Cerebral Oximetry and Post-Operative Delirium in Cardiac Surgery Patients
CCCF ePoster library. Mailhot T. 10/27/15; 117322; P63 Disclosure(s)(s): Quebec Nursing Intervention Research Network (Fonds de recherche du Québec - Santé)
Tanya Mailhot
Tanya Mailhot
Login now to access Regular content available to all registered users.

You may also access this content "anytime, anywhere" with the Free MULTILEARNING App for iOS and Android
Rate & Comment (0)

Topic: Retrospective or Prospective Cohort Study

Cerebral Oximetry and Post-Operative Delirium in Cardiac Surgery Patients

Tanya Mailhot, S. Cossette, J. Lambert, A. Cournoyer, A. Denault

Research Center, Université de Montréal / Montreal Heart Institute, Montreal, Canada | Research Center, Université de Montréal / Montreal Heart institute, Montreal, Canada | Biostatistics, Montreal Health Innovations Coordinating Center, Montreal, Canada | Emergency medicine, Université de Montréal, Montreal, Canada | Anesthesiology, Montreal Heart Institute, Montreal, Canada


Post-cardiac surgery delirium has been associated with decreased cerebral perfusion and is usually evaluated using an assessment scale that is based on observation of clinical manifestations of delirium, like the Confusion Assessment Method-ICU (CAM-ICU) (1). A promising non-invasive avenue, that does not present the limits associated with observation of clinical manifestations, is to detect oxygen imbalances using cerebral oximetry (rSO2) obtained with Near Infrared Spectroscopy (NIRS). Oximetry can also be measured at the peripheral level and combining both the cerebral and peripheral levels allows differentiation of cerebral imbalances secondary to systemic hypoperfusion. Low pre and peri-cardiac surgery cerebral rSO2 values have been associated with delirium. To date, the relationship between cerebral, peripheral rSO2 and delirium in post-cardiac surgery patients has not yet been reported.


In the present study, we assessed the relationship between rSO2 values and the occurrence and severity level of delirium. We hypothesized that higher cerebral rSO2 values would decrease the odd of delirium occurrence and be related to lower severity level of delirium while peripheral rSO2 values would not be related to delirium.

Methods: This observational study embedded in a pilot RCT was conducted in an intensive care unit (ICU) and surgery ward in a Canadian tertiary cardiology academic hospital. During three consecutive days after delirium onset, cerebral and peripheral rSO2 values were obtained using NIRS and delirium was assessed using the CAM-ICU and a delirium severity scale (Delirium Index). Potential covariates were also collected. The relationships between rSO2 values and occurrence and severity level of delirium were analyzed with a marginal model and linear mixed models respectively, while controlling for sociodemographic, clinical data and time.


We included 30 consecutive adults (19 males and 11 females) aged 75.29 (±7.88) who presented delirium following either coronary artery bypass grafting (n=12) or heart valve surgery (n=18). As hypothesized, higher cerebral rSO2 values decreased the odd of delirium occurrence (odds ratio (OR): 0.73) (confidence interval (CI): 0.635; 0.838, p ≤ 0.0001), while higher peripheral rSO2 did not (OR: 1.01, (CI): 0.872; 1.176, p = 0.871). Additionally, higher cerebral rSO2 values were related to lower severity level of delirium ((CI): 0.625; -0.242, p ≤ 0.0001) while peripheral rSO2 values where not ((CI): -0.322; 0.186, p=0.595). Due to lack of information, no power calculation was performed prior the study. However, having observed significant associations between oximetry and delirium, we may conclude that we had sufficient power to detect these important effects.


Since delirium and rSO2 obtained with NIRS are related, delirium assessment with NIRS stands out as an alternative that could be used at the bedside in ICUs to assess delirium, both in detecting its early manifestations and monitoring its progression. Other studies with larger sample should be conducted to validate these observations in other clienteles as cerebral rSO2 might be key in the search for biomarkers of delirium.

References: (1) Ely EW, Inouye SK, Bernard GR, Gordon S, Francis J, May L, Truman B, Speroff T, Gautam S, Margolin R et al: Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU). Jama 2001, 286(21):2703-2710.
    This eLearning portal is powered by:
    This eLearning portal is powered by MULTIEPORTAL
Anonymous User Privacy Preferences

Strictly Necessary Cookies (Always Active)

MULTILEARNING platforms and tools hereinafter referred as “MLG SOFTWARE” are provided to you as pure educational platforms/services requiring cookies to operate. In the case of the MLG SOFTWARE, cookies are essential for the Platform to function properly for the provision of education. If these cookies are disabled, a large subset of the functionality provided by the Platform will either be unavailable or cease to work as expected. The MLG SOFTWARE do not capture non-essential activities such as menu items and listings you click on or pages viewed.

Performance Cookies

Performance cookies are used to analyse how visitors use a website in order to provide a better user experience.

Save Settings