CE: ; MCC/300618; Total nos of Pages: 7;

MCC 300618

REVIEW

C URRENT
OPINION Cerebral oximetry in high-risk surgical patients:
where are we?
Rosalia Navarro-Perez a, Nekane Romero-García b, Camilla Paolessi c,
Chiara Robba c and Rafael Badenes b

Purpose of review
This review aims to summarize the latest evidence on the role of near-infrared spectroscopy (NIRS) in
monitoring cerebral oxygenation in high-risk surgical patients, including both cardiac and noncardiac
surgeries, and to present a new algorithm for its application.
Recent findings
NIRS effectively measures brain oxygen saturation noninvasively, proving valuable in cardiac surgeries to
reduce neurological complications, though its impact on nonneurological outcomes is less clear. In
noncardiac surgeries, NIRS can help prevent complications like postoperative cognitive dysfunction,
particularly in high-risk and major surgeries. Studies highlight the variability of cerebral oxygenation
impacts based on surgical positions, with mixed results in positions like the beach chair and sitting
positions. A structured algorithm for managing cerebral desaturation has been proposed to optimize
outcomes by addressing multiple factors contributing to blood oxygen content and delivery.
Summary
Despite its limitations, including spatial resolution and interindividual variability, NIRS is a useful tool for
intraoperative cerebral monitoring. Further studies are needed to confirm its broader applicability in
noncardiac surgeries, but current evidence supports its role in reducing postoperative complications
especially in cardiac surgeries.
Keywords
cardiac surgery, cerebral oxygenation, high-risk surgical patients, near-infrared spectroscopy, noncardiac
surgery, postoperative cognitive dysfunction

INTRODUCTION The question has been raised whether cerebral

The brain is the most metabolically active organ oximetry should be universally used during surgery,
in the human body, a primary site of action for given its capability to detect potentially catastrophic
anaesthetic agents, and is at risk for dysfunction perioperative events [1]. Despite this potential,
during both intra-operative and postoperative there is a lack of high-quality evidence to guide
periods [1]. Advances in aesthetic care have signifi- clinicians in using cerebral oximetry to reduce neu-
cantly reduced perioperative mortality and morbid- rocognitive complications after surgery, especially
ity in the developed world, even as the baseline risk in noncardiac patients [1]. Notably, other standard
of patients undergoing surgical procedures has monitoring modalities, such as pulse oximetry, also
increased [2]. lack scientific proof of outcome benefits [1].
Ensuring adequate brain function is the
a
paramount objective of the anaesthetic process [3]. Anesthesia Department, Clínico San Carlos University Hospital,
Madrid, bDepartment Anesthesiology and Critical Care, Hospital Clínic
However, brain monitoring poses a significant
Universitari de Valencia, University of Valencia, Valencia, Spain and
challenge to anaesthesiologist’s because of either c
Anesthesia and Intensive Care Department, IRCCS Policlinico San
high complexity, such as with raw electroencepha- Martino Hospital, Genova, Italy
lography (EEG), or invasiveness, as in the case of brain Correspondence to Dr Rosalia Navarro-Perez, Clínico San Carlos Uni-
&
tissue oxygen tension (PbtO2) [4 ]. In contrast, cere- versity Hospital, Calle Profesor Martín Lagos, s/n, 28040 Madrid, Spain.
bral oximeters are noninvasive, continuous, and E-mail: rnavarrop@salud.madrid.org
intuitive devices that accurately depict the balance Curr Opin Crit Care 2024, 30:000–000
between brain oxygen delivery and consumption [5]. DOI:10.1097/MCC.0000000000001204

1070-5295 Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved. www.co-criticalcare.com

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

The surgical patient

and demand. This balance is primarily influenced by

KEY POINTS factors such as cerebral blood flow (CBF), oxygen
content, and metabolic rate. Disruptions in this
 NIRS measures brain oxygen saturation noninvasively,
balance, because of anaesthesia or surgical proce-
but its value is better when focusing on changes from
baseline values because of limitations like spatial dures, can lead to cerebral hypoxia, highlighting the
resolution and interindividual variability. importance of real-time monitoring with NIRS.
Despite its utility, cerebral oximetry has several
 NIRS is used in cardiac surgery to reduce neurological limitations. Spatial resolution is restricted, as
complications, though its impact on nonneurological
approximately 15% of the light signal is reflected
outcomes remains unclear.
from overlying extracerebral tissue; this is particu-
 NIRS in noncardiac surgeries may help prevent larly relevant in the presence of extracerebral hae-
postoperative complications like cognitive dysfunction, matoma [6]. Physiological values for NIRS have been
especially in major surgeries and high-risk patients. defined assuming a cortical arterial/venous blood
 The impact of surgical positions on cerebral ratio of 30/70% according to PET imaging [1]. How-
oxygenation varies, with some positions showing ever, recent studies have found significant interin-
significant rSO2 drops but low incidence of dividual variation, highlighting the risk of using a
severe outcomes. universal fixed ratio [8]. Nonheme chromophores,
 A structured algorithm for managing cerebral such as bilirubin, may also alter NIRS reading [9].
desaturation optimizes blood oxygen content and Given these considerations, baseline rSO2 values
delivery to standardize NIRS use and improve vary between individuals, thus the changes in
patient outcomes. rSO2 relative to baseline (e.g. preinduction of anaes-
thesia) measurements may be more relevant to
&
guide therapy than absolute values [1,4 ]. Baseline
The aim of this review is to summarize the latest rSO2 values should be obtained before preoxygenat-
evidence on the role of cerebral oximetry in high- ing for induction of general anaesthesia, as supple-
risk surgical patients and to present a new algorithm mental oxygen increases rSO2 [1,10].
for its application. We aim to present the funda- Cerebral desaturation is defined as a decrease in
mentals of cerebral oximetry and provide an over- either absolute or patients’ baseline regional cere-
view of its key advantages during the perioperative bral oxygen saturation value, although different
period in both cardiac and noncardiac patients. threshold values have been used across studies
&&
[11 ,12–18]. Both the depth and duration of rSO2
desaturations are important to be assessed [19].
FUNDAMENTALS OF CEREBRAL Multiple cerebral oximeters are commercially
OXIMETRY available, all of which have technical differences that
Cerebral oximetry is based on near-infrared spectro- make them noninterchangeable. Therefore, caution
scopy (NIRS) technology to measure oxygen is recommended when comparing cerebral oximetry
saturation in the brain parenchyma [6]. NIRS is values between different manufacturers [1].
cost-effective, requiring only a monitor connected Once a firm understanding of NIRS is estab-
to oximeter probes on adhesive pads placed on the lished and the technical limitations of cerebral
patient’s scalp over the frontal lobe. These probes oximetry are considered, clinicians can effectively
contain a fibre optic light source that emits infrared use these devices to optimize patient care [1].
light, which travels across the skull, and detectors
that capture the reflected light. The absorption
spectrum varies according to the oxygenation status CEREBRAL OXIMETRY IN CARDIAC
of haemoglobin (Hb), with higher wavelengths SURGERY
corresponding to oxygenated Hb (700–1150 nm). Neurological and nonneurological complications
Similar to conventional pulse oximeters, Lam- constitute a major concern in cardiac surgery because
bert–Beer’s Law is used to calculate tissue concen- of the frequent imbalance in oxygen demand and
&&
tration of oxygenated and de-oxygenated Hb [7]. supply to vital organs [20 ]. NIRS has been intro-
Although pulse oximetry determines oxygen satu- duced in cardiac surgery to monitor preoperative
ration in arterial blood, cerebral oximetry values baseline rSO2 and detect intraoperative cerebral
originate from a mixture of venous, capillary, and desaturations. This monitoring aids in identifying
arterial blood, resulting in normal values ranging patients at higher risk of adverse outcomes, facilitat-
between 60 and 75% [1]. Cerebral oximetry meas- ing timely interventions to correct cerebral hypoxia
ures regional oxygen saturation (rSO2), which and potentially reducing morbidity, mortality, and
&& &
reflects the balance between cerebral oxygen supply associated costs [20 ,21,22 ]. Postoperative NIRS

2 www.co-criticalcare.com Volume 30  Number 00  Month 2024

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

Cerebral oximetry in high-risk surgical patients Navarro-Perez et al.

monitoring can also detect neurocognitive disorders neurocognitive dysfunction or biomarkers of organ
that might remain undetected through conventional damage.
clinical assessments and neurologic examinations In summary, despite current literature suggest-
[23]. ing that rSO2 decrements from preoperative baseline
Neurological morbidity represents one of the are associated with adverse outcomes, the lack of
most common complications following cardiac sur- clear rSO2 threshold values, varying methodologies,
gery, encompassing conditions like postoperative and single-centre study designs complicate drawing
cognitive decline (POCD), delirium (POD), and firm conclusions. Nonetheless, there is a consensus
stroke, with prevalence rates ranging approximately on using cerebral oximetry to guide the manage-
from 25 to 50, 30, and 1–3%, respectively [24]. ment of acute cerebral hypoperfusion during cardiac
Concerning the incidence of delirium, it has been surgery, with a recommendation for using intrao-
suggested that a baseline rSO2 50% or less is more perative cerebral oximetry indexed to preinduction
predictive of POD than relative changes in cerebral baseline [1]. Studies also suggest that low preoper-
oximetry [16]. Chiong et al. [20 ] demonstrated that
&&
ative rSO2 is associated with a higher probability of
monitoring and correcting cerebral desaturation mortality and postoperative delirium, underscoring
during surgeries involving cardiopulmonary bypass its potential for preoperative risk stratification [1].
reduced the incidence of POCD. However, Moore
et al. [25 ] found insufficient evidence to support
&

improved neurocognitive outcomes with rSO2 mon- NEAR-INFRARED SPECTROSCOPY IN

itoring. Further questions have emerged regarding NONCARDIAC SURGERY
the impact of targeted rSO2 optimization on patient NIRS is commonly used to monitor rSO2 during
outcomes. A randomized controlled trial [26] cardiac surgery, but its application in noncardiac
reported better memory scores in the intervention surgery is less established [33]. However, cerebral
group at 6 months but no significant differences in desaturations appear to be more frequent than
other cognitive domains or perioperative outcomes. expected, especially in major noncardiac surgery
Harilall et al. [21] observed lower postoperative and in high-risk surgical patients [33,34]. A system-
S100B concentrations in the intervention group atic review found that while rSO2 is typically main-
following the Murkin algorithm. Additionally, tained in minor noncardiac surgeries, it is reduced
Semrau et al. [27] found inconsistent relationships during thoracic surgery involving single lung
between rSO2 and neurological outcomes, question- ventilation, major abdominal surgery, hip surgery,
ing the benefit of targeted cerebral oximetry. and laparoscopic surgery with the patient placed in
Cerebral NIRS has been also investigated for its anti-Trendelenburg position. Shoulder arthroscopy
potential to reflect inadequate perfusion in other in the beach chair position and carotid artery endar-
vital organs [28]. However, cerebral autoregulation, terectomy (CAE) with clamped internal carotid artery
which ensures stable brain blood flow and oxygen also cause pronounced cerebral desaturation [33].
delivery even in low cardiac output states, might be Although cerebral deoxygenation, as determined
a confounding factor in predicting organ damage by NIRS, seems to predict postoperative complica-
[29]. Numerous studies have failed to establish tions following cardiac surgery [34], there is less
significant correlation between NIRS and nonneuro- literature for noncardiac surgery. Several studies
&&
logical outcomes such as acute kidney injury (AKI), [11 ,33–35] reported that noncardiac surgical
&& && &
myocardial infarction, mortality rate [11 ,20 ,25 , patients who experienced cerebral desaturation had
&& &&
30], duration of mechanical ventilation [11 ,20 ], a higher risk of developing postoperative neurologic
&& &&
length of hospital or ICU stay [11 ,20 ,30], fre- complications, particularly POCD. Additionally, a
quency of transfusions, and reoperation rates [30]. correlation was found between cerebral desaturation
However, integrating NIRS variability with clinical and increased length of hospital stay, especially in
data has shown promise in predicting AKI in one elderly patients [34]. Monk et al. [36] demonstrated
study involving critically ill children [29], and a that POCD after major noncardiac surgeries was asso-
retrospective analysis indicated a correlation ciated with an increased mortality rate.
between low intraoperative mean rSO2 values and Low preoperative rSO2 is linked to more post-
&
postoperative AKI [31 ]. Additionally, NIRS also pro- operative complications after cardiac surgery, but its
vides insights into perioperative haemoglobin con- broader potential for paranaesthesia risk assessment
is still unclear. Baehner et al. [37 ] found no asso-
&&
centration changes, enabling assessment of
anaemia-related oxygenation impairment and guid- ciation between preoperative rSO2 and postopera-
ing transfusion decisions [32 ]. Yet, Rogers et al. [18]
&&
tive complications in high-risk noncardiac surgery,
found no evidence supporting personalized NIRS- likely due to NIRS’s insufficient discriminatory
based algorithms, for optimizing rSO2 to reduce power and individual variability in rSO2 values.

1070-5295 Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved. www.co-criticalcare.com 3

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

The surgical patient

However, Wen et al. [38] observed that saturation of postoperative cognitive dysfunction and other
levels 68% or less carried a positive likelihood ratio complications.
of 2.2 for death or severe morbidity. Then, more
studies are required to confirm if cerebral oximetry
can be used effectively in noncardiac surgeries to CEREBRAL OXIMETRY-BASED
stratify the risk of patients. MANAGEMENT IN HIGH-RISK SURGICAL
Focusing on the types of noncardiac surgery PATIENT: A PROPOSED ALGORITHM
where cerebral oxygenation may be challenged, The body of evidence suggests that cerebral oxime-
we can highlight surgeries involving the anti-Tren- try may have the potential to improve patient out-
delenburg body position. Studies on this position, comes, provided a goal-directed management is
&
particularly the beach chair position, have shown applied [51,52 ,53–55]. Therefore, a need for shared
mixed results regarding significant falls in rSO2. To protocols regarding cerebral desaturation exists.
provide clarity, the Anesthesia Patient Safety Foun- The proposed algorithm (Fig. 1) describes the
dation (APSF) conducted a study that found lower protocol used for differential diagnosis and treat-
rSO2 in beach chair position compared with the ment of a decrease in unilateral or bilateral NIRS
lateral decubitus position but no associated wors- values in the perioperative environment, which was
ened outcomes [39]. Moreover, the incidence of elaborated based on original works in the field
cerebral hypoxemia was found to be low. Therefore, [5,56].
routine monitoring of rSO2 in these patients may Once mechanical factors have been excluded,
not be justified [19]. In neurosurgery, comparing the classic types of brain hypoxia as described by
sitting position with the prone position used in Siggaard–Andersen et al. [57] have to be considered.
posterior fossa surgeries also shows varied effects. The optimization of factors contributing to blood
Dilmen et al. [40 ] showed that while sitting position
&
oxygen content and delivery is performed sequen-
reduces CBF and rSO2, prone position only causes tially [58]. If hypoxia of ischemic type is suspected,
slight reductions in cerebral oxygenation, making both the determinants of cardiac output (preload,
prone position considered safer for spinal surgery. contractility, afterload, heart rate) and regulators of
However, Schramm et al. [41] found that cerebral microcirculation (pCO2, pH, temperature) should
oxygenation was slightly reduced in patients in both be assessed.
positions, with no significant differences between By following this algorithm, clinicians can
the groups. systematically manage intraoperative cerebral
Monitoring cerebral oxygenation during CAE is desaturation, potentially improving postoperative
important because of the risk of hypoxemic stroke, outcomes [1,59].
yet cerebral oximetry is not an established essential
monitor [19]. A current review found that a 20%
decrease from baseline in rSO2 has low sensitivity CONCLUSION
and high specificity for detecting intra-operative Cerebral oximetry using near-infrared spectroscopy
ischemia [42]. However, there is no consensus on is a valuable tool for monitoring brain oxygenation
the threshold decrease indicating the need for inter- during surgery, particularly in high-risk cardiac and
ventions like carotid shunt placement [43], so many noncardiac procedures. In cardiac surgeries, cerebral
centres use rSO2 monitoring to guide cardiovascular oximetry has demonstrated potential in predicting
management rather than as a direct intervention and mitigating neurological complications, though
indicator for shunt placement [19]. its impact on nonneurological outcomes remains
Following thoracic, major orthopaedic, and uncertain. In noncardiac surgeries, emerging evi-
abdominal surgery, the occurrence of POCD might dence indicates that cerebral desaturation is linked
be related to intraoperative cerebral desaturation to postoperative cognitive dysfunction and other
[33]. Several studies show a high incidence of complications, especially in high-risk patients and
rSO2 decrease measured by NIRS during thoracic those undergoing major surgeries. Introducing
surgery [44–46] and abdominal surgery [47–49]. structured algorithms for managing cerebral
Following surgery for hip fracture, patients with desaturation can enhance the effectiveness of NIRS
POCD have lower intraoperative rSO2 compared monitoring. The proposed algorithm highlights a
with non-POCD patients [34,50]. systematic approach to optimize high-risk surgical
In summary, although more studies are needed, patient outcomes by addressing potential causes of
current evidence suggests that monitoring cerebral brain hypoxia and guiding timely interventions.
oxygenation with NIRS in major noncardiac surgery Future research should focus on validating these
is important. Avoiding intraoperative cerebral approaches and establishing clear guidelines for
desaturation has advantages in reducing the risk broader application in surgical practice.

4 www.co-criticalcare.com Volume 30  Number 00  Month 2024

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

Cerebral oximetry in high-risk surgical patients Navarro-Perez et al.

FIGURE 1. Proposed algorithm for management of cerebral desaturation in high-risk surgical patients. Adapted with
permission from Badenes et al. [5] and Denault et al. [56].

3. Shander A, Lobel GP, Mathews DM. Brain monitoring and the depth of
Acknowledgements anesthesia: another Goldilocks dilemma. Anesth Analg 2018; 126:705–709.
None. 4. Romagnoli S, Lobo FA, Picetti E, et al. Noninvasive technology for brain
& monitoring: definition and meaning of the principal parameters for the Inter-
national PRactice On TEChnology neuro-moniToring group (I-PROTECT).
Financial support and sponsorship J Clin Monit Comput 2024; 38:827–845.
The I-PROTECT group presents this document with the aim of reviewing and
None. standardizing the noninvasive tools for brain monitoring (electroencephalography,
NIRS, transcranial Doppler, and pupillometry) in anaesthesia and intensive care
practices.
Conflicts of interest 5. Badenes R, Gouvea Bogossian E, Chisbert V, et al. The role of noninvasive
There are no conflicts of interest. brain oximetry in adult critically ill patients without primary nonanoxic brain
injury. Minerva Anestesiol 2021; 87:1226–1238.
6. Murkin JM, Arango M. Near-infrared spectroscopy as an index of brain and
tissue oxygenation. Br J Anaesth 2009; 103 Suppl 1:i3–i13.
REFERENCES AND RECOMMENDED 7. Tosh W, Patteril M. Cerebral oximetry. BJA Educ 2016; 16:417–421.
8. Watzman HM, Kurth CD, Montenegro LM, et al. Arterial and venous contribu-
READING tions to near-infrared cerebral oximetry. Anesthesiology 2000; 93:947–953.
Papers of particular interest, published within the annual period of review, have 9. Madsen PL, Skak C, Rasmussen A, Secher NH. Interference of cerebral near-
been highlighted as: infrared oximetry in patients with icterus. Anesth Analg 2000; 90:489–493.
& of special interest 10. Kim D-H, Kwak YL, Nam SH, et al. Assessment of cerebral oxygen supply-
&& of outstanding interest
demand balance by near-infrared spectroscopy during induction of an-
esthesia in patients undergoing coronary artery bypass graft surgery:
1. Thiele RH, Shaw AD, Bartels K, et al., Perioperative Quality Initiative (POQI) 6 comparison of midazolam with propofol. Korean J Anesthesiol 2009;
Workgroup. American society for enhanced recovery and perioperative 57:428–433.
quality initiative joint consensus statement on the role of neuromonitoring 11. Wong ZZ, Chiong XH, Chaw SH, et al. The use of cerebral oximetry in surgery:
in perioperative outcomes: cerebral near-infrared spectroscopy. Anesth Analg && a systematic review and meta-analysis of randomized controlled trials.
2020; 131:1444–1455. J Cardiothorac Vasc Anesth 2022; 36:2002–2011.
2. Bose S, Talmor D. Who is a high-risk surgical patient? Curr Opin Crit Care A systematic review and meta-analysis of 17 RCTs on the use of cerebral oximetry
2018; 24:547–553. in both cardiac and noncardiac surgery, with focus on neurological complications.

1070-5295 Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved. www.co-criticalcare.com 5

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

The surgical patient

12. Cox RM, Jamgochian GC, Nicholson K, et al. The effectiveness of cerebral 34. Sørensen H, Grocott HP, Secher NH. Near infrared spectroscopy for frontal
oxygenation monitoring during arthroscopic shoulder surgery in the beach lobe oxygenation during nonvascular abdominal surgery. Clin Physiol Funct
chair position: a randomized blinded study. J Shoulder Elbow Surg 2018; Imaging 2016; 36:427–435.
27:692–700. 35. Wang X, Feng K, Liu H, et al. Regional cerebral oxygen saturation and
13. Deschamps A, Lambert J, Couture P, et al. Reversal of decreases in cerebral postoperative delirium in endovascular surgery: a prospective cohort study.
saturation in high-risk cardiac surgery. J Cardiothorac Vasc Anesth 2013; Trials 2019; 20:504.
27:1260–1266. 36. Monk TG, Weldon BC, Garvan CW, et al. Predictors of cognitive dysfunction
14. Deschamps A, Hall R, Grocott H, et al. Cerebral oximetry monitoring to after major noncardiac surgery. Anesthesiology 2008; 108:18–30.
maintain normal cerebral oxygen saturation during high-risk cardiac surgery a 37. Baehner T, Perlewitz O, Ellerkmann RK, et al. Preoperative cerebral oxygena-
randomized controlled feasibility trial. Anesthesiology 2016; 124:826–836. && tion in high-risk noncardiac surgical patients: an observational study on
15. Kara I, Erkin A, Saclı H, et al. The effects of near-infrared spectroscopy on the postoperative mortality and complications. J Clin Monit Comput 2023;
neurocognitive functions in the patients undergoing coronary artery bypass 37:743–752.
grafting with asymptomatic carotid artery disease: a randomized prospective An observational prospective study investigated preoperative cerebral oxygenation
study. Ann Thorac Cardiovasc Surg 2015; 21:544–550. using NIRS in 130 high-risk noncardiac surgical patients, finding no significant
16. Lei L, Katznelson R, Fedorko L, et al. Cerebral oximetry and postoperative association between baseline rScO2 and 30-day mortality or major postoperative
delirium after cardiac surgery: a randomised, controlled trial. Anaesthesia complications.
2017; 72:1456–1466. 38. Wen S, Peng A, Boyle S, et al. A pilot study using preoperative cerebral tissue
17. Murniece S, Soehle M, Vanags I, Mamaja B. Near infrared spectroscopy oxygen saturation to stratify cardiovascular risk in major noncardiac surgery.
based clinical algorithm applicability during spinal neurosurgery and post- Anaesth Intensive Care 2017; 45:202–209.
operative cognitive disturbances. Medicina (Lithuania) 2019; 55:E179. 39. Laflam A, Joshi B, Brady K, et al. Shoulder surgery in the beach chair position
18. Rogers CA, Stoica S, Ellis L, et al. Randomized trial of near-infrared spectro- is associated with diminished cerebral autoregulation but no differences in
scopy for personalized optimization of cerebral tissue oxygenation during postoperative cognition or brain injury biomarker levels compared with supine
cardiac surgery. Br J Anaesth 2017; 119:384–393. positioning: the Anesthesia Patient Safety Foundation Beach Chair Study.
19. Green DW, Kunst G. Cerebral oximetry and its role in adult cardiac, non- Anesth Analg 2015; 120:176–185.
cardiac surgery and resuscitation from cardiac arrest. Anaesthesia 2017; 40. Dilmen OK, Akcil EF, Vehid H, Tunali Y. Cerebral oxygenation assessed by
72:48–57. & near-infrared spectroscopy in the sitting and prone positions during posterior
20. Chiong X, Wong Z, Lim S, et al. The use of cerebral oximetry in cardiac fossa surgery: a prospective, randomized clinical study. Braz J Anesthesiol
&& surgery: a systematic review and meta-analysis of randomized controlled 2023; 73:589–594.
trials. Ann Card Anaesth 2022; 25:384–398. This prospective, randomized clinical study on posterior fossa surgery compared
A review and meta-analysis of 14 RCTs examined the impact of cerebral oximetry sitting position and prone position, revealing gradual reductions in rSO2 following
on postoperative cognitive dysfunction in cardiac surgery. The findings suggest patient positioning.
potential benefits of cerebral oximetry in reducing cognitive dysfunction postsur- 41. Schramm P, Tzanova I, Hagen F, et al. Cerebral oxygen saturation and cardiac
gery (lower incidence of postoperative cognitive dysfunction). output during anaesthesia in sitting position for neurosurgical procedures: a
21. Harilall Y, Adam JK, Biccard BM, Reddi A. The effect of optimising cerebral prospective observational study. Br J Anaesth 2016; 117:482–488.
tissue oxygen saturation on markers of neurological injury during coronary 42. Khan JM, McInnis CL, Ross-White A, et al. Overview and diagnostic accuracy
artery bypass graft surgery. Heart Lung Circ 2014; 23:68–74. of near infrared spectroscopy in carotid endarterectomy: a systematic review
22. Robba C, Battaglini D, Rasulo F, et al. The importance of monitoring cerebral and meta-analysis. Eur J Vasc Endovasc Surg 2021; 62:695–704.
& oxygenation in non brain injured patients. J Clin Monit Comput 2023; 43. Kondov S, Beyersdorf F, Sch€ ollhorn J, et al. Outcome of near-infrared
37:943–949. spectroscopy-guided selective shunting during carotid endarterectomy in
A detailed open-access review on the role of noninvasive cerebral oxygenation general anesthesia. Ann Vasc Surg 2019; 61:170–177.
monitoring in nonbrain-injured patients to prevent cerebral hypoxemia and improve 44. Hemmerling TM, Bluteau MC, Kazan R, Bracco D. Significant decrease of
outcomes in various clinical settings. cerebral oxygen saturation during single-lung ventilation measured using
23. Massari D, De Keijzer IN, Scheeren TWL. Cerebral monitoring in surgical ICU absolute oximetry. Br J Anaesth 2008; 101:870–875.
patients. Curr Opin Crit Care 2021; 27:701–708. 45. Kazan R, Bracco D, Hemmerling TM. Reduced cerebral oxygen saturation
24. Cropsey C, Kennedy J, Han J, Pandharipande P. Cognitive dysfunction, measured by absolute cerebral oximetry during thoracic surgery correlates
delirium, and stroke in cardiac surgery patients. Semin Cardiothorac Vasc with postoperative complications. Br J Anaesth 2009; 103:811–816.
Anesth 2015; 19:309–317. 46. Tang L, Kazan R, Taddei R, et al. Reduced cerebral oxygen saturation during
25. Moore CC, Yu S, Aljure O. A comprehensive review of cerebral oximetry in thoracic surgery predicts early postoperative cognitive dysfunction. Br J
& cardiac surgery. J Card Surg 2022; 37:5418–5433. Anaesth 2012; 108:623–629.
A comprehensive review on the role of brain cerebral oximetry in the perioperative 47. Casati A, Fanelli G, Pietropaoli P, et al. Monitoring cerebral oxygen saturation
environment in cardiac surgery, with special emphasis on neurocognitive out- in elderly patients undergoing general abdominal surgery: a prospective
comes, morbidity, or mortality. cohort study. Eur J Anaesthesiol 2007; 24:59–65.
26. Uysal S, Lin HM, Trinh M, et al. Optimizing cerebral oxygenation in cardiac 48. Casati A, Fanelli G, Pietropaoli P, et al., Collaborative Italian Study Group
surgery: a randomized controlled trial examining neurocognitive and on Anesthesia in Elderly Patients. Continuous monitoring of cerebral
perioperative outcomes. J Thorac Cardiovasc Surg 2020; 159:943. oxygen saturation in elderly patients undergoing major abdominal surgery
e3–953.e3. minimizes brain exposure to potential hypoxia. Anesth Analg 2005;
27. Semrau JS, Motamed M, Ross-White A, Boyd JG. Cerebral oximetry and 101:740–747.
preventing neurological complication postcardiac surgery: a systematic re- 49. Li H, Fu Q, Wu Z, et al. Cerebral oxygen desaturation occurs frequently in
view. Eur J Cardio-Thorac Surg 2021; 59:1144–1154. patients with hypertension undergoing major abdominal surgery. J Clin Monit
28. Murkin JM. Cerebral oximetry: monitoring the brain as the index organ. Comput 2018; 32:285–293.
Anesthesiology 2011; 114:12–13. 50. Papadopoulos G, Karanikolas M, Liarmakopoulou A, et al. Cerebral oximetry
29. Flechet M, G€ uiza F, Scharlaeken I, et al. Near-infrared-based cerebral oximetry and cognitive dysfunction in elderly patients undergoing surgery for hip
for prediction of severe acute kidney injury in critically ill children after cardiac fractures: a prospective observational study. Open Orthop J 2012;
surgery. Crit Care Explor 2019; 1:e0063. 6:400–405.
30. Serraino GF, Murphy GJ. Effects of cerebral near-infrared spectroscopy on 51. Berger M, Mark JB, Kreuzer M. Of parachutes, speedometers, and EEG: what
the outcome of patients undergoing cardiac surgery: a systematic review of evidence do we need to use devices and monitors? Anesth Analg 2020;
randomised trials. BMJ Open 2017; 7:e016613. 130:1274–1277.
31. Ko SH, Song JW, Shim JK, et al. Low intraoperative cerebral oxygen saturation 52. Calderone A, Jarry S, Couture EJ, et al. Early detection and correction of
& is associated with acute kidney injury after off-pump coronary artery bypass. & cerebral desaturation with noninvasive oxy-hemoglobin, deoxy-hemoglobin,
J Clin Med 2023; 12:359. and total hemoglobin in cardiac surgery: a case series. Anesth Analg 2022;
This study found that low intraoperative mean rScO2 independently predicts AKI 135:1304–1314.
following off-pump coronary artery bypass, suggesting it could serve as an early This case series explores early detection and correction of cerebral desatura-
indicator of renal injury. tion using noninvasive measures of oxy-haemoglobin, deoxy-haemoglobin, and
32. Delis A, Bautz D, Ehrentraut H, et al. Effects of different hemoglobin levels on total haemoglobin in cardiac surgery, highlighting distinct variations in hae-
&& near-infrared spectroscopy-derived cerebral oxygen saturation in elderly moglobin spectral absorption that correlate with different mechanisms of
patients undergoing noncardiac surgery. Transfus Med Hemother 2023; cerebral desaturation.
50:270–276. 53. Pearse RM, Harrison DA, MacDonald N, et al., OPTIMISE Study Group. Effect
This retrospective substudy found that NIRS-derived cerebral oxygen saturation of a perioperative, cardiac output-guided hemodynamic therapy algorithm on
correlates with perioperative haemoglobin levels, demonstrating potential impacts outcomes following major gastrointestinal surgery: a randomized clinical trial
of different transfusion strategies on cerebral oxygenation in elderly patients and systematic review. JAMA 2014; 311:2181–2190.
undergoing noncardiac surgery. 54. Gurgel ST, Do Nascimento P. Maintaining tissue perfusion in high-risk
33. Nielsen HB. Systematic review of near-infrared spectroscopy determined surgical patients: a systematic review of randomized clinical trials. Anesth
cerebral oxygenation during noncardiac surgery. Front Physiol 2014; 5:93. Analg 2011; 112:1384–1391.

6 www.co-criticalcare.com Volume 30  Number 00  Month 2024

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
CE: ; MCC/300618; Total nos of Pages: 7;
MCC 300618

Cerebral oximetry in high-risk surgical patients Navarro-Perez et al.

55. Hamilton MA, Cecconi M, Rhodes A. A systematic review and meta-analysis 57. Siggaard-Andersen O, Ulrich A, Gothgen IH. Classes of tissue hypoxia. Acta
on the use of preemptive hemodynamic intervention to improve postoperative Anaesthesiol Scand Suppl 1995; 107:137–142.
outcomes in moderate and high-risk surgical patients. Anesth Analg 2011; 58. Godoy DA, Murillo-Cabezas F, Suarez JI, et al. THE MANTLE’ bundle for
112:1392–1402. minimizing cerebral hypoxia in severe traumatic brain injury. Crit Care 2023; 27:13.
56. Denault A, Deschamps A, Murkin JM. A proposed algorithm for the intrao- 59. Zorrilla-Vaca A, Healy R, Grant MC, et al. Intraoperative cerebral oximetry-
perative use of cerebral near-infrared spectroscopy. Semin Cardiothorac based management for optimizing perioperative outcomes: a meta-analysis of
Vasc Anesth 2007; 11:274–281. randomized controlled trials. Can J Anaesth 2018; 65:529–542.

1070-5295 Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved. www.co-criticalcare.com 7

Copyright © 2024 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.