Cerebral Near-infrared Spectroscopy Research Articles

Association between pediatric postoperative delirium and regional cerebral oxygen saturation: a prospective observational study

BackgroundPostoperative delirium (POD) represents a prevalent and noteworthy complication in the context of pediatric surgical interventions. In recent times, a hypothesis has emerged positing that cerebral ischemia and regional cerebral oxygen desaturation might serve as potential catalysts in the pathogenesis of POD. The primary aim of this study was to methodically examine the potential relationship between POD and regional cerebral oxygen saturation (rSO2) and to assess the predictive and evaluative utility of rSO2 in the context of POD.MethodsThis prospective observational study was conducted at the Children’s Hospital, Zhejiang University School of Medicine, Zhejiang, China, spanning the period from November 2020 to March 2021. The research cohort comprised children undergoing surgical procedures within this clinical setting. To measure rSO2 dynamics, cerebral near-infrared spectroscopy (NIRS) was used to monitor rSO2 levels both before and after surgery. In addition, POD was assessed in the paediatric patients according to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5) criteria. The analysis of the association between the rSO2 index and the incidence of POD was carried out through the application of either the independent samples t-test or the nonparametric rank-sum test. To ascertain the threshold value of the adjusted rSO2 index for predictive and evaluative purposes regarding POD in the pediatric population, the Receiver Operating Characteristics (ROC) curve was employed.ResultsA total of 211 cases were included in this study, of which 61 (28.9%) developed POD. Participants suffering delirium had lower preoperative rSO2mean, lower preoperative rSO2min, and lower postoperative rSO2min, higher ∆rSO2mean, higher amount of ∆rSO2mean, lower ∆rSO2min (P < 0.05). Preoperative rSO2mean (AUC = 0.716, 95%CI 0.642–0.790), ∆rSO2mean (AUC = 0.694, 95%CI 0.614–0.774), amount of ∆rSO2mean (AUC = 0.649, 95%CI 0.564–0.734), preoperative rSO2min (AUC = 0.702, 96%CI 0.628–0.777), postoperative rSO2min (AUC = 0.717, 95%CI 0.647–0.787), and ∆rSO2min (AUC = 0.714, 95%CI 0.638–0.790) performed well in sensitivity and specificity, and the best threshold were 62.05%, 1.27%, 2.41%, 55.68%, 57.36%, 1.29%.ConclusionsThere is a close relationship between pediatric POD and rSO2. rSO2 could be used as an effective predictor of pediatric POD. It might be helpful to measure rSO2 with NIRS for early recognizing POD and making it possible for early intervention.

Comparison the Cerebroprotective Effect of Sevoflurane and Propofol in Patients with Carotid Artery Stenosis Undergoing Coronary Artery Bypass Grafting: A Randomized Clinical Study

Objective: The Objective of the study was to evaluate the perioperative cerebral protective effect of sevoflurane and propofol in patients with carotid artery stenosis undergoing coronary artery bypass grafting. Materials and Methods: A randomized clinical study included 200 patients with preoperative carotid artery stenosis &amp;lt;50% scheduled for cardiac surgery with cardiopulmonary bypass. The patients were classified into 2 groups (each=100), Sevoflurane group: The patients received sevoflurane (concentration 1% to 4%) as an inhalational agent. Propofol group: The patients received propofol infusion (4-6 mg/kg/hr). The sevoflurane and propofol were given during the whole procedure (before, during, and after cardiopulmonary bypass). The monitors included heart rate, mean arterial blood pressure (MAP), central venous pressure and cerebral near-infrared spectroscopy (NIRS), the incidence of postoperative cognitive dysfunction and stroke. Results: There was no significant difference in the perioperative heart rate, mean arterial blood pressure, central venous pressure, and the right or left regional cerebral oxygen saturation between the two groups (P&amp;gt;0.05). The incidence of postoperative neurological complication was significantly lower with sevoflurane than propofol (P=0.012). The incidence of delirium was significantly lower with sevoflurane than propofol (P=0.023). The incidence of stroke was lower with sevoflurane than propofol, but the difference was insignificant (P=0.682). The ICU and hospital length of stay were shorter with sevoflurane than propofol (P=0.013, P=0.033 respectively). Conclusions: The sevoflurane was associated with a lower incidence of postoperative cognitive dysfunction than propofol in patients with carotid artery stenosis undergoing coronary artery bypass grafting.

Expanding safety boundaries in pediatric robotic-assisted laparoscopic surgery: are we protecting our children?

Little is known about the effects of CO2 insufflation (CDI) on cerebral oxygen saturation (CrSO2) during laparoscopy in the pediatric population. In children undergoing robotic-assisted laparoscopic pyeloplasty (RALP), we prospectively assessed the effects of CDI using standard monitoring and cerebral near-infrared spectroscopy (NIRS). We also explored whether a correlation existed between CrSO2 and parameters known to affect cerebral blood flow. Between January 2021 and September 2023, a cohort of consecutive children older than 2years underwent RALP at Necker-Enfants Malades Hospital in Paris. A ventilation protocol aimed to prevent hypercarbia was implemented. Data collected included standard monitoring parameters and CrSO2 by NIRS. Thirty patients (16 females), mean age 5.5 ± 3.9 (2.0-9.5) years, were included. Twenty-three patients underwent a retroperitoneal approach. The mean baseline CrSO2 value was 83.0 ± 9.8. Mean CrSO2 decreased during progressive CDI, never below baseline values, while standard-monitoring parameters did not significantly change. No significant correlation was detected between CrSO2 and end tidal CO2, or between CrSO2 and mean arterial pressure, at any operative time. During RALP, a gradual CDI doesn't cause pathological derangements of CrSO2. The lack of correlation between CrSO2 and standard parameters affecting cerebral blood flow suggests the likely presence of cerebral autoregulation in our population.

Cerebral oxygen metabolism and brain electrical activity of healthy full-term neonates in high-altitude areas: a multicenter clinical research protocol

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates. Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity. This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes. The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes, and corresponding reference ranges will be established. The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance, with altitude gradients divided into 4 categories: 800 m, 1 900 m, 2 400 m, and 3 500 m, with an anticipated sample size of 170 neonates per altitude gradient. This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.

Influence of umbilical cord clamping time on cerebral oxygenation and early cardiac function in term infants.

Delayed cord clamping is the standard of care for both term and preterm infants worldwide. The aim of this study was to evaluate the effect of 60-second or 180-second delayed cord clamping during labor on cerebral oxygenation and cardiac function. Healthy newborns were divided into two groups: a 60-second delay in cord clamping (60-s DCC) and a 180-second delay in cord clamping (180-s DCC) at birth. Pulse oximetry and cerebral near-infrared spectroscopy (cNIRS) probes were placed during postnatal care. A total of 84 healthy newborns were included in this study. Preductal oxygen saturation (SpO2), heart rate, and cNIRS values were recorded at 5 and 10 minutes after delivery. The cardiac function of the infants was assessed by echocardiography at 3-7 days postnatally. There was no significant difference between the groups in SpO2 and cNIRS values at 5 and 10 min. While there was no significant difference in the number of neonates with targeted SpO2 at the 5th and 10th min and targeted cNIRS values at the 10th min, there was a significant difference in the number of neonates with target cNIRS values at the 5th min between groups (p < 0.001). Echocardiographic findings showed that pulmonary flow velocity was increased in the 180-s DCC group; the difference was statistically significant (p = 0.04). Our results showed that the number of infants with normal cNIRS values regarding cerebral oxygenation was higher in the 180-s DCC group. The pulmonary flow velocity was significantly increased in the 180-s DCC group in terms of echocardiographic findings.

Presurgical Use of Hypoxic Mixture for Systemic Perfusion Improvement in Neonates With Complex Congenital Heart Disease: A Systematic Review and Meta-Analysis.

Oxygen therapy is essential for the survival of preterm babies and critically ill newborns; however, it has the potential to cause harm through hypoxemia or hyperoxemia. Newborns with complex congenital heart diseases (CHD) suffer from oxygen fluctuations due to the disease and its treatments, altering pre and postnatal development. The objective of this study is to evaluate the evidence for using a hypoxic mixture to decrease pulmonary over-circulation and improve systemic perfusion before surgical interventions in newborns with complex CHD that course with pulmonary over-circulation and systemic hypoperfusion. A search was conducted in PubMed, EMBASE, LILACS, Scielo, Taylor and Francis, SAGE, and Science Direct databases from 2000 to 2022 by two independent authors, including articles with hypoxic mixture treatment in observational studies or trials, with pre-treatment and post-treatment measurements in the same patient, or two groups or more comparisons. Six articles were selected, with a total of 75 patients. The primary outcome was improved systemic circulation and decreased pulmonary over-circulation measured directly with Qp/Qs and indirectly with oxygen saturation and cerebral near-infrared spectroscopy (NIRS). In addition, we performed a meta-analysis for oxygen saturation and cerebral NIRS. Oxygen saturation was the value uniformly reported; three studies reported a significantly lower oxygen saturation after the hypoxic mixture. The cerebral NIRS was measured in 4 studies, with inconsistent results. After using the hypoxic mixture, the Qp/Qs calculation was lower in the two studies but was not statistically significant. The meta-analysis for oxygen saturation showed a fixed effect post-hypoxic therapy of -0.7 (-1.06; -0.35), p < 0.001. The meta-analysis of two studies that measured cerebral NIRS did not show a statistically significant difference at 12 and 24 hours. In conclusion, this is the first systematic review and meta-analysis regarding the pre-operative use of hypoxic gas mixtures for newborns with complex congenital heart disease. Treatment results in lower oxygen saturations, but there is a lack of evidence of improvement in systemic perfusion. The utilization of this therapy is controversial, and better evidence is necessary.

IMPACT OF HIGH-DOSE VASOPRESSOR DURING ENDOTOXIC SHOCK ON THE CEREBRAL, LINGUAL, HEPATIC, AND RENAL MICROCIRCULATION EVALUATED BY NEAR-INFRARED SPECTROSCOPY IN SWINE.

Background: High-dose vasopressors maintain blood pressure during septic shock but may adversely reduce microcirculation in vital organs. We assessed the effect of high-dose norepinephrine and vasopressin on the microcirculation of the brain, tongue, liver, and kidney during endotoxic shock using near-infrared spectroscopy (NIRS). Methods: Thirteen pigs (24.5 ± 1.8 kg) were anesthetized, and an NIRS probe was attached directly to each organ. Approximately 0.2, 0.5, 1, and 2 μg/kg/min of norepinephrine were administered in a stepwise manner, followed by 0.5, 1, 2, and 5 μg/kg/min of sodium nitroprusside in normal condition. Moreover, 1 μg/kg/h of lipopolysaccharide was administered continuously after 100 μg bolus to create endotoxic shock and after 1,000 mL of crystalloid infusion and high-dose norepinephrine (2, 5, 10, and 20 μg/kg/min) and vasopressin (0.6, 1.5, 3, and 6 U/min) were administered in a stepwise manner. The relationship between the MAP and each tissue oxygenation index (TOI) during vasopressor infusion was evaluated. Results: Three pigs died after receiving lipopolysaccharides, and 10 were analyzed. An increase of >20% from the baseline MAP induced by high-dose norepinephrine during endotoxic shock reduced the TOI in all organs except the liver. The elevation of MAP to baseline with vasopressin alone increased the kidney and liver TOIs and decreased the tongue TOI. Conclusion: Forced blood pressure elevation with high-dose norepinephrine during endotoxic shock decreased the microcirculation of vital organs, especially the kidney. Cerebral TOI may be useful for identifying the upper limit of blood pressure, at which norepinephrine impairs microcirculation.

Differences in Cerebral Tissue Oxygenation in Preterm Neonates Receiving Adult or Cord Blood Red Blood Cell Transfusions

Repeated transfusions in preterm neonates with anemia of prematurity replace fetal hemoglobin (HbF) with adult Hb (HbA), which has a low oxygen affinity. The reduction of HbF is associated with a higher incidence of retinopathy of prematurity (ROP). To assess whether HbF and HbA are differently associated with cerebral tissue oxygenation in preterm neonates. This cohort study was a single-center, pilot study on cerebral oxygenation kinetics in preterm neonates with a gestational age between 24.0 weeks and 27.9 weeks who were admitted to the neonatal intensive care unit of Policlinico Universitario A. Gemelli IRCCS from December 27, 2021, to May 15, 2023. This study was ancillary to the ongoing, double-blind, multicenter Umbilical or Adult Donor Red Blood Cells in Extremely Low Gestational Age Neonates and Retinopathy of Prematurity (BORN) randomized clinical trial. The BORN trial outcome was ROP severity in neonates randomized to receive standard packed red blood cell (PRBC) transfusions obtained from RBCs of adult donors (A-RBCs) or from cord blood (CB-RBCs). According to standard procedures at the institute's neonatal intensive care unit, patients concurrently received continuous cerebral near-infrared spectroscopy (NIRS) monitoring. This cohort study was not prespecified in the trial protocol. Transfusion with A-RBCs or CB-RBCs. The main outcome was the kinetics of cerebral regional oxygen saturation (crSO2) and cerebral fraction of tissue oxygen extraction (cFTOE) associated with A-RBC or CB-RBC transfusions. Cerebral NIRS monitoring was performed by neonatologists and nurses, who were blinded to the PRBC type. The NIRS monitoring was conducted starting with the blood product order, during transfusion, and for the subsequent 24 hours after transfusion completion. The mean treatment effects of A-RBCs or CB-RBCs were quantified using a linear mixed model for repeated measures. Of 23 randomized neonates, 17 (11 male [64.7%]; median gestational age at birth, 25.6 weeks [IQR, 25.3-26.1 weeks]) with a median birth weight of 840 g (IQR, 580-900 g) were included in the study; NIRS was evaluated for 42 transfusion episodes, of which 22 were A-RBCs and 20 were CB-RBCs. Globally considering all posttransfusion time points, the overall crSO2 covariate-adjusted mean after CB-RBC transfusions was 5.27% lower (95% CI, 1.20%-9.34%; P = .01) than that after A-RBC transfusions, while the cFTOE after CB-RBC transfusions was 6.18% higher (95% CI, 1.66%-10.69%; P = .009) than that after A-RBCs. The findings of this cohort study suggest that A-RBC transfusions may be associated with more oxygen delivery to cerebral tissues of preterm neonates than transfusions from CB-RBCs. This finding may explain the previously observed association between low HbF and high ROP risk. It also suggests that use of CB to meet the RBC transfusion needs of neonates with a gestational age of less than 28 weeks may protect cerebral tissues from overexposure to oxygen.

Time course of cerebral oxygenation and cerebrovascular reactivity in Kyrgyz highlanders. A five-year prospective cohort study.

Introduction: This prospective cohort study assessed the effects of chronic hypoxaemia due to high-altitude residency on the cerebral tissue oxygenation (CTO) and cerebrovascular reactivity. Methods: Highlanders, born, raised, and currently living above 2,500m, without cardiopulmonary disease, participated in a prospective cohort study from 2012 until 2017. The measurements were performed at 3,250m. After 20min of rest in supine position while breathing ambient air (FiO2 0.21) or oxygen (FiO2 1.0) in random order, guided hyperventilation followed under the corresponding gas mixture. Finger pulse oximetry (SpO2) and cerebral near-infrared spectroscopy assessing CTO and change in cerebral haemoglobin concentration (cHb), a surrogate of cerebral blood volume changes and cerebrovascular reactivity, were applied. Arterial blood gases were obtained during ambient air breathing. Results: Fifty three highlanders, aged 50 ± 2years, participated in 2017 and 2012. While breathing air in 2017 vs. 2012, PaO2 was reduced, mean ± SE, 7.40 ± 0.13 vs. 7.84 ± 0.13kPa; heart rate was increased 77 ± 1 vs. 70 ± 1bpm (p < 0.05) but CTO remained unchanged, 67.2% ± 0.7% vs. 67.4% ± 0.7%. With oxygen, SpO2 and CTO increased similarly in 2017 and 2012, by a mean (95% CI) of 8.3% (7.5-9.1) vs. 8.5% (7.7-9.3) in SpO2, and 5.5% (4.1-7.0) vs. 4.5% (3.0-6.0) in CTO, respectively. Hyperventilation resulted in less reduction of cHb in 2017 vs. 2012, mean difference (95% CI) in change with air 2.0 U/L (0.3-3.6); with oxygen, 2.1 U/L (0.5-3.7). Conclusion: Within 5years, CTO in highlanders was preserved despite a decreased PaO2. As this was associated with a reduced response of cerebral blood volume to hypocapnia, adaptation of cerebrovascular reactivity might have occurred.

The Inadequate Oxygen Delivery Index and Its Correlation with Venous Saturation in the Pediatric Cardiac Intensive Care Unit.

Continuous monitoring software, T3, has an integrated index called the inadequate oxygen delivery index 50% (IDO2-50) which displays a probability that the mixed venous saturation is below a user-selected threshold of 30-50%. The primary aim of this study was to determine the correlation of the IDO2-50 with a measured venous saturation. The secondary aim of this study was to characterize the hemodynamic factors that contributed to the IDO2-50. This single-center, retrospective study aimed to characterize the correlation between IDO2-50 and inferior vena cava (IVC) saturation. A Bayesian Pearson correlation was conducted to assess the correlation between the collected variables of interest, with a particular interest in the correlation between the IDO2-50 and the IVC saturation. Receiver operator curve (ROC) analysis to assess the ability of the IDO2-50 to identify when the venous saturation was less than 50%. Bayesian linear regression was done with the IDO2-50 (dependent variable) and other independent variables. A total of 113 datasets were collected across 15 unique patients. IDO2-50 had moderate correlation with the IVC saturation (correlation coefficient -0.569). The IDO2-50 had a weak but significant correlation with cerebral near-infrared spectroscopy (NIRS) values, a weak but significant correlation with heart rate, and a moderate and significant correlation with arterial saturation. ROC analysis demonstrated that the IDO2-50 had a good ability to identify a venous saturation below 50%, with an area under the curve of 0.797, cutoff point of 24.5 with a sensitivity of 81%, specificity of 66%, positive predictive value of 44%, and negative predictive value of 91%. Bayesian linear regression analysis yielded the following model: 237.82 + (1.18 × age in months)-(3.31 × arterial saturation)-(1.92 × cerebral NIRS) + (0.84 × heart rate). The IDO2 index has moderate correlation with IVC saturation. It has good sensitive and negative predictive value. Cerebral NIRS does appear to correlate better with the underlying venous saturation than the IDO2 index.

Correlation between cerebral hemodynamic functional near-infrared spectroscopy and positron emission tomography for assessing mild cognitive impairment and Alzheimer's disease: An exploratory study.

This study was performed to investigate the usefulness of functional near-infrared spectroscopy (fNIRS) by conducting a comparative analysis of hemodynamic activation detected by fNIRS and positron emission tomography (PET) and magnetic resonance imaging (MRI) in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Participants were divided into four groups: the subjective memory impairment (SMI), amnestic MCI (aMCI), non-amnestic MCI (naMCI), and AD groups. We recorded the hemodynamic response during the semantic verbal fluency task (SVFT) using a commercial wireless continuous-wave NIRS system. The correlation between the parameters of the neuroimaging assessments among the groups was analyzed. Region of interest-based comparisons showed that the four groups had significantly different hemodynamic responses during SVFT in the bilateral dorsolateral prefrontal cortex (DLPFC). The linear mixed effect model result indicates that the mean ΔHbO2 from the bilateral DLPFC regions showed a significant positive correlation to the overall FDG-PET after controlling for age and group differences in the fNIRS signals. Amyloid PET signals tended to better differentiate the AD group from other groups, and fNIRS signals tended to better differentiate the SMI group from other groups. In addition, a comparison between the group pairs revealed a mirrored pattern between the hippocampal volume and hemodynamic response in the DLPFC. The hemodynamic response detected by fNIRS showed a significant correlation with metabolic and anatomical changes associated with disease progression. Therefore, fNIRS may be considered as a screening tool to predict the hemodynamic and metabolic statuses of the brain in patients with MCI and AD.

Trends on Near-Infrared Spectroscopy Associated With Acute Brain Injury in Venoarterial Extracorporeal Membrane Oxygenation.

We aimed to determine the association between cerebral regional oxygen saturation (rSO 2 ) trends from cerebral near-infrared spectroscopy (cNIRS) and acute brain injury (ABI) in adult venoarterial extracorporeal membrane oxygenation (VA-ECMO) patients. ABI was defined as intracranial hemorrhage, ischemic stroke, hypoxic ischemic brain injury, or brain death during ECMO. rSO 2 values were collected from left and right cerebral oximetry sensors every hour from ECMO cannulation. Cerebral desaturation was defined as consecutive hours of rSO 2 < 40%. rSO 2 asymmetry was determined by (a) averaging left/right rSO 2 difference over the entire ECMO run; (b) consecutive hours of rSO 2 asymmetry. Sixty-nine VA-ECMO patients (mean age 56 years, 65% male) underwent cNIRS. Eighteen (26%) experienced ABI. When the mean rSO 2 asymmetry was >8% there was significantly increased odds of ABI (aOR = 39.4; 95% CI = 4.1-381.4). Concurrent rSO 2 < 40% and rSO 2 asymmetry >10% for >10 consecutive hours (asymmetric desaturation) was also significantly associated with ABI (aOR = 5.2; 95% CI = 1.2-22.2), but neither criterion alone were. Mean rSO 2 asymmetry>8% exhibited 39% sensitivity and 98% specificity for detecting ABI, with an area under the curve (AUC) of 0.86, and asymmetric desaturation had 33% sensitivity and 88% specificity, with an AUC of 0.72. These trends on NIRS monitoring may help detect ABI in VA-ECMO patients.

Preterm Infants off Positive Pressure Respiratory Support Have a Higher Incidence of Occult Cerebral Hypoxia

To use cerebral near-infrared spectroscopy (NIRS) to quantify occult cerebral hypoxia across respiratory support modes in preterm infants. In this prospective, longitudinal, observational study, infants ≤32weeks gestation underwent serial pulse oximetry (oxygen saturation [SpO2]) and cerebral NIRS monitoring (4-6hours per session) following a standardized recording schedule (daily for 2 weeks, every other day for 2 weeks, then weekly until 35weeks corrected gestational age). Four calculations were made: median cerebral saturation, median cerebral hypoxia burden (proportion of NIRS samples below the hypoxia threshold [<67%]), median systemic saturation, and median systemic hypoxia burden (proportion of SpO2 samples below the desaturation threshold [<85%]). During each recording session, respiratory support mode was noted (room air, low-flow nasal cannula, high-flow nasal cannula, noninvasive positive pressure ventilation, continuous positive airway pressure, and invasive ventilation). There were 1013 recording sessions made from 174 infants with a median length of 6.9hours. Although the systemic (SpO2) hypoxia burden was significantly greater for infants on the highest respiratory support (invasive and noninvasive positive pressure ventilation), the cerebral hypoxia burden was significantly greater during recording sessions made on the lowest respiratory support (8% for room air; 29% for low-flow nasal cannula). Premature infants on the highest levels of respiratory support have less cerebral hypoxia than those on lower respiratory support. These results raise concern about unrecognized cerebral hypoxia during lower acuity periods of neonatal intensive care unit hospitalization and adverse outcomes.

Heterogeneity in Clinical Practices for Post-Cardiotomy Extracorporeal Life Support: a Pilot Survey from the PELS-1 Multicenter Study.

High-quality evidence for post-cardiotomy extracorporeal life support (PC-ECLS) management is lacking. This study investigated the real-world PC-ECLS clinical practices. This cross-sectional, multi-institutional, international pilot survey explored center organization, anticoagulation management, left ventricular unloading, distal limb perfusion, PC-ECLS monitoring and transfusions practices. Twenty-nine questions were distributed among 34 hospitals participating in the Post-cardiotomy Extra-Corporeal Life Support Study. Of the 32 centers [16 low-volume (50%); 16 high-volume (50%)] that responded, 16 (50%) had dedicated ECLS specialists. Twenty-six centers (81.3%) reported using additional mechanical circulatory supports. Anticoagulation practices were highly heterogeneous: 24 hospitals (75%) reported using patient's bleeding status as a guide, without a specific threshold in 54.2% of cases. Transfusion targets ranged 7-10 g/dL. Most centers used cardiac venting on a case-by-case basis (78.1%) and regular distal limb perfusion (84.4%). Nineteen (54.9%) centers reported dedicated monitoring protocols including daily echocardiography (87.5%), Swan-Ganz catheterization (40.6%), cerebral near-infrared spectroscopy (53.1%) and multimodal assessment of limb ischemia. Inspection of the circuit (71.9%), oxygenator pressure drop (68.8%), plasma free hemoglobin (75%), d-dimer (59.4%), lactate dehydrogenase (56.3%) and fibrinogen (46.9%) are used to diagnose hemolysis and thrombosis. This study shows remarkable heterogeneity in clinical practices for PC-ECLS management. More standardized protocols and better implementation of available evidence are recommended.

EEG response to a high volume (1.5 mL/kg) caudal block in infants less than 3 months

IntroductionThe substantial compression of the dural sac and the subsequent cranial shift of cerebrospinal fluid caused by a high-volume caudal block has been shown to significantly but transiently reduce cerebral...

Cerebral near-infrared spectroscopy monitoring to predict periventricular-intraventricular haemorrhage and neurodevelopmental outcomes in preterm infants: a protocol for a systematic review and meta-analysis

IntroductionPeriventricular-intraventricular haemorrhage (PV-IVH) is one of the major cause of mortality and long-term neurodevelopmental sequela in preterm infants born at less than 32 weeks of gestation. Near-infrared spectroscopy (NIRS) monitoring...

Preterm infants variability in cerebral near-infrared spectroscopy measurements in the first 72-h after birth.

Cerebral near-infrared spectroscopy is a non-invasive tool used to measure regional cerebral tissue oxygenation (rScO2) initially validated in adult and pediatric populations. Preterm neonates, vulnerable to neurologic injury, are attractive candidates for NIRS monitoring; however, normative data and the brain regions measured by the current technology have not yet been established for this population. This study's aim was to analyze continuous rScO2 readings within the first 6-72 h after birth in 60 neonates without intracerebral hemorrhage born at ≤1250 g and/or ≤30 weeks' gestational age (GA) to better understand the role of head circumference (HC) and brain regions measured. Using a standardized brain MRI atlas, we determined that rScO2 in infants with smaller HCs likely measures the ventricular spaces. GA is linearly correlated, and HC is non-linearly correlated, with rScO2 readings. For HC, we infer that rScO2 is lower in infants with smaller HCs due to measuring the ventricular spaces, with values increasing in the smallest HCs as the deep cerebral structures are reached. Clinicians should be aware that in preterm infants with small HCs, rScO2 displayed may reflect readings from the ventricular spaces and deep cerebral tissue. Clinicians should be aware that in preterm infants with small head circumferences, cerebral near-infrared spectroscopy readings of rScO2 displayed may reflect readings from the ventricular spaces and deep cerebral tissue. This highlights the importance of rigorously re-validating technologies before extrapolating them to different populations. Standard rScO2 trajectories should only be established after determining whether the mathematical models used in NIRS equipment are appropriate in premature infants and the brain region(s) NIRS sensors captures in this population, including the influence of both gestational age and head circumference.

Editor's Choice Articles for March.

Welcome to March 2023 at Pediatric Critical Care Medicine (PCCM). There are three Editor’s Choices articles that each question established opinions and make us delve deeper into the relevant issues and potential implications for practice. The PCCM Connections for Readers focuses on biological mechanism–as a plea to our investigators and research authors, we do need to see more of this type of work at PCCM. WHAT ABOUT CORTICOSTEROIDS IN SEPSIS AND SEPTIC SHOCK? Klowak JA, Bijelic V, Barrowman N, et al; Genomics of Pediatric Septic Shock Investigators: The Association of Corticosteroids and Pediatric Sepsis Biomarker Risk Model (PERSEVERE)-II Biomarker Risk (1). Are we any closer to solving the question of using corticosteroid therapy in children presenting with septic shock? In this retrospective study of almost 500 children separated into two categories using the PERSEVERE-II biomarker score, the authors tested whether there was an interaction between grouping, corticosteroid use, and outcome. Our editorial sets this information in a historical context, from 2009 to 2021 (2), and makes us think about precision medicine, endotypes, and the contemporary randomized controlled trial (RCT). This new article and editorial follow a theme in PCCM discussed in the September 2022 issue (3), and readers should review the authors’ other relevant work about the difficulty of RCTs in the septic shock population (4,5). WHAT ABOUT THE COMPLEXITY OF FACTORS CONTRIBUTING TO OUTCOMES AFTER CARDIAC SURGERY? Brown KL, Moinuddin M, Jones A, et al: The Relationship Between Postoperative Complications and Children’s Quality of Life: A Mediation Analysis to Explore the Role of Family Factors (6). In this multicenter research from the United Kingdom, the authors identified a cardiac postoperative group with multiple morbidities and sought to identify a causal mediation analysis of parental health-related quality of life at 6 weeks after cardiac surgery, and their child’s quality of life at 6 months. Over 400 children contributed to the primary outcome and these new data add insight into the complexity of outcomes and the potential scope of psychological interventions to support parents of children who experience perioperative morbidities. Add this reading to the authors’ recent report on postoperative morbidities and neurodevelopment (7), and we are now building a more complete picture of how best to study late outcomes after critical illness (8,9). WHAT ABOUT THE MEASUREMENT OF CEREBRAL NEAR-INFRARED SPECTROSCOPY IN PEDIATRIC CARDIAC PATIENTS? Iliopoulis I, Cooper DS, Reagor JA, et al: Absolute Versus Relative Near-Infrared Spectroscopy in Pediatric Cardiac Patients (10). My third highlighted article is an analysis of near-infrared spectroscopy (NIRS) data: the devices and the validity of the measurements that we use during clinical care (10). Please read the report and even though it’s not what we thought or taught, our editorial writers argue that NIRS monitoring in patients with complex congenital heart disease is here to stay (11). Also, go back to a little-known Letter to the Editor in the January 2006 issue of PCCM with its powerful insights. In the letter, Britton Chance (1913–2010), the American founder of biomedical photonics and National Medal of Science winner in 1974, wrote to PCCM on the topic of quantification of brain oxygenation in humans in vivo (12). “PCCM CONNECTIONS” FOR READERS This month there are two other areas of research that pick up on our previous themes. They are of particular interest because they address mechanism, and we need to understand clinical biology if we are to make progress in our field. The first topic is the endothelial glycocalyx. We have previously published a definitive review about the endothelial glycocalyx as a fundamental determinant of vascular permeability in sepsis (13), and a clinical research observation of glycocalyx degradation products contributing to metabolic acidosis following cardiopulmonary bypass (14). In a single-center research study from Colombia, the authors (same ones that wrote the previous PCCM definitive review) look at the time course of glycocalyx degradation in children with sepsis following a bolus of intravenous fluids (15). The article comes with an editorial (16). The second topic is the morbidity of hyperoxia. In early 2022 we learned that there are 16 pediatric critical care studies with over 27 thousand patients that, collectively, suggests an association between hyperoxia and greater odds of mortality (17). We now have a mechanistic substudy nested within the pilot feasibility RCT of liberal versus conservative oxygenation targeting (i.e., pulse oximetry > 94% versus 88%−92%, respectively) (18). The authors report redox responses and gene expression of hypoxia-inducible factor 1a in the two oxygenation groups. Hopefully, their hypothesis will be tested in the now completed RCT of oxygen targeting and outcome in pediatrics (19). Finally, another highlight for me is a narrative essay entitled “The Trip of a Lifetime” (20).

New Development in Brain Monitoring for Cardiac Surgery.

Use of brain function monitoring is gaining interest to improve patient safety during cardiac surgery and in the intensive care unit. In this review, we highlight the clinical relevance of brain monitoring such as the cerebral near-infrared spectroscopy (NIRS), processed electroencephalography (pEEG), and transcranial Doppler (TCD). A clinical case will be presented to illustrate the potential of combining those technologies to optimize patient management during cardiac surgery. Even if brain monitoring alters management, interpretation in brain function requires knowledge about hemodynamic parameters and should be combined with other monitoring technology.

Abstract 11: Identifiable Patterns Of Noninvasive Cerebral Oximetry During Endovascular Therapy For Acute Ischemic Stroke Are Associated With Neurological Deterioration

Background: Cerebral near-infrared spectroscopy (NIRS) is a useful tool to monitor real-time cerebral oxygenation levels. However, the mechanisms through which varying oxygenation levels during endovascular thrombectomy (EVT) affect functional outcomes remain to be determined. In this study, we categorized NIRS trends into descriptive “fingerprints” and examined the relationship between these fingerprints and neurological worsening. Methods: We enrolled patients that presented to Yale New Haven Hospital with large vessel occlusion acute ischemic stroke and underwent EVT. NIRS was implemented into the standard operating procedure. Time stamps of defined events (medication administration, recanalization, etc.) were synchronized with corresponding NIRS values. We inspected NIRS curves from arrival to angio-suite to time of recanalization. Neurological deterioration was defined as an increase of 4 points or more on the National Institutes of Health Stroke Scale (NIHSS). Results: Forty-eight patients (mean age 72 ± 13, mean NIHSS 14) were analyzed. Five “fingerprints” were observed in the affected hemisphere: sustained decreases, downward rSO2 peaks, no change, upward rSO2 peaks, and sustained increases (Fig. 1), which were assigned nominal values of -2, -1, 0, 1, and 2, respectively. After adjusting for age and admission NIHSS, sustained decreases and downward rSO2 peaks were independently associated with neurological deterioration (P = 0.0076, Fig. 2). Conclusions: Identifiable NIRS “fingerprints” of downward rSO2 peaks and sustained decreases in the affected hemisphere during EVT are associated with neurological deterioration. Further distillation of identifiable intraprocedural NIRS trends in real time could provide guidance for anesthesia and hemodynamic management during EVT to optimize patient outcomes after stroke.