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.

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.

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.

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.

Change in pulmonary mechanics and the effect on breathing pattern of high flow oxygen therapy in stable hypercapnic COPD.

: We studied the effects of high flow oxygen therapy (HFOT) versus non-invasive ventilation (NIV) on inspiratory effort, as assessed by measuring transdiaphragmatic pressure, breathing pattern and gas exchange. Fourteen patients with hypercapnic COPD underwent five 30-min trials: HFOT at two flow rates, both with open and closed mouth, and NIV, applied in random order. After each trial standard oxygen therapy was reinstituted for 10 min. Compared with baseline, HFOT and NIV significantly improved breathing pattern, although to different extents, and reduced inspiratory effort; however, arterial carbon dioxide oxygen tension decreased but not significantly. These results indicate a possible role for HFOT in the long-term management of patients with stable hypercapnic COPD. TRIAL REGISTRATION NUMBER: NCT02363920.

Acute flaccid myelitis associated with enterovirus-D68 infection in an otherwise healthy child.

BACKGROUND: Reporting new cases of enterovirus (EV)-D68-associated acute flaccid myelitis (AFM) is essential to understand how the virus causes neurological damage and to characterize EV-D68 strains associated with AFM. CASE PRESENTATION: A previously healthy 4-year-old boy presented with sudden weakness and limited mobility in his left arm. Two days earlier, he had an upper respiratory illness with mild fever. At admission, his physical examination showed that the child was febrile (38.5 °C) and alert but had a stiff neck and weakness in his left arm, which was hypotonic and areflexic. Cerebrospinal fluid (CSF) examination showed a mild increase in white blood cell count (80/mm3, 41% neutrophils) and a slightly elevated protein concentration (76 gm/dL). Bacterial culture and molecular biology tests for detecting viral infection in CSF were negative. The patient was then treated with intravenous ceftriaxone and acyclovir. Despite therapy, within 24 h, the muscle weakness extended to all four limbs, which exhibited greatly reduced mobility. Due to his worsening clinical prognosis, the child was transferred to our Pediatric Intensive Care Unit; at admission he was diagnosed with acute flaccid paralysis of all four limbs. Brain magnetic resonance imaging (MRI) was negative, except for a focal signal alteration in the dorsal portion of the medulla oblongata, also involving the pontine tegmentum, whereas spine MRI showed an extensive signal alteration of the cervical and dorsal spinal cord reported as myelitis. Signal alteration was mainly localized in the central grey matter, most likely in the anterior horns. Molecular biology tests performed on nasopharyngeal aspirate and on bronchoalveolar lavage fluid were negative for bacteria but positive for EV-D68 clade B3. Plasmapheresis was performed and corticosteroids and intravenous immunoglobulins were administered. After 4 weeks of treatment, the signs and symptoms of AFM were significantly reduced, although some weakness and tingling remained in the patient's four limbs. MRI acquired after 3 weeks showed that the previously reported alterations were no longer present. CONCLUSION: This case suggests that EV-D68 is a neurotropic agent that can cause AFM and strains are circulating in Europe. EV-D68 disease surveillance is required to better understand EV-D68 pathology and to compare various strains that cause AFM.

EMpowerment of PArents in THe Intensive Care Questionnaire: Translation and Validation in Italian PICUs.

OBJECTIVES: To translate and validate the EMpowerment of PArents in THe Intensive Care questionnaire to measure parent satisfaction and experiences in Italian PICUs. DESIGN: Prospective, multicenter study. SETTING: Four medical/surgical Italian PICUs in three tertiary hospitals. PATIENTS: Families of children, 0-16 years old, admitted to the PICUs were invited to participate. Inclusion criteria were PICU length of stay greater than 24 hours and good comprehension of Italian language by parents/guardians. Exclusion criteria were readmission within 6 months and parents of a child who died in the PICU. INTERVENTIONS: Distribution, at PICU discharge, of the EMpowerment of PArents in THe Intensive Care questionnaire with 65 items divided into five domains and a six-point rating scale: 1 " certainly no" to 6 "certainly yes." MEASUREMENTS AND MAIN RESULTS: Back and forward translations of the EMpowerment of PArents in THe Intensive Care questionnaire between Dutch (original version) and Italian languages were deployed. Cultural adaptation of the instrument was confirmed by a consultation with a representative parent group (n = 10). Totally, 150 of 190 parents (79%) participated in the study. On item level, 12 statements scored a mean below 5.0. The Cronbach's α, measured for internal consistency, on domain level was between 0.67 and 0.96. Congruent validity was measured by correlating the five domains with four gold standard satisfaction measures and showed adequate correlations (rs, 0.41-0.71; p < 0.05). No significant differences occurred in the nondifferential validity testing between three children's characteristics and the domains; excepting parents with a child for a surgical and planned admission were more satisfied on information and organization issues. CONCLUSIONS: The Italian version of the EMpowerment of PArents in THe Intensive Care questionnaire has satisfactory reliability and validity estimates and seems to be appropriate for Italian PICU setting. It is an important instrument providing benchmark data to be used in the process of quality improvement toward the development of a family-centered care philosophy within Italian PICUs.

Accuracy of Prediction Formulae for the Assessment of Resting Energy Expenditure in Hospitalized Children.

BACKGROUND AND AIM: The resting energy expenditure (REE) of ill children is commonly estimated from prediction formulae developed in healthy children. The aim of the present study was to evaluate the accuracy of commonly employed REE prediction formulae versus indirect calorimetry in hospitalized children. METHODS: We performed a cross-sectional study of 236 infants, children, and adolescents consecutively admitted to the Intermediate Care, Nephrology, Intensive Care, Emergency, and Cystic Fibrosis Units of the De Marchi Pediatric Hospital (Milan, Italy) between September 2013 and March 2015. REE was measured by indirect calorimetry and estimated using the World Health Organization (WHO), Harris-Benedict, Schofield, and Oxford formulae. RESULTS: The mean (standard deviation) difference between the estimated and measured REE was: -1 (234) kcal/day for the WHO formula; 82 (286) kcal/day for the Harris-Benedict formula; 2 (215) kcal/day for the Schofield-weight formula; -2 (214) kcal/day for the Schofield-weight and height formula; and -5 (221) kcal/day for the Oxford formula. Even though the WHO, Schofield, and Oxford formulae gave accurate estimates of REE at the population level (small mean bias), all the formulae were not accurate enough to be employed at the individual level (large SD of bias). CONCLUSIONS: The WHO, Harris-Benedict, Schofield, and Oxford formulae should not be used to estimate REE in hospitalized children.

Early Noninvasive Neurally Adjusted Ventilatory Assist Versus Noninvasive Flow-Triggered Pressure Support Ventilation in Pediatric Acute Respiratory Failure: A Physiologic Randomized Controlled Trial.

OBJECTIVE: Neurally adjusted ventilatory assist has been shown to improve patient-ventilator interaction in children with acute respiratory failure. Objective of this study was to compare the effect of noninvasive neurally adjusted ventilatory assist versus noninvasive flow-triggered pressure support on patient-ventilator interaction in children with acute respiratory failure, when delivered as a first-line respiratory support. DESIGN: Prospective randomized crossover physiologic study. SETTING: Pediatric six-bed third-level PICU. PATIENTS: Eighteen children with acute respiratory failure needing noninvasive ventilation were enrolled at PICU admission. INTERVENTIONS: Enrolled children were allocated to receive two 60-minutes noninvasive flow-triggered pressure support and noninvasive neurally adjusted ventilatory assist trials in a crossover randomized sequence. MEASUREMENTS AND MAIN RESULTS: Primary endpoint was the asynchrony index. Parameters describing patient-ventilator interaction and gas exchange were also considered as secondary endpoints. Noninvasive neurally adjusted ventilatory assist compared to noninvasive flow-triggered pressure support: 1) reduced asynchrony index (p = 0.001) and the number of asynchronies per minute for each type of asynchrony; 2) it increased the neuroventilatory efficiency index (p = 0.001), suggesting better neuroventilatory coupling; 3) reduced inspiratory and expiratory delay times (p = 0.001) as well as lower peak and mean airway pressure (p = 0.006 and p = 0.038, respectively); 4) lowered oxygenation index (p = 0.043). No adverse event was reported. CONCLUSIONS: In children with mild early acute respiratory failure, noninvasive neurally adjusted ventilatory assist was feasible and safe. Noninvasive neurally adjusted ventilatory assist compared to noninvasive flow-triggered pressure support improved patient-ventilator interaction.

The Importance of Mortality Risk Assessment: Validation of the Pediatric Index of Mortality 3 Score.

OBJECTIVE: To evaluate the performance of the newest version of the Pediatric Index of Mortality 3 score and compare it with the Pediatric Index of Mortality 2 in a multicenter national cohort of children admitted to PICU. DESIGN: Retrospective, prospective cohort study. SETTING: Seventeen Italian PICUs. PATIENTS: All children 0 to 15 years old admitted in PICU from January 2010 to October 2014. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Eleven thousand one hundred nine children were enrolled in the study. The mean Pediatric Index of Mortality 2 and 3 values of 4.9 and 3.9, respectively, differed significantly (p < 0.05). Overall mortality rate was 3.9%, and the standardized mortality ratio was 0.80 for Pediatric Index of Mortality 2 and 0.98 for Pediatric Index of Mortality 3 (p < 0.05). The area under the curve of the receiver operating characteristic curves was similar for Pediatric Index of Mortality 2 and Pediatric Index of Mortality 3. The Hosmer-Lemeshow test was not significant for Pediatric Index of Mortality 3 (p = 0.21) but was highly significant for Pediatric Index of Mortality 2 (p < 0.001), which overestimated death mainly in high-risk categories. CONCLUSIONS: Mortality indices require validation in each country where it is used. The new Pediatric Index of Mortality 3 score performed well in an Italian population. Both calibration and discrimination were appropriate, and the score more accurately predicted the mortality risk than Pediatric Index of Mortality 2.

Evolution of Noninvasive Mechanical Ventilation Use: A Cohort Study Among Italian PICUs.

OBJECTIVE: To assess how clinical practice of noninvasive ventilation has evolved in the Italian PICUs. DESIGN: National, multicentre, retrospective, observational cohort. SETTING: Thirteen Italian medical/surgical PICUs that participated in the Italian PICU Network. PATIENTS: Seven thousand one-hundred eleven admissions of children with 0-16 years old admitted from January 1, 2011, to December 31, 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cause of respiratory failure, length and mode of noninvasive ventilation, type of interfaces, incidence of treatment failure, and outcome were recorded. Data were compared with an historical cohort of children enrolled along 6 months from November 1, 2006, to April 30, 2007, over the viral respiratory season. Seven thousand one-hundred eleven PICU admissions were analyzed, and an overall noninvasive ventilation use of 8.8% (n = 630) was observed. Among children who were admitted in the PICU without mechanical ventilation (n = 3,819), noninvasive ventilation was used in 585 patients (15.3%) with a significant increment among the three study years (from 11.6% in 2006 to 18.2% in 2012). In the endotracheally intubated group, 17.2% children received noninvasive ventilation at the end of the weaning process to avoid reintubation: 11.9% in 2006, 15.3% in 2011, and 21.6% in 2012. Noninvasive ventilation failure rate raised from 10% in 2006 to 16.1% in 2012. CONCLUSIONS: Noninvasive ventilation is increasingly and successfully used as first respiratory approach in several, but not all, Italian PICUs. The current study shows that noninvasive ventilation represents a feasible and safe technique of ventilatory assistance for the treatment of mild acute respiratory failure. Noninvasive ventilation was used as primary mode of ventilation in children with low respiratory tract infection (mainly in bronchiolitis and pneumonia), in acute on chronic respiratory failure or to prevent reintubation.

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.

Subcutaneous emphysema as the first relevant clinical sign of complicated tubercular lymph node disease in a child.

BACKGROUND: Children make up a significant proportion of the global tuberculosis (TB) caseload, and experience considerable TB-related morbidity and mortality. Unfortunately, it is not easy to diagnose TB in the first years of life because of the diversity of its clinical presentation and the non-specific nature of most of its symptoms. CASE PRESENTATION: A 26-month-old male child was admitted to hospital because of the sudden onset of rapidly increasing swelling of the neck, face and upper trunk a few hours before. Upon admission, his temperature was 36.5°C, pulse rate 120/min, respiratory rate 36/min, and O2 saturation 97% in air. Palpation revealed subcutaneous emphysema (SE) over the swollen skin areas, and an examination of the respiratory system revealed crepitations in the left part of the chest without any significant suggestion of mediastinal shift. Chest radiography showed enlargement of the left lung hilum with pneumomediastinum and diffuse SE. Bronchoscopy was carried out because of the suspicion that the SE may have been due to the inhalation of a peanut. This excluded the presence of a foreign body but showed that the left main bronchus was partially obstructed with caseous material and showed significant signs of granulomatous inflammation on the wall. Contrast-enhanced computed tomography of the lungs confirmed the SE and pneumomediastinum, and revealed bilateral hilum lymph node disease with infiltration of the adjacent anatomical structure and a considerable breach in the left primary bronchus wall conditioning the passage of air in the mediastinum and subcutaneous tissue. As a tuberculin skin test and polymerase chain reaction for Mycobacterium tuberculosis on bronchial material and gastric aspirate were positive, a diagnosis of TB was made and oral anti-TB therapy was started, which led to the elimination of M. tuberculosis and a positive clinical outcome. CONCLUSIONS: This is the first case in which SE was the first relevant clinical manifestation of TB and arose from infiltration of the bronchial wall secondary to caseous necrosis of the hilum lymph nodes. Physicians should be aware of the fact that SE is one of the possible initial signs and symptoms of early TB infection, and act accordingly.

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.

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.

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.

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.