Comparative Study on the Effects of Epidural Dexmedetomidine on Heart Rate Variability During General Anesthesia in Patients Undergoing Gastrectomy

Study Overview
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Brief Summary
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The use of epidural dexmedetomidine decreases the anaesthetic requirements and improved postoperative pain. Dexmedetomidine is a potent and highly selective a2-adrenoceptor agonist and has sympatholytic effect. Power spectral analysis of heart rate variability(HRV) is a useful tool to assess cardiac autonomic activity. We investigated whether preemptive epidural dexmedetomidine can develop hemodynamic change and it could be identify patients by HRV.

Conditions
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Gastric Cancer

Intervention / Treatment
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* Drug: preemptive dexmedetomidine epidural bolus injection(1.5 mcg/kg)
* Drug: normal saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients consented to spinal anesthesia were enrolled Patients aged 40 70 years olds undergoing gastrectomy No contraindication of epidural analgesia ASA class I and II Patients consented to epidural anesthesia were enrolled Exclusion Criteria: Patients with hypovolemia, coagulation disorders, local infection at the site of operation, history of headache, heart diseases, and history of allergy, chronic alcohol use or abuse, anemia, congenital heart diseases, bundle block, congestive heart failure or arrythmias patients who had recently received sedative drugs or were under antidepressant treatment were not included in the study

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dexmedetomidine<br> | Drug: preemptive dexmedetomidine epidural bolus injection(1.5 mcg/kg)<br>* Patients in the pre-emptive groups recived a dose of 1.5㎍/kg dexmedetomidine dissolved into normal saline 10cc before the induction of<br>|
| Placebo Comparator: normal saline<br> | Drug: normal saline<br>* patients in the control groups received the equivalent volume of normal saline.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate variability analysis | Heart rate variability analysis was performed according to the Task Force recommendations. Frequency domain analysis was based on fast Fourier transformation. Power spectrum densities were calculated for low frequencies (LF: 0.04-0.15 Hz) and high frequencies (HF: 0.15-0.4 Hz) informalized units, defined as the LF or HF proportional part of the total power. Baseline and 30min after the injection of the study drug. | 5min perioids after fluid resuscitation. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Epidural injection | And secondary data collection was done at 30 min after the epidural injection of the study drug. All of the HRV analysis was done before anaesthesia induction. | at 30 min after the epidural injection of the study drug | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine, heart rate variability, preemptive epidural, gastrectomy