Necrotizing Enterocolitis Detection in Premature Infants Using Broadband Optical Spectroscopy

Necrotizing enterocolitis (NEC) is a devastating disease affecting premature infants. Broadband optical spectroscopy (BOS) is a method of noninvasive optical data collection from intra-abdominal organs in premature infants, offering potential for disease detection. Herein, a novel machine learning approach, iterative principal component analysis (iPCA), is developed to select optimal wavelengths from BOS data collected in vivo from neonatal intensive care unit (NICU) patients for NEC classification. Neural network models were trained for classification, with a reduced-feature model distinguishing NEC with an accuracy of 88%, a sensitivity of 89%, and a specificity of 88%. While whole-spectrum models performed the best for accuracy and specificity, a reduced feature model excelled in sensitivity, with minimal cost to other metrics. This research supports the hypothesis that the analysis of human tissue via BOS may permit noninvasive disease detection. Furthermore, a medical device optimized with these models may potentially screen for NEC with as few as seven wavelengths.

The Effect of Breast Milk Odor on Feeding Cues, Transition Time to Oral Feeding, and Abdominal Perfusion in Premature Newborns: A Randomised Controlled Trial

PURPOSE

The present study was conducted to determine the effect of odor stimulation with breast milk (BM) applied to premature newborns before and during enteral feeding on feeding cues, transition time to oral feeding and abdominal perfusion.

DESIGN

This study was a parallel group pretest-post test randomised controlled trial (RCT).

METHODS

The study was conducted in the neonatal intensive care unit (NICU) in Türkiye. Study data were collected from 32 premature newborns between October 2020 and December 2021. Newborns were randomly assigned to either intervention (n = 16) or control (n = 16) groups. Odor stimulation with BM was applied to newborns in the intervention group (IG) before and during enteral feeding for 3 days. Data were collected with the Newborn Information Form, Abdominal Perfusion Follow-up Form, and Feeding Cues Follow-up Form. Yates corrected and Fisher chi-squared test, Mann-Whitney U test, Cohen Kappa statistics, Permanova analysis, and Wilcoxon test were used in the analysis. The study was registered in ClinicalTrials.gov (NCT04843293).

RESULTS

The frequency of feeding cues in newborns who were exposed to the odor of BM, was higher than in the control group (CG) (p < .05). The transition times to oral feeding were similar in newborns in the IG and CG (p > .05). Abdominal perfusion level of newborns in the IG was higher than the CG (p < .05), and the level of abdominal perfusion showed a significant difference in terms of group*time interaction (p < .05).

CONCLUSION

Our findings suggest that odor stimulation with BM will be beneficial in improving the digestive functions of premature newborns.

The application of infrared thermography technology in flap: A perspective from bibliometric and visual analysis

The application of infrared thermography technology (IRT) in flap has become a major focus of research, as it provides a non-invasive, real-time, and quantitative approach for monitoring flap perfusion. In this regard, we conducted a comprehensive visualization and scientometric analysis to systematically summarize and discuss the current state of research in this field. We systematically reviewed publications on the application of IRT in flap procedures from 1999 to 2022, using the Web of Science Core Collection (WoSCC). Through scientometric analysis, we examined annual trends, affiliations, countries, journals, authors, and their relationships, providing insights into current hotspots and future developments in this area. We analysed 522 English studies and found a steady increase in annual publications. The United States and Germany had the highest publication rates, with Beth Israel Deaconess Medical Center and Shanghai Jiaotong University being leading institutions. Notably, Lee BT and Alex Keller emerged as influential authors in this field. Compared to existing techniques, infrared-based technology offers significant advantages for non-invasive monitoring of flap perfusion, including simplicity of operation and objective results. Future trends should focus on interdisciplinary collaborations to develop new infrared devices and achieve intelligent image processing, enabling broader application in various clinical scenarios. This bibliometric study summarizes the progress and landscape of research on 'the Application of infrared thermography technology in flap' over the past two decades, providing valuable insights and serving as a reliable reference to drive further advancements and spark researchers' interest in this field.

Impairment of Mesenteric Perfusion as a Marker of Major Bleeding in Trauma Patients

The majority of potentially preventable mortality in trauma patients is related to bleeding; therefore, early recognition and effective treatment of hemorrhagic shock impose a cardinal challenge for trauma teams worldwide. The reduction in mesenteric perfusion (MP) is among the first compensatory responses to blood loss; however, there is no adequate tool for splanchnic hemodynamic monitoring in emergency patient care. In this narrative review, (i) methods based on flowmetry, CT imaging, video microscopy (VM), measurement of laboratory markers, spectroscopy, and tissue capnometry were critically analyzed with respect to their accessibility, and applicability, sensitivity, and specificity. (ii) Then, we demonstrated that derangement of MP is a promising diagnostic indicator of blood loss. (iii) Finally, we discussed a new diagnostic method for the evaluation of hemorrhage based on exhaled methane (CH₄) measurement. Conclusions: Monitoring the MP is a feasible option for the evaluation of blood loss. There are a wide range of experimentally used methodologies; however, due to their practical limitations, only a fraction of them could be integrated into routine emergency trauma care. According to our comprehensive review, breath analysis, including exhaled CH₄ measurement, would provide the possibility for continuous, non-invasive monitoring of blood loss.

Noninvasive Monitoring to Demonstrate Postoperative Differences in Regional Hemodynamics in Newborn Infants With d-Transposition of the Great Arteries and Hypoplastic Left Heart Syndrome

BACKGROUND

The adequacy of tissue O₂ delivery in infants receiving intensive care is difficult to measure directly. Regional O₂ (rSO₂) and fractional tissue O₂ extraction (FTOE), the ratio of O₂ consumption to O₂ delivery, obtained from newer noninvasive tools, such as near-infrared spectroscopy (INVOS) and microvascular tissue oximetry (T-Stat) can provide important information on the adequacy of tissue oxygenation and aid in managing critically ill infants.

METHODS

We prospectively evaluated differences in rSO₂ and FTOE in 26 infants with hypoplastic left heart syndrome (HLHS) (n = 12) or d-transposition of the great arteries (d-TGA) (n = 14). Continuous noninvasive monitoring of SpO₂, heart rate, and perfusion index with pulse oximetry, cerebral-rSO₂ and renal-rSO₂ with INVOS, and buccal tissue oxygenation using T-Stat were performed during immediate postoperative period for 24 hours.

RESULTS

The SpO₂ and rSO₂ in infants with d-TGA were higher compared with the infants with HLHS at all measured sites (buccal mucosa, cerebral, and renal). Significant regional differences were also observed in FTOE across all infants with the highest at the buccal mucosa tissue level, followed by cerebral and renal measurement sites. As compared with infants with d-TGA, infants with HLHS had higher regional FTOE and heart rate, with a lower arterial O₂ content and perfusion index.

CONCLUSIONS

Our study demonstrates the utility of noninvasive hemodynamic monitoring to assess regional oxygenation and perfusion, as evidenced by significant differences in infants with HLHS and d-TGA, conditions with different circulation physiologies. Such comprehensive monitoring can potentially aid in evaluating treatment strategies aimed at preventing organ damage from O₂ insufficiency.

Is there an association of near-infrared spectroscopy with low cardiac output and adverse outcomes in single-ventricle patients after stage 1 palliation?

Objective

Our primary objective study was to evaluate the association between near-infrared spectroscopy (NIRS) and low cardiac output (LCO) in patients with single-ventricle physiology after stage 1 palliation.

Methods

In this retrospective study, infants ≤6 months of age with single-ventricle physiology who underwent stage 1 palliation were included. Cerebral and renal NIRS values at various time intervals after surgery were compared between patients with low and normal cardiac output. LCO within the first 48 after surgery was defined as per the pediatric cardiac critical care consortium database. NIRS values were also compared with other adverse outcomes such as cardiac arrest, need for extracorporeal membrane oxygenation and mortality. The receiver operative characteristic curve was generated to determine an optimal cut-off NIRS value for detecting LCO.

Results

Ninety-one patients with median (Interquartile range) age of 10 days (6-26) and weight of 3.3 kg (3-3.5) were included in the study. Cerebral NIRS at 1 h (41.2 vs. 49.5; P = 0.002), 6 h (44 vs. 52.2; P = 0.001), and 12 h (51.8 vs. 56; P = 0.025) was significantly lower in the grouP with LCO compared to no LCO. Cerebral NIRS at 6 h was independently associated with LCO (P = 0.018), and cerebral NIRS at 6 h ≤57% had 91% sensitivity and 72% specificity to detect LCO.

Conclusions

Cerebral NIRS ≤57% at 6 h after surgery detected LCO after stage 1 palliation in single-ventricle patients. Cerebral or renal NIRS was not associated with adverse outcomes and therefore, may not be useful in predicting adverse outcomes in this population.

Could Near Infrared Spectroscopy (NIRS) be the new weapon in our fight against Necrotising Enterocolitis?

There is no ideal single gut tissue or inflammatory biomarker available to help to try and identify Necrotising Enterocolitis (NEC) before its clinical onset. Neonatologists are all too familiar with the devastating consequences of NEC, and despite many advances in neonatal care the mortality and morbidity associated with NEC remains significant. In this article we review Near Infrared Spectroscopy (NIRS) as a method of measuring regional gut tissue oxygenation. We discuss its current and potential future applications, including considering its effectiveness as a possible new weapon in the early identification of NEC.

Near-infrared spectroscopy (NIRS) measured tissue oxygenation in neonates with gastroschisis: a pilot study

BACKGROUND

Management of gastroschisis involves either primary or staged closure. Bowel ischemia and abdominal compartment syndrome (ACS) are possible complications that can be related to a method of treatment. NIRS monitoring has never been applied in this group of patients and may allow for earlier detection of complications.

OBJECTIVE

To assess near-infrared spectroscopy (NIRS) monitoring in neonates with gastroschisis for detecting changes in tissue oxygenation (rSO₂) related to bowel reductions or height of bowel in the silo and for detecting tissue ischemia.

METHODS

Patients with gastroschisis and controls underwent continuous multi-channel assessment of oxygenation of the brain (CrSO₂), kidney (RrSO₂) and bowel (GrSO₂) in a prospective pilot study.

RESULTS

Fifteen neonates were treated with primary closure (n = 3) or staged closure (n = 12); two had confirmed bowel ischemia, none developed ACS.There was no significant correlation between height of the bowel and GrSO₂ at apex (p = .72) or base (p = .54) within the silo. During staged reductions there was a clinically non-significant change in RrSO₂ (Δ-2.5%, p = .04), but no significant changes in CrSO₂ (p = .11), and GrSO₂ of apex (p = .97) and base (p = .31). Patients with confirmed ischemia had GrSO₂ that were lower than controls.

CONCLUSIONS

Measuring GrSO₂ through a silo is feasible. Staged reduction seems safe based on NIRS measurements, with minimal effect of hydrostatic pressure on bowel oxygenation. NIRS was able to detect subtle changes in intra-abdominal renal perfusion during reduction and could differentiate healthy and ischemic bowel.

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.

A wireless, skin-interfaced biosensor for cerebral hemodynamic monitoring in pediatric care

The standard of clinical care in many pediatric and neonatal neurocritical care units involves continuous monitoring of cerebral hemodynamics using hard-wired devices that physically adhere to the skin and connect to base stations that commonly mount on an adjacent wall or stand. Risks of iatrogenic skin injuries associated with adhesives that bond such systems to the skin and entanglements of the patients and/or the healthcare professionals with the wires can impede clinical procedures and natural movements that are critical to the care, development, and recovery of pediatric patients. This paper presents a wireless, miniaturized, and mechanically soft, flexible device that supports measurements quantitatively comparable to existing clinical standards. The system features a multiphotodiode array and pair of light-emitting diodes for simultaneous monitoring of systemic and cerebral hemodynamics, with ability to measure cerebral oxygenation, heart rate, peripheral oxygenation, and potentially cerebral pulse pressure and vascular tone, through the utilization of multiwavelength reflectance-mode photoplethysmography and functional near-infrared spectroscopy. Monte Carlo optical simulations define the tissue-probing depths for source-detector distances and operating wavelengths of these systems using magnetic resonance images of the head of a representative pediatric patient to define the relevant geometries. Clinical studies on pediatric subjects with and without congenital central hypoventilation syndrome validate the feasibility for using this system in operating hospitals and define its advantages relative to established technologies. This platform has the potential to substantially enhance the quality of pediatric care across a wide range of conditions and use scenarios, not only in advanced hospital settings but also in clinics of lower- and middle-income countries.

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

Background and aim

In 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 methods

Fifty 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.

Results

Data 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%.

Conclusion

In 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.

Near-Infrared Spectroscopy in Extremely Preterm Infants

With advances in neonatal care, survival of premature infants at the limits of viability has improved significantly. Despite these improvement in mortality, infants born at 22-24 weeks gestation are at a very high risk for short- and long-term morbidities associated with prematurity. Many of these diseases have been attributed to abnormalities of tissue oxygenation and perfusion. Near-infrared spectroscopy utilizes the unique absorption properties of oxyhemoglobin and deoxyhemoglobin to provide an assessment of regional tissue oxygen saturation, which can be used to calculate the fractional tissue oxygen extraction. This allows for a non-invasive way to monitor tissue oxygen consumption and enables targeted hemodynamic management. This mini-review provides a brief and complete overview of the background and physiology of near-infrared spectroscopy, practical use in extremely preterm infants, and potential applications in the neonatal intensive care unit. In this mini-review, we aim to summarize the three primary application sites for near-infrared spectroscopy, disease-specific indications, and available literature regarding use in extremely preterm infants.

Decrease in Cerebral Oxygen Saturation During the 6-Minute Walk Test in Pediatric Pulmonary Arterial Hypertension

This observational study aimed to investigate the relationship between regional cerebral oxygen saturation (rSO₂) during the 6-minute walk test (6-MWT) and the demographic/clinical features of patients with pulmonary arterial hypertension (PAH). Cerebral oxygenation was evaluated during the 6-MWT in 20 pediatric patients with PAH aged ≥ 7 years [13 male, 7 female; median age 12.25 (range 7-18) years]. In all patients, regional cerebral oxygen saturation    (rSO₂), arterial oxygen saturation (SpO₂), and heart rate (HR) were measured using near-infrared spectroscopy (NIRS) for 2 min before the test, during the 6-MWT test, and 2 min after the test. The relationship between the changes in rSO₂, heart rate, and SpO₂ values and clinical and laboratory features was compared statistically. The mean pulmonary arterial pressure (mPAP) was 77 (range 25-126) mmHg, and the median 6-minute walk distance (6-MWD) was 427.5 (300-570) m. The changes in rSO₂ measurements ranged between 3.41 and 21.8%, and 70% of the patients had a greater than 10% decrease in rSO₂ during the test compared with baseline. Eight patients showed a decrease in rSO₂ without SpO₂ changes. The present study demonstrated a significant decrease in cerebral oxygenation in pediatric patients with PAH during the 6-MWT. We hypothesized that using a combination of the 6-MWT and regional cerebral oxygenation monitoring in pediatric patients with PAH in order to evaluate exercise capacity, as a reflection of reduced daily activities, would provide more precise predictive values than the 6-MWT alone.

Children's Emotional Self-Regulation in the Context of Adversity and the Association with Academic Functioning

The aims of this study were to study reciprocal interactions between emotion regulation skills, association of these skills with children's school functioning and how these underlying skills develop in children in the context of adversity. 48 children (mean age = 5 years 8.2 months) were divided into an adversity risk group and a low-risk group. Emotional regulation was assessed via an emotion identification task, a Stroop task and near-infrared spectroscopy. School functioning was documented using the Social Skills Improvement System with parents and teachers. During the Stroop task, there was a difference in the activation of the right Brodmann area 8 in both groups. During the emotion regulation tasks, BA8L and BA9R showed activation and an association with school functioning. These results contribute to the accuracy of cerebral mapping associated with emotion regulation and support its potential contribution in preventive programs aimed at the functioning of children at risk of school difficulties.

Regional tissue oxygenation monitoring in the neonatal intensive care unit: evidence for clinical strategies and future directions

Near-infrared spectroscopy (NIRS)-based monitoring of regional tissue oxygenation (rSO₂) is becoming more commonplace in the neonatal intensive care unit (NICU). While increasing evidence supports rSO₂ monitoring, actual standards for applying this noninvasive bedside technique continue to evolve. This review highlights the current strengths and pitfalls surrounding practical NIRS-based monitoring in the neonatal population. The physiologic background of rSO₂ monitoring is discussed, with attention to understanding oxygen delivery/consumption mismatch and its effects on tissue oxygen extraction. The bedside utility of both cerebral and peripheral rSO₂ monitoring in the NICU is then explored from two perspectives: (1) disease/event-specific "responsive" monitoring and (2) "routine," continuous monitoring. Recent evidence incorporating both monitoring approaches is summarized with emphasis on practical applicability in the NICU. Finally, a future paradigm for a broad-based NIRS monitoring strategy is presented, with attention towards improving personalization of neonatal care and ultimately enhancing long-term outcomes.

Next generation patient monitor powered by in-silico physiology

The goal of this paper is to introduce a next generation patient monitoring technology that relies on objective and continuous data analytics to alleviate the data overload in the critical care unit. The technology provides the foundation for increasing the consistency and efficacy of data use in clinical practice and improving outcomes. This paper presents results for applying the approach to the hemodynamic monitoring of infants immediately following cardiac surgery and demonstrates its efficacy of estimating the probability of inadequate systemic oxygen delivery, which is an essential risk attribute in the management of critically ill patients.

Current monitoring and innovative predictive modeling to improve care in the pediatric cardiac intensive care unit

The objectives of this review are (I) to describe the challenges associated with monitoring patients in the pediatric cardiac intensive care unit (PCICU) and (II) to discuss the use of innovative statistical and artificial intelligence (AI) software programs to attempt to predict significant clinical events. Patients cared for in the PCICU are clinically fragile and at risk for fatal decompensation. Current monitoring modalities are often ineffective, sometimes inaccurate, and fail to detect a deteriorating clinical status in a timely manner. Predictive models created by AI and machine learning may lead to earlier detection of patients at risk for clinical decompensation and thereby improve care for critically ill pediatric cardiac patients.

Prognostic value of cerebral tissue oxygen saturation during neonatal extracorporeal membrane oxygenation

Objectives

Extracorporeal membrane oxygenation support is indicated in severe and refractory respiratory or circulatory failures. Neurological complications are typically represented by acute ischemic or hemorrhagic lesions, which induce higher morbidity and mortality. The primary goal of this study was to assess the prognostic value of cerebral tissue oxygen saturation (StcO₂) on mortality in neonates and young infants treated with ECMO. A secondary objective was to evaluate the association between StcO₂ and the occurrence of cerebral lesions.

Study design

This was a prospective study in infants < 3 months of age admitted to a pediatric intensive care unit and requiring ECMO support.

Measurements

The assessment of cerebral perfusion was made by continuous StcO₂ monitoring using near-infrared spectroscopy (NIRS) sensors placed on the two temporo-parietal regions. Neurological lesions were identified by MRI or transfontanellar echography.

Results

Thirty-four infants <3 months of age were included in the study over a period of 18 months. The ECMO duration was 10±7 days. The survival rate was 50% (17/34 patients), and the proportion of brain injuries was 20% (7/34 patients). The mean StcO₂ during ECMO in the non-survivors was reduced in both hemispheres (p = 0.0008 right, p = 0.03 left) compared to the survivors. StcO₂ was also reduced in deceased or brain-injured patients compared to the survivors without brain injury (p = 0.002).

Conclusion

StcO₂ appears to be a strong prognostic factor of survival and of the presence of cerebral lesions in young infants during ECMO.

Can transcutaneous near infrared spectroscopy detect severe hepatic ischemia: a juvenile porcine model

BACKGROUND

Vascular complications following pediatric liver transplantation occur in 8-10% of cases, and no continuous, non-invasive monitoring for this problem exists. Near infrared spectroscopy (NIRS) allows non-invasive, continuous, transcutaneous assessment of hemoglobin oxygenation (StO₂ ) 1-4 cm below the skin surface.

AIMS

We hypothesized that transcutaneous NIRS would be able to detect severe hepatic ischemia, and tested this in an animal model using 15-20 kg and 5-7 kg juvenile pigs.

MATERIALS AND METHODS

Direct liver surface and transcutaneous hepatic tissue hemoglobin oxygen saturation (StO₂ ) were measured during occlusions of the hepatic artery and portal vein. Changes in hepatic delivery of oxygen (HepDO₂ ) were calculated for each ischemic challenge and compared to changes in direct liver surface (DirHepStO₂ ) and transcutaneous liver StO₂ measurements (CutHepStO₂ ).

RESULTS

In the 15-20 kg animals during complete occlusion, CutHepStO₂ decreased by 6.0(±4.9)%, whilst DirHepStO₂ decreased by 83.7(±7.2)%. In the 5-7 kg animals during complete occlusion, CutHepStO₂ decreased by 27.4(±8.5)%, whilst DirHepStO₂ decreased by 82.8(±4.6)%.

CONCLUSION

Transcutaneous hepatic StO₂ monitoring cannot reliably detect severe hepatic ischemia in a juvenile porcine model, although a stronger and potentially useful signal is seen in 5-7 kg pigs. Trials of this technology should be currently restricted to situations where the organ is less than 1 cm from the skin surface, corresponding to infants of <10 kg.

Vasoactive Drugs and Hemodynamic Monitoring in Pediatric Cardiac Intensive Care: An Italian Survey

BACKGROUND

Little is known about practitioner preference, the availability of technology, and variability in practice with respect to hemodynamic monitoring and vasoactive drug use after congenital heart surgery. The aim of this study was to characterize current hospital practices related to the management of low cardiac output syndrome (LCOS) across Italy.

METHODS

We issued a 22-item questionnaire to 14 Italian hospitals performing pediatric cardiac surgery.

RESULTS

Electrocardiogram, invasive blood pressure, central venous pressure, pulse oximetry, diuresis, body temperature, arterial lactate, and blood gas analysis were identified as routine in hemodynamic monitoring. With regard to advanced hemodynamic monitoring, pulmonary arterial catheter and transpulmonary thermodilution were available in 43% of the centers, uncalibrated pulse contour methods in 29% of the centers, and transesophageal/transthoracic echocardiograms in all of the centers. Dopamine added to milrinone was the most frequent drug regimen for LCOS prevention after cardiopulmonary bypass. Overall, 86% of centers used milrinone alone as the initial treatment for LCOS with elevated systemic vascular resistances and levosimendan, the second preferred choice. In cases of LCOS with low vascular resistance, epinephrine was the first choice (10 centers), dopamine was the second choice (4 centers), followed by vasopressin and norepinephrine (3 centers). For treatment of LCOS with elevated pulmonary resistances, milrinone was the first choice (eight centers), followed by inhaled nitric oxide (five centers).

CONCLUSIONS

The survey shows that advanced hemodynamic monitoring is rarely performed. The most commonly used vasoactive drugs are milrinone, levosimendan, dopamine, epinephrine, vasopressin, and norepinephrine. Guidelines on the topic are warranted.

Toward translating near-infrared spectroscopy oxygen saturation data for the non-invasive prediction of spatial and temporal hemodynamics during exercise

Image-based computational fluid dynamics (CFD) studies conducted at rest have shown that atherosclerotic plaque in the thoracic aorta (TA) correlates with adverse wall shear stress (WSS), but there is a paucity of such data under elevated flow conditions. We developed a pedaling exercise protocol to obtain phase contrast magnetic resonance imaging (PC-MRI) blood flow measurements in the TA and brachiocephalic arteries during three-tiered supine pedaling at 130, 150, and 170 % of resting heart rate (HR), and relate these measurements to non-invasive tissue oxygen saturation [Formula: see text] acquired by near-infrared spectroscopy (NIRS) while conducting the same protocol. Local quantification of WSS indices by CFD revealed low time-averaged WSS on the outer curvature of the ascending aorta and the inner curvature of the descending aorta (dAo) that progressively increased with exercise, but that remained low on the anterior surface of brachiocephalic arteries. High oscillatory WSS observed on the inner curvature of the aorta persisted during exercise as well. Results suggest locally continuous exposure to potentially deleterious indices of WSS despite benefits of exercise. Linear relationships between flow distributions and tissue oxygen extraction calculated from [Formula: see text] were found between the left common carotid versus cerebral tissue [Formula: see text] and the dAo versus leg tissue [Formula: see text]. A resulting six-step procedure is presented to use NIRS data as a surrogate for exercise PC-MRI when setting boundary conditions for future CFD studies of the TA under simulated exercise conditions. Relationships and ensemble-averaged PC-MRI inflow waveforms are provided in an online repository for this purpose.

Perioperative use of cerebral and renal near-infrared spectroscopy in neonates: a 24-h observational study

BACKGROUND

Neonates undergoing surgery and intensive care still carry a significant morbidity and mortality often related to hypoxic/ischemic events; some of which may go undetected by conventional monitoring. Near-infrared spectroscopy (NIRS) is a noninvasive, continuous method of measuring regional tissue oxygen saturation, and may be used to supplement conventional monitoring to improve neonatal perioperative care. However, high costs and lack of evidence regarding improved outcomes have minimized wider perinatal use of NIRS. The aim of this study was to investigate the applicability of NIRS in neonates and premature infants undergoing noncardiac surgeries.

METHOD

Neonates were monitored with both cerebral and renal NIRS for 24 h after induction of anesthesia and compared with systemic blood pressure (BP), peripheral oxygen saturation (SpO2 ), and heart rate (HR).

RESULTS

A total of 23 368 min of data were collected from 21 neonates. NIRS reported cerebral/renal hypoxia 2.8 (±8.3)%/19.3 (±25.4)% of the time intraoperatively and 9.6 (±17.0)%/9.9 (±18.9)% of the time postoperatively. A moderate positive correlation was found between SpO2 and NIRS (φcerebral = 0.371, φrenal = 0.542). BP showed a weaker positive correlation (φcerebral = 0.231, φrenal = 0.246), and HR no correlation (φcerebral = -0.083, φrenal = -0.029). NIRS reported hypoxia two to three times more frequently than SpO2 , and SpO2 readings were 10-15 s delayed compared to NIRS. Furthermore, NIRS appeared effective at detecting postoperative apnea.

CONCLUSION

Near-infrared spectroscopy is an easily applicable technique that appears effective at detecting hypoxic events and postoperative apneas in neonates. The high incidences of regional hypoxia reported by NIRS in this study imply that there is a need for a more specific regional cerebral and renal monitoring. Despite some practical and economical limitations, NIRS may be considered a useful supplement to perinatal perioperative intensive care.

Near-infrared spectroscopy: applications in neonates

Near-infrared spectroscopy (NIRS) offers non-invasive, in-vivo, real-time monitoring of tissue oxygenation. Changes in regional tissue oxygenation as detected by NIRS may reflect the delicate balance between oxygen delivery and consumption. Originally used predominantly to assess cerebral oxygenation and perfusion perioperatively during cardiac and neurosurgery, and following head trauma, NIRS has gained widespread popularity in many clinical settings in all age groups including neonates. However, more studies are required to establish the ability of NIRS monitoring to improve patient outcomes, especially in neonates. This review provides a comprehensive description of the use of NIRS in neonates.

Non invasive monitoring in mechanically ventilated pediatric patients

Cardiopulmonary monitoring is a key component in the evaluation and management of critically ill patients. Clinicians typically rely on a combination of invasive and non-invasive monitoring to assess cardiac output and adequacy of ventilation. Recent technological advances have led to the introduction: of continuous non-invasive monitors that allow for data to be obtained at the bedside of critically ill patients. These advances help to identify hemodynamic changes and allow for interventions before complications occur. In this manuscript, we highlight several important methods of non-invasive cardiopulmonary monitoring, including capnography, transcutaneous monitoring, pulse oximetry, and near infrared spectroscopy.

Separating heart and brain: on the reduction of physiological noise from multichannel functional near-infrared spectroscopy (fNIRS) signals

OBJECTIVE

Functional near-infrared spectroscopy (fNIRS) is an emerging technique for the in vivo assessment of functional activity of the cerebral cortex as well as in the field of brain-computer interface (BCI) research. A common challenge for the utilization of fNIRS in these areas is a stable and reliable investigation of the spatio-temporal hemodynamic patterns. However, the recorded patterns may be influenced and superimposed by signals generated from physiological processes, resulting in an inaccurate estimation of the cortical activity. Up to now only a few studies have investigated these influences, and still less has been attempted to remove/reduce these influences. The present study aims to gain insights into the reduction of physiological rhythms in hemodynamic signals (oxygenated hemoglobin (oxy-Hb), deoxygenated hemoglobin (deoxy-Hb)).

APPROACH

We introduce the use of three different signal processing approaches (spatial filtering, a common average reference (CAR) method; independent component analysis (ICA); and transfer function (TF) models) to reduce the influence of respiratory and blood pressure (BP) rhythms on the hemodynamic responses.

MAIN RESULTS

All approaches produce large reductions in BP and respiration influences on the oxy-Hb signals and, therefore, improve the contrast-to-noise ratio (CNR). In contrast, for deoxy-Hb signals CAR and ICA did not improve the CNR. However, for the TF approach, a CNR-improvement in deoxy-Hb can also be found.

SIGNIFICANCE

The present study investigates the application of different signal processing approaches to reduce the influences of physiological rhythms on the hemodynamic responses. In addition to the identification of the best signal processing method, we also show the importance of noise reduction in fNIRS data.

Preliminary evaluation of near infrared spectroscopy as a method to detect plasma leakage in children with dengue hemorrhagic fever

Background

Dengue viral infections are prevalent in the tropical and sub-tropical regions of the world, resulting in substantial morbidity and mortality. Clinical manifestations range from a self-limited fever to a potential life-threatening plasma leakage syndrome (dengue hemorrhagic fever). The objective of this study was to assess the utility of near infrared spectroscopy (NIRS) measurements of muscle oxygen saturation (SmO₂) as a possible continuous measure to detect plasma leakage in children with dengue.

Methods

Children ages 6 months to 15 years of age admitted with suspected dengue were enrolled from the dengue ward at Queen Sirikit National Institute for Child Health. Children were monitored daily until discharge. NIRS data were collected continuously using a prototype CareGuide Oximeter 1100 with sensors placed on the deltoid or thigh. Daily ultrasound of the chest and a right lateral decubitus chest x-ray the day after defervescence were performed to detect and quantitate plasma leakage in the pleural cavity.

Results

NIRS data were obtained from 19 children with laboratory-confirmed dengue. Average minimum SmO₂ decreased for all subjects prior to defervescence. Average minimum SmO₂ subsequently increased in children with no ultrasound evidence of pleural effusion but remained low in children with pleural effusion following defervescence. Average minimum SmO₂ was inversely correlated with pleural space fluid volume. ROC analysis revealed a cut-off value for SmO₂ which yielded high specificity and sensitivity.

Conclusions

SmO₂ measured using NIRS may be a useful guide for real-time and non-invasive identification of plasma leakage in children with dengue. Further investigation of the utility of NIRS measurements for prediction and management of severe dengue syndromes is warranted.

Splanchnic-cerebral oxygenation ratio (SCOR) values in healthy term infants as measured by near-infrared spectroscopy (NIRS)

PURPOSE

The splanchnic-cerebral oxygenation ratio (SCOR) is a measurement comparing regional tissue oxygen saturation of splanchnic organs and brain tissue. SCOR has been previously proposed as a marker of clinical conditions associated with gut ischemia. Our goal was to determine SCOR values in healthy neonates in their first and second days of life.

METHODS

Prospective observational study measuring SCOR in term neonates in the nursery using near-infrared spectroscopy (NIRS).

RESULTS

Forty-five subjects with a mean gestational age of 39.4 ± 1.3 weeks were included. Mean SCOR on the first day was 0.90 ± 0.16 and 0.97 ± 0.16 on the second day, p = 0.02 (n = 45). No correlation was found between SCOR and gestational age; however, we did find a positive correlation between hour of life and SCOR values (r = 0.28, r(2) = 0.08, p < 0.01, two tails); SCOR appears to stabilize by 36 h.

CONCLUSIONS

Our findings demonstrate SCOR values in healthy neonates consistent with those previously theorized and help to validate it as a diagnostic measure. In addition, we have demonstrated that SCOR values may normally be lower in infants during their first days of life, and this information may be helpful to clinicians using NIRS as a diagnostic tool.

Newer monitoring techniques to determine the risk of necrotizing enterocolitis

Necrotizing enterocolitis affects up to 10% of neonates who are born weighing less than 1500 g. It has a high rate of morbidity and mortality, and predicting infants who will be affected has so far been unsuccessful. In this article, a number of new methods are discussed from the literature to determine if any currently available techniques may allow for the identification of patients who are at increased risk for developing this potentially lethal disease.

[Post-cardiac arrest syndrome in children]

The occurrence of post-cardiac arrest syndrome may lead to death in some children who have recovered from a cardiac arrest. The post-cardiac arrest syndrome includes systemic ischaemia/reperfusion response, brain injury, myocardial dysfunction, and persistence of the precipitating pathology. The main cause of death is brain injury. Management includes strictly control of ventilation, oxygen therapy and haemodynamics associated with protection of the brain against any secondary injury: management of seizures, control of glycaemia and central temperature. Mild hypothermia should be considered in comatose children after cardiac arrest.

Change in regional (somatic) near-infrared spectroscopy is not a useful indicator of clinically detectable low cardiac output in children after surgery for congenital heart defects

OBJECTIVE

Near-infrared spectroscopy correlation with low cardiac output has not been validated. Our objective was to determine role of splanchnic and/or renal oxygenation monitoring using near-infrared spectroscopy for detection of low cardiac output in children after surgery for congenital heart defects.

DESIGN

Prospective observational study.

SETTING

Pediatric intensive care unit of a tertiary care teaching hospital.

PATIENTS

Children admitted to the pediatric intensive care unit after surgery for congenital heart defects.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We hypothesized that splanchnic and/or renal hypoxemia detected by near-infrared spectroscopy is a marker of low cardiac output after pediatric cardiac surgery. Patients admitted after cardiac surgery to the pediatric intensive care unit over a 10-month period underwent serial splanchnic and renal near-infrared spectroscopy measurements until extubation. Baseline near-infrared spectroscopy values were recorded in the first postoperative hour. A near-infrared spectroscopy event was a priori defined as ≥20% drop in splanchnic and/or renal oxygen saturation from baseline during any hour of the study. Low cardiac output was defined as metabolic acidosis (pH <7.25, lactate >2 mmol/L, or base excess ≤-5), oliguria (urine output <1 mL/kg/hr), or escalation of inotropic support. Receiver operating characteristic analysis was performed using near-infrared spectroscopy event as a diagnostic test for low cardiac output. Twenty children were enrolled: median age was 5 months; median Risk Adjustment for Congenital Heart Surgery category was 3 (1-6); median bypass and cross-clamp times were 120 mins (45-300 mins) and 88 mins (17-157 mins), respectively. Thirty-one episodes of low cardiac output and 273 near-infrared spectroscopy events were observed in 17 patients. The sensitivity and specificity of a near-infrared spectroscopy event as an indicator of low cardiac output were 48% (30%-66%) and 67% (64%-70%), respectively. On receiver operating characteristic analysis, neither splanchnic nor renal near-infrared spectroscopy event had a significant area under the curve for prediction of low cardiac output (area under the curve: splanchnic 0.45 [95% confidence interval 0.30-0.60], renal 0.51 [95% confidence interval 0.37-0.65]).

CONCLUSIONS

Splanchnic and/or renal hypoxemia as detected by near-infrared spectroscopy may not be an accurate indicator of low cardiac output after surgery for congenital heart defects.

Evaluation of splanchnic oximetry, Doppler flow velocimetry in the superior mesenteric artery and feeding tolerance in very low birth weight IUGR and non-IUGR infants receiving bolus versus continuous enteral nutrition

BACKGROUND

IUGR infants are thought to have impaired gut function after birth, which may result in intestinal disturbances, ranging from temporary intolerance to the enteral feeding to full-blown NEC.In literature there is no consensus regarding the impact of enteral feeding on intestinal blood flow and hence regarding the best regimen and the best rate of delivering the enteral nutrition.

METHODS/DESIGN

This is a randomized, non-pharmacological, single-center, cross-over study including 20 VLBW infants. Inclusion criteria * Weight at birth ranging: 700-1501 grams * Gestational age up to 25 weeks and 6 days * Written informed consent from parents or guardians Exclusion criteria * Major congenital abnormality * Patients enrolled in other trials * Significant multi-organ failure prior to trial entry * Pre-existing cutaneous disease not allowing the placement of the NIRS' probe. In the first 24 hours of life, between the 48th and 72nd hours of life, and during Minimal Enteral Feeding, all infants' intestinal perfusion will be evaluated with NIRS and a Doppler of the superior mesenteric artery will be executed.At the achievement of an enteral intake of 100 mL/Kg/day the patients (IUGR and NON IUGR separately) will be randomized in 2 groups: Group A (n=10) will receive a feed by bolus (in 10 minutes); then, after at least 3 hours, they will receive the same amount of formula administered in 3 hours. Group B (n=10) will receive a feed administered in 3 hours followed by a bolus administration of the same amount of formula (in 10 minutes) after at least 3 hours. On the randomization day intestinal and cerebral regional oximetry will be measured via NIRS. Intestinal and celebral oximetry will be measured before the feed and 30 minutes after the feed by bolus during the 3 hours nutrition the measurements will be performed before the feed, 30 minutes from the start of the nutrition and 30 minutes after the end of the gavage. An evaluation of blood flow velocity of the superior mesenteric artery will be performed meanwhile. The infants of the Group A will be fed with continuous nutrition until the achievement of full enteral feeding. The infants of the Group B will be fed by bolus until the achievement of full enteral feeding.

DISCUSSION

Evaluations of intestinal oximetry and superior mesenteric artery blood flow after the feed may help in differentiating how the feeding regimen alters the splanchnic blood flow and oxygenation and if the changes induced by feeding are different in IUGR versus NON IUGR infants.

TRIAL REGISTRATION NUMBER

NCT01341236.

Cerebral and mesenteric tissue oxygenation by positional changes in very low birth weight premature infants

AIM

There has been no clear consensus of the appropriate positioning in preterm infants. We aimed to evaluate the changes of cerebral and mesenteric tissue oxygenation in three different positions, by near infrared spectroscopy (NIRS), in stable very low birth weight (VLBW) infants of postnatal >30 days.

METHODS

NIRS monitoring of cerebral and mesenteric tissue oxygenation in three different positions was performed in 29 stable preterm newborns in neonatal intensive care unit (NICU). The patients were observed in three different positions consecutively, each lasting for 4h. The demographic features, cerebral and mesenteric tissue oxygenation with positional changes and feeding periods were recorded.

RESULTS

Mean gestational age, mean birth weight and mean postnatal age of the patients were 27.6±1.7 weeks, 1046±308 g and 42.4±15.7 days, respectively. There were no statistically significant differences in cerebral and mesenteric tissue regional SO(2) values in each position (p=0.954 and p=0.151, respectively). The values of cerebral and mesenteric tissue regional SO(2) before and after feeding did not show any statistically significant difference in each position.

CONCLUSIONS

Clinically stable very low birth weight infants are able to maintain a stable cerebral and mesenteric tissue oxygenation in different positions, both before and after feeding. Positional changes seem to be safe in VLBW stable infants and this influence should be considered in care of these patients in the NICU. Clinical Trials Identification Number: NCT01255189.

Contemporary management of pulmonary and systemic circulations after the Norwood procedure

Hypoplastic left heart syndrome remains one of the most challenging pathologies in pediatric cardiac surgery. The surgical techniques, and anesthetic and intensive care management, have evolved over the last decades, which has resulted in improved outcomes. A central component in the postoperative management of hypoplastic left heart syndrome patients is to achieve an optimal balance between the pulmonary and systemic circulations. This article discusses the contemporary postoperative management of pulmonary and systemic circulations in detail.

Near-infrared spectroscopy in the critical setting

Near-infrared spectroscopy is a noninvasive means of determining real-time changes in regional oxygen saturation of cerebral and somatic tissues. Hypoxic neurologic injuries not only involve devastating effects on patients and their families but also increase health care costs to the society. At present, monitors of cerebral function such as electroencephalograms, transcranial Doppler, jugular bulb mixed venous oximetry, and brain tissue oxygenation monitoring involve an invasive procedure, are operator-dependent, and/or lack the sensitivity required to identify patients at risk for cerebral hypoxia. Although 20th century advances in the understanding and management of resuscitation of critically ill and injured children have focused on global parameters (ie, pulse oximetry, capnography, base deficit, lactate, etc), a growing body of evidence now points to regional disturbances in microcirculation that will lead us in a new direction of adjunctive tissue monitoring and response to resuscitation. In the coming years, near-infrared spectroscopy will be accepted as a way for clinicians to more quickly and noninvasively identify patients with altered levels of cerebral and/or somatic tissue oxygenation and, in conjunction with global physiologic parameters, guide efficient and effective resuscitation to improve outcomes for critically ill and injured pediatric patients.

Computed tomography scan measurement of abdominal wall thickness for application of near-infrared spectroscopy probes to monitor regional oxygen saturation index of gastrointestinal and renal circulations in children

OBJECTIVES

To measure abdominal wall thickness to determine the depth at which the renal vascular bed and mesenteric vascular bed are located, and to determine the appropriate site for placement of near-infrared spectroscopy probes for accurate monitoring regional oxygen saturation index in children.

DESIGN

Abdominal computerized tomography scans in children were used to measure the abdominal wall thickness and to ascertain the location of kidneys.

SETTING

Tertiary care children's hospital.

SUBJECTS

Children 0-18 yrs of age; n = 38.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main mass of the kidneys is located between vertebral levels T12 and L2 on both sides. The left kidney is located about a half-vertebral length higher than the right kidney. Posterior abdominal wall thickness ranged from 6.6 to 115.8 mm (median, 22.1 mm). Posterolateral abdominal wall thickness ranged from 6.7 to 114.5 mm (median, 19.6 mm). Anterior abdominal wall thickness in the supraumbilical level ranged from 3.5 to 62.9 mm (median, 16.0 mm). All abdominal wall thicknesses correlated better with weight of the subjects than their age.

CONCLUSION

Abdominal wall thickness potentially exceeds the sampling depth of currently used near-infrared spectroscopy probes above a certain body size. Application of current near-infrared spectroscopy probes and design of future probes should consider patient size variations in the pediatric population.

Cerebral NIRS as a marker of superior vena cava oxygen saturation in neonates with congenital heart disease

OBJECTIVES

To investigate the correlation between cerebral near-infrared spectroscopy (NIRS) (rSO2c) and superior vena cava venous oxygen saturation (ScvO2) in newborn patients with congenital heart disease (CHD).

BACKGROUND

NIRS is a noninvasive method to monitor hemoglobin oxygen saturation using nonpulsatile oximetry.

METHODS

We retrospectively analyzed perioperative data from 100 newborn patients who underwent cardiac surgery for CHD. rSO2c, ScvO2 from 24 h before to 72 h after surgery were recorded.

RESULTS

rSO2c had a fair correlation with ScvO2 (r 0.37; P <0.001). The relationship between rSO2c and ScvO2 did not change when analyzed between patients with cyanotic or acyanotic CHD. During the preoperative period, rSO2c levels overestimated ScvO2; in the first 18 postoperative hours, rSO2c underestimated ScvO2; after that period, they showed very close trends. Hypocapnia caused rSO2c to underestimate ScvO2; in normocapnic patients, rSO2c-ScvO2 average differences were close to zero; in hypercapnic neonates, rSO2c tended to overestimate ScvO2. The best performance of rSO2c as a surrogate of ScvO2 was found in the venous saturation ranges from 40% to 60% (r 0.3, P: 0.03).

CONCLUSIONS

rSO2c in newborn patients with cyanotic and acyanotic CHD provides a continuous noninvasive information with a fair correlation with ScvO2%: some predictable variables (i.e., time from surgery, carbon dioxide, and venous saturation levels), should guide the operators to adjust rSO2c values in terms of ScvO2. Serial measures of ScvO2 seem recommended to tailor rSO2c information on actual venous saturation percentage.

Near infrared spectroscopy in children at high risk of low perfusion

PURPOSE OF REVIEW

Tissue oximetry has been suggested as a noninvasive tool to continuously monitor and detect states of low body perfusion. This review summarizes recent developments and available data on the use of near infrared spectroscopy (NIRS) in children at risk for low perfusion.

RECENT FINDINGS

During states of low cardiac output, cerebral blood flow and thus cerebral NIRS may be better preserved than in somatic tissue sites. Consequently, sites other than the frontal cerebral cortex have been investigated for a possible correlation with invasive measures of systemic perfusion and oxygenation (e.g. abdomen, flank, and muscle). The abdominal site seems preferable to the flank site NIRS (kidney region) application. In order to increase the sensitivity, specificity, and positive predictive value of tissue oximetry to detect systemic hypoperfusion, multisite NIRS such as a combination of cerebral and somatic site NIRS has been suggested. NIRS has also been used to assess systemic perfusion in patients undergoing first-stage palliation for hypoplastic left heart syndrome.

SUMMARY

Despite shortcomings in the ability of NIRS technology to accurately reflect validated and directly measured parameters of systemic oxygen delivery and blood flow, NIRS can certainly assist in the detection of low-flow states (low cardiac output). Large, randomized, prospective studies with well defined outcome parameters are still missing and warranted in order to clearly define the role of NIRS in children at risk for low perfusion.

Optimal flow rate for antegrade cerebral perfusion

OBJECTIVE

Antegrade cerebral perfusion is widely used in neonatal heart surgery, yet commonly used flow rates have never been standardized. The objective of this study was to determine the antegrade cerebral perfusion flow rate that most closely matches standard cardiopulmonary bypass conditions.

METHODS

Nine neonatal piglets underwent deep hypothermic cardiopulmonary bypass at a total body flow of 100 mL/kg/min (baseline). Antegrade cerebral perfusion was conducted via innominate artery cannulation at perfusion rates of 10, 30, and 50 mL/kg/min in random order. Cerebral blood flow was measured using fluorescent microspheres. Regional oxygen saturation and cerebral oxygen extraction were monitored.

RESULTS

Cerebral blood flow was as follows: baseline, 60 +/- 17 mL/100 g/min; antegrade cerebral perfusion at 50 mL/kg/min, 56 +/- 17 mL/100 g/min; antegrade cerebral perfusion at 30 mL/kg/min, 36 +/- 9 mL/100 g/min; and antegrade cerebral perfusion at 10 mL/kg/min, 13 +/- 6 mL/100 g/min. At an antegrade cerebral perfusion rate of 50 mL/kg/min, cerebral blood flow matched baseline (P = .87), as did regional oxygen saturation (P = .13). Antegrade cerebral perfusion at 30 mL/kg/min provided approximately 60% of baseline cerebral blood flow (P < .002); however, regional oxygen saturation was equal to baseline (P = .93). Antegrade cerebral perfusion at 10 mL/kg/min provided 20% of baseline cerebral blood flow (P < .001) and a lower regional oxygen saturation than baseline (P = .011). Cerebral oxygen extraction at antegrade cerebral perfusion rates of 30 and 50 mL/kg/min was equal to baseline (P = .53, .48) but greater than baseline (P < .0001) at an antegrade cerebral perfusion rate of 10 mL/kg/min. The distributions of cerebral blood flow and regional oxygen saturation were equal in each brain hemisphere at all antegrade cerebral perfusion rates.

CONCLUSION

Cerebral blood flow increased with antegrade cerebral perfusion rate. At an antegrade cerebral perfusion rate of 50 mL/kg/min, cerebral blood flow was equal to baseline, but regional oxygen saturation and cerebral oxygen extraction trends suggested more oxygenation than baseline. An antegrade cerebral perfusion rate of 30 mL/kg/min provided only 60% of baseline cerebral blood flow, but cerebral oxygen extraction and regional oxygen saturation were equal to baseline. An antegrade cerebral perfusion rate that closely matches standard cardiopulmonary bypass conditions is between 30 and 50 mL/kg/min.

Near-infrared spectroscopy monitors: a novel tool for patient safety in the intensive care unit

Medication errors due to adverse incidents with medical devices are a significant contributor to the total number of hospital errors. Unfortunately, there may be no warning when a device fails, and caregivers may not have an opportunity to prevent patient harm as a result. An error of unrecognized interruption of infusions of cardiac medications can cause rapid patient deterioration. In the case presented, near-infrared spectroscopy monitoring alerted caregivers to an otherwise clinically silent error with infused cardiac medications in the intensive care unit and permitted recognition and intervention before patient harm occurred.

Postcardiac arrest syndrome: focus on the brain

PURPOSE OF REVIEW

The field of pediatric cardiac arrest experienced recent advances secondary to multicenter collaborations. This review summarizes developments during the last year and identifies areas for further research.

RECENT FINDINGS

A large retrospective review demonstrated important differences in cause, severity, and outcome of in-hospital vs. out-of-hospital pediatric cardiac arrest. This distinction is relevant to interpretation of retrospective studies that may not distinguish between these entities, and in planning therapeutic clinical trials. Hypothermia was further evaluated as a treatment strategy after neonatal hypoxia and leaders in the field of neonatology recommend universal use of hypothermia in term neonates at risk. In infants and children after cardiac arrest, there are inadequate data to make a specific recommendation. Two retrospective studies evaluating hypothermia in children after cardiac arrest found that it tended to be administered more frequently to sicker patients. However, similar or worse outcomes of patients treated with hypothermia were observed. Use of extracorporeal membrane oxygenation is another emerging area of research in pediatric cardiac arrest, and surprisingly good outcomes have been seen with this modality in some cases.

SUMMARY

Therapeutic hypothermia and extracorporeal membrane oxygenation continue to be the only treatment modalities over and above conventional care for pediatric cardiac arrest. New approaches to monitoring, treatment, and rehabilitation after cardiac arrest remain to be explored.