Comparison of Analgesic Requirements in Patients Receiving Nuss Operation Using 2 Different Anesthetic Adjuvants

Study Overview
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Brief Summary
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Nowadays, general anaesthesia is carried under balanced anesthesia technique in which many anesthetic adjuvants are used simultaneously, including opioid analgesics in order to reduce the amount of inhalation agents. The most popular adjuvants used are remifentanil, which is an opioid analgesic, and dexmedetomidine. Both of these agents are short acting, can be infused with targeted concentrations, excreted shortly from the body with stable hemodynamics. Remifentanil, when infused for more than 2 hours, causes hyperalgesia to increase the amount of pain postoperatively as well as the amount of opioid analgesics. However, dexmedetomidine does not cause hyperalgesia and is known to have an opioid -sparing effect. In our center. In this study, we aim to compare the effects of remifentanil and dexmedetomidine on postoperative pain in patients undergoing Nuss procedure, which is a very painful operation on the chest wall.

Official Title
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Comparing Analgesic Requirements in Patients Receiving Nuss Operation Using Remifentanil or Dexmedetomidine as Anesthetic Adjuvants

Conditions
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Chest Wall Disorder

Intervention / Treatment
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* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults aged >20 Patients undergoing Nuss bar operation (pectus excavatum repair surgery) American Society of Anesthesiologists classification I   III Exclusion Criteria: Drug abuse history Chronic pain in need of continuous opioid analgesics administration History of psychiatric diseases Preoperative bradycardia (heart rate < 50/min) or arrythmia Cardiac diseases other than diabetes or hypertension - coronary artery disease, ischemic heart disease Moderate liver or kidney dysfunction Pregnant or breast feeding women Hypersensitivity to the study drugs Patients who do not agree to participate

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Remifentanil group<br>In both interventional groups, Sevoflurane is used as an inhalational agent, in 0.5-1.5% age-adjusted Minimal Alveolar Concentration (MAC). As explained above, remifentanil is infused with Target Controlled Infusion pump, and concentration is adjusted so that Bispectral index (BIS) is maintained as 40-60, which means that the patients are maintained in general anesthesia. Remifentanil is usually infused with the effect site concentration of 2.0 to 6.0 ng/ml during general anesthesia. If bradycardia or hypotension develops due to remifentanil infusion, the infusion rate could be reduced, or inotropic, vasopressor, anticholinergic agents can be used (ephedrine, atropine, etc.) to correct the side effects of the drug, or the drug infusion can even be ceased. At the end of the surgery when skin closure starts, remifentanil infusion will be stopped. | Drug: Dexmedetomidine<br>* Comparing effects of remifentanil versus dexmedetomidine<br>* Other names: Remifentanil;|
| Active Comparator: Dexmedetomidine group<br>In both interventional groups, Sevoflurane is used as an inhalational agent, in 0.5-1.5% age-adjusted MAC (Minimal Alveolar Concentration). As explained above, dexmedetomidine is infused with syringe pump, and concentration is adjusted so that Bispectral index (BIS) is maintained as 40-60, which means that the patients are maintained in general anesthesia. Dexmedetomidine is loaded for 10 minutes in 1mcg/kg, and then infusion rate is set between 0.4 to 0.6mcg/kg/hour for this study. If bradycardia or hypotension develops due to remifentanil infusion, the infusion rate could be reduced, or inotropic, vasopressor, anticholinergic agents can be used (ephedrine, atropine, etc.) to correct the side effects of the drug, or the drug infusion can even be ceased. At the end of the surgery when skin closure starts, dexmedetomidine infusion will be stopped. | Drug: Dexmedetomidine<br>* Comparing effects of remifentanil versus dexmedetomidine<br>* Other names: Remifentanil;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analogue Scale | Pain scale ranges from 0 to 10. 0 means no pain at all, and 10 being the most severe pain anyone can imagine. | Between 1 6 hours postoperatively. | 
| Visual Analogue Scale | Pain scale ranges from 0 to 10. 0 means no pain at all, and 10 being the most severe pain anyone can imagine. | Between 6 12 hours postoperatively. | 
| Visual Analogue Scale | Pain scale ranges from 0 to 10. 0 means no pain at all, and 10 being the most severe pain anyone can imagine. | Between 12 24 hours postoperatively. | 
| Visual Analogue Scale | Pain scale ranges from 0 to 10. 0 means no pain at all, and 10 being the most severe pain anyone can imagine. | Between 24 48 hours postoperatively. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Amount of postoperative intravenous patient controlled analgesics (PCA) used |  | At 60 minutes after the end of surgery | 
| Amount of fentanyl used postoperatively at the recovery unit | Amount in micgrograms per wegith in kilograms (migrogram/kilogram) | At 60 minutes after the end of surgery | 
| Time needed for postoperative rescue opioid analgesics |  | At 60 minutes after the end of surgery | 
| Amount of remifentanil or dexmedetomidine used intraoperatively |  | Immediately at the end of the surgery | 
| Intraoperative hemodynamic change: Systolic blood pressure |  | 1 minute after monitoring (of blood pressure, heart rate, pulse oxymeter and electrocardiogram) starts, when the patient arrives at the operating room | 
| Intraoperative hemodynamic change: Diastolic blood pressure |  | 1 minute after monitoring (of blood pressure, heart rate, pulse oxymeter and electrocardiogram) starts, when the patient arrives at the operating room | 
| Intraoperative hemodynamic change: mean blood pressure |  | 1 minute after monitoring (of blood pressure, heart rate, pulse oxymeter and electrocardiogram) starts, when the patient arrives at the operating room | 
| Intraoperative hemodynamic change: heart rate |  | 30 minutes after the induction of anesthesia | 
| Intraoperative hemodynamic change: mean blood pressure |  | At the end of the surgery, average of 90minutes after the induction of anesthesia | 
| Intraoperative hemodynamic change: heart rate |  | At the end of the surgery, average of 90minutes after the induction of anesthesia | 
| Intraoperative hemodynamic change: Systolic blood pressure |  | At the end of the surgery, average of 90minutes after the induction of anesthesia | 
| Intraoperative hemodynamic change: Diastolic blood pressure |  | At the end of the surgery, average of 90minutes after the induction of anesthesia | 
| Rescue drugs (inotropics or vasopressors) used in order to correct hypotension or bradycardia |  | Intraoperatively | 
| Postoperative complications | Number of events that happened to the patient: e.g. Yes or No, and how many times. Nausea/vomiting, hypotension, respiratory depression, urinary retension, dizziness, transient cease in use of intravenous patient controlled analgesics (PCA) | Between 1 6 hours postoperatively | 
| Postoperative complications | Number of events that happened to the patient: e.g. Yes or No, and how many times. Nausea/vomiting, hypotension, respiratory depression, urinary retension, dizziness, transient cease in use of intravenous patient controlled analgesics (PCA) | Between 12 24 hours postoperatively | 
| Postoperative complications | Number of events that happened to the patient: e.g. Yes or No, and how many times. Nausea/vomiting, hypotension, respiratory depression, urinary retension, dizziness, transient cease in use of intravenous patient controlled analgesics (PCA) | Between 24 48 hours postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pectus Excavatum