Different Doses of Sevoflurane During Induction of Anesthesia on Emergence Delirium in Children

Study Overview
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Brief Summary
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The investigators aim to reduce the incidence of emergence delirium in children aged 2-7 years old by using two different doses of sevoflurane during inhalatory induction of anesthesia.

Detailed Description
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Sevoflurane is an inhalational agent widely used in general anesthesia, both for induction and maintenance of anesthesia. It is not irritative on the airways and has a pleasant smell. Within their properties are: low partition coefficient blood / gas (rapid induction and awakening), low heart, liver and kidney toxicity. Inhalational induction in pediatric anesthesia with this agent is frequent to avoid vein puncture in awake patients and is generally done with maximum doses available to obtain a fast loss of consciousness. Emergence delirium (ED) is frequent in children. It is defined as a mental disorder during recovery from general anesthesia that may include hallucinations, delusions and confusion expressed by crying, restlessness and involuntary physical activity. It usually lasts for 30 minutes and is not necessarily related to pain. During this episodes, children can hurt themselves or others, lose vascular catheters or other invasive devices. ED can generate anxiety and stress in caretakers, delay transfer from Post-Anesthesia Care Units (PACU), increase costs of medical attention and increase use of opioids or other sedatives. Many interventions have been used to decrease the appearance of ED such as dexmedetomidine, clonidine, benzodiazepines, propofol among others but with no consistent results. The use of sevoflurane has been linked with ED in children and it can induce seizures in high doses (over 2 MAC). The aim of this study is to test whether using a lower dose of sevoflurane (5%) during induction of anesthesia in children results in less ED than using higher doses (8%).

Official Title
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Emergence Delirium in Children: a Randomized Clinical Trial of Different Doses of Sevoflurane During Induction of Anesthesia

Conditions
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Delirium

Intervention / Treatment
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* Other: Sevoflurane 8%
* Other: Sevoflurane 5%


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Surgery with caudal block: circumcision (phimosis), hernioplasty (inguinal hernia) American Society of Anesthesiologists (ASA) classification of I or II Exclusion Criteria: Use of Total Intravenous Anesthesia (TIVA) Familiar or personal history of Malignant Hyperthermia Contraindication to caudal block Parents or legal guardians do not sign informed consent

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 7 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: High dose sevoflurane<br>Inhaled sevoflurane 8% during induction of general anesthesia (from the start of gas administration to the insertion of a laryngeal mask). After laryngeal mask insertion, sevoflurane will be reduced to 4%. Caudal block with L-bupivacaine 0.25% will be performed in all children. After caudal block, sevoflurane will be reduced to 0.75 MAC according to age of the child and maintained until the end of surgery After surgery, PAED and pain scales will be administered every 15 minutes up to 2 hours after surgery. | Other: Sevoflurane 8%<br>* Sevoflurane 8% (high dose) during anesthesia induction<br>* Other names: Sevorane;|
| Other: Low dose sevoflurane<br>Inhaled sevoflurane 5% during induction of general anesthesia (from the start of gas administration to the insertion of a laryngeal mask). After laryngeal mask insertion, sevoflurane will be reduced to 4%. Caudal block with L-bupivacaine 0.25% will be performed in all children. After caudal block, sevoflurane will be reduced to 0.75 MAC according to age of the child and maintained until the end of surgery After surgery, PAED and pain scales will be administered every 15 minutes up to 2 hours after surgery. | Other: Sevoflurane 5%<br>* Sevoflurane 5% (low dose) during anesthesia induction<br>* Other names: Sevorane;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Emergence delirium | Emergence delirium will be evaluated with the Pediatric Anesthesia Emergence Delirium scale every 15 minutes | From end of gas administration up to 2 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain | Pain will be evaluated according to age of children: CHIPPS scale for under 3 years, faces for children between 4 and 6 years old, Visual Analogue Scale (VAS) with older children. | From end of gas administration up to 2 hours after surgery | 
| Bispectral Index | Bispectral Index (BIS) monitoring will be used during surgery and recorded at following times: after insertion of IV access, after insertion of laryngeal mask, after caudal block, after lowering dose of sevoflurane to 0.75 MAC, after skin incision, at the end of surgery | From start of induction until end of surgery | 
| Heart rate | Measured with pulse oximetry, recorded at following times: after insertion of IV access, after insertion of laryngeal mask, after caudal block, after lowering dose of sevoflurane to 0.75 MAC, after skin incision, at the end of surgery | From start of induction until end of surgery | 
| Blood pressure | Measured with non-invasive blood pressure cuff, recorded at following times: after insertion of IV access, after insertion of laryngeal mask, after caudal block, after lowering dose of sevoflurane to 0.75 MAC, after skin incision, at the end of surgery | From start of induction until end of surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Emergence delirium, Sevoflurane, Pediatric anesthesia