Papers by Carol Blaisdell
Clinical pathways for asthma are tools that have the potential to improve compliance with nationa... more Clinical pathways for asthma are tools that have the potential to improve compliance with nationally recognized management guidelines, but their effect on patient outcomes has not been documented. To determine the effect of an asthma clinical pathway on patients' length of stay, use of nebulized beta-agonist therapy while hospitalized, and use of acute care clinics for 2 weeks after discharge. The study was a randomized, controlled trial. Patients between the ages of 2 and 18 years admitted with an asthma exacerbation and not under the care of an asthma specialist were eligible for the study. Patients were randomized either to a conventional ward (control group) or to a ward using the clinical pathway (intervention group). For 2 weeks after discharge, we collected data to determine whether patients visited a health care provider for worsening asthma. One hundred ten patients (26%) were enrolled. Control and intervention groups had similar demographic and asthma severity profiles. The intervention group had an average length of stay 13 hours shorter than did the control group. In addition, at every dosing interval, the intervention group received less nebulized beta-agonist therapy. There were no deaths in either group. A clinical pathway for inpatient asthma decreased the length of stay and beta-agonist medication use with no adverse outcomes or increased acute-care encounters through 2 weeks after discharge.
Clinical pathways for asthma are tools that have the potential to improve compliance with nationa... more Clinical pathways for asthma are tools that have the potential to improve compliance with nationally recognized management guidelines, but their effect on patient outcomes has not been documented. To determine the effect of an asthma clinical pathway on patients' length of stay, use of nebulized beta-agonist therapy while hospitalized, and use of acute care clinics for 2 weeks after discharge. The study was a randomized, controlled trial. Patients between the ages of 2 and 18 years admitted with an asthma exacerbation and not under the care of an asthma specialist were eligible for the study. Patients were randomized either to a conventional ward (control group) or to a ward using the clinical pathway (intervention group). For 2 weeks after discharge, we collected data to determine whether patients visited a health care provider for worsening asthma. One hundred ten patients (26%) were enrolled. Control and intervention groups had similar demographic and asthma severity profiles. The intervention group had an average length of stay 13 hours shorter than did the control group. In addition, at every dosing interval, the intervention group received less nebulized beta-agonist therapy. There were no deaths in either group. A clinical pathway for inpatient asthma decreased the length of stay and beta-agonist medication use with no adverse outcomes or increased acute-care encounters through 2 weeks after discharge.
British Journal of General Practice
Background: General practitioners (GPs) have a central place in the management of asthma, particu... more Background: General practitioners (GPs) have a central place in the management of asthma, particularly in the context of acute exacerbations. Aim: To evaluate the management of asthma exacerbations by GPs, and to investigate the ability of risk factors for near fatal asthma to predict the severity of asthma attacks in the community. Design of study: A 1-month multicentre cross-sectional survey. Setting: One thousand and ninety-four GPs of the French Sentinel Network were contacted; 365 responded. Method: Asthma exacerbations were classified according to severity at presentation. Univariate and multivariate analyses were performed by logistic regression to identify those factors associated with severe exacerbations. Results: Exacerbations were described in 219 patients with asthma. Over half (54%) of exacerbations were severe. Peak expiratory flow was recorded during the consultation in 55% of patients who were more than 5 years old. β 2 agonists were prescribed to 93% of patients, systemic corticosteroids to 71%, and antibiotics to 64%. Only 42% of patients had a written action plan for self-management of exacerbations. Risk factors for near fatal asthma, identified in 26% of patients, were not significantly associated with severe asthma exacerbations. Short duration of exacerbation before consultation (<3 hours) was associated with an increase in relative risk of severe exacerbation of 3.38, 95% confidence intervals (CIs) = 1.19 to 9.61, compared with duration of >3 hours. Conclusion: Risk factors for near fatal asthma identified in previous studies were not predictive of a severe exacerbation in general practice, with the exception of short duration of exacerbation before consultation. This suggests that new methods to predict risk in the outpatient settings should be developed.
American journal of respiratory cell and molecular biology, 2014
BMC medical genetics, Jan 26, 2004
Cystic fibrosis (CF) lung disease manifest by impaired chloride secretion leads to eventual respi... more Cystic fibrosis (CF) lung disease manifest by impaired chloride secretion leads to eventual respiratory failure. Candidate genes that may modify CF lung disease severity include alternative chloride channels. The objectives of this study are to identify single nucleotide polymorphisms (SNPs) in the airway epithelial chloride channel, CLC-2, and correlate these polymorphisms with CF lung disease. The CLC-2 promoter, intron 1 and exon 20 were examined for SNPs in adult CF dF508/dF508 homozygotes with mild and severe lung disease (forced expiratory volume at one second (FEV1) > 70% and < 40%). PCR amplification of genomic CLC-2 and sequence analysis revealed 1 polymorphism in the hClC -2 promoter, 4 in intron 1, and none in exon 20. Fisher's analysis within this data set, did not demonstrate a significant relationship between the severity of lung disease and SNPs in the CLC-2 gene. CLC-2 is not a key modifier gene of CF lung phenotype. Further studies evaluating other phenoty...
Proceedings of the American Thoracic Society, 2009
Pediatrics, 2002
To characterize risks to infants and young children from drugs and biological products that were ... more To characterize risks to infants and young children from drugs and biological products that were identified in spontaneous adverse event reports submitted to the US Food and Drug Administration. Of >500 000 MedWatch adverse event reports received by the Food and Drug Administration from November 1997 through December 2000, we identified 7111 reports about infants and children younger than age 2. The reports were analyzed for health outcome (eg, death, hospitalization, congenital anomaly), principal suspect drug, and whether the route of drug exposure was direct administration or through the mother in the perinatal period. Drug therapy was associated with an average of 243 reported deaths annually over the 38-month study period, with 100 (41%) occurring during the first month of life and 204 (84%) during the first year. In 1432 (24%) reported adverse event cases of all levels of severity, exposure to the drug was from the mother during pregnancy, delivery, or lactation. Although 1...
International Journal of Adolescent Medicine and Health, 2010
To investigate the association between sleep disordered breathing (SDB) and parent report of atte... more To investigate the association between sleep disordered breathing (SDB) and parent report of attention and behavioral problems in children, as well as the association between sleep stage duration and measures of child functioning in a clinically referred sample. A chart review was conducted of 95 children with clinical history of SDB who completed an overnight polysomnography study in a pediatric sleep laboratory. Child functioning was assessed at the time of the sleep study by parent report on the Child Behavior Checklist (CBCL). The apnea hypopnea index was used as a measure of SDB severity. The apnea hypopnea index was associated with externalizing behavior, but not attention problems on the CBCL. In children 2-3 years old, stage 4 sleep duration was associated with externalizing behavior. In children 4-16 years old, REM sleep duration was associated with externalizing behavior. Children with increased SDB severity may be at greater risk for behavioral problems. Differences between the association of sleep stages and externalizing behavior in toddlers compared with older children suggests possible developmental differences in the association between sleep and behavior.
Stem Cells, 2009
Because the lung stem cell field is so new, there remain many unanswered questions that are being... more Because the lung stem cell field is so new, there remain many unanswered questions that are being addressed regarding the identification, location, and role of exogenous and endogenous stem and progenitor cell populations in growth, regeneration, and repair of the lung. Advancing lung stem cell biology will require multidisciplinary teams and a long term effort to unravel the biologic processes of stem cells in the lung. While no clinical research in lung stem cell therapies are currently funded by NHLBI, the knowledge gained by understanding the basic biology of the lung stem cell populations will be needed to translate to diagnostic and therapeutic strategies in the future.
Sleep and Breathing, 2008
Asthma has been identified as a possible risk factor for Obstructive Sleep Apnea (OSA) in childre... more Asthma has been identified as a possible risk factor for Obstructive Sleep Apnea (OSA) in children. It is not known whether parent-reported asthma increases the likelihood of the diagnosis of OSA in snoring children. We hypothesized that snoring children with asthma are more likely to have OSA than snoring children without asthma. This study is a 1-year retrospective review of polysomnogram and questionnaire data collected on 236 patients referred to the University of Maryland Pediatric Sleep laboratory for evaluation of snoring. Of the 236 patients, 58% (137/236) were boys, and 79% (173/219 reporting race) were African-American (AA). The age at referral was 7.2±3.7 years (mean±S.D.). Mean body mass index (BMI) percentile was 73.4±32.3%, with 43.2% (54/125) >95th percentile. A history of asthma was reported by 31.4% (74/ 236); no subject was symptomatic on the night of the study. We found no increased risk for polysomnographically diagnosed OSA for asthmatics. To the contrary, by logistic regression analysis, a parent/guardian report of asthma decreased the odds of having OSA by 34% (p=0.027), controlling for individual and socioeconomic factors and assessment results. Polysomnographic (PSG) differences between asthmatic and non-asthmatic children were found in only the arousal index (11.0 vs.9.3±6.5/h, p=0.099) and total sleep time (337.1± 64.3 vs. 347±65.2 min, p=0.1) In a referral-based group of predominantly AA inner-city snoring children, asymptomatic asthma decreased the likelihood of OSA.
Proceedings of the National Academy of Sciences, 1998
Cystic fibrosis (CF) is a lethal inherited disease that results from abnormal chloride conduction... more Cystic fibrosis (CF) is a lethal inherited disease that results from abnormal chloride conduction in epithelial tissues. ClC-2 chloride channels are expressed in epithelia affected by CF and may provide a key ''alternative'' target for pharmacotherapy of this disease. To explore this possibility, the expression level of ClC-2 channels was genetically manipulated in airway epithelial cells derived from a cystic fibrosis patient (IB3-1).
Pediatric Pulmonology, 2006
Nasal potential difference (NPD) has served as a non-invasive diagnostic method for cystic fibros... more Nasal potential difference (NPD) has served as a non-invasive diagnostic method for cystic fibrosis (CF) a disease of chloride channel expression and function in secretory epithelia. Investigators have also used NPD to demonstrate ion transport abnormalities in newborns with respiratory distress. Standard perfusates for diagnostic NPD studies include the use of amiloride, replacement of chloride with gluconate, cAMP agonists, and nucleotides such as ATP. The pH of these perfusates may also be relevant to NPD studies as we have previously shown that the respiratory epithelia in mammals express CLC-2, which is a pH sensitive chloride channel. We hypothesized that acidic pH might activate chloride secretion in vivo if CLC-2 is present in human respiratory epithelia. Our objective was to determine the effect of acidic pH on NPD measurements and the frequency of expression of CLC-2 in normal subjects. Healthy adults were recruited and CLC-2 protein expression was detected in 20 of 29 primary nasal epithelial cell cultures. Acidic pH stimulated NPD responses in 33% of subjects. These findings suggest that pH sensitive alternative pathways are available for modulation in human respiratory epithelia and that NPD protocols should standardize pH of perfusates.
Neural Computing & Applications, 2003
ABSTRACT
Lung, 2009
The pulmonary physician-scientist has a special niche to generate basic research findings and app... more The pulmonary physician-scientist has a special niche to generate basic research findings and apply them to a clinical disease and perhaps impact its medical care. The availability of new high throughput-based scientific technologies in the ''omics era'' has made this an opportune time for physician scientists to prepare and embark on an academic career in respiratory disease research. However, maintaining an adequate flow through the research pipeline of physician-scientist investigators studying respiratory system diseases is currently a challenge. There may not be a sufficient workforce emerging to capitalize on current research opportunities. The National Heart, Lung, and Blood Institute (NHLBI) organized a workshop to assess ways to attract and properly train advanced fellows to pursue research careers in adult and pediatric lung diseases. Participants included representatives from the various pulmonary training programs, respiratory-related professional societies, and NHLBI staff. Deliberation centered on present barriers that might affect interest in pursuing research training, devising better incentives to attract more trainees, and how current research support offered by the NHLBI and the Professional Societies (in partnership with Industry and Patient Support groups) might be better coordinated and optimized to ensure a continued pipeline of pulmonary investigators. Major recommendations offered are: (1) Attract trainees to pulmonary/critical care medicine-based research careers by increasing research exposure and opportunities for high school, college, and medical students. (2) Increase awareness of the outstanding physician-scientist role models in the lung community for trainees. (3) Facilitate mechanisms by which the lung community (NHLBI, professional societies, and partners) can better support and bridge senior fellows as they transition from Institutional Training Grants (T32) to Career Series (K) awards in their early faculty career development.
Lung, 2009
The pulmonary physician-scientist has a special niche to generate basic research findings and app... more The pulmonary physician-scientist has a special niche to generate basic research findings and apply them to a clinical disease and perhaps impact its medical care. The availability of new high throughput-based scientific technologies in the ''omics era'' has made this an opportune time for physician scientists to prepare and embark on an academic career in respiratory disease research. However, maintaining an adequate flow through the research pipeline of physician-scientist investigators studying respiratory system diseases is currently a challenge. There may not be a sufficient workforce emerging to capitalize on current research opportunities. The National Heart, Lung, and Blood Institute (NHLBI) organized a workshop to assess ways to attract and properly train advanced fellows to pursue research careers in adult and pediatric lung diseases. Participants included representatives from the various pulmonary training programs, respiratory-related professional societies, and NHLBI staff. Deliberation centered on present barriers that might affect interest in pursuing research training, devising better incentives to attract more trainees, and how current research support offered by the NHLBI and the Professional Societies (in partnership with Industry and Patient Support groups) might be better coordinated and optimized to ensure a continued pipeline of pulmonary investigators. Major recommendations offered are: (1) Attract trainees to pulmonary/critical care medicine-based research careers by increasing research exposure and opportunities for high school, college, and medical students. (2) Increase awareness of the outstanding physician-scientist role models in the lung community for trainees. (3) Facilitate mechanisms by which the lung community (NHLBI, professional societies, and partners) can better support and bridge senior fellows as they transition from Institutional Training Grants (T32) to Career Series (K) awards in their early faculty career development.
Journal of Asthma, 2006
Asthma causes pediatric morbidity throughout the US with substantial regional variability. Emerge... more Asthma causes pediatric morbidity throughout the US with substantial regional variability. Emergency department (ED) utilization data were studied to determine if geographic variability of pediatric asthma cases exists within a state. Records for non-neonatal Maryland children less than 18 years of age seen and discharged from Maryland EDs from April 1997 through March 2001 were analyzed. While Baltimore City had the highest rates of asthma visits, adjusted odds ratios identified the wealthiest suburban county to have a higher risk of an asthma ED visit. Children from rural counties, for the most part, had fewer ED asthma visits than children from urban and suburban counties.
Journal of Asthma, 2007
Purpose. To evaluate the impact of transition to managed care from fee for service on asthma serv... more Purpose. To evaluate the impact of transition to managed care from fee for service on asthma service utilization among Maryland Medicaid insured children. Methods. Healthcare claims from 1997-2000 for children with asthma insured by Maryland Medicaid were extracted and analyzed. Results. Between 1997-2000, inhaled corticosteroid use increased as a proportion of all asthma medications. Outpatient asthma visits increased from 4.2% to 5.9% of all outpatient claims as both asthma-related hospitalizations and emergency department visits decreased. Conclusions. Restructuring of Maryland Medicaid for children from fee for service to managed care was associated with improvement in asthma-related healthcare utilization claims.
Journal of Asthma, 2002
Asthma hospitalization rates have increased in the United States since 1980. The exposure risk of... more Asthma hospitalization rates have increased in the United States since 1980. The exposure risk of many environmental factors, which contribute to respiratory disease, vary throughout the year. The objective of this study was to investigate the seasonal variation of pediatric asthma hospitalizations and predict hospitalization frequency. This was a longitudinal analysis of all pediatric asthma hospitalizations in the state of Maryland by age, gender, race, and residence using non-confidential discharge data sets from 1986 to 1999. Of the 631,422 pediatric hospitalizations in the state of Maryland during the years 1986-1999, 45,924 (7%) had a primary admission diagnosis of asthma. Frequency of hospitalization for asthma was lowest in the summer in all age groups, and highest in the fall. Seasonal variation in severe asthma episodes was least striking in children aged 15-18. This was in contrast to non-asthma admissions, which were highest in winter in preschool children, but relatively flat in school- and teenaged children. Using neural network modeling, weekly asthma hospitalizations could be predicted with an R2 between 0.71 and 0.8. Temporal trends in asthma hospitalizations were seen in each age group, gender, race, and location. The seasonal variability in asthma hospitalizations suggests that acute asthma is influenced by variables beyond socioeconomic factors and adherence to medical regimens. Strategies to combat exacerbations of asthma should take into consideration seasonal effects on a population. In addition, temporal trends examined over many years can be used to predict frequency of severe asthma episodes in a population.
Journal of Allergy and Clinical Immunology, 2012
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Papers by Carol Blaisdell