Intraocular Pressure and Optic Nerve Sheath Diameter Changes at Different PEEP Levels

Intraocular Pressure and Optic Nerve Sheath Diameter Changes at Different Positive End-expiratory Pressure Applications in Laparotomic Surgery

Status

Terminated

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03938402

Enrollment

Registered

2019-05-06

Start date

2019-07-01

Completion date

2020-12-31

Last updated

2021-12-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Intracranial Pressure, Intraocular Pressure, Positive End-expiratory Pressure

Keywords

Intraocular pressure, Optic nerve sheath diameter, Positive end-expiratory pressure

Brief summary

Positive end-expiratory pressure (PEEP) is sometimes used during perioperative period, as it has favourable effects on lung mechanics. Unfortunately, it has some negative effects on the patients, like increased intraabdominal, intrathoracic, intracranial and intraocular pressures. In this study the investigators aimed to investigate the effects of different PEEP levels on the patients' intraocular and intracranial pressures. Intraocular pressure will be measured by ocular tonometry, and intracranial pressure will be estimated by optic nerve sheath diameter measurement. The measurements will be performed in the operating room in the patients undergoing laparotomic surgery.

Interventions

OTHERPositive end-expiratory pressure

Different levels of positive end-expiratory pressure (i.e., 5, 10 and 15 cm H2O) will be applied to the groups.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

DIAGNOSTIC

Masking

SINGLE (Subject)

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Inclusion criteria

* Patients undergoing laparotomy for gastrointestinal surgery * American Society of Anesthesiologists (ASA) 1 or 2 physical status * Elective surgery

Exclusion criteria

* Patients with glaucoma * ASA 3 or over physical status * Emergency surgery

Design outcomes

Primary

Measure	Time frame	Description
Changes in intraocular pressure	Throughout the operation (usually about 1.5 hours).	The physiological value for intraocular pressure is 10-20 mm Hg. Changes in intraocular pressure will be observed throughout the surgery, as will its relationship with the positive end-expiratory pressure application.
Changes in optic nerve sheath diameter	Throughout the operation (usually about 1.5 hours).	Changes in optic nerve sheath diameter will be observed throughout the surgery, as will its relationship with the positive end-expiratory pressure application.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026