Comparison of Remifentanil and Dexmedetomidine for Monitored Anaesthesia Care During Vertebroplasty and Kyphoplasty

Study Overview
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Brief Summary
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This randomised, double-blind study compared remifentanil and dexmedetomidine for monitored anaesthesia care (MAC) during minimally invasive corrections of vertebral compression fracture (vertebroplasty (VP) and kyphoplasty (KP)). In total, 80 ASA physical status I-III patients scheduled for VP and KP randomly received remifentanil or dexmedetomidine to maintain OAA/S scale ≤ 4 during the procedures. Multiple hemodynamic variables of patients were recorded and the frequency of oxygen desaturation, respiratory depression, intraoperative need for other opioids, recovery time, operator satisfaction score, and patients' overall pain experiences were also compared. The investigators are expecting that both remifentanil and dexmedetomidine appear to be quite safe for MAC during VP and KP. Thus, dexmedetomidine may be an alternative for MAC during VP and KP in elderly patients.

Detailed Description
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All patients fasted for 8 h before the procedure and were premedicated with midazolam 0.02 mg/kg. In the prone position, patients were monitored by ECG, non-invasive blood pressure, and pulse oximetry, and received supplemental oxygen (3 L/min) via a nasal cannula during the procedure. Study drugs were prepared in 20 mL and 50 mL syringes to maintain a double-blind design. One anaesthesiologist administered normal saline or dexmedetomidine contained in the 20-mL syringe during the initial 10 min for loading dose of dexmedetomidine. Then, another investigator who did not know which syringes contained remifentanil or dexmedetomidine adjusted the infusion rate with a 50-mL syringe according to patients' response. After all patients in both groups received a bolus dose of propofol 0.3 mg/kg, patients given remifentanil received continuous infusion of the drug at 1-5 µg/kg/h, and patients receiving dexmedetomidine were given that drug at 0.3-0.4 µg/kg over 10 min, followed by continuous infusion of dexmedetomidine 0.2-1 µg/kg/h throughout the procedure. Levels of patient sedation were checked during the procedure and infusion rates of the study drugs were adjusted to maintain alertness/sedation below 4 on the OAA/S scale. Mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2), respiratory rate (RR), and adverse effects of the study drugs were recorded during the procedure. Ephedrine 5 mg was injected when systolic blood pressure decreased below 90 mmHg. Duration of PACU stay was also recorded. Operator satisfaction score and patient's overall pain experience were also recorded.

Official Title
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Comparison of Remifentanil and Dexmedetomidine for Monitored Anaesthesia Care

Conditions
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Fractures, Compression

Intervention / Treatment
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* Drug: Remifentanil
* Drug: Dexmedetomidine
* Drug: midazolam
* Drug: propofol
* Drug: ephedrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients who are scheduled for vertebroplasty or kyphoplasty under monitored anesthesia care ASA status I-III aged more than 65 years old. Exclusion Criteria: obesity (BMI > 30 kg/m2) hypotension (systolic blood pressure < 100 mmHg) bradycardia (heart rate < 60 bpm) heart block baseline oxygen desaturation (SpO2 < 90%) sleep apnea asthma, or chronic obstructive pulmonary disease those who refused to give informed consent

Ages Eligible for Study
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Minimum Age: 65 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 |
| --- | --- |
| Experimental: Remifentanil<br>Remifentanil is commonly used in monitored anesthesia care because of its rapid onset and short duration of action. | Drug: Remifentanil<br>* Patients given remifentanil received continuous infusion of the drug at 1-5 µg/kg/h<br>* Other names: Ultiva;|
| Experimental: Dexmedetomidine<br>Dexmedetomidine is a highly selective α 2 adrenergic agonist and has both sedative and analgesic properties, and rarely causes respiratory depression. | Drug: Dexmedetomidine<br>* Patients receiving dexmedetomidine were given that drug at 0.3-0.4 µg/kg over 10 min, followed by continuous infusion of 0.2 1 µg/kg/h<br>* Other names: Precedex;|
| Other: midazolam<br>Midazolam is commonly used before induction for its anxiolytic effect. | Drug: Remifentanil<br>* Patients given remifentanil received continuous infusion of the drug at 1-5 µg/kg/h<br>* Other names: Ultiva;Drug: Dexmedetomidine<br>* Patients receiving dexmedetomidine were given that drug at 0.3-0.4 µg/kg over 10 min, followed by continuous infusion of 0.2 1 µg/kg/h<br>* Other names: Precedex;Drug: midazolam<br>* All patients were premedicated with midazolam 0.02 mg/kg before induction.<br>|
| Other: propofol<br>Propofol is the most commonly used in sedative analgesia for its rapid onset and recovery time. | Drug: Remifentanil<br>* Patients given remifentanil received continuous infusion of the drug at 1-5 µg/kg/h<br>* Other names: Ultiva;Drug: Dexmedetomidine<br>* Patients receiving dexmedetomidine were given that drug at 0.3-0.4 µg/kg over 10 min, followed by continuous infusion of 0.2 1 µg/kg/h<br>* Other names: Precedex;Drug: propofol<br>* All patients in both groups received a bolus dose of propofol 0.3 mg/kg for sedative effect.<br>* Other names: Pofol;|
| Other: ephedrine<br>Adrenergic agonist to treat hypotension | Drug: Remifentanil<br>* Patients given remifentanil received continuous infusion of the drug at 1-5 µg/kg/h<br>* Other names: Ultiva;Drug: Dexmedetomidine<br>* Patients receiving dexmedetomidine were given that drug at 0.3-0.4 µg/kg over 10 min, followed by continuous infusion of 0.2 1 µg/kg/h<br>* Other names: Precedex;Drug: ephedrine<br>* Ephedrine 5 mg was injected when systolic blood pressure decreased below 90 mmHg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The frequencies of oxygen desaturation during procedures |  | About 1 hour through the procedures |