Atropine-effect During Propofol/Remifentanil Induction

Study Overview
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Brief Summary
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Remifentanil is a widely used potent intravenous opioid with the advantage of having a short time of action. Compared to other opiates however remifentanil generates more intense hemodynamic side-effects. In ophthalmic surgery the specific anesthesiological challenges necessitate the administration of a combination of relatively high doses of analgesics on the one hand and a short time for postoperative recovery from anesthesia on the other. For these reasons, anesthetic management often consists of a combination of relatively high doses of propofol and remifentanil. A primary concern during this deep propofol/remifentanil anesthesia is preserving hemodynamic stability and adequate tissue oxygenation. Previous research of the investigators group has revealed that atropine has an exceptionally beneficial effect on hemodynamics as well as on tissue oxygenation. Therefore, the investigators hypothesize that administration of intravenous atropine during induction of propofol/remifentanil may have a positive effect on the hemodynamic profile and peripheral and cerebral tissue oxygenation during and after induction of anesthesia.

Official Title
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Evaluation of the Effects of the Addition of Atropine During Propofol/Remifentanil Induction of Anesthesia on Hemodynamics, Microvascular Blood Flow and Tissue Oxygenenation in Patients Undergoing Ophthalmic Surgery

Conditions
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Anesthesia-induced Negative Hemodynamic Effects

Intervention / Treatment
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* Drug: Placebo
* Drug: Atropine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients requiring general anaesthesia; Patient's age ≥ 18 years and older; Patient and surgical procedure appropriate for treatment with either sufentanil or remifentanil. Exclusion Criteria: Patient's refusal; Pregnancy; Patient's age < 18 years; Patients in which atropine is contra-indicated, such as severe aortic valve stenosis, hypertrophic cardiomyopathy or coronary artery disease.

Ages Eligible for Study
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Minimum Age: 18 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: Single Group Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: General anesthesia + placebo<br>Propofol/remifentanil anesthesia + saline | Drug: Placebo<br>* Saline<br>* Other names: Saline;|
| Active Comparator: General anesthesia + atropine<br>Propofol/remifentanil anesthesia + atropine | Drug: Atropine<br>* Atropine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac output |  | During anesthesia | 
| Peripheral tissue oxygen saturation |  | During anesthesia | 
| Cerebral tissue oxygen saturation |  | During anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate |  | During anesthesia | 
| Mean arterial blood pressure |  | During anesthesia | 
| Systemic vascular resistance |  | During anesthesia |