Cardiopulmonary Bypass, Intracranial Pressure, Open Heart Surgery, Optic Nerve Sheath Diameter
Conditions
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.
Detailed description
Several mechanisms during CPB-including inflammatory response, hemodilution, reperfusion injury, hypothermia-rewarming imbalances, and microembolism formation-can lead to increased intracranial pressure and cerebral edema. Ultrasonographic measurement of ONSD provides a noninvasive means of monitoring these changes. In this study, ONSD will be measured at different time points, while hemodynamic parameters, NIRS values, and arterial blood gas analyses will be recorded simultaneously. The primary objective is to evaluate changes in ONSD, and the secondary objective is to determine the potential impact of these changes on intracranial pressure.
Interventions
PROCEDUREUltrasonography of the Optic Nerve Sheath
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.
Sponsors
Medipol University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Inclusion criteria
* Adults aged 18-85 years * Scheduled for elective open-heart surgery with cardiopulmonary bypass * Provided written informed consent
Exclusion criteria
* Ocular or neurological complications related to diabetes * History of previous eye, brain, or thoracic surgery * Diagnosis of hydrocephalus, glaucoma, intracranial mass, or stroke
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Optic Nerve Sheath Diameter (ONSD) | 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). | Evaluation of ONSD changes measured by ultrasonography to assess potential alterations in intracranial pressure during cardiopulmonary bypass. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Central Venous Pressure (CVP) | From induction of anesthesia until the end of surgery, recorded simultaneously with OSD measurements. | Measurement of central venous pressure. |
| 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). | Analysis of arterial blood pH values |
| Mean Arterial Pressure (MAP) | From induction of anesthesia until the end of surgery, recorded simultaneously with OSD measurements. | Measurement of mean arterial pressure. |
| 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). | Analysis of blood lactate levels. |
| partial Pressure of Arterial Oxygen (PaO₂) | 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). | Analysis of partial pressure of arterial oxygen. |
| 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). | Analysis of partial pressure of arterial carbon dioxide. |
Countries
Turkey (Türkiye)
Outcome results
None listed