Ventilation Strategies, Anesthetic Techniques and Cerebral Oxygenation in the Beach Chair Position

This study is currently recruiting participants. (see Contacts and Locations)
Verified July 2013 by University of Michigan
Sponsor:
Information provided by (Responsible Party):
Paul Picton, University of Michigan
ClinicalTrials.gov Identifier:
NCT01535274
First received: February 9, 2012
Last updated: July 17, 2013
Last verified: July 2013
  Purpose

The seated or "beach chair" position during surgery and general anesthesia decreases brain oxygen levels and can result in stroke. As such, poor neurological outcome following beach chair positioning is a growing concern. In the proposed study the investigators test the hypothesis that changes in ventilation strategy and anesthetic technique can affect cerebral oxygenation in anesthetized patients in the beach chair position.


Condition Intervention
Stroke
Other: Inspired oxygen fraction / end tidal carbon dioxide

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Prevention
Official Title: The Influence of Basic Ventilation Strategies and Anesthetic Techniques on Cerebral Oxygenation in the Beach Chair Position

Resource links provided by NLM:


Further study details as provided by University of Michigan:

Primary Outcome Measures:
  • Change in regional cerebral oxygenation (rSO2) before and 5 minutes after each change in ventilation strategy [ Time Frame: 2 years. ] [ Designated as safety issue: Yes ]
    rSO2 will be recorded as a "snap shot." A mean value from right and left sides will be calculated for each patient at each study point.


Estimated Enrollment: 54
Study Start Date: September 2012
Estimated Study Completion Date: September 2014
Estimated Primary Completion Date: September 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Desflurane
Patients will receive general anesthesia with desflurane. Both arms have rSO2 measured and undergo identical changes in ventilation strategy.
Other: Inspired oxygen fraction / end tidal carbon dioxide

Following induction of anesthesia, FIO2 and minute ventilation will be sequentially adjusted to achieve:

  1. FIO2 30% (70% nitrogen), PETCO2 30mmHg - supine position.
  2. FIO2 30% (70% nitrogen), PETCO2 30mmHg - beach chair position.
  3. FIO2 100%, PETCO2 30mmHg - beach chair position.
  4. FIO2 100%, PETCO2 45mmHg - beach chair position.
  5. FIO2 30% (70% nitrogen), PETCO2 30mmHg - beach chair position.
Experimental: Propofol
Patients will receive total intravenous general anesthesia (TIVA) with propofol. Both have rSO2 measured and undergo identical changes in ventilation strategy.
Other: Inspired oxygen fraction / end tidal carbon dioxide

Following induction of anesthesia, FIO2 and minute ventilation will be sequentially adjusted to achieve:

  1. FIO2 30% (70% nitrogen), PETCO2 30mmHg - supine position.
  2. FIO2 30% (70% nitrogen), PETCO2 30mmHg - beach chair position.
  3. FIO2 100%, PETCO2 30mmHg - beach chair position.
  4. FIO2 100%, PETCO2 45mmHg - beach chair position.
  5. FIO2 30% (70% nitrogen), PETCO2 30mmHg - beach chair position.

Detailed Description:

This is a prospective cohort study with randomized nested design. Patients presenting for shoulder surgery will be randomized to receive desflurane or total intravenous anesthesia with propofol. Regional cerebral oxygenation will be measured using the INVOS 5100C monitor (Covidien, Boulder, CO). Depth of anesthesia will be maintained within a Bispectral Index range of 40-60. Following positioning, inspired oxygen fraction and minute ventilation will be sequentially adjusted. At each set point, regional cerebral oxygenation will be recorded and venous blood gas analysis performed. Statistical analysis will be repeated measures analysis of variance in which ventilation strategy is the within-subjects factor and anesthetic technique is the between-subjects factor; post hoc Tukey's correction will be used for multiple comparisons. If simple maneuvers of ventilation and anesthetic technique can prevent low brain oxygen levels, patient outcome may be improved.

  Eligibility

Ages Eligible for Study:   18 Years to 85 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • scheduled for elective arthroscopic shoulder surgery in the beach chair position under general anesthesia with supplemental interscalene block

Exclusion Criteria:

  • refusal to give consent
  • ineligible for interscalene block
  • history of cardiovascular disease
  • history of cerebrovascular disease
  • hypertension
  • respiratory failure
  • non-English speaker
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01535274

Contacts
Contact: Amy Shanks, MS 734-936-0063 amysha@med.umich.edu

Locations
United States, Michigan
University of Michigan Recruiting
Ann Arbor, Michigan, United States, 48109
Principal Investigator: Paul Picton, MB ChB         
Sub-Investigator: George A Mashour, MD PhD         
Sub-Investigator: Andrew Dering, MB BS         
Sub-Investigator: Bruce Miller, MD         
Sub-Investigator: Amy Shanks, MS         
Sponsors and Collaborators
University of Michigan
  More Information

No publications provided

Responsible Party: Paul Picton, Assistant Professor, University of Michigan
ClinicalTrials.gov Identifier: NCT01535274     History of Changes
Other Study ID Numbers: HUM00049747
Study First Received: February 9, 2012
Last Updated: July 17, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by University of Michigan:
Cerebral oxygenation
Beach chair position
General anesthetic technique
Inspired oxygen fraction
End tidal carbon dioxide

Additional relevant MeSH terms:
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on September 18, 2014