8 years of age Indication for the performance of endoscopic adenoidectomy in general anesthesia ASA I a II Consent of a parent/a guardian Exclusion Criteria: ASA III and more Disapproval of a parent/a guardian Disapproval of the patient Allergies to medication used in the course of the study Contraindication of inhalation introduction to anesthesia and the way of securing breathing passageways in the study, according to the attending anesthetist

Ages Eligible for Study
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Minimum Age: 3 Years
Maximum Age: 8 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
Interventional Model Description: The study subjects will be randomized into two study arms.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: BIS monitoring<br>Study subjects randomized in this study arm will have the depth of anesthesia controlled with the BIS monitor. | Other: BIS monitor<br>* BIS monitor is used to control and monitor the depth of general anesthesia.<br>|
| Active Comparator: Standard care<br>Study subjects randomized in this study arm will receive standard anesthesiology care according to the usual procedures used at the study centre. | Other: Standard care<br>* Standard anesthesiology care according to the protocol of the study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of PONV | The incidence of PONV will be observed and recorded using the Baxter Reetching Faces (BARF) scale and recording the number of PONV episodes. | During the hospitalisation of the patient, i.e. up to 5 days | 
| Incidence of ED | The incidence of ED will be observed and recorded using the PAED score. | During the hospitalisation of the patient, i.e. up to 5 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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postoperative nausea, postoperative vomiting, emergence delirium, bispectral monitor, pediatric anesthesia, adenoidectomy, general anesthesia