The Effect of Different Sevoflurane Concentrations on Intraocular Pressure in Patients Undergoing Ocular Surgery Under General Anesthesia

• ClinicalTrials.gov Identifier: NCT01575626
• Recruitment Status: Unknown
• First Posted: April 11, 2012
• Last Update Posted: April 11, 2012
• Sponsor: Tel-Aviv Sourasky Medical Center
• Information provided by (Responsible Party): Tel-Aviv Sourasky Medical Center

Tracking Information

• First Submitted Date: March 28, 2012
• First Posted Date: April 11, 2012
• Last Update Posted Date: April 11, 2012
• Study Start Date: May 2012
• Estimated Primary Completion Date: May 2013 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: April 10, 2012)

effect of different end-tidal sevoflurane concentrations on the IOP [ Time Frame: 1 year ]

To assess the effect of different end-tidal sevoflurane concentrations on the IOP in patients undergoing extraocular procedures, i.e. strabismus correction and tear duct probing and irrigation under general anesthesia.

• Original Primary Outcome Measures: Same as current
• Change History: No Changes Posted

Current Secondary Outcome Measures (submitted: April 10, 2012)

propofol vs. sevoflurane on IOP [ Time Frame: 1 year ]

To compare the influence of propofol vs. sevoflurane on IOP

• Original Secondary Outcome Measures: Same as current
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: The Effect of Different Sevoflurane Concentrations on Intraocular Pressure in Patients Undergoing Ocular Surgery Under General Anesthesia
• Official Title: Not Provided

Brief Summary

One important goal in anesthetic management during ocular surgery is to provide adequate control of intraocular pressure (IOP). An increase in IOP may be catastrophic in patients with glaucoma or a penetrating open-eye injury. There is an ongoing debate over the effect of anesthetic agents on the IOP. Anesthetic regimens in this surgical field commonly consist of short-acting anesthetic agents, such as propofol and sevoflurane, usually combined with short-acting analgesics, such as remifentanil. Both propofol and sevoflurane are known to reduce the IOP. To this end there is no data in the literature to support or disprove this finding.

Study Hypothesis Variations in the end-tidal sevoflurane concentrations have no significant effect on the IOP.

Detailed Description

One important goal in anesthetic management during ocular surgery is to provide adequate control of intraocular pressure (IOP). An increase in IOP may be catastrophic in patients with glaucoma or a penetrating open-eye injury. There is an ongoing debate over the effect of anesthetic agents on the IOP. Anesthetic regimens in this surgical field commonly consist of short-acting anesthetic agents, such as propofol and sevoflurane, usually combined with short-acting analgesics, such as remifentanil. Both propofol and sevoflurane are known to reduce the IOP. Previous studies have compared these two anesthetics protocols in order to determine which provides superior control of the IOP. Propofol produced significantly lower IOP measurements compared to sevoflurane (both combined with remifentanil), in cataract surgery, whereas in non-ophthalmic surgery propofol and sevoflurane caused a comparable decrease in IOP. Sevoflurane, an inhalational anesthetic, has a rapid onset of action faster recovery time and is also suitable for inhalation induction because it does not irritate the airway. A prospective randomized clinical trial compared the effects of ketamine and sevoflurane on IOP during the eight minutes after induction of anesthesia (in 2-minute intervals) in children with suspected or diagnosed glaucoma undergoing EUA. During these 8 minutes the IOP decreased significantly only in the sevoflurane group. This finding contradicted claims that measurements immediately after induction are relatively unaffected by anesthetics and suggested that variations in sevoflurane concentration do affect the IOP. Yoshitake et al showed that the remarkable reductions of IOP after inductions are probably caused by induction agents, suggesting that sevoflurane is a useful anesthetic for elderly patients receiving ophthalmic surgeries. To this end there is no data in the literature to support or disprove this finding.

Study Hypothesis Variations in the end-tidal sevoflurane concentrations have no significant effect on the IOP.

• Study Type: Interventional
• Study Phase: Not Applicable
• Study Design: Allocation: Randomized; Intervention Model: Parallel Assignment; Masking: None (Open Label)
• Condition: IOP Changes Due to Anesthesia (Healthy Patients)

Intervention

Drug: Sevoflurane

All active comparators of this study have the same intervention as mentioned ahead:

First IOP measurement will be performed just before anesthesia induction. Standard general anesthesia will be induced using propofol (5 mcg/ml) administered by target controlled infusion (TCI - Schnider model),fentanyl and rocuronium according to standard protocol of general anesthesia. The second IOP measurement will be performed just before tracheal intubation.

Following tracheal intubation, concentration of propofol will be decreased till 0 and anesthesia with sevoflurane will be started, followed by 3 more IOP measurements for different end-tidal sevoflurane concentrations (Consented patients will be randomly allocated to one of three groups as mentioned).

Total of 5 IOP measurements. IOP will be measured by the ophthalmologist via both TonoPen XL and Schioz devices.

Study Arms

• Active Comparator: first sevoflurane concentration
  patients will be given 3 different end-tidal sevoflurane concentrations in the following order: 0%, 7%, 4%
  Intervention: Drug: Sevoflurane
• Active Comparator: second sevoflurane concentration
  patients will be given 3 different end-tidal sevoflurane concentrations in the following order: 4%, 7%, 0%
  Intervention: Drug: Sevoflurane
• Active Comparator: third sevoflurane concentration
  patients will be given 3 different end-tidal sevoflurane concentrations in the following order: 7%, 4%, 0%
  Intervention: Drug: Sevoflurane
• Active Comparator: Propofol
  General anesthesia will be induced using propofol (5 mcg/ml) administered by target controlled infusion (TCI - Schnider model).Following tracheal intubation, concentration of propofol will be decreased till 0.
  Intervention: Drug: Sevoflurane

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Unknown status
• Estimated Enrollment (submitted: April 10, 2012): 30
• Original Estimated Enrollment: Same as current
• Study Completion Date: Not Provided
• Estimated Primary Completion Date: May 2013 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• The study will include both men and women over 18 years old undergoing elective surgery for strabismus correction or tear duct probing and irrigation under general anesthesia.

Exclusion Criteria:

• Patients with known allergies,
• adverse reaction or contraindication (of any other reason) to sevoflurane or remifentanil, or any other anesthetic drug,
• patients with pre-existing intra-ocular ophthalmic disease, or infection.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: Israel

Administrative Information

• NCT Number: NCT01575626
• Other Study ID Numbers: TASMC-12-IM-0011-CTIL
• Has Data Monitoring Committee: Not Provided
• U.S. FDA-regulated Product: Not Provided
• IPD Sharing Statement: Not Provided
• Responsible Party: Tel-Aviv Sourasky Medical Center
• Study Sponsor: Tel-Aviv Sourasky Medical Center
• Collaborators: Not Provided
• Investigators: Not Provided
• PRS Account: Tel-Aviv Sourasky Medical Center
• Verification Date: April 2012