Effect of Compression Stockings on Cerebral Desaturation Events in Obese Patients Undergoing Shoulder Arthroscopy in the Beach Chair
Effect of Compression Stockings on Cerebral Desaturation Events in Obese Patients Undergoing Shoulder Arthroscopy in the Beach Chair
The study compares the effect of thigh high compression stockings on cerebral desaturation
 events in patients undergoing shoulder arthroscopy in the beach chair position with a BMI
 greater than or equal to 30.
On the day of surgery, enrolled patients whom have signed consent for participation in the
 study will be randomized to receive thigh high compression stockings with SCDs or SCDs alone.
 The importance of the investigation, proposed methodology, and potential risks of
 participation will be addressed. In the pre-operative holding area, a cerebral oximeter
 (INVOS 5100C, Covidien) will be placed on the skull as directed by the manufacturer. The
 sensors will be placed on the skull bilaterally in order to assess perfusion in both
 hemispheres. Cerebral oximeter is a non-invasive, transcutaneous tool that can be used to
 measure cerebral tissue oxygenation. The tool uses nearinfrared spectroscopy to measure the
 percentage of hemoglobin saturated with oxygen in the microcirculation of tissue within
 approximately 2-3cm below the skin. The technology is approved by the FDA in the anesthesia
 setting to monitor cerebral oxygenation and is commonly used in cardiothoracic surgery and
 its use has been validated in the surgical setting.11 A baseline cerebral tissue oxygen
 saturation (rSO2) will be recorded. All patients will be anesthetized using a standardized
 protocol. Once anesthesia has been induced, thigh high compression stockings will be applied
 to the appropriate group followed by SCDs. All patients in the study will wear sequential
 compression devices on both legs for thrombosis prophylaxis regardless of randomization. The
 patient will then be raised into the beach chair position and secured in the normal fashion
 and the planned surgery will begin. Intraoperative rSO2 data will be continuously recorded
 throughout the case. The system will be set to alarm when the rSO2 decreases greater than 20%
 from baseline. These events will be recorded throughout the case as CDEs. To avoid cerebral
 vascular injury, these events will be treated with a protocol by anesthesia including
 ephedrine, phenylephrine, and the patient may be returned to the supine position if needed.
 When surgery is complete, patients will be recovered in the post-anesthesia care unit. The
 study will be conducted at three facilities within the Loyola system: the Loyola Ambulatory
 Surgery Center at Oakbrook (LASCO), the Ambulatory Surgery Center at Loyola (ASC), and at
 Gottlieb Memorial Hospital (GMH). Personnel will include the attending surgeon, orthopaedic
 surgery residents, and anesthesia staff assigned to each case, all of whom will be fully
 educated on the study and protocols.
Inclusion Criteria:

 -  • All patient over age 18

 -  BMI > 30

 -  Undergoing shoulder arthroscopy in beach chair position

 Exclusion Criteria:

 -  • Age < 18 years

 -  BMI < 30

 -  Known and documented >90% occlusion of carotid artery

 -  Prior neck surgery

 -  Women who are pregnant