bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy, results, and complications of mechanical ventilation in children with status asthmaticus
Authors: Cox Robin G. , Barker Geoffrey A. , Bohn Desmond J. 
Published: March 2007

AbstractWe have conducted a retrospective survey of 79 children out of a total hospital asthmatic patient population of 2,412, admitted over a 32 month period to the ICU for the management of severe status asthmaticus. All patients were in severe respiratory distress with CO2 retention; 19 required mechanical ventilation due to increasing fatigue and worsening bronchospasm, having failed to respond to either inhaled or IV bronchodilator therapy. All patients were ventilated at slow rates (< 12 min) and their airway pressure (Paw) was deliberately kept below 45 cmH2O, while accepting a Pa in the 45–60 mmHg range, as long as the pH was compensated. Although two patients developed pneumothoraces while on positive pressure ventilation, these were resolved without incidents. Five patients who had mediastinal or subcutaneous air leaks prior to intubation did not develop pneumothoraces. Following the initiation of mechanical ventilation, IV β‐agonist therapy was increased in order to reverse the bronchospasm and reduce the duration of mechanical ventilation. Mean duration of intubation was 42 hours. Fourteen of the 19 patients were weaned and extubated within 48 hours. All patients survived without sequelae. We conclude that a degree of controlled “hypoventilation” by deliberately choosing Paw < 45 cmH2O can be successfully used to ventilate children with severe status asthmaticus with a reduced rate of pressure‐related complications.
Asthma in the vicinity of power stations: II. Outdoor air quality and symptoms
Authors: Henry Richard L. , Bridgman Howard A. , Wlodarczyk John , Abramson Rachel , Adler Julie A. , Hensley Michael J. 
Published: March 2007

AbstractTo assess longitudinally the effect of living in the vicinity of coal‐fired power stations on children with asthma, 99 schoolchildren with a history of wheezing in the previous 12 months were studied for 1 year, using daily diaries and measurements of air quality. The children had been identified in a cross‐sectional survey of two coastal areas: Lake Munmorah (LM), within 5 km of two power stations, and Nelson Bay (NB), free from major industry. Daily air quality [sulphur dioxide (SO2) and nitrogen oxides (NOx)], respiratory symptoms, and treatment for asthma were recorded throughout the year.Measurements of SO2 and NOx at LM were well within recommended guidelines although they were several times higher than at NB: maximum daily levels in SO2 (μg/m3) were 26 at LM, 11 at NB (standard, 365); yearly average SO2 was 2 at LM, 0.3 at NB (standard, 60); yearly average NOx (μg/m3) was 2 at LM, 0.4 at NB (standard, 94). Marked weekly fluctuations occured in the prevalence of cough, wheezing, and breathlessness, without any substantial differences between LM and NB. Overall, the prevalence of symptoms was low (10% for wheezing, 20% for any symptom).Whether the daily SO2 and NOx levels affected the occurrence of respiratory symptoms was investigated in children at LM using a logistic regression (Korn and Whittemore technique). For these children as a group, air quality measurements were not associated with the occurrence of symptoms.
Retrosternal density: Pulmonary underdevelopment or accessory hemidiaphragm
Authors: Eid Nemr S. , Shearer Loretta T. , Gultekin Ebru K. 
Published: March 2007

AbstractVertical retrosternal density paralleling the sternum, with haziness of a hemithorax on chest roentgenogram, often challenges the clinical acumen of pediatricians, chest physicians, and pediatric radiologists alike. Its presence has been historically linked to either pulmonary underdevelopment and/or accessory hemidiaphragm. The surgical and radiological pediatric literature has long debated this topic, but unfortunately, it has not received much attention in the general pediatric or in pediatric pulmonology literature. The similar radiologic appearance of these two entities can cause confusion both in diagnostic and therapeutic approach. Many authors advocate an invasive modality, including thoracotomy, as the only definitive way to differentiate between them. We present two similar cases with retrosternal densities, review the pertinent literature, and propose a rational approach to diagnosis and treatment.
Comparison of six ECMO selection criteria and analysis of factors influencing their accuracy
Authors: Payne Nathaniel R. , Kriesmer Pamela , Mammel Mark , Meyer Christopher L. 
Published: March 2007

AbstractThis study compared six extracorporeal membrane oxygenation (ECMO) selection criteria in 42 neonates and analyzed factors influencing the accuracy of outcome predictions. The sensitivity of the criteria in identifying fatal cases varied from 0.44 to 0.94 and the specificity of predictions of survival ranged from 0.42 to 0.69. The criterion having the highest sensitivity had the lowest specificity and conversely the criterion with the lowest sensitivity had the highest specificity. Overall accuracy of the criteria, as measured by the total number of correct outcome predictions, differed little among the criteria (23/42 to 27/42 correct predictions). Three factors influenced predictive accuracy: 1) a primary diagnosis of congenital diaphragmatic hernia (CDH) was associated with a greater mortality (P < 0.001) and a significantly higher positive predictive value (PPV) for all criteria (P = 0.0009–0.012) than that seen in patients with other primary diagnoses; 2) calculating the alveolar‐arterial oxygen gradient using an assumed, rather than measured barometric pressure, or estimating oxygenation index using a calculated, rather than a measured, mean airway pressure, increased false positive mortality predictions in non‐CDH patients; and 3) requiring a peak inspiratory pressure (PIP) of at least 50 cm H2O in the definition of maximal medical management, rather than a PIP of 20–49 cm H2O, significantly increased the PPV for three of four criteria examined (P = 0.02–0.04). Awareness of these factors may facilitate the identification of neonates who need ECMO to survive.
Medical and social factors as predictors of outcome in infant tracheostomy
Authors: Singer Lynn T. , Hill Betsy P. , Orlowski James P. , Doershuk Carl F. 
Published: March 2007

AbstractWe examined the relative impact of infant tracheostomy in comparison to associated medical and social factors, on developmental outcome as part of a cross‐sectional follow‐up of 32 children. These children had no mental retardation, physical handicap, or severe neurological problems, but had a history of long‐term tracheostomy in infancy, ranging from 3 to 146 months duration.Medical factors evaluated included prematurity, neurological status, severity of illness, and number of weeks hospitalized. Social factors included parental education and occupation. Outcome measures included IQ, language quotient, growth parameters, and behavioral competence. Correlation analyses, stepwise multiple regression analyses, and t‐tests were used.Early medical illnesses were significant predictors of cognitive, language, and growth outcome. Severity of medical complications at birth and the presence of any neurological problem predicted 49% of the variance in IQ at follow‐up. Social class was the only variable to predict behavioral outcome, accounting for 28% of the variance. For children without confounding medical conditions, tracheostomy had a negative impact on overall language and auditory comprehension. Once children with confounding medical risk factors were removed from the sample, children with history of infant tracheostomy exhibited significantly lower overall mean lanugage scores (106 versus 120), and lower mean language comprehension scores (104 versus 119) than a matched comparison group.
Pilot study for the development of a monitoring device for ventilated children
Authors: Wensley D. F. , Noonan P. , Seear M. D. , Werner H. , Pirie G. E. 
Published: March 2007

AbstractAirway pressure and air flow were measured at the endotracheal tube in 13 children on a variety of ventilators. These signals were stored for analysis on a computer. Further data sets were obtained after 24 hours or following major interventions. Air flow rate was integrated to give volume. Pulmonary resistance and elastance were obtained by multiple linear regression. Pressure‐volume, pressure‐flow and flow‐volume loops were plotted. “Closed” pressure‐volume and pressure‐flow loops (by subtraction of the resistive or elastic pressure components, respectively) were also displayed, giving compliance and resistance loops. The loops from the initial data set were taken as the baseline, and loops from later data sets were superimposed to provide visual comparisons. Change in clinical status was reflected by the change in slope of compliance and resistance loops. A 30% change in compliance or resistance was easily observed. There was minimal interference with patient care.This pilot study demonstrates that changes in respiratory mechanics can be displayed safely and easily in ventilated patients using resistance and compliance loops. Further work is necessary to confirm the usefulness of real time of these displays.
Prevention of chronic pulmonary oxygen toxicity in young rats with liposome‐encapsulated catalase administered intratracheally
Authors: Thibeault D. W. , Rezaiekhaligh M. , Mabry S. , Beringer T. 
Published: March 2007

AbstractThe lungs and hearts of young rats exposed to 100% oxygen (O2) for 8 days (27 to 35 days of age) were studied following recovery in room air at 60 days of age using morphometric, biochemical, and physiological techniques. In an attempt to prevent chronic oxygen toxicity 153 rats had transtracheal catheters surgically implanted and were treated during the O2 exposure with daily intratracheal injections of liposome‐encapsulated superoxide dismutase (SOD) and/or catalase (CAT). Oxygen exposure in this model results in chronic cardiopulmonary alterations which include pulmonary hypertension, right ventricular hypertrophy, and a decrease in number of pulmonary arterioles 25 to 50 μm in diameter with increased muscularization of their walls. The volume densities of the parenchyma, parenchymal air space, and the alveolar space are increased, while that of the combined alveolar ductal and respiratory bronchiolar space is decreased. Daily intratracheal administration of liposome‐encapsulated CAT (160 U) during the O2 exposure prevented these chronic changes. Liposome‐encapsulated SOD (110 U) or SOD (50 U) + CAT (70 U) did not appear to have a preventive effect. During the first 3 to 5 days following oxygen exposure the lung tissue enzymes SOD, CAT, and glutathione peroxidase markedly increased. We conclude that in the young rat animal model liposomeencapsulated CAT (160 U) given intratracheally during the period of O2 exposure is safe and will prevent the chronic vascular and parenchymal damage due to oxygen toxicity.
The effects of diuresis and transfusion on pulmonary function in children with thalassemia major
Authors: Lands L. C. , Woods S. , Katsardis Ch. , Desmond K. , Coates A. L. 
Published: March 2007

AbstractPrevious pulmonary function studies in subjects with thalassemia major (TM) who were on regular transfusion programs have demonstrated results ranging from small airway obstruction to a restrictive pattern. Ten subjects with TM were studied pre‐ and postdiuresis, and again 24 hr after transfusion, in order to evaluate the role of possible fluid overload in altering pulmonary function. Subjects underwent spirometry and had lung volume and flow volume curves (MEFVC) measured in a volume displacement plethysmograph while breathing air and a mixture of 80% helium and 20% oxygen (HeO2). Six patients had pulmonary mechanics measured with esophageal balloons in place. Baseline function was normal and no change occurred following diuresis. Following transfusion, the volume of isoflow (VisoV̇) decreased, but other parameters did not change. Subsequent analysis revealed 5 subjects with an initial VisoV̇ > 20 (% FVC) but, paradoxically, less evidence of flow limitation in the small airways than those with a VisoV̇ < 20 (% FVC). Posttransfusion, in those subjects with an initially high VisoV̇, the V tended to fall without a change of MEFVC in HeO2, resulting in a decreased VisoV̇. This was interpreted as evidence of subtle abnormalities in the small airways caused by volume expansion, raising doubts about the value of the VisoV as a measure of small airway disease. As a group, our subjects did not demonstrate any abnormalities in baseline function. Some subjects had mild flow limitation in small airways while others developed comparable levels of flow limitation following the volume expansion associated with transfusion.
The impact of home monitoring and daily diary recording on patient status in cystic fibrosis
Authors: Finkelstein Stanley M. , Wielinski Catherine L. , Kujawa Susan J. , Loewenson Ruth , Warwick Warren J. 
Published: March 2007

AbstractAn experimental home monitoring system for assessing the progress and planning changes in the care of patients with cystic fibrosis (CF) has been implemented at the University of Minnesota Cystic Fibrosis Center. One group of patients and families did daily recording of physical measurements and symptoms, and sent the diary to the data coordinating center weekly for analysis. The remaining patients were not part of the home monitoring program. Twenty‐five patients were randomly selected from the home monitoring group. They were compared to an age‐ and sex‐matched control group not doing home monitoring to ascertain if home self‐measurement and daily diary recording, in the absence of any therapeutic intervention, produced any change in physical or psychological status, pulmonary function, or growth over a 4‐year study period. Subjects ranged in age from 6 to 43 years. Clinical status was measured by the National Institutes of Health cystic fibrosis scoring system. Pulmonary function was assessed as percent of predicted forced vital capacity and percent of predicted forced expiratory volume in 1 sec (FEV1). Growth was analyzed as percent of predicted weight based on age‐, sex‐, and height‐dependent equations. Psychological status was determined by self‐assessment and referral for counseling. Only percent predicted FEV1 in the control group declined significantly. There were no statistically significant changes in any other measures either within or between diary and nondiary groups over the 4‐year period. As the long held concern regarding the negative impact of such close monitoring on patient health was not realized, home monitoring could become a useful methodology for following slowly developing changes in the condition of patients with CF and other chronic diseases.
Rescue ventilation with high frequency oscillation in premature baboons with hyaline membrane disease
Authors: Delemos Robert A. , Coalson Jacqueline J. , Delemos James A. , King Richard J. , Clark Reese H. , Gerstmann Dale R. 
Published: March 2007

AbstractWe tested the hypothesis that high‐frequency oscillatory ventilation can be efficacious in hyaline membrane disease (HMD) even after lung injury is established. We compared high frequency oscillatory ventilation (HFOV) rescue (n = 8; 15 Hz; I:E = 1:2) after 8 hours of positive pressure ventilation (PPV) with positive end‐expiratory pressure, to continued PPV (control, n = 7) in premature baboons with HMD over a 24 hour period. Ventilator settings and physiologic parameters were recorded hourly. At necropsy (24 hours), lung status pressure‐volume curves, alveolar phospholipids (PL), platelet activating factor‐like activity (PAF), and lung water were determined. Roentgenographic and morphologic differences in lung inflation were quantified by standard techniques. No intergroup differences were found in heart rate, blood pressures, ventilator settings, FiO2, blood gases, or chest radiographs during the first 8 hours. Both groups had progressive physiologic disease. At 8 hours, HFOV‐rescue animals, in contrast to controls, had immediate significant time‐related improvements in Pa/AO2 (at the same Paw) and in oxygenation index (Pa/AO2/Paw) lasting for 16 hours. No significant intergroup differences in lung/body weight, lung water, lung mechanics, PL, PAF, or frequency of moderate to severe roentgenographic changes existed at 24 hours. Although all animals had morphologic evidence of HMD, saccular aeration was more uniform and airway dilatation less evident in HFOV rescue (P < 0.0001). Based on the improved gas exchange, we conclude that HFOV rescue was efficacious in the “late” treatment of HMD, presumably because of the more uniform saccular aeration. Though HFOV rescue did not appear to reverse lung injury incurred during the first 8 hours of PPV, it may have interrupted the progression of injury, as seen in the PPV control group.
Effects of passive smoking on lung growth in children
Authors: Lebowitz Michael D. , Sherrill Duane , Holberg Catharine J. 
Published: March 2007

AbstractThe objective of this study was to determine the effects of passive smoking on functional lung growth in children and adolescents. It was hypothesized that passive smoking might reduce lung function growth, especially in susceptible children. The assumption was that those most susceptible would be children who started with low lung function, as it had been shown that they had slower growth of lung function, and start to decline earlier. There were 138 non‐Hispanic Caucasian children and adolescents, ages 5 through 15, who had at least three satisfactory longitudinal lung function tests over a 13 year period in the Tucson epidemiological study of airway obstructive diseases. Those who started in childhood with normal function did not show any effect of passive smoking, nor did females who started with low lung function. Males starting with low lung function whose parents smoked showed definite changes. Their forced expiratory volume in 1 second (FEV1) grew even more slowly between ages 13 through 16, related primarily to continuous parental smoking. They also had higher rates of decline for FEV1to forced vital capacity (FVC) ratio and maximum flow at 50% vital capacity to FVC ratios than either the low function group without passive smoking or the normal function groups. This was independent of any symptoms or diagnoses present in this male low function group.
Continuous subcutaneous infusion of β2‐agonists in infantile asthma
Authors: Brémont F. , Moisan V. , Dutau G. 
Published: March 2007

AbstractEleven infants presenting with an asthmatic syndrome were treated with subcutaneous infusions of a β2‐agonist (β2 A) during an acute episode. This treatment was used after difficulties with or failure of β2 A infusions and IV nebulizations. No local or general adverse reactions were observed. The serum concentrations of salbutamol obtained at a dose of 0.1 μg/kg/min were measured in six infants and found to be within the generally accepted therapeutic range. This mode of administration proved extremely useful, both by itself and as part of a therapeutic protocol, combined with an antibiotic, a corticosteroid, and theophylline. It avoids the difficulties of administering β2 A intravenously or by nebulization, while preserving some degree of freedom and better general care for the child. The preferred indication is in treatment of severe acute asthmatic episodes after failure of nebulizations. The exact place in the therapeutic arsenal of infantile asthma remains to be defined. Pediatr pulmonol.1992; 12:81–83.
Integrated plasma cortisol concentration in children with asthma receiving long‐term inhaled corticosteroids
Authors: Phillip Moshe , Aviram Micha , Leiberman Esther , Zadik Zvi , Giat Yehudit , Levy Josef , Tal Asher 
Published: March 2007

AbstractWe assessed the effect of long‐term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary—adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6–16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 μg/kg (200–450 μg/day) for 6 months to 4 years. The control group included six children (age, 6–16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24‐hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean ± SD, 4.9 ± 3.3 vs 9.1 ± 1.9 μg/mL P < 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP‐treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long‐term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary—adrenal axis.
Nonlinear pressure/volume relationship and measurements of lung mechanics in infants
Authors: Neto Galdino Silva , Gerhardt Tilo , Silberberg Ants , Gerhardt Till , Claure Nelson , Duara Shahnaz , Bancalari Eduardo 
Published: March 2007

AbstractWe examined the effects of within‐breath changes in compliance (C) upon the accuracy of measurements of compliance and resistance (R) by linear regression analysis and by Mead and Wittenberger's method. These effects were illustrated by a computer model and by lung models with linear and nonlinear pressure/volume relationships, and were also studied in 14 normal spontaneously breathing premature infants (mean ± SD, BW 1,290 ± 200 g, GA 29.9 ± 2.7 weeks, age 7.4 ± 2.1 days). Flow was measured by pneumotachography and tidal volume was derived as digitally integrated flow, and transpulmonary pressure as airway minus esophageal pressure.We found that C and R calculated from the equation of motion is accurate only if C and R remain constant throughout the respiratory cycle. Calculated compliance depends more on C at the end than at the beginning of inspiration. A decreasing C leads to underestimation or R, while an increasing C leads to an overestimation of inspiratory R. Calculated total R may be accurate, but with low r values for measurement points. Mead and Wittenberger's method and the regression method are similarly affected by changing C; however, since the regression method is based on many more measurement points and therefore allows the detection and analysis of within‐breath changes of C and R, it is less prone to erroneous results secondary to signal artifacts than Mead and Wittenberger's method.
Transfusion‐induced changes in the breathing pattern of healthy preterm anemic infants
Authors: Sasidharan P. , Heimler R. 
Published: March 2007

AbstractIn order to evaluate the effects of transfusion on breathing pattern in growing, otherwise healthy, anemic preterm infants, we studied 14 infants whose mean ± SD birthweight was 1,212 ± 294 grams, gestational age 29.28 ± 2.23 weeks and hematocrit 25.86 ± 2.24%. At a mean postnatal age of 41.35 ± 19.45 days 12 hour nocturnal (transthoracic impedance) pneumocardiograms were obtained 24 hours prior to and after transfusion with 10 mL/kg of packed red blood cells. Posttransfusion pneumocardiograms revealed significant reduction of periodic breathing, of apnea episodes with 11–15 second duration, of apnea density, and of heart rate. These findings indicate that transfusion with packed red blood cells significantly alters certain cardiorespiratory variables in anemic preterm infants.