Eleni Skylogianni

Transcutaneous Bilirubin Nomogram for Prediction of Significant Neonatal Hyperbilirubinemia

OBJECTIVE: The goal was to develop a predictive nomogram, based on transcutaneous bilirubin (TcB) measurements, for assessment of the risk of significant hyperbilirubinemia in healthy term and near-term neonates. METHODS: A total of 10382 TcB measurements were performed with 2039 healthy neonates (gestational age of ≥35 weeks and birth weight of ≥2000 g), with a BiliCheck bilirubinometer (SpectRx, Norcross, GA), at designated time points between 12 and 120 hours of life. According to their severity, these TcB measurements were selectively cross-checked with a direct spectrophotometric device, and significant hyperbilirubinemia was defined on the basis of the hour-specific threshold values for phototherapy proposed by the American Academy of Pediatrics. With the use of likelihood ratios (LRs), the high- and low-risk demarcators for each designated time were calculated and presented on an hour-specific nomogram. RESULTS: Significant hyperbilirubinemia was documented for 122 neonates (6%). At 24 hours of life, the high-risk zone of the nomogram had 73.9% sensitivity and a positive LR of 12.1 in predicting significant hyperbilirubinemia, whereas the low-risk zone had 97.7% sensitivity and a negative LR of 0.04. At 48 hours, the high-risk zone had 90% sensitivity and a positive LR of 12.1, whereas the low-risk zone had 98.8% sensitivity and a negative LR of 0.02. In our study population, the probability of significant hyperbilirubinemia would be >35% for values in the high-risk zone and <0.5% for values in the low-risk zone of the nomogram. CONCLUSIONS: We provide a predictive TcB tool that could allow for a noninvasive, risk-based approach to neonatal hyperbilirubinemia.

Transcutaneous Bilirubin Levels for the First 120 Postnatal Hours in Healthy Neonates

OBJECTIVE: The objective of this study was to provide data on transcutaneous bilirubin (TcB) levels for the first 120 postnatal hours and to develop an hour-specific TcB nomogram for healthy term and near-term neonates. METHODS: From September 2005 to August 2008, we obtained 14864 TcB measurements from 2818 healthy neonates (gestational age ≥ 35 weeks and birth weight ≥ 2000 g). All measurements were performed with the BiliCheck bilirubinometer, at designated times from 12 to 120 postnatal hours. TcB percentiles for each designated time were calculated and used for the development of an hour-specific nomogram. TcB percentiles for neonates who required phototherapy are also presented. RESULTS: The developed TcB nomogram reflects the natural history of TcB levels in healthy neonates up to the fifth postnatal day. A different pattern of TcB increasing rate was noted in neonates who did and did not require phototherapy but with substantial overlap of TcB values between the 2 groups. CONCLUSIONS: We provide data on TcB levels for the first 120 postnatal hours from a large population of white, healthy, term and near-term neonates. We also present a percentile-based TcB nomogram designated for noninvasive and hour-specific evaluation of neonatal hyperbilirubinemia.

Knowledge on Pulse Oximetry Among Pediatric Health Care Professionals: A Multicenter Survey

OBJECTIVES: The objective of this study was to assess the knowledge on pulse oximetry among health care professionals involved in pediatric care. METHODS: A multiple-choice questionnaire was distributed to 505 pediatric health care professionals from 19 hospitals and health centers throughout Greece. Exploratory factor analysis was performed to identify underlying factors that could explain most of the variance of the responses. The mean test and factor scores were calculated and compared between clinical settings. RESULTS: The mean test score was 61.9 ± 18.1%. After factor analysis, 2 distinct groups of deficits in knowledge regarding pulse oximetry were identified: 1 was interpreted as relating to practical knowledge and the other to theoretical knowledge. The mean score of the items that assessed practical knowledge was 82.7 ± 12.5% and of those that assessed theoretical knowledge was 44.2 ± 21.7%. Pediatricians and family practitioners, participants from level 3 institutions, and health care professionals working in ICUs scored better, particularly on the items that assessed theoretical knowledge. Logistic regression analysis revealed that only participants from level 3 institutions and those from ICUs had a greater likelihood of achieving a higher score (total score odds ratio: level 3, 2.89, ICU, 8.13; theoretical knowledge odds ratio: level 3, 3.40, ICU, 10.95). CONCLUSIONS: Pediatric health care professionals have marked deficiencies in their knowledge on pulse oximetry, particularly in regard to the principles underlying the method and its limitations. Strategies that are directed at improving knowledge on pulse oximetry are urgently needed at all levels of experience in pediatric care.

The Forced Oscillation Technique in Paediatric Respiratory Practice.

The Forced Oscillation Technique (FOT) is a lung function modality based on the application of an external oscillatory signal in order to determine the mechanical response of the respiratory system. The method is in principal noninvasive and requires minimal patient cooperation, which makes it suitable for use in young paediatric patients. The FOT has been successfully applied in various paediatric respiratory disorders, such as asthma, cystic fibrosis, and chronic lung disease of prematurity, in order to assess airway obstruction, bronchodilator response, and airway responsiveness after bronchoprovocation challenge. This technique may be more sensitive than spirometry in identifying disturbances of peripheral airways and assessing the level of asthma control or the effectiveness of therapy at the long term. Further research is required to determine the exact role of the FOT in paediatric lung function testing and to incorporate the method in specific diagnostic and management algorithms.

Trends of Transcutaneous Bilirubin in Neonates Who Develop Significant Hyperbilirubinemia

OBJECTIVES: To provide data on the natural course of transcutaneous bilirubin (TcB) levels in neonates before the development of significant hyperbilirubinemia, and to assess the effect of different demographic and perinatal factors on the rate of TcB increase. METHODS: We analyzed 2454 TcB measurements from 419 neonates before the development of significant hyperbilirubinemia. Mean TcB values and TcB percentiles for designated times were calculated, and the effect of different risk factors on the rate of TcB increase was assessed. TcB percentile curves were plotted for comparison on a population-based TcB nomogram. RESULTS: Blood incompatibilities and glucose-6-phosphate dehy-drogenase deficiency were associated with higher rates of TcB in-crease during the first 36 to 48 postnatal hours, whereas smaller gestational age, increased weight loss, and exclusive breastfeeding had a similar but later effect. Compared with general population norms, a different pattern of TcB increase was noted in neonates who developed significant hyperbilirubinemia, but with a sub-stantial overlap of TcB values during the first 24 to 48 postnatal hours. CONCLUSIONS: We provide data on the natural course of TcB levels before the development of significant hyperbilirubinemia in a white population of term and near-term neonates. Smaller gestational age, blood incompatibilities, glucose-6-phosphate dehydrogenase deficiency, increased weight loss, and exclusive breastfeeding significantly affected the rate of TcB increase in a time-dependent manner. These findings may assist in assessing the risk for significant hyperbilirubinemia and planning appropriate follow-up strategies for neonates with borderline bilirubin levels.

Small-airway dysfunction precedes the development of asthma in children with allergic rhinitis

BACKGROUND Epidemiological evidence suggests the existence of a direct link between allergic rhinitis (AR) and asthma. Several studies also support the presence of small-airway dysfunction (SAD) in non-asthmatic children with AR. However, it remains unknown whether SAD can predict the progression of AR to asthma. Our objective was to explore the existence of SAD in non-asthmatic children with AR and to assessed its ability to predict the development of asthma. METHODS Seventy-three 6-year-old children with intermittent moderate-severe AR but without asthma symptoms/medication within the last two years, underwent spirometry and measurement of respiratory resistance (Rrs) and reactance (Xrs) before and after bronchodilation (BD) (300mcg salbutamol). Lung function measurements were performed in the absence of nasal symptoms and repeated at AR exacerbation. SAD was defined as >30% decrease in Rrs or >50% increase in Xrs at 6 or 8Hz post-BD. Participants were followed for five years. RESULTS Twenty-three children (31.5%) developed asthma; this group presented significant post-BD changes in Rrs and Xrs, but only at AR exacerbation. The ability of these changes to predict the development of asthma was exceptional and superior to that of the spirometric parameters. SAD (22 children, 30.1%), emerged as the single most efficient predictor of asthma, independently of other risk factors such as parental asthma, personal history of eczema and type of allergic sensitisation. CONCLUSION SAD precedes the development of asthma in children with AR. Changes in respiratory impedance at AR exacerbation may assist in identifying those at risk to progress to asthma.

Prolonged bronchodilator responsiveness after preschool virus-induced wheezing episodes may predict asthma persistence

Background: Virus-induced wheeze in preschoolers is characterized by reversible airflow limitation which persists several days after the remission of the symptoms. Aims and objectives: To explore whether prolonged bronchodilator responsiveness (BDR) after virus-induced wheezing episodes can predict persistence of asthma at school age. Methods: Seventy two 4-5 years old children with recurrent wheeze (≥3 episodes/year) were included. After a 2-month withdrawal from any respiratory medication, baseline spirometry and measurements of respiratory resistance (Rrs) and reactance (Xrs) (6, 8, 10 Hz) (forced oscillation technique - FOT) before and after bronchodilation were performed. The same measurements were repeated 14 days after the first episode of virus-induced wheeze. BHR was defined for spirometry as FEV0.75 or FEV1 change >15%, while for FOT as Rrs change ≥30% or Xrs change ≥35%. All children were followed until the age of seven. Results: 21 children (29.2%) had asthma at 7 years. At preschool age, both baseline spirometric and FOT BDR was noted in 19% of children with asthma and in 2% of those without (P=0.023). Post-viral episode spirometric BDR was noted in 47.6% of asthmatics and in 3.9% of non asthmatics (P<0.001), whereas post-viral episode FOT BDR in 90.5% of children with asthma and in 7.8% of those without (P<0.001). The area under the ROC curve for spirometric BDR was 0.72 (0.57-0.87) while for FOT BDR 0.91 (0.83-1.00). Conclusions: Prolonged BDR after episodes of virus-induced wheeze at preschool age may predict persistence of asthma at school age. FOT appears to perform better in assessing post-viral wheeze BDR in preschool children.