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09:54
A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Significant decrease of cerebral oxygen saturation during single-lung ventilation measured using absolute oximetry.
T M Hemmerling1, M C Bluteau, R Kazan
1Department of Anaesthesiology, ITAG (Intelligent Technology in Anaesthesia Group), Montreal General Hospital, McGill University, 1650 Cedar Avenue, Montreal, Canada H3G 1B7.
British Journal of Anaesthesia
|October 7, 2008
Summary
Single-lung ventilation during thoracic surgery significantly reduces cerebral oxygen saturation (SctO2) in most patients. Standard monitoring like peripheral oxygen saturation is insufficient to detect these critical drops in brain oxygen levels.
Area of Science:
- Anesthesiology
- Cardiopulmonary Physiology
Background:
- Single-lung ventilation (SLV) during thoracic surgery induces significant cardiopulmonary disturbances.
- Cerebral oxygen saturation (SctO2) monitoring is crucial during such procedures.
Purpose of the Study:
- To determine the incidence and magnitude of SctO2 decrease during SLV.
- To assess the correlation between SctO2 changes and standard clinical parameters.
Main Methods:
- 20 patients undergoing thoracic surgery requiring >1 hour of SLV were monitored.
- Absolute cerebral oximetry (FORESIGHT) measured SctO2 every 5 minutes.
- Standard monitoring, bispectral index, and blood gas analysis were also performed.
Main Results:
- SctO2 decreased significantly during SLV, with 70% of patients experiencing >20% reduction.
- The minimum SctO2 was 63% during SLV, recovering to 71% post-extubation.
- No correlation was found between SctO2 decrease and arterial pressure, blood loss, or PaO2.
Conclusions:
- Thoracic surgery with SLV is associated with substantial SctO2 reduction in most patients.
- Standard parameters like peripheral oxygen saturation and PaO2 are inadequate for detecting significant cerebral desaturation during SLV.
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