Validation of Indirect Calorimetry in Children Undergoing Single-Limb Non-Invasive Ventilation: A Proof of Concept, Cross-Over Study.

BACKGROUND: The accurate assessment of resting energy expenditure (REE) is essential for personalized nutrition, particularly in critically ill children. Indirect calorimetry (IC) is the gold standard for measuring REE. This methodology is based on the measurement of oxygen consumption (VO2) and carbon dioxide production (VCO2). These parameters are integrated into the Weir equation to calculate REE. Additionally, IC facilitates the determination of the respiratory quotient (RQ), offering valuable insights into a patient's carbohydrate and lipid consumption. IC validation is limited to spontaneously breathing and mechanically ventilated patients, but it is not validated in patients undergoing non-invasive ventilation (NIV). This study investigates the application of IC during NIV-CPAP (continuous positive airway pressure) and NIV-PS (pressure support). METHODS: This study was conducted in the Pediatric Intensive Care Unit of IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, between 2019 and 2021. Children < 6 years weaning from NIV were enrolled. IC was performed during spontaneous breathing (SB), NIV-CPAP, and NIV-PS in each patient. A Bland-Altman analysis was employed to compare REE, VO2, VCO2, and RQ measured by IC. RESULTS: Fourteen patients (median age 7 (4; 18) months, median weight 7.7 (5.5; 9.7) kg) were enrolled. The REE, VO2, VCO2, and RQ did not differ significantly between the groups. The Limits of Agreement (LoA) and bias of REE indicated good agreement between SB and NIV-CPAP (LoA +28.2, -19.4 kcal/kg/day; bias +4.4 kcal/kg/day), and between SB and NIV-PS (LoA -22.2, +23.1 kcal/kg/day; bias 0.4 kcal/kg/day). CONCLUSIONS: These preliminary findings support the accuracy of IC in children undergoing NIV. Further validation in a larger cohort is warranted.

Cerebrospinal fluid and arterial acid-base equilibria in spontaneously breathing third-trimester pregnant women.

BACKGROUND: Acid-base status in full-term pregnant women is characterised by hypocapnic alkalosis. Whether this respiratory alkalosis is primary or consequent to changes in CSF electrolytes is not clear. METHODS: We enrolled third-trimester pregnant women (pregnant group) and healthy, non-pregnant women of childbearing age (controls) undergoing spinal anaesthesia for Caesarean delivery and elective surgery, respectively. Electrolytes, strong ion difference (SID), partial pressure of carbon dioxide ( [Formula: see text] ), and pH were measured in simultaneously collected CSF and arterial blood samples. RESULTS: All pregnant women (20) were hypocapnic, whilst only four (30%) of the controls (13) had an arterial [Formula: see text] <4.7 kPa (P<0.001). The incidence of hypocapnic alkalosis was higher in the pregnant group (65% vs 8%; P=0.001). The CSF-to-plasma Pco2 difference was significantly higher in pregnant women (1.5 [0.3] vs 1.0 [0.4] kPa; P<0.001), mainly because of a decrease in arterial Pco2 (3.9 [0.3] vs 4.9 [0.5] kPa; P<0.001). Similarly, the CSF-to-plasma difference in SID was less negative in pregnant women (-7.8 [1.4] vs -11.4 [2.3] mM; P<0.001), mainly because of a decreased arterial SID (31.5 [1.2] vs 36.1 [1.9] mM; P<0.001). The major determinant of the reduced plasma SID of pregnant women was a relative increase in plasma chloride compared with sodium. CONCLUSIONS: Primary hypocapnic alkalosis characterises third-trimester pregnant women leading to chronic acid-base adaptations of CSF and plasma. The compensatory SID reduction, mainly sustained by an increase in chloride concentration, is more pronounced in plasma than in CSF, as the decrease in Pco2 is more marked in this compartment. CLINICAL TRIAL REGISTRATION: NCT03496311.

Artificial Neural Network Algorithms to Predict Resting Energy Expenditure in Critically Ill Children.

INTRODUCTION: Accurate assessment of resting energy expenditure (REE) can guide optimal nutritional prescription in critically ill children. Indirect calorimetry (IC) is the gold standard for REE measurement, but its use is limited. Alternatively, REE estimates by predictive equations/formulae are often inaccurate. Recently, predicting REE with artificial neural networks (ANN) was found to be accurate in healthy children. We aimed to investigate the role of ANN in predicting REE in critically ill children and to compare the accuracy with common equations/formulae. STUDY METHODS: We enrolled 257 critically ill children. Nutritional status/vital signs/biochemical values were recorded. We used IC to measure REE. Commonly employed equations/formulae and the VCO2-based Mehta equation were estimated. ANN analysis to predict REE was conducted, employing the TWIST system. RESULTS: ANN considered demographic/anthropometric data to model REE. The predictive model was good (accuracy 75.6%; R2 = 0.71) but not better than Talbot tables for weight. After adding vital signs/biochemical values, the model became superior to all equations/formulae (accuracy 82.3%, R2 = 0.80) and comparable to the Mehta equation. Including IC-measured VCO2 increased the accuracy to 89.6%, superior to the Mehta equation. CONCLUSIONS: We described the accuracy of REE prediction using models that include demographic/anthropometric/clinical/metabolic variables. ANN may represent a reliable option for REE estimation, overcoming the inaccuracies of traditional predictive equations/formulae.

Cerebral Oxygenation by Near-Infrared Spectroscopy in Infants Undergoing Thoracoscopic Lung Resection.

Background: Thoracoscopic resection is the standard of care for congenital lung malformations (CLMs) in infants. However, there is rising concern that capnothorax may affect cerebral perfusion and oxygenation, carrying potential long-term effects on neurodevelopmental behavior. The aim of our study was to investigate, using near-infrared spectroscopy (NIRS), the regional cerebral oxygenation (CrSO2) in infants undergoing thoracoscopic lung resection; the secondary aim was to assess the relationship between rSO2 and standard monitoring. Methods: In this retrospective study, we reviewed all infants (<1 year old, ASA II) who underwent thoracoscopic CLM resection in double-lung ventilation under fixed capnothorax parameters (5 mmHg of pressure, 1 L/minute flow), standardized anesthetic protocol, standard monitoring, and multisite NIRS in our center. We focused our attention on 8 anesthetic and surgical maneuvers, potentially affecting tissue oxygen saturation. Results: Ten infants met the inclusion criteria. At surgery, median age was 5.5 (4-7) months, median weight 7.2 (6.6-8) kg, median operative time 110 (55-180) minutes, and median capnothorax duration 79 (34-168) minutes. No conversion to open surgery occurred. CrSO2 values remained within clinically accepted values during thoracoscopy, beside a CrSO2 drop >20% of basal value in 1 patient, during capnothorax induction. Renal NIRS added very little to standard monitoring, which appeared generally inadequate to consistently appraise end-organ perfusion. ETCO2 best correlated with CrSO2 variations, suggesting to be able to realistically predict them. Conclusions: The thoracoscopic treatment of CLMs under the given conditions appears well tolerated in infants, pending the continuous adjustment of ventilator settings by an experienced anesthetist, confident with NIRS technology.

The management of pediatric severe traumatic brain injury: Italian Guidelines.

INTRODUCTION: The aim of the work was to update the "Guidelines for the Management of Severe Traumatic Brain Injury" published in 2012, to reflect the new available evidence, and develop the Italian national guideline for the management of severe pediatric head injuries to reduce variation in practice and ensure optimal care to patients. EVIDENCE ACQUISITION: MEDLINE and EMBASE were searched from January 2009 to October 2017. Inclusion criteria were English language, pediatric populations (0-18 years) or mixed populations (pediatric/adult) with available age subgroup analyses. The guideline development process was started by the Promoting Group that composed a multidisciplinary panel of experts, with the representatives of the Scientific Societies, the independent expert specialists and a representative of the Patient Associations. The panel selected the clinical questions, discussed the evidence and formulated the text of the recommendations. The documentarists of the University of Florence oversaw the bibliographic research strategy. A group of literature reviewers evaluated the selected literature and compiled the table of evidence for each clinical question. EVIDENCE SYNTHESIS: The search strategies identified 4254 articles. We selected 3227 abstract (first screening) and, finally included 67 articles (second screening) to update the guideline. This Italian update includes 25 evidence-based recommendations and 5 research recommendations. CONCLUSIONS: In recent years, progress has been made on the understanding of severe pediatric brain injury, as well as on that concerning all major traumatic pathology. This has led to a progressive improvement in the clinical outcome, although the quantity and quality of evidence remains particularly low.

Implementation of noninvasive neurally adjusted ventilatory assist in pediatric acute respiratory failure: a controlled before-after quality improvement study.

BACKGROUNDS: Pediatric noninvasive neurally adjusted ventilatory assist (NIV-NAVA) has been shown to improve patient-ventilator interaction but no data on clinical outcomes are available. Aim of this study was to compare NIV-NAVA with noninvasive pressure support (NIV-PS) in children with acute hypoxemic respiratory failure (AHRF), in a single-center before-after study. A cohort of thirty-four NIV-PS patients (before group) admitted to our PICU within the 2 years prior NAVA introduction was compared with a cohort of thirty children treated with NIV-NAVA during implementation phase (after group). The primary end-point was intubation rate between groups. Days on mechanical ventilation, number of invasive devices, nosocomial infections, PICU/hospital length of stay (LOS), and physiological parameters at 2 and 24 h after admission were considered. RESULTS: Intubation rate was lower in the NIV-NAVA group as compared to the NIV-PS group (p = 0.006). Patients treated with NIV-NAVA required fewer invasive devices (p = 0.032) and had lower incidence of ventilator-acquired pneumonia (p = 0.004) and shorter PICU (p = 0.032) and hospital LOS (p = 0.013). At 2 h, NIV-NAVA compared with NIV-PS resulted in higher paO2:FIO2 (p = 0.017), lower paCO2 (p = 0.002), RR (p = 0.026), and HR (p = 0.009). CONCLUSIONS: Early NIV-NAVA vs NIV-PS was associated to lower intubation rate and shorter PICU and hospital LOS. Further studies are needed in order to confirm these preliminary data.

The coagulation profile as a marker for acute appendicitis in the paediatric population: Retrospective study.

INTRODUCTION: Appendicitis is the commonest and most frequently misdiagnosed acute abdominal surgical illness in the paediatric population worldwide. The aim of this study is to evaluate the role of coagulation profile in acute appendicitis (AA) in children. MATERIALS AND METHODS: we retrospectively collected data of patients submitted to appendectomy from 2011 to 2017. According to histopathology, patients were divided into three groups: not histologically confirmed AA (NAA), simple AA (SAA) and complicated AA (CAA). White blood cell (WBC) count, relative neutrophilia (Neutr%), C-reactive protein (CRP), prothrombin time ratio (PTratio), activated partial thromboplastin time ratio (APTTratio) and fibrinogen (Fib) were compared among groups. RESULTS: Three hundred and seven patients were included: 57 NAA, 184 SAA and 66 CAA. WBC was significantly different among groups: CAA (mean 16.67 × 103/ml), SAA (14.73 × 103/ml, P= 0.01) and NAA (10.85 × 103/ml, P< 0.0001). Significant differences were found for Neutr% (mean CAA 81.14 vs. SAA 77.03 P= 0.006, vs. NAA 63.86 P< 0.0001) and CRP (mean NAA 2.56, SAA 3.26, CAA 11.58, P< 0.0001). PTratio and Fib increased with the severity of AA receiver operator characteristic curves were similar for CRP (0.739), Fib (0.726), WBC (0.746) and Neutr% (0.754), while for PTratio and aPTTratio were 0.634 and 0.441, respectively. CONCLUSIONS: extrinsic coagulation pathway is altered in AA, especially in CAA. Coagulation can be useful in the diagnostic and perioperative anaesthetic management of AA in children. Fib seems to have the highest accuracy.

Efficacy and safety of exogenous surfactant therapy in patients under 12 months of age invasively ventilated for severe bronchiolitis (SURFABRON): protocol for a multicentre, randomised, double-blind, controlled, non-profit trial.

INTRODUCTION: Some evidence indicates that exogenous surfactant therapy may be effective in infants with acute viral bronchiolitis, even though more confirmatory data are needed. To date, no large multicentre trials have evaluated the effectiveness and safety of exogenous surfactant in severe cases of bronchiolitis requiring invasive mechanical ventilation (IMV). METHODS AND ANALYSIS: This is a multicentre randomised, placebo-controlled, double-blind study, performed in 19 Italian paediatric intensive care units (PICUs). Eligible participants are infants under the age of 12 months hospitalised in a PICU, suffering from severe acute hypoxaemic bronchiolitis, requiring IMV. We adopted a more restrictive definition of bronchiolitis, including only infants below 12 months of age, to maintain the population as much homogeneous as possible. The primary outcome is to evaluate whether exogenous surfactant therapy (Curosurf, Chiesi Pharmaceuticals, Italy) is effective compared with placebo (air) in reducing the duration of IMV in the first 14 days of hospitalisation, in infants suffering from acute hypoxaemic viral bronchiolitis. Secondary outcomes are duration of non-invasive mechanical ventilation in the post-extubation phase, number of cases requiring new intubation after previous extubation within 14 days from randomisation, PICU and hospital length of stay (LOS), duration of oxygen dependency, effects on oxygenation and ventilatory parameters during invasive mechanical respiratory support, need for repeating treatment within 24 hours of first treatment, use of other interventions (eg, high-frequency oscillatory ventilation, nitric oxide, extracorporeal membrane oxygenation), mortality within the first 14 days of PICU stay and before hospital discharge, side effects and serious adverse events. ETHICS AND DISSEMINATION: The trial design and protocol have received approval by the Italian National Agency for Drugs (AIFA) and by the Regional Ethical Committee of Verona University Hospital (1494CESC). Findings will be disseminated through publication in peer-reviewed journals, conference/meeting presentations and media. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov, issue date 22 May 2019. NCT03959384.

Fluid therapy in mechanically ventilated critically ill children: the sodium, chloride and water burden of fluid creep.

BACKGROUND: Fluid therapy is a cornerstone of pediatric intensive care medicine. We aimed at quantifying the load of water, sodium and chloride due to different fluid indications in our pediatric intensive care unit (PICU). We were particularly interested in the role of fluid creep, i.e. fluid administered mainly as the vehicle for drugs, and the association between sodium load and water balance. METHODS: Critically ill children aged ≤3 years and invasively ventilated for ≥48 h between 2016 and 2019 in a single tertiary center PICU were retrospectively enrolled. Need for renal replacement therapy, plasmapheresis or parenteral nutrition constituted exclusion criteria. Quantity, quality and indication of fluids administered intravenously or enterally, urinary output and fluid balance were recorded for the first 48 h following intubation. Concentrations of sodium and chloride provided by the manufacturers were used to compute the electrolyte load. RESULTS: Forty-three patients (median 7 months (IQR 3-15)) were enrolled. Patients received 1004 ± 284 ml of water daily (153 ± 36 ml/kg/day), mainly due to enteral (39%), creep (34%) and maintenance (24%) fluids. Patients received 14.4 ± 4.8 mEq/kg/day of sodium and 13.6 ± 4.7 mEq/kg/day of chloride, respectively. The majority of sodium and chloride derived from fluid creep (56 and 58%). Daily fluid balance was 417 ± 221 ml (64 ± 30 ml/kg/day) and was associated with total sodium intake (r2 = 0.49, p < 0.001). CONCLUSIONS: Critically ill children are exposed, especially in the acute phase, to extremely high loads of water, sodium and chloride, possibly contributing to edema development. Fluid creep is quantitatively the most relevant fluid in the PICU and future research efforts should address this topic in order to reduce the inadvertent water and electrolyte burden and improve the quality of care of critically ill children.

Prediction of Resting Energy Expenditure in Children: May Artificial Neural Networks Improve Our Accuracy?

The inaccuracy of resting energy expenditure (REE) prediction formulae to calculate energy metabolism in children may lead to either under- or overestimated real caloric needs with clinical consequences. The aim of this paper was to apply artificial neural networks algorithms (ANNs) to REE prediction. We enrolled 561 healthy children (2-17 years). Nutritional status was classified according to World Health Organization (WHO) criteria, and 113 were obese. REE was measured using indirect calorimetry and estimated with WHO, Harris-Benedict, Schofield, and Oxford formulae. The ANNs considered specific anthropometric data to model REE. The mean absolute error (mean ± SD) of the prediction was 95.8 ± 80.8 and was strongly correlated with REE values (R2 = 0.88). The performance of ANNs was higher in the subgroup of obese children (101 ± 91.8) with a lower grade of imprecision (5.4%). ANNs as a novel approach may give valuable information regarding energy requirements and weight management in children.

Nusinersen treatment and cerebrospinal fluid neurofilaments: An explorative study on Spinal Muscular Atrophy type 3 patients.

The antisense oligonucleotide Nusinersen has been recently licensed to treat spinal muscular atrophy (SMA). Since SMA type 3 is characterized by variable phenotype and milder progression, biomarkers of early treatment response are urgently needed. We investigated the cerebrospinal fluid (CSF) concentration of neurofilaments in SMA type 3 patients treated with Nusinersen as a potential biomarker of treatment efficacy. The concentration of phosphorylated neurofilaments heavy chain (pNfH) and light chain (NfL) in the CSF of SMA type 3 patients was evaluated before and after six months since the first Nusinersen administration, performed with commercially available enzyme-linked immunosorbent assay (ELISA) kits. Clinical evaluation of SMA patients was performed with standardized motor function scales. Baseline neurofilament levels in patients were comparable to controls, but significantly decreased after six months of treatment, while motor functions were only marginally ameliorated. No significant correlation was observed between the change in motor functions and that of neurofilaments over time. The reduction of neurofilament levels suggests a possible early biochemical effect of treatment on axonal degeneration, which may precede changes in motor performance. Our study mandates further investigations to assess neurofilaments as a marker of treatment response.

Long-term effect of oxycodone/naloxone on the management of postoperative pain after hysterectomy: a randomized prospective study.

BACKGROUND: The analgesic efficacy of oxycodone prolonged-release (PR) combined with naloxone PR (OXN) in postoperative pain management is recognized, however, few studies have examined the efficacy of OXN on pain relief and bowel function following hysterectomy. This study compared the effect of OXN vs. standard treatment for post-operative pain management and bowel function following hysterectomy. METHODS: This randomized prospective study included 83 women who underwent laparoscopic/laparotomic hysterectomy. General anesthesia was induced by propofol (1.5-2 mg/kg), fentanyl (50-100 µg) and rocuronium (0.6-1 mg/kg) and maintained with sevoflurane (MAC 0.8-1) and fentanyl (1-2 µg/kg). Intraoperative analgesia was performed with ketorolac (30 mg), paracetamol (1 g) and morphine (0.1 mg/kg). Postoperative analgesia in the control group (N.=41) included morphine (0.2-0.4 mg/kg/day), whereas the OXN (N.=42) group only received oxycodone (10 mg)/naloxone (5 mg) for the first 48 hours. As rescue analgesic, both groups received paracetamol (3 mg). Bowel Function Index (BFI) and pain numeric rating scales (NRS) were measured at day 0, 1, 2, 3, 5 and 7, whereas vital parameters, rescue medication and side effects were recorded for the first three days only. RESULTS: Bowel function indices were significantly improved in OXN-treated patients at all time points compared to morphine-treated patients. Mean static pain NRS was significantly decreased at day 2 and day 3 and dynamic pain NRS at day 3 in the OXN group. Side effects, rescue analgesic and antiemetics were more frequent in the control group. CONCLUSIONS: Improved pain control, bowel function and reduced side effects were observed with OXN compared to morphine in patients who underwent hysterectomy.

Therapeutic effect of Anakinra in the relapsing chronic phase of febrile infection-related epilepsy syndrome.

Febrile infection-related epilepsy syndrome (FIRES) is a severe epileptic encephalopathy with presumed inflammatory origin and lacking effective treatments. Anakinra is the human recombinant interleukin 1 receptor antagonist clinically used in autoinflammatory or autoimmune conditions. We report a case of FIRES for which the spatial and temporal match between electroencephalography (EEG) and magnetic resonance imaging (MRI) focal alterations provides support for the detrimental synergic interplay between seizures and inflammation that may evolve to permanent focal lesions and progressive brain atrophy in weeks to months. Brain biopsy showed aspects of chronic neuroinflammation with scarce parenchymal lymphocytes. We report the novel evidence that anakinra reduces the relapse of highly recurrent refractory seizures at 1.5 years after FIRES onset. Our evidence, together with previously reported therapeutic effects of anakinra administered since the first days of disease onset, support the hypothesis that interleukin 1ß and inflammation-related factors play a crucial role in seizure recurrence in both the acute and chronic stages of the disease.

Severe diaphragmatic dysfunction with preserved activity of accessory respiratory muscles in a critically ill child: a case report of failure of neurally adjusted ventilatory assist (NAVA) and successful support with pressure support ventilation (PSV).

BACKGROUND: Neurally adjusted ventilatory assist (NAVA) is an alternative to pressure support ventilation (PSV) potentially improving patient-ventilator interaction. During NAVA, diaphragmatic electrical activity (EAdi) is used to trigger the ventilator and perform a proportional respiratory assistance. We present a case in which the presence of severe bilateral diaphragmatic dysfunction led to a failure of NAVA. On the contrary, the preserved activity of the accessory inspiratory muscles allowed a successful respiratory assistance using PSV. CASE PRESENTATION: A 10-year-old girl developed quadriplegia after neurological surgery. Initially, no spontaneous breathing activity was present and volume controlled ventilation was necessary. Two months later spontaneous inspiratory efforts were observed and a maximal negative inspiratory force of - 20 cmH2O was recorded. In addition, a NAVA nasogastric tube was placed. The recorded EAdi signal, despite showing a phasic activity, had a very low amplitude (1-2 µV). Two brief (15 min) breathing trials to compare PSV (pressure support = 8 cmH2O) with NAVA (Gain = 5 cmH2O/µV, inspiratory trigger = 0.3 µV) were performed. On PSV, the patient was well adapted with stable tidal volumes, respiratory rates, minute ventilation, end-tidal and venous carbon dioxide levels. When switched to NAVA, her breathing pattern became irregular and she showed clear sign of increased work of breathing and distress: tidal volume dropped and respiratory rate rose, leading to an increase in total minute ventilation. Nevertheless, end-tidal and venous carbon dioxide rapidly increased (from 49 to 55 mmHg and from 52 to 57 mmHg, respectively). An electromyographic study documented an impairment of the diaphragm with preserved activity of the accessory inspiratory muscles. CONCLUSIONS: We document the failure of mechanical assistance performed with NAVA due to bilateral diaphragmatic dysfunction in a critically ill child. The preserved activity of some accessory respiratory muscles allowed to support the patient effectively with pressure support ventilation, i.e. by applying a pneumatic trigger. The present case underlines (i) the importance of the integrity of the respiratory centers, phrenic nerves and diaphragm in order to perform NAVA and (ii) the possible diagnostic role of EAdi monitoring in complex cases of weaning failure.