Assessment of the Nociception During Lumbar Surgery

Study Overview
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Brief Summary
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The aim of the study is to assess the accuracy of a new paradigm in measuring the level of nociception during lumbar surgery. The paradigm is based the measurement of the baroreflex in response to noxious stimuli in anesthetized patients.

Detailed Description
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The study aims at exploring the changes in the baroreflex induced by 3 noxious stimulation in anesthetized patients: tracheal intubation, tetanic stimulus, and surgical incision. Patients are randomly assigned to one of 2 groups: remifentanil-2 or remifentanil-4, corresponding to the target effect site concentration of this drug delivered through a TCI system. Other drugs included propofol and cisatracurium. The paradigm exploring the baroreflex collects information continuously recorded of the RR intervals and the changes in systolic arterial pressure, before and during noxious stimuli. The hypothesis is that this paradigm explores nociception as the group with smaller doses in remifentanil will have more cardiovascular reactions in response to noxious stimuli.

Official Title
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Assessment of the Nociception During Lumbar Surgery

Conditions
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Lumbar Surgery

Intervention / Treatment
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* Drug: remifentanil
* Drug: remifentanil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA classification I-II undergoing lumbar surgery for discal hernia body mass index <30 kg/m2 Exclusion Criteria: ASA classification III-IV cardiac history that precludes RR recording : atrial fibrillation, arterial hypertension, active cardiac pacing, chronic treatment with beta-blockers, alpha-blockers, calcium-blockers and angiotensin receptors inhibitors diabetes regular intake of cocaine, alcohol pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: remifentanil-2<br>In this group, patients are receiving a continuous i.v. infusion of remifentanil according to a target effect site concentration of 2 ng/ml. | Drug: remifentanil<br>* anesthesia is induced and maintained with a target-controlled infusion of remifentanil at 2 ng/ml.<br>|
| Active Comparator: remifentanil-4<br>In this group, patients are receiving a continuous i.v. infusion of remifentanil according to a target effect site concentration of 4 ng/ml. | Drug: remifentanil<br>* anesthesia is induced and maintained with a target-controlled infusion of remifentanil at 4 ng/ml.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in the baroreflex in response to noxious stimuli |  | intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| perioperative requirements in anesthetic agents. |  | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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nociception, intraoperative, baroreflex