Dexmedetomidine Versus Propofol in Vitreoretinal Surgery

Rutgers The State University of New Jersey

Status and phase: Completed; Phase 4

Conditions: Retinal Detachment

Treatments: Drug: Dexmedetomidine infusion; Drug: propofol

Study type: Interventional

Funder types: Other

Identifiers

NCT01001429

0120090202

Details and patient eligibility

About

The investigators would like to determine if using Dexmedetomidine alone or in a reduced dose can prevent or reduce the incidence of adverse effects, while providing adequate sedation, and respiratory stability as compared to propofol.

Full description

Alpha2 adrenergic receptor agonist have been used increasingly as a new armamentarium to provide sedative/hypnotic, analgesic, anxiolytic and sympatholytic effects in the perioperative settings. Dexmedetomidine, a selective and specific alpha2- adrenoceptor agonist has unique properties that makes it an almost ideal sedative drug for monitored anesthesia care in procedures under local or regional block. Unlike other drugs use for sedation, dexmedetomidine induces sedation that is similar to natural sleep (readily arousable) without causing respiratory depression. It attenuates the stress-induced sympathoadrenal response seen with laryngoscopy and intubation. It has anesthetic and opioid sparing effects, hence it may be a useful adjunct to general anesthesia and monitored anesthesia care in patients susceptible to narcotic induced respiratory depression. Another unique property of dexmedetomidine is that its sedative effect is reversible with Atipamezole. A previous study wherein dexmedetomidine has been used in procedures under local and regional block had shown that it provides effective sedation and better operating condition without significant respiratory depression. As a supplement to general anesthesia, it has been shown to provide stable hemodynamics. However, it is associated with some adverse events such as hypertension, hypotension and bradycardia, these commonly occur during bolus administration of the recommended dose of 1ug/kg. Post-operatively it can cause nausea and vomiting. Vitreoretinal surgery requires either an injection of local anesthetic within the muscle cone (retrobulbar block),or into the periorbital space (peribulbar block). This can be done individually or in combination. This surgery can also be done under a safer technique of retrobulbar block that is given using a sub-tenon's approach through a snip peritomy; a blunt cannula can be used with this technique mitigating the complications of retrobulbar hemorrhage or inadvertent injection into the optic nerve sheath or perforation of the globe using a sharp needle. The anesthetic goal is to provide an immobile and uncongested operative field. Hemodynamic stability of the patient is also important since some patients that require this procedure are elderly with co-morbid conditions such as hypertension, diabetes mellitus and Coronary Artery Disease (CAD). In our study we would like to investigate if Dexmedetomidine alone and in a reduced dose can prevent or reduce the incidence of adverse effects, provide hemodynamic and respiratory stability, provide adequate sedation with patient and surgeon satisfaction and compare it with Propofol.

Objectives:

Primary:

1. Adequate sedation
2. Hemodynamic and respiratory stability intraoperatively

Secondary:

1. surgeon satisfaction
2. Time to achieved " street fitness " status
3. subject satisfaction
4. Hemodynamic stability in PACU

Enrollment: 78 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• American Society of Anesthesiologists rating of I-III
• good renal and liver function

Exclusion criteria

• renal and hepatic insufficiency
• uncontrolled diabetes
• uncontrolled hypertension
• severe cardiac disease Class III or IV
• heart blocks
• chronic use of sedatives, narcotics, alcohol or illicit drugs
• allergy to either propofol or dexmedetomidine
• pregnancy or inability to tolerate technique of the study drugs

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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78 participants in 2 patient groups

Propofol

Active Comparator group

Description:

propofol 1mg/kg as a bolus intravenously followed by an infusion of 25-100 ug/kg/min

Treatment:

Drug: propofol

dexmedetomidine infusion

Experimental group

Description:

Subject will receive a bolus of0.5ug/kg intravenously over a period of 10-15 minutes, followed by an infusion of 0.2-0.7ug/kg/hr of drug.

Treatment:

Drug: Dexmedetomidine infusion