Cerebral Near-infrared Spectroscopy Monitoring Research Articles

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.

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.

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.

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...

Treating the body to prevent brain injury: lessons learned from the coronavirus disease 2019 pandemic.

We aim to provide the current evidence on utility and application of neuromonitoring tools including electroencephalography (EEG), transcranial Doppler (TCD), pupillometry, optic nerve sheath diameter (ONSD), cerebral near-infrared spectroscopy (cNIRS), somatosensory-evoked potentials (SSEPs), and invasive intracranial monitoring in COVID-19. We also provide recent evidence on management strategy of COVID-19-associated neurological complications. Despite the common occurrence of neurological complications, we found limited use of standard neurologic monitoring in patients with COVID-19. No specific EEG pattern was identified in COVID-19. Frontal epileptic discharge was proposed to be a potential marker of COVID-19 encephalopathy. TCD, ONSD, and pupillometry can provide real-time data on intracranial pressure. Additionally, TCD may be useful for detection of acute large vessel occlusions, abnormal cerebral hemodynamics, cerebral emboli, and evolving cerebral edema at bedside. cNIRS was under-utilized in COVID-19 population and there are ongoing studies to investigate whether cerebral oxygenation could be a more useful parameter than peripheral oxygen saturation to guide clinical titration of permissive hypoxemia. Limited data exists on SSEPs and invasive intracranial monitoring. Early recognition using standardized neuromonitoring and timely intervention is important to reduce morbidity and mortality. The management strategy for neurological complications is similar to those without COVID-19.

Study of the relationship between regional cerebral saturation and pCO2 changes during mechanical ventilation to evaluate modifications in cerebral perfusion in a newborn piglet model.

Near-infrared spectroscopy (NIRS) could be a useful continuous, non-invasive technique for monitoring the effect of partial pressure of carbon dioxide (PaCO2) fluctuations in the cerebral circulation during ventilation. The aim of this study was to examine the efficacy of NIRS to detect acute changes in cerebral blood flow following PaCO2 fluctuations after confirming the autoregulation physiology in piglets. Fourteen piglets (<72 h of life) were studied. Mean arterial blood pressure, oxygen saturation, pH, glycemia, hemoglobin, electrolytes, and temperature were monitored. Eight animals were used to evaluate brain autoregulation, assessing superior cava vein Doppler as a proxy of cerebral blood flow changing mean arterial blood pressure. Another 6 animals were used to assess hypercapnia generated by decreasing ventilatory settings and complementary CO2 through the ventilator circuit and hypocapnia due to increasing ventilatory settings. Cerebral blood flow was determined by jugular vein blood flow by Doppler and continuously monitored with NIRS. A decrease in PaCO2 was observed after hyperventilation (47.6±2.4 to 29.0±4.9 mmHg). An increase in PaCO2 was observed after hypoventilation (48.5±5.5 to 90.4±25.1 mmHg). A decrease in cerebral blood flow after hyperventilation (21.8±10.4 to 15.1±11.0 mL/min) and an increase after hypoventilation (23.4±8.4 to 38.3±10.5 mL/min) were detected by Doppler ultrasound. A significant correlation was found between cerebral oxygenation and Doppler-derived parameters of blood flow and PaCO2. Although cerebral NIRS monitoring is mainly used to detect changes in regional brain oxygenation, modifications in cerebral blood flow following experimental PaCO2 changes were detected in newborn piglets when no other important variables were modified.

Impact of Carbon Dioxide on Cerebral Oxygenation and Vital Parameters in Stable Preterm and Term Infants Immediately after Birth

Introduction: Carbon dioxide (pCO2) induces changes in the tone of cerebral vessels. The aim of the present study was to evaluate the impact of pCO2 on cerebral regional tissue oxygen saturation (crSO2), cerebral fractional tissue oxygen extraction (cFTOE), and cerebral tissue oxygen extraction (cTOE), measured with near-infrared spectroscopy (NIRS), in preterm and term infants 15 min after birth. Methods: Post hoc analyses of secondary outcome parameters of prospective observational studies were performed. Stable preterm and term infants with cerebral NIRS monitoring (INVOS 5100C) until minute 15 after birth and a blood gas analysis, performed between minutes 14–18 after birth, were included. Heart rate (HR) and arterial oxygen saturation (SpO2) were recorded. pCO2 was correlated with crSO2, cFTOE, cTOE, SpO2, HR, and partial pressure of oxygen (pO2). Results: Eleven preterm infants with a median (IQR) gestational age of 34.8 (32.7–36.1) weeks were analyzed. Mean ± SD pCO2 was 53.5 ± 4.2 mm Hg. At minute 15 after birth, crSO2 was 82.6 (74.3–91.3)%, cFTOE 0.15 ± 0.09, cTOE 14.6 ± 8.4%, SpO2 97.4 ± 2.1%, and HR 152 (136–167) bpm. pCO2 correlated negatively with crSO2 (p = 0.012) and positively with cFTOE (p = 0.035) and cTOE (p = 0.037). Eighty-four term infants with a gestational age of 39.0 (38.5–38.9) weeks were analyzed. pCO2 was 53.5 ± 6.3 mm Hg. At minute 15 after birth, crSO2 was 84.4 (80.8–85.1)%, cFTOE 0.14 ± 0.08, cTOE 13.6 ± 7.9%, SpO2 96.5 ± 2.6%, and HR 155 (153–163) bpm. pCO2 did only negatively correlate with pO2 (p = 0.034) in term infants. Conclusion: In preterm infants, higher pCO2 was associated with lower crSO2 and higher cFTOE/cTOE. In term infants, no associations were observed. The present findings suggest that the vasodilatative effect of pCO2 is less pronounced in preterm infants during immediate postnatal transition.

Clamped Carotid Dissection Can Reduce Postoperative Stroke After Carotid Endarterectomy.

Background: The outcomes of carotid endarterectomy (CEA) are constantly reported in a multitude of studies; however, the specific causes of perioperative stroke have been scarcely investigated. The aim of the present study was to analyze and categorize the causes of perioperative strokes after CEA. Methods: All CEAs performed from 2006 to 2019 in a single center were collected. CEA was routinely performed under general anesthesia, with routine shunting and patching, using cerebral near-infrared spectroscopy monitoring. Carotid exposure technique was classified as either clamped-dissection (CD) or preclamping-dissection (PCD) if the carotid bifurcation was dissected after or prior to carotid clamping. Perioperative and 30-day strokes and their possible mechanisms were evaluated according to preoperative symptoms and surgical technique adopted. Results: Among 1760 CEAs performed, 30 (1.7%) perioperative strokes occurred. 14 (47%) were identified upon emergence from general anesthesia, and 16 (53%) were noted in the first 30 days following intervention. Stroke etiology was categorized as follows: technical (acute thrombosis or intimal flap or due to intraoperative complications), embolic (no recognized technical defect), hemorrhagic, or contralateral. Symptomatic patients had a significantly higher rate of any type of stroke than asymptomatic patients (3.8% vs 0.9%, P = .0001). CD was protective for postoperative stroke (0.9% vs 3.1%, P = .001) in both symptomatic and asymptomatic patients (2.5% vs 5.9%, P = .05; 0.4% vs 1.9%, P = .005), particularly for the cohort in which symptomatic patients (0.7% vs 3.2%, P = .04) suffered postoperative embolic stroke. Conclusion: Perioperative stroke in CEA may be multifactorial in etiology, including a result of technical errors. A CD technique may help reduce the incidence of perioperative stroke.

The clinical effects of cerebral near-infrared spectroscopy monitoring (NIRS) versus no monitoring: a protocol for a systematic review with meta-analysis and trial sequential analysis

BackgroundMultiple clinical conditions are associated with cerebral hypoxia/ischaemia and thereby an increased risk of hypoxic-ischaemic brain injury. Cerebral near-infrared spectroscopy monitoring (NIRS) is a tool to monitor brain oxygenation and perfusion, and the clinical uptake of NIRS has expanded over recent years. Specifically, NIRS is used in the neonatal, paediatric, and adult perioperative and intensive care settings. However, the available literature suggests that clinical benefits and harms of cerebral NIRS monitoring are uncertain. As rates of clinically significant hypoxic-ischaemic brain injuries are typically low, it is difficult for randomised clinical trials to capture a sufficiently large number of events to evaluate the clinical effect of cerebral NIRS monitoring, when focusing on specific clinical settings. The aim of this systematic review will be to evaluate the benefits and harms of clinical care with access to cerebral NIRS monitoring versus clinical care without cerebral NIRS monitoring in children and adults across all clinical settings.MethodsWe will conduct a systematic review with meta-analysis and trial sequential analysis. We will only include randomised clinical trials. The primary outcomes are all-cause mortality, moderate or severe persistent cognitive or neurological deficit, and proportion of participants with one or more serious adverse events. We will search CENTRAL, EMBASE, MEDLINE, and the Science Citation Index Expanded from their inception and onwards. Two reviewers will independently screen all citations, full-text articles, and extract data. The risk of bias will be appraised using the Cochrane risk of bias tool version 2.0. If feasible, we will conduct both random-effects meta-analysis and fixed-effect meta-analysis of outcome data. Additional analysis will be conducted to explore the potential sources of heterogeneity (e.g. risk of bias, clinical setting).DiscussionAs we include trials across multiple clinical settings, there is an increased probability of reaching a sufficient information size. However, heterogeneity between the included trials may impair our ability to interpret results to specific clinical settings. In this situation, we may have to depend on subgroup analyses with inherent increased risks of type I and II errors.Systematic review registrationPROSPERO CRD42020202986. This systematic review protocol has been submitted for registration in the International Prospective Register of Systematic Reviews (PROSPERO) (http://www.crd.york.ac.uk/prospero) on the 12th of October 2020 and published on the 12th of November 2020 (registration ID CRD42020202986).

The Effects of Endotracheal Suctioning on Hemodynamic Parameters and Tissue Oxygenation in Pediatric Intensive Care Unit.

Airway secretions may increase in intubated patients due to the impaired mucociliary clearance, impaired cough reflex, abnormal glottic function, insufficient moisturizing, and respiratory tract infections. As with any intervention, patients should be cautiously monitored for possible complications during the endotracheal suctioning. Procedure-related changes in the cerebral and somatic tissue oxygenation, hemodynamics, and oxygen saturation can be observed in these patients. It is important to ensure maintenance of tissue oxygenation during these and other interventions performed in critically ill children. The aim of this study was to investigate the effects of the endotracheal suctioning on tissue oxygenation in patients undergoing mechanical ventilation in the pediatric intensive care unit. Cerebral and somatic near-infrared spectroscopy (NIRS) monitoring were performed noninvasively using standardized NIRS equipment as a means of monitoring regional tissue oxygenation. Vital signs, level of sedation, pain scores, and somatic and cerebral tissue oxygenation values of mechanically ventilated patients were recorded prospectively 5 minutes before, during, and after endotracheal suctioning. Cerebral NIRS measurements did not exhibit any statistically significant changes during endotracheal suctioning. Somatic NIRS levels changed significantly before, during, and after endotracheal suctioning and remained low throughout the procedure. Endotracheal suctioning is an invasive intervention that facilitates clearance of tracheal secretions and maintenance of the oxygenation and ventilation. The maintenance of the tissue oxygenation should be documented during these and other interventions performed on critically ill children. Somatic NIRS is a useful tool for monitoring tissue oxygenation during such procedures.

Pilot test of an online training module on near-infrared spectroscopy monitoring for the randomised clinical trial SafeBoosC-III

BackgroundSafeBoosC-III is an international randomised clinical trial to evaluate the effect of treatment of extremely preterm infants during the first 3 days of life based on cerebral near-infrared spectroscopy (NIRS) monitoring versus treatment and monitoring as usual. To ensure high quality of the trial intervention as well as of patient care, we have developed a multilingual web-based training program to train relevant staff and test their competence. As we enter an under-explored area of e-learning, we have conducted a pilot study on the first of the five modules comprising the web-based training program to test the feasibility of developing such a program for an international trial with limited resources.MethodsThe module in this study focuses on the principles and practice of NIRS monitoring. The pedagogical idea was to integrate training and certification. One-hundred doctors and nurses from five Neonatal Intensive Care Units across China, Spain and Denmark were invited to participate in the pilot study. Upon completion of the NIRS module, participants were invited to evaluate their experience by completing an online survey. Data from closed-ended questions were analysed using descriptive statistics while data from open-ended questions underwent thematic analysis.ResultsIn total, 81 of 100 invited staff members entered the training module and completed the online survey. The median time and the number of questions to pass the module was 15 minutes and seven questions, respectively. Most staff found the academic level of the learning material and quiz appropriate (85% and 93% of all staff members, respectively), as well as agreeing that the module was relevant to prepare them to ‘use the NIRS device’ (90%). Thematic analysis revealed issues such as a discrepancy between learning material and quiz questions, lack of clarity, and technical issues.ConclusionWe provide evidence of the feasibility of developing a multilingual web-based training program for an international trial, despite challenges such as low budget, language barriers and possibly differences in the clinical training of staff. Exploring the integration of training and certification for international trials, the positive results of this study motivate further developments.Trial registrationClinicalTrial.gov, NCT03770741. Registered 10 December 2018.

Cerebral near-infrared spectroscopy monitoring versus treatment as usual for extremely preterm infants: a protocol for the SafeBoosC randomised clinical phase III trial

BackgroundCerebral oxygenation monitoring may reduce the risk of death and neurologic complications in extremely preterm infants, but no such effects have yet been demonstrated in preterm infants in sufficiently powered randomised clinical trials. The objective of the SafeBoosC III trial is to investigate the benefits and harms of treatment based on near-infrared spectroscopy (NIRS) monitoring compared with treatment as usual for extremely preterm infants.Methods/designSafeBoosC III is an investigator-initiated, multinational, randomised, pragmatic phase III clinical trial. Inclusion criteria will be infants born below 28 weeks postmenstrual age and parental informed consent (unless the site is using ‘opt-out’ or deferred consent). Exclusion criteria will be no parental informed consent (or if ‘opt-out’ is used, lack of a record that clinical staff have explained the trial and the ‘opt-out’ consent process to parents and/or a record of the parents’ decision to opt-out in the infant’s clinical file); decision not to provide full life support; and no possibility to initiate cerebral NIRS oximetry within 6 h after birth. Participants will be randomised 1:1 into either the experimental or control group. Participants in the experimental group will be monitored during the first 72 h of life with a cerebral NIRS oximeter. Cerebral hypoxia will be treated according to an evidence-based treatment guideline. Participants in the control group will not undergo cerebral oxygenation monitoring and will receive treatment as usual. Each participant will be followed up at 36 weeks postmenstrual age. The primary outcome will be a composite of either death or severe brain injury detected on any of the serial cranial ultrasound scans that are routinely performed in these infants up to 36 weeks postmenstrual age. Severe brain injury will be assessed by a person blinded to group allocation. To detect a 22% relative risk difference between the experimental and control group, we intend to randomise a cohort of 1600 infants.DiscussionTreatment guided by cerebral NIRS oximetry has the potential to decrease the risk of death or survival with severe brain injury in preterm infants. There is an urgent need to assess the clinical effects of NIRS monitoring among preterm neonates.Trial registrationClinicalTrial.gov, NCT03770741. Registered 10 December 2018.

A practical approach to cerebral near-infrared spectroscopy (NIRS) directed hemodynamic management in noncardiac pediatric anesthesia.

Safeguarding cerebral function is of major importance during pediatric anesthesia. Premature, ex-premature, and full-term neonates can be vulnerable to physiological changes that occur during anesthesia and surgery. Data from studies performed during pediatric cardiac surgery and in neonatal/pediatric intensive care units have shown the benefits of near-infrared spectroscopy (NIRS) monitoring of regional cerebral oxygenation (c-rSO2 ). However, NIRS monitoring is seldom used during noncardiac pediatric anesthesia. Despite compelling evidence that blood pressure does not reflect end-organ perfusion, it is still regarded as the most important determinant of cerebral perfusion and the most relevant hemodynamic management target parameter by most (pediatric) anesthetists. The principle of NIRS monitoring is not self-explanatory and sometimes seems even counterintuitive, which may explain why many anesthesiologists are reserved regarding its use. The first part of this paper is dedicated to a clinical introduction to NIRS monitoring. Despite scientific efforts, it has not yet been possible to define individual lower limit c-rSO2 values and it is unlikely this will succeed in the near future. Nonetheless, published treatment algorithms usually specify c-rSO2 values which may be associated with cerebral hypoxia. Our treatment guideline for maintaining sufficient cerebral oxygenation differs fundamentally from all previously published approaches. We define a baseline c-rSO2 value, registered in the awake child prior to anesthesia induction, as the lowest acceptable limit during anesthesia and surgery. The cerebral rSO2 is the single target parameter, while blood pressure, heart rate, Pa CO2 , and SaO2 are major parameters that determine the c-rSO2. Cerebral NIRS monitoring, interpreted together with its continuously available contributing parameters, may help avoid potentially harmful episodes of cerebral desaturation in anesthetized pediatric patients.

Sleep apnea syndrome caused lowering of cerebral oxygenation in a hemodialysis patient: a case report and literature review

BackgroundSleep apnea syndrome (SAS) is a sleep disturbance, which is frequently comorbid in dialysis patients. SAS induces hypoxia, and therefore, systemic and cerebral oxygenation would be low. Near-infrared spectroscopy (NIRS) has recently been used to measure regional saturation of oxygen (rSO2), as a marker of tissue oxygenation. Although cerebral rSO2 was measured in patients in various clinical settings, few reports have previously shown the associations of changes in cerebral rSO2 and systemic oxygenation using measurement of peripheral arterial oxygen saturation (SpO2) in patients undergoing hemodialysis (HD) with SAS. We herein report a first HD case with SAS-induced reduction in cerebral oxygenation during sleep.Case presentationA 74-year-old woman underwent HD therapy for 1 month, because of advanced CKD caused by hypertension and obesity. In addition, she was diagnosed with obstructive sleep apnea with polysomnography about 4 years prior. Her apnea-hypopnea index (AHI) was 77.5 per hour, and therefore, continuous positive airway pressure (CPAP) was started. Thereafter, her AHI was improved to 3 to 6 per hour. However, she discontinued CPAP therapy at HD initiation. Since her oxygenation without CPAP would deteriorate, we evaluated her SpO2 and cerebral rSO2 by NIRS monitoring during sleep. We confirmed the deterioration in cerebral rSO2 according to the SpO2 decrease, and furthermore, the improvement in cerebral rSO2 was apparently delayed even after the improvement in her SpO2. The patient’s cerebral oxygenation under CPAP therapy could not be evaluated because she refused to receive CPAP therapy after HD initiation. Therefore, as a comparison, we evaluated a 69-year-old male HD patient without SAS and found that in contrast to a patient with SAS, his SpO2 and cerebral rSO2 were maintained throughout sleep.ConclusionWe observed deterioration in cerebral oxygenation during sleep in addition to a decrease in systemic oxygenation in a patient with SAS undergoing HD. Real-time cerebral NIRS monitoring during sleep might be a useful method for detection of SAS.

Ubiquitin C-Terminal Hydrolase 1 and Phosphorylated Axonal Neurofilament Heavy Chain in Infants Undergoing Cardiac Surgery: Preliminary Assessment as Potential Biomarkers of Brain Injury.

There are no reliable markers to assess brain injury in neonates following cardiac surgery. We examine ubiquitin C-terminal hydrolase 1 (UCHL1) and phosphorylated axonal neurofilament heavy chain (pNF-H), neuronal-specific biomarkers released following axonal and cortical injury, in neonates undergoing cardiac surgery involving cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). Twenty-six patients younger than three months were prospectively enrolled (CPB only, n = 12 and DHCA, n = 14). Healthy newborns (n = 22) served as the control. Blood samples were collected preoperatively and postoperatively upon intensive care unit admission (hour 0) and subsequently at 12, 24, 36, and 48 hours. Serum was tested for UCHL1 and pNF-H using enzyme-linked immunosorbent assay. Concomitant arterial blood gas, lactate, and cerebral near-infrared spectroscopy (NIRS) monitoring were performed. Ubiquitin C-terminal hydrolase 1 showed a significant rise at 0 hours in the DHCA group compared to baseline (74.9 ± 13.7 pg/mL vs 33.9 ± 37.3 pg/mL, P < .0001). Levels returned to baseline at 12 hours. There was an early rise in UCHL1 at 0 hours in the CPB group, P = .09. Phosphorylated axonal neurofilament heavy chain was decreased at 0 hours in both the CPB and DHCA groups compared to baseline, P = .06. There was no difference between control and baseline levels of UCHL1 ( P = .9) or pNF-H ( P = .77). Decreased NIRS was observed in the DHCA group at 0 hours (57.3 ± 10.5) versus baseline (64.2 ± 12.3), but not significant ( P = .21). There was no correlation between biomarkers and NIRS at 0 hours. A rapid rise in UCHL1 levels was observed in the DHCA group, suggesting that it may be a marker for acute brain injury. Follow-up with neurodevelopmental studies is ongoing.

Cerebral near-infrared spectroscopy monitoring for prevention of brain injury in very preterm infants.

Cerebral injury and long-term neurodevelopmental impairment is common in extremely preterm infants. Cerebral near-infrared spectroscopy (NIRS) enables continuous estimation of cerebral oxygenation. This diagnostic method coupled with appropriate interventions if NIRS is out of normal range (that is cerebral oxygenation within the 55% to 85% range) may offer benefits without causing more harms. Therefore, NIRS coupled with appropriate responses to abnormal findings on NIRS needs assessment in a systematic review of randomised clinical trials and quasi-randomised studies. To evaluate the benefits and harms of interventions that attempt to alter cerebral oxygenation guided by cerebral NIRS monitoring in order to prevent cerebral injury, improve neurological outcome, and increase survival in preterm infants born more than 8 weeks preterm. We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 8), MEDLINE via PubMed (1966 to 10 September 2016), Embase (1980 to 10 September 2016), and CINAHL (1982 to 10 September 2016). We also searched clinical trial databases, conference proceedings, and the reference lists of retrieved articles for randomised clinical trials and quasi-randomised studies. Randomised clinical trials and quasi-randomised clinical studies comparing continuous cerebral NIRS monitoring for at least 24 hours versus blinded NIRS or versus no NIRS monitoring. Two review authors independently selected, assessed the quality of, and extracted data from the included trials and studies. If necessary, we contacted authors for further information. We conducted assessments of risks of bias; risks of design errors; and controlled the risks of random errors with Trial Sequential Analysis. We assessed the quality of the evidence with GRADE. One randomised clinical trial met inclusion criteria, including infants born more than 12 weeks preterm. The trial employed adequate methodologies and was assessed at low risk of bias. One hundred and sixty-six infants were randomised to start continuous cerebral NIRS monitoring less than 3 hours after birth until 72 hours after birth plus appropriate interventions if NIRS was out of normal range according to a guideline versus conventional monitoring with blinded NIRS. There was no effect of NIRS plus guideline of mortality until term-equivalent age (RR 0.50, 95% CI 0.29 to 1.00; one trial; 166 participants). There were no effects of NIRS plus guideline on intraventricular haemorrhages: all grades (RR 0.93, 95% CI 0.65 to 1.34; one trial; 166 participants); grade III/IV (RR 0.57, 95% CI 0.25 to 1.31; one trial; 166 participants); and cystic periventricular leukomalacia (which did not occur in either group). Likewise, there was no effect of NIRS plus guideline on the occurrence of a patent ductus arteriosus (RR 1.96, 95% CI 0.94 to 4.08; one trial; 166 participants); chronic lung disease (RR 1.27, 95% CI 0.94 to 1.50; one trial; 166 participants); necrotising enterocolitis (RR 0.83, 95% CI 0.33 to 1.94; one trial; 166 participants); and retinopathy of prematurity (RR 1.64, 95% CI 0.75 to 3.00; one trial; 166 participants). There were no serious adverse events in any of the intervention groups. NIRS plus guideline caused more skin marks from the NIRS sensor in the control group than in the experimental group (unadjusted RR 0.31, 95% CI 0.10 to 0.92; one trial; 166 participants). There are no data regarding neurodevelopmental outcome, renal impairment or air leaks.The quality of evidence for all comparisons discussed above was assessed as very low apart from all-cause mortality and adverse events: these were assessed as low and moderate, respectively. The validity of all comparisons is hampered by a small sample of randomised infants, risk of bias due to lack of blinding, and indirectness of outcomes. The only eligible randomised clinical trial did not demonstrate any consistent effects of NIRS plus a guideline on the assessed clinical outcomes. The trial was, however, only powered to detect difference in cerebral oxygenation, not morbidities or mortality. Our systematic review did not reach sufficient power to prove or disprove effects on clinical outcomes. Further randomised clinical trials with low risks of bias and low risks of random errors are needed.

Perioperative Near-Infrared Spectroscopy Monitoring in Neonates With Congenital Heart Disease: Relationship of Cerebral Tissue Oxygenation Index Variability With Neurodevelopmental Outcome.

To evaluate the value of perioperative cerebral near-infrared spectroscopy monitoring using variability analysis in the prediction of neurodevelopmental outcomes in neonates undergoing surgery for congenital heart disease. Retrospective cohort study. Urban, academic, tertiary-care children's hospital. Neonates undergoing surgery with cardiopulmonary bypass for congenital heart disease. Perioperative monitoring of continuous cerebral tissue oxygenation index by near-infrared spectroscopy and subsequent neurodevelopmental testing at 6, 15, and 21 months of age. We developed a new measure, cerebral tissue oxygenation index variability, using the root mean of successive squared differences of averaged 1-minute cerebral tissue oxygenation index values for both the intraoperative and first 24-hours postoperative phases of monitoring. There were 62 neonates who underwent cerebral tissue oxygenation index monitoring during surgery for congenital heart disease and 44 underwent subsequent neurodevelopmental testing (12 did not survive until testing and six were lost to follow-up). Among the 44 monitored patients who underwent neurodevelopmental testing, 20 (45%) had abnormal neurodevelopmental indices. Patients with abnormal neurodevelopmental indices had lower postoperative cerebral tissue oxygenation index variability when compared with patients with normal indices (p = 0.01). Adjusting for class of congenital heart disease and duration of deep hypothermic circulatory arrest, lower postoperative cerebral tissue oxygenation index variability was associated with poor neurodevelopmental outcome (p = 0.02). We found reduced postoperative cerebral tissue oxygenation index variability in neonatal survivors of congenital heart disease surgery with poor neurodevelopmental outcomes. We hypothesize that reduced cerebral tissue oxygenation index variability may be a surrogate for impaired cerebral metabolic autoregulation in the immediate postoperative period. Further research is needed to investigate clinical implications of this finding and opportunities for using this measure to drive therapeutic interventions.

Is NIRS monitoring well tolerated in term and preterm neonates?

Background. Near infrared spectroscopy (NIRS) is a new, non-invasive monitoring method in neonates, which has now be-come part of routine monitoring in many neonatal intensive care units (NICU). New, additional, non-invasive technical moni-toring might have an influence on neonatal wellbeing.Objectives. The aim of the present study was to evaluate the wellbeing of neonates during peripheral and cerebral NIRS mon-itoring and venous occlusions.Methods. In the present study, secondary outcome parameters of prospective ob-servational studies with NIRS in term and preterm neonates were analysed. Heart rate (HR), arterial oxygen saturation (SpO2), respiratory rate (RR), mean arterial blood pressure (MABP), pain score and skin condition at four defined time points dur-ing NIRS measurements of regional tissue oxygenation were recorded and analysed. Results. Thirty-six term and preterm neo-nates were included (gestational age (GA) 36±1 week, 2779±930g birth weight). SpO2 and peripheral tissue oxygenation index (pTOI) increased and HR dropped while RR, mean MABP and pain scores re-mained unchanged during NIRS measure-ments. In eight infants, a mildly irritated area of skin was noted where the NIRS sen-sors had been attached.Conclusion. Cerebral and peripheral NIRS monitoring and venous occlusions were painless and well tolerated by term and preterm neonates.

A retrospective study about cerebral near-infrared spectroscopy monitoring during paediatric cardiac surgery and intra-operative patient blood management

ObjectivesCerebral non-invasive monitoring of oxygen saturation by near-infrared spectroscopy (rSO2) during paediatric cardiac surgery is supposed to decrease the risk of neurological complications. Since haemoglobin level is one of the factors changing rSO2, we aimed to explore if rSO2 monitoring influences intra-operative RBC (red blood cell) transfusion threshold and volumes, as well as the duration of ICU stay. MethodsThe design was a retrospective analysis involving 91 children less than 2 years of age (including 16 neonates) with a congenital heart disease requiring surgical treatment with or without cardiopulmonary bypass from January 2006 to August 2009. Systematic rSO2 monitoring was introduced after September 2007 (n=56). The independent factors associated with the intra-operative transfusion threshold haemoglobin (Hb) level>9.5g/dL, total volume of intra-operative RBC transfusion<30mL/kg and ICU stay<6 days were identified by multivariate analysis logistic regression. Data were expressed as medians (25–75%). ResultsCardiac malformations and demographic characteristics were similar in both periods. Two independent factors, weight and rSO2 monitoring, were identified as independent factors associated with the three end-points. The transfusion threshold, total transfusion volume and ICU stay with and without rSO2 were 9.8 (8.9 to 10.3) versus 8.7 (8.2 to 9.6) g/dL (P<0.0001), 20 (14–49) versus 36 (22.5–51.5) mL/kg (P=0.0165) and 5 (3–8) versus 7 (5–10.7) days (P=0.0084), respectively. ConclusionrSO2 monitoring changed our transfusion strategy with an earlier transfusion but a reduced total RBC volume and decreased the length of ICU stay.

本邦における周術期の近赤外線脳酸素モニター使用の現状

周術期の脳循環代謝モニタリングとして近赤外線脳酸素モニター（NIRS）が使用されているが，現状や有用性は十分に評価されていない．周術期のNIRSの使用状況に関しアンケート調査を実施した．アンケート回収率は38％であった．心臓血管外科全例での使用は38％，不使用が16％であった．不使用の理由は経済的なものが多かった．頸動脈内膜剥離術では47％，頸動脈ステント術では33％の施設で全例に使用していた．頸動脈病変を有したその他の手術にも使用されていた．心臓血管手術，人工心肺使用例，頸動脈内膜剥離術，頸動脈ステント術では有用と評価する施設が多かった．周術期NIRS使用については，適応や管理法などの適正化とともに診療報酬点数の獲得が課題であると考えられた．