Safely Discharging Infants with Bronchiolitis from an Emergency Department: A Five Step Guide for Pediatricians.

Recent publications have established the pulse oxygen saturation (SpO2) threshold of 90% for the hospitalization and discharge of infant patients with bronchiolitis. However, there is no clear recommendation regarding the Emergency Department (ED) observation period necessary before allowing safe home discharge for patients with SpO2 above 90%-92%. Our primary aims were to evaluate the risk factors associated with delayed desaturation in infants with SpO2 ≥ 92% on arrival at the ED as well as the ED observation period necessary before allowing safe home discharge. A secondary aim was to identify the risk factors for ED readmission. Of 581 episodes of bronchiolitis in patients < 1 year old admitted to the ED, only 47 (8%) had SpO2 < 92% on arrival there, although 106 (18%) exhibited a delayed desaturation (to < 92%) during ED observation. Female sex, age < 3 months old, ED readmission, more severe initial clinical presentation, and higher pCO2 level (> 6KPa) were risk factors for delayed desaturation with OR varying from 1.7 to 7.5. In patients < 3 months old, mean desaturation occured later than in older patients [6.0 hours (IQR 3.0-14.0) vs. 3.0 hours (IQR 2.0-6.0), P = 0.0018]. In 95% of patients with a delayed desaturation this decrease occurred within 25 hours for patients < 3 months old and within 11 hours for patients ≥ 3 months old. In patients < 3 months old with respiratory rates above the normal range for their age the desaturation occurred earlier than in patients < 3 months with normal respiratory rates [4.4 hours (IQR 3.0-11.7) vs. 14.6 hours (IQR 7.6-22.2), P = 0.037]. Based on the present study's results, we propose a five step guide for pediatricians on discharging children with bronchiolitis from the ED. By using the threshold of an 11 hour ED observation period for patients ≥ 3 months old and a 25 hour period for patients < 3 months old we are able to detect 95% of the patients with bronchiolitis who are at risk of delayed desaturation.

Virologic testing in bronchiolitis: does it change management decisions and predict outcomes?

UNLABELLED: The aim of this study was to evaluate the clinical, therapeutic, laboratory, and radiological differences between respiratory syncytial virus (RSV) and non-RSV bronchiolitis in order to assess if the prior knowledge of viral etiology changed management decisions and would be able to predict outcomes. Medical charts of children <1 year admitted to the emergency department with bronchiolitis during two RSV seasons (2010-2012) were reviewed. We analyzed 221 episodes of bronchiolitis. The percentage of exams performed (95 % confidence interval (CI) 0.74-2.52), abnormal laboratory and radiological findings (95 % CI 0.53-16.89) did not differ between groups. RSV bronchiolitis had a more severe clinical course. However, virologic testing for RSV had low specificity in identifying at-risk patients for hospitalization, longer hospital length of stay, and need of oxygen therapy and nasogastric tube (44, 40, 42, and 35 %, respectively), and while statistically significant, the positive likelihood ratios were only slightly greater than 1. CONCLUSION: Although RSV bronchiolitis has a more severe clinical course, virologic testing does not help in management decisions, and at an individual level, as a performance test, it seems insufficient to precisely predict outcomes.

The protective effects of volatile anesthestics against the bronchoconstriction induced by an allergic reaction in sensitized rabbit pups.

BACKGROUND: Volatile inhaled anesthetics exert a differential protective effect against bronchospasm development after cholinergic stimulation. However, their ability to inhibit the adverse respiratory consequences of an anaphylactic reaction after exposure to an allergen has not been characterized. We therefore compared the abilities of isoflurane, sevoflurane, and desflurane to prevent the lung constriction induced by an allergic reaction in a pediatric model of an anaphylactic reaction. METHODS: Low-frequency respiratory input impedance (Zrs) was measured in 4 groups of ovalbumin (OVA)-sensitized 5-week-old rabbit pups anesthetized with midazolam (group IV) and with inhaled isoflurane (group ISO), sevoflurane (group SEVO), or desflurane (group DES) at 1 minimum alveolar concentration. Zrs was measured under baseline conditions and after an anaphylactic lung response provoked by IV allergen injection (OVA 1 mg), during which the changes in airway resistance (Raw), tissue damping (G), and elastance obtained from Zrs were followed for 15 minutes. RESULTS: Allergen provocation generated immediate severe bronchoconstriction, with no statistically significant difference in Raw increase among the groups in the first 3 minutes. Conversely, the inhalation of volatile anesthetics accelerated the recovery from the allergen-induced bronchoconstriction, particularly in group SEVO where the Raw was significantly lower than that in group IV 4 minutes after the allergen challenge. These changes were paralleled by significant elevations in G in all groups, with a significantly more pronounced deterioration in the animals in group DES. The anesthetic regimen did not statistically significantly affect the sustained increases in elastance after OVA injections. CONCLUSIONS: Our results reveal the lack of potential of the commonly used volatile anesthetics to inhibit the most severe acute phase of the constrictor response to allergen after anaphylaxis in both the central airway and peripheral lung compartments. Inhalation of volatile anesthetics, particularly sevoflurane, promotes an earlier easing of the bronchospasm; this beneficial profile may be advantageous in children with atopic lung diseases.

Chest CT in bronchopulmonary dysplasia: clinical and radiological correlations.

BACKGROUND: Chest CT is very sensitive in assessing pulmonary damage in bronchopulmonary dysplasia (BPD) and radiological findings in BPD are well described. Validated CT scores are available to assess BPD, as available in other pulmonary diseases such as cystic fibrosis. AIM: To investigate whether there is a correlation between radiological pulmonary lesions and relevant BPD clinical data (gestational age, type and duration of mechanical ventilation, and severity of BPD) and assess the usefulness of a CT score in evaluating clinical severity. MATERIALS AND METHODS: Retrospective study of 19 premature infants with BPD born between 1998 and 2007 who underwent at least one chest CT during their first year of life. A total of 29 CT were blindly evaluated by two radiologists for the presence or absence of pulmonary parenchymal abnormalities described in BPD (areas of decreased attenuation, presence of bullae/emphysema, bronchial wall thickening, bronchiectasis, linear, and subpleural opacities). This score was then compared with the most relevant clinical data. RESULTS: All CT scans showed abnormalities. The most frequent lesion was bronchial wall thickening observed in all patients, followed by linear (89.5%) and subpleural (89.5%) opacities. Areas of decreased attenuation were found in 68.4%. Bullae/emphysema and bronchiectasis were the less frequent item described (26.3% and 21.1%, respectively). The presence of areas of decreased attenuation significantly correlated with BPD severity (P = 0.03). However, there was no significant correlation between the CT score and clinical data. CONCLUSIONS: This study demonstrates the potential usefulness of chest CT score to assess the severity of BPD. Areas of decreased attenuation seem the most sensitive item to predict BPD severity. More patients are needed to validate this approach and to evaluate the long-term usefulness of CT scan.

CD4+CD25-mTGFbeta+ T cells induced by nasal application of ovalbumin transfer tolerance in a therapeutic model of asthma.

BACKGROUND: Intranasal administration of high amount of allergen was shown to induce tolerance and to reverse the allergic phenotype. However, mechanisms of tolerance induction via the mucosal route are still unclear. OBJECTIVES: To characterize the therapeutic effects of intranasal application of ovalbumin (OVA) in a mouse model of bronchial inflammation as well as the cellular and molecular mechanisms leading to protection upon re-exposure to allergen. METHODS: After induction of bronchial inflammation, mice were treated intranasally with OVA and re-exposed to OVA aerosols 10 days later. Bronchoalveolar lavage fluid (BALF), T cell proliferation and cytokine secretion were examined. The respective role of CD4(+)CD25(+) and CD4(+)CD25(-) T cells in the induction of tolerance was analysed. RESULTS: Intranasal treatment with OVA drastically reduced inflammatory cell recruitment into BALF and bronchial hyperresponsiveness upon re-exposure to allergen. Both OVA- specific-proliferation of T cells, T(h)1 and T(h)2 cytokine production from lung and bronchial lymph nodes were inhibited. Transfer of CD4(+)CD25(-) T cells, which strongly expressed membrane-bound transforming growth factor ß (mTGFß), from tolerized mice protected asthmatic recipient mice from subsequent aerosol challenges. The presence of CD4(+)CD25(+)(Foxp3(+)) T cells during the process of tolerization was indispensable to CD4(+)CD25(-) T cells to acquire regulatory properties. Whereas the presence of IL-10 appeared dispensable in this model, the suppression of CD4(+)CD25(-)mTGFß(+) T cells in transfer experiments significantly impaired the down-regulation of airways inflammation. CONCLUSION: Nasal application of OVA in established asthma led to the induction of CD4(+)CD25(-)mTGFß(+) T cells with regulatory properties, able to confer protection upon allergen re-exposure.

In vivo investigations on anti-fibrotic potential of proteasome inhibition in lung and skin fibrosis.

In systemic sclerosis (SSc), a disease characterized by fibrosis of the skin and internal organs, the occurrence of interstitial lung disease is responsible for high morbidity and mortality. We previously demonstrated that proteasome inhibitors (PI) show anti-fibrotic properties in vitro by reducing collagen production and favoring collagen degradation in a c-jun N-terminal kinase (JNK)-dependent manner in human fibroblasts. Therefore, we tested whether PI could control fibrosis development in bleomycin-induced lung injury, which is preceded by massive inflammation. We extended the study to test PI in TSK-1/+ mice, where skin fibrosis develops in the absence of overt inflammation. C57Bl/6 mice received bleomycin intratracheally and were treated or not with PI. Lung inflammation and fibrosis were assessed by histology and quantification of hydroxyproline content, type I collagen mRNA, and TGF-beta at Days 7, 15, and 21, respectively. Histology was used to detect skin fibrosis in TSK-1/+mice. The chymotryptic activity of 20S proteasome was assessed in mice blood. JNK and Smad2 phosphorylation were evaluated by Western blot on lung protein extracts. PI reduced collagen mRNA levels in murine lung fibroblasts, without affecting their viability in vitro. In addition, PI inhibited the chymotryptic activity of proteasome and enhanced JNK and TGF-beta signaling in vivo. PI failed to prevent bleomycin-induced lung inflammation and fibrosis and to attenuate skin fibrosis in TSK-1/+mice. In conclusion, our results provide direct evidence that, despite promising in vitro results, proteasome blockade may not be a strategy easily applicable to control fibrosis development in diseases such as lung fibrosis and scleroderma.

Poly(ADP-ribose) polymerase-1 (PARP-1) controls lung cell proliferation and repair after hyperoxia-induced lung damage.

Oxygen-based therapies expose lung to elevated levels of ROS and induce lung cell damage and inflammation. Injured cells are replaced through increased proliferation and differentiation of epithelial cells and fibroblasts. Failure to modulate these processes leads to excessive cell proliferation, collagen deposition, fibrosis, and chronic lung disease. Poly(ADP-ribose) polymerase-1 (PARP-1) is activated in response to DNA damage and participates in DNA repair, genomic integrity, and cell death. In this study, we evaluated the role of PARP-1 in lung repair during recovery after acute hyperoxia exposure. We exposed PARP-1 -/- and wild-type mice for 64 h to 100% hyperoxia and let them recover in air for 5-21 days. PARP-1-deficient mice exhibited significantly higher lung cell hyperplasia and proliferation than PARP-1 +/+ animals after 5 and 10 days of recovery. This was accompanied by an increased inflammatory response in PARP-1 -/- compared with wild-type animals, characterized by neutrophil infiltration and increased IL-6 levels in bronchoalveolar lavages. These lesions were reversible, since the extent of the hyperplastic regions was reduced after 21 days of recovery and did not result in fibrosis. In vitro, lung primary fibroblasts derived from PARP-1 -/- mice showed a higher proliferative response than PARP-1 +/+ cells during air recovery after hyperoxia-induced growth arrest. Altogether, these results reveal an essential role of PARP-1 in the control of cell repair and tissue remodeling after hyperoxia-induced lung injury.

Incidence and risk factors of perioperative respiratory adverse events in children undergoing elective surgery.

BACKGROUND: Adverse respiratory events remain one of the major causes of morbidity during anaesthesia, especially in children. The purpose of this prospective study was to determine the incidence of perioperative respiratory adverse events (PRAE) during elective paediatric surgery and to identify the risk factors for these events. METHODS: Potential risk factors (atopy, eczema, rhinitis, food allergy, previous allergic tests, pollens or animal allergy, passive smoking, obstructive sleep disorders) were assessed using the International Society on Allergy and Asthma (ISAAC) questionnaire, which was submitted to the parents during preoperative anaesthetic assessment. Anaesthetic and surgical conditions were systematically recorded. A multivariate logistic regression explaining PRAE was developed in 800 children. RESULTS: The intraoperative incidence of respiratory adverse events was 21% and the incidence in the postanesthetic care unit was 13%. According to the multivariate analysis, children not anaesthetized by a specialist paediatric anaesthesiologist have 1.7 increased risk to present PRAE (95% CI = 1.13-2.57). Children anaesthetized for ear, nose, throat (ENT) surgery had a 1.57-fold higher risk of PRAE compared with other procedures (95% CI = 1.01-2.44). Furthermore, there was a synergistic interaction when two risk factors: residents and ENT surgery, were concomitant: the odds ratio (OR) of PRAE during non-ENT surgical procedures was 1.43 (95% CI = 0.91-2.24), but increased to 2.74-fold (95% CI = 1.15-4.32) for ENT surgery. The risk of PRAE was significantly lower when the anaesthetic technique included tracheal intubation with relaxants (OR = 0.6, 95% CI = 0.45-0.95) and decreased by 8% with each increasing year of age. CONCLUSIONS: This study demonstrates a high incidence of PRAE in paediatric surgical patients without respiratory tract infections, which appears to be primarily determined by the age of the child and the anaesthetic care rather than by the child's medical history.

Acute hypoxic respiratory failure as the first manifestation of systemic-onset juvenile rheumatoid arthritis in a child.

Systemic onset juvenile rheumatoid arthritis is the most common rheumatologic disorder of childhood. Pleuropulmonary manifestations are rare in children in this multiorgan disease, and are usually not severe. The diagnosis of systemic onset juvenile rheumatoid arthritis is made by exclusion, in the presence of clinical findings constellation. We present the case of an 8-year-old girl who developed acute hypoxic respiratory failure as the first manifestation of systemic onset juvenile rheumatoid arthritis, then severe respiratory relapse 16 months later. Clinical and radiological improvement were achieved at both times after high dose pulse methylprednisolone therapy.