Intraoperative Ocular Pressure in Lumbar Spine Fusion Patients

Raised Ocular Pressure Clinical Trial

— IOP  

Official title:

Intraoperative Ocular Pressure in Lumbar Spine Fusion Patients

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02342288
• Other study ID #: 1409441146
• Status: Completed
• Phase: N/A
• First received: January 8, 2015
• Last updated: January 27, 2016
• Start date: July 2008
• Est. completion date: February 2014

Study information

• Verified date: January 2016
• Source: West Virginia University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

A rare but terrible complication of vision loss has been known to occur after surgery, including spine surgery. It is commonly thought that increased intraocular pressure (IOP) is one of the reasons for this rare vision loss. It has been shown that the prone position can increase the IOP, and that tilting the patient with the head down can also increase IOP. The investigators will be measuring IOP before, during, and after a posterior spine surgery to see if the investigators can influence the intraocular pressure with elevated head position change. Two groups will be studied: one group of patients will receive standard care with the head in neutral position, while the other group will have the head slightly elevated 10 degrees during prone spine surgery.

Description:

It has been reported that postoperative vision loss after lumbar surgery is increasing. It is an uncommon but devastating complication. One of the risk factors that has been reported is increased intraocular pressure (IOP), which may decrease perfusion pressure to the optic nerve. Intraocular pressure in anesthetized, prone spine patients has been studied with the head in neutral position. The prone position and duration of the procedure did increase the IOP. Our hypothesis is that adjusting the position of the head in space will alter the intraocular pressure, with an extended position decreasing IOP. This study is a, randomized, controlled design: neutral head position (standard care) or extended head position (intervention group). Patients who qualify for spinal fusion surgery and meet the inclusion criteria will be randomized to either the neutral (standard practice) or the intervention group.Randomization of patients will be computer generated.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 79
• Est. completion date: February 2014
• Est. primary completion date: February 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 80 Years

Eligibility

Inclusion Criteria:

• Patients undergoing elective lumbar spinal fusion surgery; ages 18-80

Exclusion Criteria:

• Less than 18 years of age

• Glaucoma, previous eye surgery, eye injury, or eye trauma, cervical myelopathy, prior cervical spine surgery, current neoplasm, patients who have neck pain with 10 degrees active extension.

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Subject)

Related Conditions & MeSH terms

• Raised Ocular Pressure

Intervention

Procedure:
• Head raised 10 degrees
Baseline measurement in seated position; anesthetization in the supine position. Prior to turning into the prone position, another measurement was taken. Five minutes after turning prone, a third IOP measurement was obtained. Head was raised to 10 degrees. After 5 minutes a fourth IOP measurement was performed. Repeat measurements were taken every 15 minutes until three sequential measurements were within plus or minus 3 mmHg of one another; thereafter, measurements were obtained every hour until end of case. A final measurement was taken after turning the patient supine and 5 minutes elapsed for equilibration.
• Head in neutral position
Baseline measurement in seated position; anesthetization in the supine position. Prior to turning into the prone position, another measurement was taken. Five minutes after turning prone, a third IOP measurement was obtained. After 5 minutes a fourth IOP measurement was performed. Repeat measurements were taken every 15 minutes until three sequential measurements were within plus or minus 3 mmHg of one another; thereafter, measurements were obtained every hour until end of case. A final measurement was taken after turning the patient supine and 5 minutes elapsed for equilibration.

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
West Virginia University

References & Publications (3)

Carey TW, Shaw KA, Weber ML, DeVine JG. Effect of the degree of reverse Trendelenburg position on intraocular pressure during prone spine surgery: a randomized controlled trial. Spine J. 2014 Sep 1;14(9):2118-26. doi: 10.1016/j.spinee.2013.12.025. Epub 2014 Jan 20. — View Citation

Ozcan MS, Praetel C, Bhatti MT, Gravenstein N, Mahla ME, Seubert CN. The effect of body inclination during prone positioning on intraocular pressure in awake volunteers: a comparison of two operating tables. Anesth Analg. 2004 Oct;99(4):1152-8, table of contents. — View Citation

Walick KS, Kragh JE Jr, Ward JA, Crawford JJ. Changes in intraocular pressure due to surgical positioning: studying potential risk for postoperative vision loss. Spine (Phila Pa 1976). 2007 Nov 1;32(23):2591-5. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in Intraoperative Ocular Pressure in Lumbar Spine Fusion Patients Head Raised 10 Degrees or Kept in Neutral Position	The objective is to determine if slight elevation of the head (10 degrees up from neutral) can decrease the IOP compared to remaining in neutral position (standard of care) for the entire surgery. The mean values for ? IOP measurements (i.e. two eye average maximum IOP - two eye average baseline IOP obtained at first prone measurement).	Prone; 5 minutes after head raised to 10 degrees; every 15 minutes; 1 hr until end of surgery	No
Secondary	Change and Correlations in Intraoperative Ocular Pressure in Lumbar Spine Fusion Patients	The secondary outcome is to evaluate factors (age, gender, duration of procedure, blood loss, intraoperative fluids, blood pressure, and carbon dioxide levels) looking for correlations with intraocular pressure changes.	prone; every 15 minutes; 1 hr until end of surgery	No