Cerebral Near-infrared Spectroscopy Research Articles

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.

Mildly Reduced Doses of Adrenaline Do Not Affect Key Hemodynamic Parameters during Cardio-Pulmonary Resuscitation in a Pig Model of Cardiac Arrest.

Adrenaline is recommended for cardiac arrest resuscitation, but its effectiveness has been questioned recently. Achieving return of spontaneous circulation (ROSC) is essential and is obtained by increasing coronary perfusion pressure (CPP) after adrenaline injection. A threshold as high as 35 mmHg of CPP may be necessary to obtain ROSC, but increasing doses of adrenaline might be harmful to the brain. Our study aimed to compare the increase in CPP with reduced doses of adrenaline to the recommended 1 mg dose in a pig model of cardiac arrest. Fifteen domestic pigs were randomized into three groups according to the adrenaline doses: 1 mg, 0.5 mg, or 0.25 mg administered every 5 min. Cardiac arrest was induced by ventricular fibrillation; after 5 min of no-flow, mechanical chest compression was resumed. The Wilcoxon test and Kruskal–Wallis exact test were used for the comparison of groups. Fisher’s exact test was used to compare categorical variables. CPP, EtCO2 level, cerebral, and tissue near-infrared spectroscopy (NIRS) were measured. CPP was significantly lower in the 0.25 mg group 90 s after the first adrenaline injection: 28.9 (21.2; 35.4) vs. 53.8 (37.8; 58.2) in the 1 mg group (p = 0.008), while there was no significant difference with 0.5 mg 39.6 (32.7; 52.5) (p = 0.056). Overall, 0.25 mg did not achieve the threshold of 35 mmHg. EtCO2 levels were higher at T12 and T14 in the 0.5 mg than in the standard group: 32 (23; 35) vs. 19 (16; 26) and 26 (20; 34) vs. 19 (12; 22) (p < 0.05). Cerebral and tissue NIRS did not show a significant difference between the three groups. CPP after 0.5 mg boluses of adrenaline was not significantly different from the recommended 1 mg in our model of cardiac arrest.

Increasing mean arterial pressure or cardiac output in comatose out-of-hospital cardiac arrest patients undergoing targeted temperature management: Effects on cerebral tissue oxygenation and systemic hemodynamics

IntroductionFew data exist on the effects of increasing norepinephrine doses or increasing arterial CO2 (PaCO2) on hemodynamics and cerebral oxygenation in comatose out-of-hospital cardiac arrest (OHCA) patients. MethodsWe prospectively studied 10 resuscitated OHCA-patients undergoing targeted temperature management (36C°). The trial consisted of 5 phases with 20 minutes steady state in-between: Phase 1–4 were increasing doses of norepinephrine to reach targets of mean arterial pressure (MAP). First 65, second 75, third 85, fourth 65 mmHg again. In the fifth phase, MAP was constant while PaCO2 was increased to 6.5–7.3 kPa to increase cardiac output. Primary outcome was cerebral near-infrared spectroscopy (NIRS). Secondary outcomes were hemodynamic variables from Swan-Ganz catheters and blood samples from the radial artery and jugular bulb. ResultsTo reach a MAP at 85 mmHg, norepinephrine was increased from 0.11 ± 0.02 to 0.18 ± 0.02 µg/kg/min (P < 0.001). Norepinephrine uptitration significantly increased systemic vascular resistance (SVR) and pulmonary vascular resistance, without affecting cardiac output, heart rate or cerebral oxygenation.Increasing PaCO2, resulted in a significant increase in cardiac output and cerebral NIRS, but arterial-venous cerebral oxygen-uptake decreased. Norepinephrine demand to keep MAP at 65 mmHg was unaffected by increasing PaCO2. ConclusionsA short-term increase in MAP with norepinephrine in resuscitated comatose cardiac arrest-patients is associated with increased SVR and pulmonary vascular resistance without affecting cardiac output or cerebral NIRS. Increased cardiac output caused by an increase in PaCO2 increased cerebral NIRS, but not cerebral oxygen uptake.

Percutaneous Common Carotid Artery Access for Cardiac Interventions in Infants Does Not Acutely Change Cerebral Perfusion.

Pediatric cardiac interventions via percutaneous common carotid artery (CCA) access have been shown to be safe and effective. However, the impact of placement of a sheath in the carotid artery for interventions on cerebral perfusion is unknown. In this study we used cerebral near-infrared spectroscopy (NIRS) to analyze the effects of percutaneous CCA access for cardiac interventions on cerebral perfusion. This study is a retrospective chart review carried out at a tertiary care center on all pediatric patients who underwent percutaneous cardiac catheterization via carotid artery access from January 2010 to January 2020. All patients who had ipsilateral NIRS recorded on the side of carotid artery access were included. Patients with only partial or no ipsilateral NIRS data were excluded. The primary outcome measure was the change in NIRS upon CCA access; the mean NIRS for 15min before obtaining access was compared to the mean NIRS during the procedure and to the mean NIRS 15min after removal of the CCA sheath. We hypothesized that there would be a significant drop in NIRS values on the side of CCA access. There were 48 catheterizations in the study period where percutaneous CCA was accessed. Of those, 21 catheterizations had complete data and were included in the study. 13 (62%) were of males. The median age was 23days (IQR 7-79). The indications for CCA access were patent ductus arteriosus stent implantation (n = 13; 62%), aortic valvuloplasty (n = 5; 24%), balloon angioplasty of coarctation of aorta (n = 2; 10%), and renal artery angioplasty (n = 1; 4%). In 16 patients (72%), the left common carotid artery was accessed. The median weight of the patients was 3.3kg (IQR 2.8-2.9). The most common sheath size used was 4F, in 16 patients (72%). The mean NIRS prior to the procedure was 67 ± 15%, during the procedure was 68 ± 20%, and after removal of sheath was 68 ± 21%. Paired t test of cerebral NIRS before, during, and after the procedure showed no significant change with CCA access (P = 0.08). No patient in the series had a documented neurologic deficit following the procedure. Percutaneous CCA access was not associated with a decrease in NIRS on the side of the access during the procedure, suggesting there was no significant acute change in cerebral perfusion with CCA access.

Monitoring of near-infrared spectrum values during packed red blood cell transfusion in pediatric intensive care unit.

Packed red blood cell (PRBC) transfusion is one of the most common treatment options in pediatric intensive care unit (PICU) which targets a better cerebral oxygenation. This study aimed to show the cerebral near-infrared spectroscopy (cNIRS) changes during PRBC transfusions in PICU. In this prospective observational study, changes in regional cerebral tissue oxygen saturation (rSO2) in pediatric patients, who required PRBC transfusion were monitored. All the cNIRS and related values were classified as baseline values. The same values were measured and calculated at the end of transfusion and named as 4th-hour values. Further measurements and calculations were made three hours later and named as 7th-hour values. Changes in cNIRS, cerebral tissue fractional oxygen extraction (CTFOE), cNIRS variability index (cNIRS-VI) were compared using Friedman test. A total of 53 PRBC transfusions were monitored. Baseline haemoglobin increased from 6.3 (5.9, 6.7) gr/dL to 8.6 (8.4, 9) gr/dL at the 7th-hour. cNIRS values improved during transfusion (P=0.012), with a concomitant decrease in cNIRS-VI and CTFOE values (P<0.001 and P=0.017 consecutively) CONCLUSION: Our study revealed that there is an increase in cNIRS and related values after transfusion compared to baseline values in critically ill children admitted to a PICU. Age of PRBC did not have an effect on delta-cNIRS or post-transfusion hemoglobin values. There is a moderate correlation between the baseline cNIRS values and delta-cNIRS value after the transfusion.

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).

Increased beat-to-beat variability of cerebral microcirculatory perfusion during atrial fibrillation: a near-infrared spectroscopy study.

Atrial fibrillation (AFib) is associated with cognitive decline/dementia, independently from clinical strokes or transient ischaemic attacks (TIA). Recent in silico data suggested that AFib may induce transient critical haemodynamic events in the cerebral microcirculation. The aim of this study is to use non-invasive spatially resolved cerebral near-infrared spectroscopy (SRS-NIRS) to investigate in vivo beat-to-beat microcirculatory perfusion during AFib and after sinus rhythm (SR) restoration. Cerebral SRS-NIRS with high-frequency sampling (20 Hz) and non-invasive systemic haemodynamic monitoring were recorded before and after elective electrical cardioversion (ECV) for AFib or atrial flutter (AFL). To assess beat-to-beat effects of the rhythm status, the frequency distribution of inter-beat differences in tissue haemoglobin index (THI), a proxy of microcirculatory cerebral perfusion, was compared before and after SR restoration. Fifty-three AFib/AFL patients (mean age 69 ± 8 years, 79% males) were ultimately enrolled. Cardioversion was successful in restoring SR in 51 (96%) patients. In front of a non-significant decrease in arterial blood pressure extreme events between pre- and post-ECV measurements, a significant decrease of both hypoperfusive and hyperperfusive/hypertensive microcirculatory events was observed after SR restoration (P < 0.001 and P = 0.041, respectively). The present is the first in vivo demonstration that SR restoration by ECV significantly reduces the burden of extreme single-beat haemodynamic events in cerebral microcirculation. Future studies are needed to assess whether SR maintenance might slow long-term AFib-correlated cognitive decline/dementia.

A neonatal neuroNICU collaborative approach to neuromonitoring of posthemorrhagic ventricular dilation in preterm infants.

Morbidity and mortality in prematurely born infants have significantly improved due to advancement in perinatal care, development of NeuroNICU collaborative multidisciplinary approaches, and evidence-based management protocols that have resulted from a better understanding of perinatal risk factors and neuroprotective treatments. In premature infants with intraventricular hemorrhage (IVH), the detrimental secondary effect of posthemorrhagic ventricular dilation (PHVD) on the neurodevelopmental outcome can be mitigated by surgical intervention, though management varies considerably across institutions. Any benefit derived from the use of neuromonitoring to optimize surgical timing and technique stands to improve neurodevelopmental outcome. In this review, we summarize (1) the approaches to surgical management of PHVD in preterm infants and outcome data; (2) neuromonitoring modalities and the effect of neurosurgical intervention on this data; (3) our resultant protocol for the monitoring and management of PHVD. In particular, our protocol incorporates cerebral near-infrared spectroscopy (NIRS) and transcranial doppler ultrasound (TCD) to better understand cerebral physiology and to enable the hypothesis-driven study of the management of PHVD. IMPACT: Review of the published literature concerning the use of near-infrared spectroscopy (NIRS) and a cerebral Doppler ultrasound to study the effect of cerebrospinal fluid drainage on infants with posthemorrhagic ventricular dilation. Presentation of our institution's evidence-based protocol for the use of NIRS and cerebral Doppler ultrasound to study the optimal neurosurgical treatment of posthemorrhagic ventricular dilation, an as yet inadequately studied area.

Venipuncture activates the cerebral cortex in children with intellectual disability

ObjectiveTo evaluate the pattern of cortical activation during a painful procedure, such as a venipuncture, in children with intellectual disability and compare it with that of cognitively healthy children.Study design...

Association of Cerebral Oxymetry with Short-Term Outcome in Critically ill Children Undergoing Extracorporeal Membrane Oxygenation.

Acute brain injury (ABI) is a frequent complication of pediatric extracorporeal membrane oxygenation (ECMO) that could be detected by continuous neuromonitoring. Cerebral near-infrared spectroscopy (NIRS) allows monitoring of cerebral oxygenation. To assess whether an impaired cerebral oxygenation was associated with short-term outcome during pediatric ECMO. We conducted a single-center retrospective study in a pediatric intensive care unit. Children under 18years old were included if receiving veno-venous or veno-arterial ECMO with concurrent NIRS monitoring. Cerebral saturation impairment was defined as rScO2 under 50% or 20% from the baseline for desaturation, and above 80%. Cerebral imaging (magnetic resonance imaging or CT scan) was performed in case of neurological concern. A radiologist blinded for patient history identified ABI as any hemorragic or ischemic lesion, then classified as major or minor. Primary endpoint was the outcome at hospital discharge. Poor outcome was defined as death or survival with a pediatric cerebral performance category scale (PCPC) score ≥ 3 and/or a major ABI. Good outcome was defined as survival with a PCPC score ≤ 2 and/or a minor or no ABI. Secondary endpoint was mortality before PICU discharge. Sixty-three patients met inclusion criteria; 48 (76%) had veno-arterial ECMO. Mortality rate was 51%. Forty-eight of sixty-three patients (76%) evolved with a poor outcome, including 20 major ABI. Mean rScO2 in the right/left hemisphere was 73 ± 9%/75 ± 9%. Cerebral desaturation and decline of rScO2 below 20% from the baseline, regardless of side, were each associated with poor outcome (multivariable-adjusted odds ratio (OR), 4 [95%CI 1.2; 15.1], p = 0.03, and 3.9 [95%CI 1.1; 14.9], p = 0.04, respectively), as well as a mean right rScO2 < 70% during the ECMO course (adjusted OR, 5.6 [95%CI 1.3; 34], p = 0.04). Left rSCO2 ≥ 80% was inversely correlated with hospital mortality (adjusted OR of 0.14 [95%CI0.02; 0.8], p = 0.04). Cerebral desaturation attested by NIRS was associated with a poor short-term outcome in children of all ages undergoing ECMO, and rScO2 > 80% seemed to be protective. NIRS monitoring might be included within multimodal neuromonitoring to assess the risk of the brain injury related to pediatric ECMO.

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.

Brain multimodality monitoring in patients suffering from acute aneurysmal subarachnoid hemorrhage: clinical value and complications.

Brain multimodality monitoring measuring brain tissue oxygen pressure, cerebral blood flow, and cerebral near-infrared spectroscopy may help optimize the neurocritical care of patients with aneurysmal subarachnoid hemorrhage and delayed cerebral ischemia. We retrospectively looked for complications associated with the placement of the probes and checked the reliability of the different tools used for multimodality monitoring. In addition, we screened for therapeutic measures derived in cases of pathological values in multimodality monitoring in 26 patients with acute aneurysmal subarachnoid hemorrhage. Computed tomography scans showed minor hemorrhage along with the probes in 12 patients (46.2%). Missing transmission of values was observed in 34.1% of the intended time of measurement for cerebral blood flow probes and 15.5% and 16.2%, respectively, for the two kinds of probes measuring brain tissue oxygen pressure. We identified 744 cumulative alarming values transmitted from multimodality monitoring. The most frequent intervention was modifying minute ventilation (29%). Less frequent interventions were escalating the norepinephrine dosage (19.9%), elevating cerebral perfusion pressure (14.9%) or inspiratory fraction of inspired oxygen (7.5%), transfusing red blood cell concentrates (1.2%), initiating further diagnostics (2.3%) and neurosurgical interventions (1.9%). As well, 355 cases of pathological values had no therapeutic consequence. The reliability of the measuring tools for multimodality monitoring regarding a continuous transmission of values must be improved, particularly for cerebral blood flow monitoring. The overall high rate of missing therapeutic responses to pathological values derived from multimodality monitoring in patients with aneurysmal subarachnoid hemorrhage underlines the need for structured tiered algorithms. In addition, such algorithms are the basic requirement for prospective multicenter studies, which are urgently needed to evaluate the role of multimodality monitoring in treating these patients.

Comparison of bilateral cerebral and somatic tissue oxygenation with near-infrared spectroscopy in cyanotic and acyanotic pediatric patients receiving cardiac surgery.

IntroductionCompromise of tissue oxygenation during surgery is associated with increased mortality and morbidity in the postoperative period in patients with congenital cardiac disorders. It may be monitored with near-infrared spectroscopy (NIRS). We aimed to evaluate the tissue oxygenation and factors which may affect it by bilateral cerebral and somatic NIRS levels during cardiopulmonary bypass and to compare the NIRS values of cyanotic and acyanotic patient groups.Material and methodsTwo groups of patients with cyanotic and acyanotic congenital heart diseases were included in the study. Each group consisted of 15 patients between 0 and 5 years of age. All data were collected following anesthesia induction (T1), the 10th (T2) and 30th min (T3) of cardiopulmonary bypass (CPB), every 30 min during CPB (T4, T5, T6) and 1 h after (TS). Bilateral and somatic NIRS, blood gases, mean arterial pressure, and temperatures were recorded.ResultsLeft and right somatic NIRS values in groups at all measurements did not differ significantly. Left and right cerebral NIRS values at T2 and T3 in cyanotic patients were significantly higher than in acyanotic patients. Mean arterial pressure and lactate levels at T1 and T3 measurements were responsible for left cerebral NIRS changes and mean arterial pressure on right cerebral NIRS values.ConclusionsMonitorization of tissue perfusion has critical importance during CPB of patients with congenital heart defects. Oxygenation may easily and reliably be measured with NIRS. Cerebral and somatic NIRS are more pronounced in cyanotic patients and cerebral NIRS is strongly associated with mean arterial pressure and circulating lactate levels.

Spettroscopia nel vicino infrarosso (NIRS) e alterazioni dell’emodinamica cerebrale in corso di fibrillazione atriale

The growing epidemiological burden of atrial fibrillation (AF) warrants urgent clarification of the mechanisms at the basis of the independent association between the arrhythmia and cognitive decline/dementia. Several mechanisms have been proposed, such as silent cerebral lesions (subclinical ischemia or micro-haemorrages), a chronic reduction in mean cerebral blood flow, AF-associated pro-inflammatory status and cerebral endothelial dysfunction. However, a new hypothesis based on computational da-ta has recently emerged, which claims that AF irregular rhythm itself may promote direct deleterious beat-to-beat effects, which translates into critical hemodynamic events in the distal cerebral circle. To overcome the limitations of the currently adopted techniques in the study of cerebral circle (transcranial Doppler and Arterial Spin Labeling MRI), we recently demonstrated that cerebral near-infrared spectroscopy (NIRS) with high sampling frequency (20 Hz) may provide beat-to-beat hemodynamic in-sights from the cerebral microcirculation, paving the way for the assessment of distal cerebral hemodynamics during AF. Should the computational findings be confirmed, it will be fundamental to evaluate whether the most aggressive rhythm control strate-gies (such as transcatether ablation) may contribute to reduce cognitive burden in AF patients.

Abstract 152: Cerebral Oximetry During Pediatric In-hospital Cardiac Arrest

Introduction: Cerebral near-infrared spectroscopy (NIRS) measuring regional oxygen saturation (rSO 2 ) during cardiopulmonary resuscitation (CPR) is associated with return of spontaneous circulation (ROSC) and survival to hospital discharge (SHD) in adults, with limited data in children. We hypothesized mean cerebral rSO 2 during pediatric in-hospital cardiac arrest (IHCA) would be associated with return of spontaneous circulation (ROSC). Methods: Consecutive case series of pediatric IHCA events with rSO 2 data reported between 2016-2020 by 3 sites to the Pediatric Resuscitation Quality (pediRES-Q) collaborative. We excluded patients with CPR duration ≤2 minutes or who had return of circulation via extracorporeal membrane oxygenation. We calculated mean rSO 2 for duration of CPR and the primary outcome measure was ROSC. Exploratory sensitivity analyses were performed for cutoffs of mean rSO 2 &gt;25, &gt;30, &gt;35, &gt;40 and &gt;50%. Analysis was done using independent samples t test, Exact logistic regression and Fisher’s exact test. Results: Of 36 events (26 index), median age was 3 [IQR 1,7.8] months; 29 (80.5%) had congenital heart disease and 15 (41.7%) had single ventricle (SV) physiology. Median CPR duration was 7.5 [IQR 3.8, 32.2] minutes and 28/36 (77.8%) had ROSC. Mean intra-arrest cerebral rSO 2 was 44.2% (±19.5) for ROSC vs. 37.4% (±15) for non-ROSC group ( p =0.267). Using Exact logistic regression, there was no association found between rSO 2 and ROSC, even after controlling for age, presence of congenital heart disease, and SV physiology. Using mean rSO 2 cutoffs &gt;25, &gt;30, &gt;35, &gt;40, and &gt;50%, we found no significant association with ROSC. We found same result in the SV subgroup. Conclusion: In this small pediatric cohort of predominantly cardiac patients, there was no significant association between cerebral rSO 2 during pediatric cardiac arrest and ROSC, even after controlling for important confounders of age and SV physiology. More extensive studies using larger populations, and evaluating intra-arrest change in cerebral rSO 2 from baseline, are warranted to provide more insight into the possibilities of using rSO 2 to guide CPR.

Potential Relationship between Cerebral Fractional Tissue Oxygen Extraction (FTOE) and the Use of Sedative Agents during the Perioperative Period in Neonates and Infants.

Fractional tissue oxygen extraction (FTOE) by means of cerebral near-infrared spectroscopy (NIRS) provides information about oxygen uptake in the brain. Experimental animal data suggest that sedative agents decrease cerebral oxygen demand. The aim of the present study was to investigate the association between the cerebral FTOE and the use of pre and intraoperative sedative agents in infants aged 1–90 days. Cerebral NIRS was continuously applied during open major non-cardiac surgery in 46 infants. The main outcomes were the mean intraoperative FTOE and the percentage (%) of time of intraoperative hyperoxiaFTOE relative to the total duration of anesthesia. HyperoxiaFTOE was defined as FTOE ≤ 0.1. Cumulative doses of sedative agents (benzodiazepines and morphine), given up to 24 h preoperatively, correlated with the mean intraoperative FTOE (Spearman’s rho = −0.298, p = 0.0440) and were predictive for the % of time of intraoperative hyperoxiaFTOE (β (95% CI) 47.12 (7.32; 86.92)) when adjusted for the patients’ age, type of surgery, preoperative hemoglobin, intraoperative sevoflurane and fentanyl dose, mean intraoperative arterial blood pressure, and end-tidal CO2 by multivariate 0.75 quantile regression. There was no association with 0.5 quantile regression. We observed the suggestive positive association of decreased fractional cerebral tissue oxygen extraction and the use of sedative agents in neonates and infants undergoing surgery.

Effect of ventilator modes on neonatal cerebral and peripheral oxygenation using near-infrared spectroscopy.

The effect of ventilator modes on regional tissue oxygenation in premature neonates with respiratory distress syndrome (RDS) has yet to be delineated. Previous studies have looked at global oxygen delivery and have not assessed the effects on regional tissue oxygenation. Our aim in this study was to assess such tissue oxygenation in premature babies with RDS in relation to differing modes of ventilation using near-infrared spectroscopy (NIRS). In 24 stable preterm infants with RDS, undergoing elective wean in ventilator mode, cerebral and muscle tissue oxygenation were assessed using NIRS. Infants were weaned from high-frequency oscillator or jet ventilator to conventional invasive ventilation (CV) or extubated from CV to non-invasive mechanical ventilation. Data at 30minutes prior and at one hour after change in ventilator mode were compared (paired t test). In babies changed from high-frequency oscillation to CV, jet to CV and CV to non-invasive ventilation, the differences in cerebral NIRS (mean±SD) were 1.7±9.9%, 2.3±5.7% and 2.1±8.4%, respectively. The concomitant changes in muscle NIRS were -2.9±8.5%, 8.1±9.7% and 3.6±22.4%, respectively. No changes were statistically significant. Our data suggest that there is no alteration in regional tissue oxygenation related to ventilator mode in stable preterm infants with improving RDS.

Noninvasive monitoring of central venous oxygen saturation by jugular transcutaneous near-infrared spectroscopy in pediatric patients undergoing congenital cardiac surgery

Background and aimIn patients undergoing congenital cardiac surgery, it is crucial to maintain oxygen demand-consumption balance. Central venous oxygen saturation (ScvO2) is a useful indicator of oxygen demand and consumption balance which is an invasive method. Near-infrared spectroscopy (NIRS) is a noninvasive, continuous monitoring technique that measures regional tissue oxygenation. NIRS that is placed over the internal jugular vein cutaneous area (NIRSijv) has the potential to show ScvO2 indirectly. In this study, we aimed to determine the correlation between ScvO2 with NIRSijv in pediatric patients undergoing congenital cardiac surgery.Materials and methodsFifty children participated in the study. Four patients were excluded for the inability of internal jugular vein (IJV) catheterization due to technical difficulties. After anesthesia induction, NIRS probes were placed on the IJV site with ultrasound guidance for the measurement of continuous transcutaneous oxygen saturation. The catheter insertion was also done through the IJV from the other side using ultrasound guidance. Cerebral oxygenation monitoring was done using NIRS with a single pediatric probe placed on the right forehead. Values of NIRSijv, cerebral NIRS (NIRSc) and ScvO2, were recorded at certain times until postoperative 24th hour.ResultsData were collected at 8 different time points. There was a significant correlation between ScvO2 and NIRSijv in all measurement time points (r = 0.91), (P = 0.001). The mean bias between ScvO2 and NIRSijv was 2.92% and the limits of agreement were from 11% to –5.2%. There was a moderate correlation between ScvO2 and NIRSc (r = 0.45), (P = 0.001). The mean bias between ScvO2 and NIRSc was 2.7% and the limits of agreement were from +26% to –20%.ConclusionIn this study, we found a strong correlation between ScvO2 and NIRS measurements taken from the internal jugular vein site. Accordingly, continuous noninvasive monitoring with transcutaneous NIRSijv can be an alternative method as a trend monitor for the central venous oxygen saturation in pediatric cardiac patients undergoing congenital cardiac surgery.

A Systematic Review of Cerebral Functional Near-Infrared Spectroscopy in Chronic Neurological Diseases-Actual Applications and Future Perspectives.

Background: The management of people affected by age-related neurological disorders requires the adoption of targeted and cost-effective interventions to cope with chronicity. Therapy adaptation and rehabilitation represent major targets requiring long-term follow-up of neurodegeneration or, conversely, the promotion of neuroplasticity mechanisms. However, affordable and reliable neurophysiological correlates of cerebral activity to be used throughout treatment stages are often lacking. The aim of this systematic review is to highlight actual applications of functional Near-Infrared Spectroscopy (fNIRS) as a versatile optical neuroimaging technology for investigating cortical hemodynamic activity in the most common chronic neurological conditions. Methods: We reviewed studies investigating fNIRS applications in Parkinson’s Disease (PD), Alzheimer’s Disease (AD) and Mild Cognitive Impairment (MCI) as those focusing on motor and cognitive impairment in ageing and Multiple Sclerosis (MS) as the most common chronic neurological disease in young adults. The literature search was conducted on NCBI PubMed and Web of Science databases by PRISMA guidelines. Results: We identified a total of 63 peer-reviewed articles. The AD spectrum is the most investigated pathology with 40 articles ranging from the traditional monitoring of tissue oxygenation to the analysis of functional resting-state conditions or cognitive functions by means of memory and verbal fluency tasks. Conversely, applications in PD (12 articles) and MS (11 articles) are mainly focused on the characterization of motor functions and their association with dual-task conditions. The most investigated cortical area is the prefrontal cortex, since reported to play an important role in age-related compensatory mechanism and neurofunctional changes associated to these chronic neurological conditions. Interestingly, only 9 articles applied a longitudinal approach. Conclusion: The results indicate that fNIRS is mainly employed for the cross-sectional characterization of the clinical phenotypes of these pathologies, whereas data on its utility for longitudinal monitoring as surrogate biomarkers of disease progression and rehabilitation effects are promising but still lacking.

Results of Less Than 5-mm Right Ventricle-Pulmonary Artery Conduits in Single Ventricle Palliation

Our programmatic approach to single ventricle (SV) neonatal palliation has evolved to using smaller-size right ventricle to pulmonary artery (RV-PA) conduits for pulmonary blood flow. Therefore, we sought to compare the early outcomes of less than 5-mm versus 5-mm RV-PA conduits in SV patients undergoing neonatal palliation. We performed a retrospective review of SV patients who had neonatal palliation with either a less than 5-mm or 5-mm RV-PA connection, constructed using a waterproof, breathable fabric membrane graft (Gore-Tex, Flagstaff, AZ). Data before, during, and after surgery were analyzed using SPSS software. A total of 26 patients in group 1 (n= 11; <5 mm) and group 2 (n= 15; 5 mm) were operated on, with a mean follow-up of 13 months. Statistical differences (P ≤ .05) were noted with renal near-infrared spectroscopy (mean, 56 versus 44), and oxygen saturation at discharge (mean, 80% versus 85%) in groups 1 and 2, respectively. We found no significant difference in patient weight, peak lactate, cerebral near-infrared spectroscopy, length of intubation, length of hospitalization, or need for RV-PA conduit intervention after stage 1 along with age, branch PA sizes, or need for PA plasty at bidirectional Glenn between groups. Our early results of less than 5-mm conduits support further exploration into the tailoring of the RV-PA conduit size for each patient. A smaller-diameter conduit may improve systemic cardiac output and net oxygen delivery. Larger patient cohorts and longer follow-up with assessment of pulmonary artery growth are warranted to guide clinical practice.