Viral infection and allergy status impact severity of asthma symptoms in children with asthma exacerbations.

BACKGROUND: Although viral infection is known to be associated with asthma exacerbations, prior research has not identified reliable predictors of acute symptom severity in virus-related asthma exacerbations (VRAEs). OBJECTIVE: To determine the effect of asthma control and viral infection on the severity of current illness and evaluate biomarkers related to acute symptoms during asthma exacerbations. METHODS: We prospectively enrolled 120 children with physician-diagnosed asthma and current wheezing who presented to Arkansas Children's Hospital emergency department. The asthma control test (ACT) stratified controlled (ACT > 19) and uncontrolled (ACT ≤ 19) asthma, whereas pediatric respiratory symptom scores evaluated symptoms. Nasopharyngeal swabs were obtained for viral analysis, and inflammatory mediators were evaluated by nasal filter paper and Luminex assays. RESULTS: There were 33 children with controlled asthma and 87 children with uncontrolled asthma. In those with uncontrolled asthma, 77% were infected with viruses during VRAE compared with 58% of those with controlled asthma. Uncontrolled subjects with VRAE had more acute symptoms compared with the controlled subjects with VRAE or uncontrolled subjects without a virus. The uncontrolled subjects with VRAE and allergy had the highest acute symptom scores (3.363 point pediatric respiratory symptom; P = .04). Children with asthma with higher symptom scores had more periostin (P = .02). CONCLUSION: Detection of respiratory viruses is frequent in those with uncontrolled asthma. Uncontrolled subjects with viruses have more acute symptoms during exacerbations, especially in those with allergy. Periostin was highest in subjects with the most acute symptoms, regardless of control status. Taken together, these data imply synergy between viral infection and allergy in subjects with uncontrolled asthma when considering acute asthma symptoms and nasal inflammation during an exacerbation of asthma.

The Spice of Death: Sudden Cardiac Arrest After Novel Psychoactive Substance Exposure.

ABSTRACT: Novel psychoactive substances (NPSs), commonly referred to as "K2" or "spice," are a relatively new toxicology challenge for pediatricians. Adolescents often incorrectly believe that these drugs are safe and can be used without major adverse effects. Although recent legislation attempts to ensure that these drugs are not commercially available, many are able to be purchased online as "not fit for human consumption" or under various misnomers such "incense." In addition, there is a wide chemical variation among these substances, making regulation challenging. Standard urine drug screens test for tetrahydrocannabinol, which may not cross-react with synthetic substances, making NPS poisonings difficult to diagnose. We report a case of fatal cardiac arrest in a 16-year-old adolescent boy temporally associated with use of the NPS, 5F-ADB. The case illustrates the dangerous consequences that these unregulated substances pose to users, as well as the need for the consideration of comprehensive toxicological testing in patients with a history of substance use and sudden cardiac arrest, despite a negative drug screen.

Hemispheric Cerebral Oximetry Monitoring During Pediatric Seizure Activity in a Pediatric Emergency Department.

BACKGROUND: Sustained neuronal activity during seizures causes cellular perturbations, alterations in cerebral physiology, and potentially neurological injury, a neurological emergency. With variable clinical manifestations of seizures, frequent failure of seizure recognition by providers in pediatric and developmentally challenged patients can increase seizure complications. Neuroresuscitation should include rapid cerebral physiology assessment for increased seizure recognition and optimal neurological outcomes. In neurological emergencies, cerebral oximetry has demonstrated its utility in altered cerebral physiology and a standard combat neurological assessment tool. During adult seizures, cerebral oximetry (regional cerebral oxygen saturation [rcSO2]) has been shown as a useful neurological assessment tool, but research is lacking in pediatric emergency department (PED) seizure patients. OBJECTIVE: The aim of this study was to identify trends in rcSO2 readings for patients presenting to the PED with seizure activity and in the postseizure state in order to evaluate usefulness of rcSO2 as a neurological assessment tool in pediatric seizure patients. METHODS: This was a PED observational case series comparing hemispheric rcSO2 readings in first-time clinically evident generalized and focal seizure patients to first-time postseizure patients with no PED seizures. RESULTS: Generalized or focal seizure (n = 185) hemispheric rcSO2 revealed significant differences compared with nonseizure and controls' rcSO2 readings (n = 115) (P < 0.0001). Generalized and focal seizure rcSO2's were either less than 60% or greater than 80% compared with nonseizure rcSO2 (P < 0.0001). Ipsilateral focal seizure rcSO2 correlated to seizure side (P < 0.0001) and was less than the contralateral rcSO2 (P < 0.0001), with interhemispheric rcSO2 discordance greater than 16 (P < 0.0001). Seizure to preseizure rcSO2 discordance was as follows: generalized 15.2, focal: left 19.8, right 20.3 (P < 0.0001). CONCLUSIONS: Hemispheric during-seizure rcSO2 readings significantly correlated with generalized and focal seizures and reflected altered cerebral physiology. Ipsilateral focal seizure rcSO2 readings correlated to the focal side with wide interhemispheric rcSO2 discordance. All postseizure rcSO2 readings returned to preseizure readings, showing altered cerebral physiology resolution. Overall, in generalized or focal seizure, rcSO2 readings were less than 60% or greater than 80%, and in focal seizure, interhemispheric rcSO2 discordance was greater than 10. During seizures, hemispheric rcSO2 readings demonstrated its potential pediatric seizure utility. Utilizing rcSO2 readings related to seizure activity could expedite pediatric and developmentally challenged patients' seizure recognition, cerebral assessment, and interventions especially in pharmacoresistant seizures.

Cerebral oximetry with blood volume index and capnography in intubated and hyperventilated patients.

OBJECTIVE: Hyperventilation-induced hypocapnia leads to cerebral vasoconstriction and hypoperfusion. Intubated patients are often inadvertently hyperventilated during resuscitations, causing theoretical risk for ischemic brain injury. Current emergency department monitoring systems do not detect these changes. The purpose of this study was to determine if cerebral oximetry (rcSo2) with blood volume index (CBVI) would detect hypocapnia-induced cerebral tissue hypoxia and hypoperfusion. METHODS: Patients requiring mechanical ventilation underwent end-tidal CO2 (ETco2), rcSo2, and CBVI monitoring. Baseline data was analyzed and then the effect of varying ETco2 on rcSo2 and CBVI readings was analyzed. Median rcSo2 and CBVI values were compared when above and below the ETco2 30 mmHg threshold. Subgroup analysis and descriptive statistics were also calculated. RESULTS: Thirty-two patients with neurologic emergencies and potential increased intracranial pressure were included. Age ranged from 6 days to 15 years (mean age, 3.1 years; SD, 3.9 years; median age, 1.5 years: 0.46-4.94 years). Diagnoses included bacterial meningitis, viral meningitis, and seizures. ETco2 crossed 30 mm Hg 80 times. Median left and right rcSO2 when ETCO2 was below 30 mmhg was 40.98 (35.3, 45.04) and 39.84 (34.64, 41) respectively. Median left and right CBVI when ETCO2 was below 30 mmhg was -24.86 (-29.92, -19.71) and -22.74 (-27.23, - 13.55) respectively. Median left and right CBVI when ETCO2 was below 30 mmHg was -24.86 (-29.92, -19.71) and -22.74 (-27.23, -13.55) respectively. Median left and right rcSO2 when ETCO2 was above 30 mmHg was 63.53 (61.41, 66.92) and 63.95 (60.23, 67.58) respectively. Median left and right CBVI when ETCO2 was above 30 mmHg was 12.26 (0.97, 20.16) and 8.11 (-0.2, 21.09) respectively. Median duration ETco2 was below 30 mmHg was 17.9 minutes (11.4, 26.59). Each time ETco2 fell below the threshold, there was a significant decrease in rcSo2 and CBVI consistent with decreased cerebral blood flow. While left and right rcSO2 and CBVI decreased quickly once ETCO2​ was below 30 mmHg, increase once ETCO2​ was above 30 mmHg was much slower. CONCLUSION: This preliminary study has demonstrated the ability of rcSo2 with CBVI to noninvasively detect the real-time effects of excessive hyperventilation producing ETco2 < 30 mmHg on cerebral physiology in an emergency department. We have demonstrated in patients with suspected increased intracranial pressure that ETco2 < 30 mmHg causes a significant decrease in cerebral blood flow and regional tissue oxygenation.

Evaluation of Anaphylaxis Management in a Pediatric Emergency Department.

OBJECTIVE: In 2006, the National Institute of Allergy and Infectious Disease established evidence-based treatment guidelines for anaphylaxis. The purpose of our study was to evaluate provider adherence to guidelines-based management for anaphylaxis in a tertiary care pediatric emergency department (ED). METHODS: Retrospective chart review was conducted of patients (0-18 years) presenting to the Arkansas Children Hospital ED from 2004 to 2011 for the treatment of anaphylaxis using International Classification of Diseases, Ninth Edition, codes. Multiple characteristics including demographics, clinical features, allergen source, and anaphylaxis management were collected. Fisher exact or χ tests were used to compare proportion of patients treated with intramuscular (IM) epinephrine in the preguideline versus postguideline period. Relative risk (RR) statistics were computed to estimate the ratio of patients who received self-injectable epinephrine prescription and allergy follow-up in the preguideline and postguideline groups. RESULTS: A total of 187 patients (median [range] age, 7 [1-18] years; 67% male; 48% African American) were evaluated. Food (44%) and hymenoptera stings (22%) were commonly described culprit allergens, whereas 29% had no identifiable allergen. Only 47% (n = 87) received epinephrine in the ED and 31% (n = 27) via the preferred IM route. Comparing postguideline (n = 126) versus preguideline (n = 61) periods demonstrated increase in the usage of the IM route (46% postguideline vs 6% preguideline; risk ratio (RR), 7.64; 95% confidence interval [CI], 2.04-46.0; P < 0.001). Overall, 61% (n = 115) of the patients received self-injectable epinephrine upon discharge, and there were no significant differences between the groups (64% postguideline vs 56% preguideline, P = 0.30). Postguideline patients were more likely to receive a prescription compared with preguideline patients (64% postguideline vs 56% preguideline; RR, 1.15; 95% CI, 0.89-1.55; P = 0.30). Only 45% (n = 85) received an allergy referral. Postguideline patients were more likely to receive an allergy referral than preguideline patients (48% postguideline vs 41% preguideline; RR, 1.16; 95% CI, 0.81-1.73; P = 0.40). CONCLUSIONS: Provider use of IM epinephrine has improved since anaphylaxis guidelines were published. However, more provider education is needed to improve overall adherence of guidelines in a tertiary care pediatric ED.

Validation of the accuracy of a transport ventilator utilizing a pediatric animal model.

OBJECTIVE: The objective of this study was to evaluate 2 transport ventilators utilizing both a test lung and a pediatric animal model. METHODS: Two transport ventilators were utilized for evaluations. A test lung or intubated, sedated pigs (n = 9) with healthy and injured lungs were ventilated using control and support modes. A test lung was used to evaluate alarm responsiveness, FIO2 accuracy, oxygen consumption, and duration of battery power. Pigs were utilized to evaluate the exhalation valve, ventilator response, volume accuracy, and noninvasive functionality. Respiratory mechanics were determined using a forced oscillation technique, and airway flow and pressure waveforms were acquired utilizing a pneumotachograph. RESULTS: For both ventilators, FIO2 accuracy was within 10% error. On an E cylinder of oxygen, the EMV+ operated for 3 hours 48 minutes and the LTV 1200 for 1 hour 4 minutes. On battery power, the LTV 1200 ventilated for 6 hours 51 minutes and the EMV+ for 12 hours 8 minutes. Ventilator response time was less (36%), and delta pressure was greater (38%) for the EMV+ utilizing noninvasive ventilation. The percent error for displayed volume was less than 10% for the EMV+. CONCLUSIONS: In this study, we demonstrate that there are differences between the 2 ventilators in regard to oxygen consumption, duration of battery power, and volume accuracy. Clinicians should be aware of these differences to optimize the choice and use of both ventilators depending on clinical need/setting.

Hfq and three Hfq-dependent small regulatory RNAs-MgrR, RyhB and McaS-coregulate the locus of enterocyte effacement in enteropathogenic Escherichia coli.

Enteropathogenic Escherichia coli (EPEC) is a significant cause of infantile diarrhea and death in developing countries. The pathogenicity island locus of enterocyte effacement (LEE) is essential for EPEC to cause diarrhea. Besides EPEC, the LEE is also present in other gastrointestinal pathogens, most notably enterohemorrhagic E. coli (EHEC). Whereas transcriptional control of the LEE has been meticulously examined, posttranscriptional regulation, including the role of Hfq-dependent small RNAs, remains undercharacterized. However, the past few years have witnessed a surge in the identification of riboregulators of the LEE in EHEC. Contrastingly, the posttranscriptional regulatory landscape of EPEC remains cryptic. Here we demonstrate that the RNA-chaperone Hfq represses the LEE of EPEC by targeting the 5' untranslated leader region of grlR in the grlRA mRNA. Three conserved small regulatory RNAs (sRNAs)-MgrR, RyhB and McaS-are involved in the Hfq-dependent regulation of grlRA MgrR and RyhB exert their effects by directly base-pairing to the 5' region of grlR Whereas MgrR selectively represses grlR but activates grlA, RyhB represses gene expression from the entire grlRA transcript. Meanwhile, McaS appears to target the grlRA mRNA indirectly. Thus, our results provide the first definitive evidence that implicates multiple sRNAs in regulating the LEE and the resulting virulence of EPEC.

Challenges and solutions: pandemic 2009 H1N1 influenza A in a pediatric emergency department.

OBJECTIVE: The purpose of this study was to describe the impact of the 2009 H1N1 influenza pandemic on a pediatric emergency department (ED) at a freestanding children's hospital in the summer and fall of 2009. DESIGN: In July 2009, active prospective surveillance for influenza-like illness (ILI) was performed on a daily basis of patients presenting to the ED of Arkansas Children's Hospital. The Centers for Disease Control and Prevention definition of ILI was used. Records of daily ILI volume were kept. A retrospective review of admissions from the ED to the inpatient service was done for patients with ILI and non-ILI. In addition, comparisons of monthly patient census for the months involved were compared with historical census data. RESULTS: When public schools started in mid-August 2009, there was a rapid and dramatic increase in the number of patients with ILI seen in the pediatric ED. Within 3 weeks, as many as 120 patients with ILI per day were being seen in the ED. The month of September 2009 was the highest census month ever recorded in this ED. The admission rate of the patients with ILI was lower than patients with non-ILI between September and November 2009 (10.8 percent vs 14.8 percent). CONCLUSIONS: The 2009 H1N1 influenza pandemic resulted in unprecedented patient volumes in this pediatric ED; however, patient acuity (based on admission rate) for patients with ILI was lower than patients with non-ILI. Pandemic influenza can overwhelm emergency care resources, even when the overall severity of illness is relatively low.