Evaluation of Optic Nerve Sheath Diameter Changes During Cardiopulmonary Bypass in Open Heart Surgery

NCT07253922 | Completed

• 1 other identifier: Medipol-OSKC-2025
• Study Type: observational
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

During cardiopulmonary bypass (CPB) in open-heart surgery, direct measurement of intracranial pressure is not feasible. Evaluation of the optic nerve sheath diameter (ONSD) by ultrasonography is considered a reliable method for predicting increases in intracranial pressure. This study aims to investigate changes in ONSD in patients undergoing open-heart surgery with CPB.

Conditions

Open Heart Surgery; Cardiopulmonary Bypass; Intracranial Pressure; Optic Nerve Sheath Diameter

Outcome Measures

Primary Outcomes (1)

• Change in Optic Nerve Sheath Diameter (ONSD)

  Evaluation of ONSD changes measured by ultrasonography to assess potential alterations in intracranial pressure during cardiopulmonary bypass.

  From tracheal intubation (baseline) until the end of surgery (approximately 4-6 hours); measurements at six predefined time points (post-intubation, CPB initiation, 15 min, 45 min, 15 min after CPB termination, end of surgery).

Secondary Outcomes (6)

• Mean Arterial Pressure (MAP)

  From induction of anesthesia until the end of surgery, recorded simultaneously with OSD measurements.

• Central Venous Pressure (CVP)

  From induction of anesthesia until the end of surgery, recorded simultaneously with OSD measurements.

• Arterial Blood pH

  From tracheal intubation (baseline) until the end of surgery (approximately 4-6 hours); measurements at six predefined time points (post-intubation, CPB initiation, 15 min, 45 min, 15 min after CPB termination, end of surgery).

• Partial Pressure of Arterial Carbon Dioxide (PaCO₂)

  From tracheal intubation (baseline) until the end of surgery (approximately 4-6 hours); measurements at six predefined time points (post-intubation, CPB initiation, 15 min, 45 min, 15 min after CPB termination, end of surgery).

• Lactate

  From tracheal intubation (baseline) until the end of surgery (approximately 4-6 hours); measurements at six predefined time points (post-intubation, CPB initiation, 15 min, 45 min, 15 min after CPB termination, end of surgery).

Study Arms (1)

Study Cohort

Adult patients (18-85 years) undergoing elective open-heart surgery with cardiopulmonary bypass. Optic nerve sheath diameter (ONSD) will be measured by ultrasonography at predefined time points, along with hemodynamic parameters, NIRS values, and arterial blood gas analyses.

Procedure: Ultrasonography of the Optic Nerve Sheath

Interventions

Ultrasonography of the Optic Nerve Sheath PROCEDURE

Ultrasonographic measurement of the optic nerve sheath diameter (ONSD) will be performed using a 7.5 MHz linear probe. Measurements will be taken 3 mm behind the globe in both transverse and sagittal planes, three times for each eye, and the average value will be recorded at predefined time points during cardiopulmonary bypass.

Study Cohort

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients (18-85 years) undergoing elective open-heart surgery with cardiopulmonary bypass at Istanbul Medipol University Hospital, who meet inclusion criteria and provide written informed consent.

You may qualify if:

• Adults aged 18-85 years
• Scheduled for elective open-heart surgery with cardiopulmonary bypass
• Provided written informed consent

You may not qualify if:

• Ocular or neurological complications related to diabetes
• History of previous eye, brain, or thoracic surgery
• Diagnosis of hydrocephalus, glaucoma, intracranial mass, or stroke

Sponsors & Collaborators

• Medipol University: lead

Study Sites (1)

Medipol University

Istanbul, Turkey (Türkiye)

Location

Related Publications (3)

• Omur B, Ciftci B, Karaaslan P. Evaluation of optic nerve sheath diameter in patients undergoing laparoscopic surgery in the Trendelenburg position: a prospective observational study. Ann Saudi Med. 2024 Sep-Oct;44(5):319-328. doi: 10.5144/0256-4947.2024.319. Epub 2024 Oct 3.

  PMID: 39368121 BACKGROUND

• Writing Group Members; Mozaffarian D, Benjamin EJ, Go AS, Arnett DK, Blaha MJ, Cushman M, Das SR, de Ferranti S, Despres JP, Fullerton HJ, Howard VJ, Huffman MD, Isasi CR, Jimenez MC, Judd SE, Kissela BM, Lichtman JH, Lisabeth LD, Liu S, Mackey RH, Magid DJ, McGuire DK, Mohler ER 3rd, Moy CS, Muntner P, Mussolino ME, Nasir K, Neumar RW, Nichol G, Palaniappan L, Pandey DK, Reeves MJ, Rodriguez CJ, Rosamond W, Sorlie PD, Stein J, Towfighi A, Turan TN, Virani SS, Woo D, Yeh RW, Turner MB; American Heart Association Statistics Committee; Stroke Statistics Subcommittee. Heart Disease and Stroke Statistics-2016 Update: A Report From the American Heart Association. Circulation. 2016 Jan 26;133(4):e38-360. doi: 10.1161/CIR.0000000000000350. Epub 2015 Dec 16. No abstract available.

  PMID: 26673558 BACKGROUND

• Ismail A, Semien G, Sharma S, Collier SA, Miskolczi SY. Cardiopulmonary Bypass. 2024 Aug 12. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK482190/

  PMID: 29489210 BACKGROUND

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Anesthesiology

Study Record Dates

• First Submitted: August 22, 2025
• First Posted: November 28, 2025
• Study Start: June 10, 2025
• Primary Completion: October 10, 2025
• Study Completion: November 25, 2025
• Last Updated: November 28, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)