Neuro-Ox 2018: Assessment of Cerebral Oxygenation Under Three Clinically Relevant Conditions
Study Details
Study Description
Brief Summary
This is a prospective observational study, consisting of 3 substudies carried out during elective neurosurgery under general anaesthesia. Each participant will take part in all 3 substudies. First, the capability of Near Infra Red Spectroscopy (NIRS) to measure the brain oxygenation is examined. A NIRS-electrode is placed on forehead skin, on the skull, and on dura. Secondly, a small dose of Phenylephrine is given, and the brain oxygenation is measured by a Clark-electrode and a NIRS-electrode, to see how Phenylephrine affects these measurements. In the third substudy, the brain oxygenations' (NIRS and Licox) response to an inspired oxygen fraction of 0.30 vs. 0.80 is investigated.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Other: One strategy for all enrolled patients: All patients will participate in three substudies, in which they also act as controls, with exposure to the same three interventions: 1) NIRS-measurement on skin, skull and dura, 2) Phenylephrine 0.1 mg iv., and 3) inspired oxygen fraction of 0.3 vs. 0.8 |
Device: NIRS measurements on skin, skull and dura
During a neurosurgical procedure, we will measure the brain oxygenation with a NIRS-electrode, first on forehead skin, then on the skull and finally directly on dura.
Drug: Phenylephrine's effect on brain oxygenation
With a Clark-electrode (Licox(R)) in the white matter and a NIRS-electrode on the forehead skin, we will give a small dose (0.1 mg iv.) Phenylephrine.
Drug: Normal vs. high inspired oxygen
By the end of the neurosurgical procedure, still with a Clark-electrode in the white matter and a NIRS-electrode on forehead skin, we will change the inspired oxygen fraction from 0.3 to 0.8.
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Outcome Measures
Primary Outcome Measures
- ScO2 (NIRS-measured cerebral oxygen saturation) [During surgical procedure]
Difference in ScO2 between dura and skin (Primary analysis for substudy 1)
Secondary Outcome Measures
- PBrO2 (Partial pressure of brain tissue oxygen) [During surgical procedure]
Cerebral oxygenation, measured by a Clark-electrode (Licox (R)) (Primary outcome measure for substudy 2)
- PBrO2 (Partial pressure of brain tissue oxygen) ['Normoxia' is induced with FiO2 = 0.30 for 5 minutes, and then changed to 'Hyperoxia' with FiO2 = 0.80 for the subsequent 5 minutes, while registering the Licox-signal.]
Cerebral oxygenation during inspired oxygen fraction 0.80 vs. 0.30 (Primary outcome for substudy 3)
- ScO2 (NIRS-measured cerebral oxygen saturation) [Measurements will be performed as the surgeon exposes the skull.]
Difference in ScO2 between dura and skull, and between skull and skin (this will be the secondary analyses of substudy 1)
- ScO2 (NIRS-measured cerebral oxygenation) [NIRS signal is obtained continuously during the Phenylephrine intervention]
NIRS-signal during Phenylephrine intervention (this will be the secondary outcome of substudy 2)
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Adult (>18 years) patients
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Elective craniotomy
Exclusion Criteria:
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Repeat craniotomy
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Preoperative hypotension (defined as systolic blood pressure below 110 mmHg)
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Preoperative hypoxia (defined as peripheral oxygen saturation (SpO2) < 90% without oxygen supplementation before surgery)
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No negative pregnancy test for women <50 years.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Rigshospitalet | Copenhagen | Denmark | 2100 |
Sponsors and Collaborators
- University Hospital Bispebjerg and Frederiksberg
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- Neuro-Ox 2018