Measurement of Intraocular Pressure in Patients Undergoing Laminectomy in the Prone Position

Elazıg Fethi Sekin Sehir Hastanesi

Status: Not yet enrolling

Conditions: Prone Position; Intraocular Pressure; Laminectomy

Study type: Observational

Funder types: Other

Identifiers

NCT07067008

FSCH-SB-2024/07

Details and patient eligibility

About

Laminectomy surgeries, typically performed for lumbar disc herniation and spinal disorders, are often lengthy surgical procedures requiring patients to be in the prone position. While this position provides better visibility of the surgical field, it can lead to physiological changes in intraocular pressure (IOP) in anesthetized patients. An increase in IOP, though rare, has the potential to cause severe ocular complications such as postoperative vision loss (POVL), which is one of the most feared complications after spinal surgery.

One of the main mechanisms of IOP elevation in the prone position is the impediment of venous return in the head and neck region due to gravity, leading to an increase in episcleral venous pressure. Additionally, direct mechanical pressure on the face and globe can also increase IOP. Anesthesia management can also play a role in IOP dynamics by affecting intrathoracic pressure and venous return. This complex interaction necessitates careful monitoring of eye health in anesthetized patients in the prone position. Non-contact tonometers offer a non-invasive, rapid, and reliable method for IOP measurement. They are particularly advantageous for repeated measurements in anesthetized patients. This clinical study aims to evaluate changes in IOP using a non-contact tonometer in patients undergoing laminectomy in the prone position and to identify anesthesia- and patient-related factors influencing these changes. The data obtained will contribute to the development of anesthesia and positioning strategies aimed at reducing the risk of ocular complications.

Enrollment: 60 estimated patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients scheduled for laminectomy surgery under general anesthesia

Patients with ASA physical status I-II-III

Patients who can cooperate postoperatively

Patients without eye diseases or conditions affecting eye physiology (such as glaucoma)

Patients who have not undergone eye surgery

Patients who consent to participate in the study

Exclusion criteria

• Patients scheduled for laminectomy surgery but not receiving general anesthesia

Patients with ASA physical status IV-V

Patients who do not consent to participate in the study

Patients who cannot cooperate postoperatively

Patients with eye diseases or conditions affecting eye physiology (such as glaucoma)

Patients who have undergone eye surgery

Patients from whom consent cannot be obtained

Trial design

60 participants in 2 patient groups

Group 1 will include those with a BMI of 40 kg/m2 and above.

Group 2 will include those with a BMI below 40 kg/m2.