bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bronchodilator response during acute viral bronchiolitis in infancy
Authors: Soto Manuel E. , Sly Peter D. , Uren Eric , Taussig Lynn M. , Landau Louis I. 
Published: March 2007

AbstractBronchodilator responsiveness was assessed by measuring specific respiratory conductance before and after inhalation of aerosolized bronchodilator in 50 infants who had acute bronchiolitis due to respiratory syncytial virus infection. Thirty per cent of the infants showed an improvement in specific conductance. Responders could not be differentiated from nonresponders by family histories of atopy, eosinophil counts, or immunoglobulin levels in blood and nasal secretions. Eighty‐three per cent of the families and 54% of the mothers of the infants were smokers. Babies of smoking mothers had lower specific conductances than did those of nonsmoking mothers but showed no differences in bronchodilator response. The clinical significance of this bronchodilator‐responsive subgroup has yet to be defined.
Ultrastructure of the bronchial epithelium in three children with asthma
Authors: Konrádová V. , Čopová C. , Suková B. , Houštěk J. 
Published: March 2007

AbstractThe ultrastructure of the bronchial epithelium of three asthmatic girls was studied from material obtained during bronchoscopy. In all patients the large bronchi were lined with an altered pseudostratified ciliated epithelium having a severely damaged ciliary border. Injury to the ciliated cells was manifested by apical bleb formation, destruction of free kinocilia, pathological ciliogenesis, dilation of the spaces of the endoplasmic reticulum and Golgi complex, an increase in the number of vacuoles and lysosomes, and the appearance of altered mitochondria. The most outstanding feature of the epithelium was the marked hyperplasia of the goblet cells with the development of intraepithelial mucous glands. The mucous elements of the epithelium had discharged their mucus. Further, there were signs of mucus cell injury and degeneration. Squamous metaplasia of the pseudostratified epithelium was not observed.
Breathing pattern of neonates during nonnutritive sucking
Authors: Mathew Oommen P. , Clark Mark L. , Pronske Maria H. 
Published: March 2007

AbstractAlteration of the breathing pattern seen during oral feeding has been attributed to the behavioral activity of sucking, repeated swallowing, and laryngeal chemoreceptor stimulation. Because it preserves the behavioral activity of sucking but eliminates the laryngeal chemoreceptor stimulation and repeated swallowing that occurs during nutritive sucking, the effects of nonnutritive sucking was evaluated in 19 term infants. The suck‐pause pattern seen during nonnutritive sucking is similar to that of nutritive sucking. None of the variables measured (inspiratory duration, expiratory duration, breathing frequency, and tidal volume) were significantly altered during the overall period of nonnutritive sucking when compared with previously obtained control values. These results suggest that the alteration of breathing pattern observed during oral feeding cannot be accounted for by the behavioral activity of sucking per se. However, when the sucking phases of the nonnutritive period were compared with the intervening pauses, a reduction in the expiratory duration (P < 0.05) and a reduction in tidal volume (P < 0.05) were observed. Thus, the breathing pattern of human neonates is indeed altered during the sucking phase of the nonnutritive period; pressure changes associated with sucking may account for this alteration.
Clinical applications of ultrathin flexible bronchoscopes
Authors: Wood Robert E. 
Published: March 2007

AbstractThree different models of ultrathin flexible fiberoptic bronchoscopes (1.8, 2.3, and 2.7 mm in diameter) were used in 190 examinations of pediatric patients. These instruments facilitate clinical procedures and evaluations that are difficult if not impossible with previous bronchoscopes. New applications include endoscopic transnasal intubation with endotracheal tubes as small as 3.0 mm (ID), inspection of the upper lobe segments in infants weighing less than 2.5 kg, and evaluation of the lower airways through endotracheal tubes as small as 2.5 mm (ID) or tracheostomy tubes as small as no. 00 (3.1 mm ID). Although these instruments have no suction channel and are thus incapable of removing airway secretions or obtaining specimens, they are extremely useful for many clinical purposes in infants and young children.
The effects of air pollution on the respiratory health of children: A cross‐sectional study
Authors: Spinaci S. , Arossa W. , Bugiani M. , Natale P. , Bucca C. , de Candussio G. 
Published: March 2007

AbstractTo investigate the effects of air pollution on the respiratory health of children, a subject of some controversy, a comparative study was undertaken of 2,385 school children who lived in central urban, peripheral urban, and suburban areas. Daily monitoring of sulphur dioxide and total suspended particle concentrations in all areas showed that pollutant concentrations in central and peripheral urban areas were above commonly accepted safety levels for respiratory health, while concentrations in the suburban area were within acceptable limits. A questionnaire administered to each mother assessed environmental exposure to pollutants in the household, the occurrence of respiratory symptoms as well as lung diseases as diagnosed by a physician, and general information. Children were interviewed about smoking habits and any acute respiratory symptoms. Children also performed standard lung function tests. Results showed that children from both urban areas had lessened pulmonary function and a higher prevalence of bronchial secretion with common colds than did those from the suburban area. These differences persisted after corrections for exposure to indoor pollutants, active or passive smoking, socieconomic status, and sex. Parental cigarette smoking was related to a fall in forced expiratory volume in 1 second and an increased incidence of acute respiratory illnesses and chronic cough in children. Although boys had higher lung volumes and lower air flow, regression analysis showed no significant influence of the interactions “sexgeographic area” and “sex‐smoking” on lung function. It was concluded that air pollution has a significant effect on the respiratory health of children. (Key words: active and passive smoking; respiratory health of children; sulphur dioxide; total suspended particle conc.;
urban vs suburban air pollution.) Pediatr Pulmonol 1985; 1:262‐266.
Observations on the limitations of two apnea/respiration monitors commonly used in the home
Authors: Macfadyen U. M. , Simpson H. 
Published: March 2007

AbstractThe performance of two types of respiration monitor was studied with regard to detection of central apnea and individual breaths. Each monitor detected central apnea more frequently than routine intermittent nursing observation. Both false alarms, when the monitor failed to detect breathing movements (false positive for apnea), and false respiration signals, when the monitor failed to detect the absence of breathing movements (false negative for apnea) were found. The latter sometimes prevented alarms. It was found that a trial period of monitoring under the controlled conditions described permitted adjustments to be made which eliminated or minimized these sources of error. This should be considered when the monitors are issued for use in the home. It is important that persons issuing the monitors be aware of their limitations.
The delivery of therapeutic aerosols through endotracheal tubes
Authors: Ahrens Richard C. , Ries Rebecca A. , Popendorf William , Wiese James A. 
Published: March 2007

AbstractWe used an in vitro model system to examine the sites of deposition of aqueous therapeutic aerosols administered through 3‐mm, 6‐mm, and 9‐mm endotracheal tubes (commonly used in infants, children, and adults) at clinically relevant inspiratory flow rates. Aerosol was delivered to the endotracheal tube via a “T” piece and a 90° elbow. Aerosol exiting the endotracheal tube passed through an appropriately sized Plexiglas model of the trachea and mainstem bronchi, and then into an 80‐liter bag. Aerosol deposited in the “T” and elbow, endotracheal tube, large airway model, and collection bag was quantitated separately using 0.1% uranine as a tracer. Study of a conventional aerosol typical of those in common clinical use (aerodynamic mass median diameter = 3.95 μm) showed that most of the aerosol delivered into each endotracheal tube was deposited before leaving the mainstem bronchi. Substitution of an alternative nebulizer that produced a much smaller aerosol particle size (aerodynamic mass median diameter = 0.54 μm) dramatically decreased aerosol deposition in the “T” and elbow, endotracheal tube, and large airway model, and increased the quantity of aerosol penetrating beyond the mainstem bronchi up to ninefold. The mass median particle diameter of the conventional aerosol was reduced during endotracheal tube and large airway passage by poorly defined aerodynamic mechanisms that selectively removed larger particles. The smaller submicron aerosol was not similarly affected. Thus, conventional therapeutic aerosols appear to penetrate poorly through endotracheal tubes. Use of smaller particle size aerosols in treatment of intubated patients may be an effective way to circumvent this problem.
Diagnostic implications and treatment of massive spontaneous atelectasis in childhood
Authors: MÜLler Wolfgag , Hardt Horst Von Der , Rieger Christian H. L. 
Published: March 2007

AbstractDuring a 5‐month period five children were treated for spontaneously occurring massive lung atelectasis. In three patients the underlying disease was bronchial asthma; in one patient idiopathic plastic bronchitis; and in another patient, infection with anaerobic Corynebacteria may have been a contributing factor. Types I and III hypersensitivity reactions were not considered to be likely causal factors. The clinical manifestations and management of this relatively rare event are described.
Intralobar pulmonary sequestration (a nonentity?)
Authors: Holder Pamela D. , Lansston Claire 
Published: March 2007

AbstractIntralobar pulmonary sequestration has generally been considered a congenital malformation in which an accessory lung bud develops, is enveloped by normal lung, and retains its systemic arterial supply. Also usually included in the “sequestration spectrum” are aberrant arteries to normal lung with either normal or anomalous venous connection. We reviewed all surgical pathology specimens and autopsies performed at Texas Children's Hospital from 1955 through 1984. There were 15 cases with an aberrant systemic artery to normal or abnormal lung. Nine were cases of structurally normal lung with an aberrant systemic artery, and five were cystic adenomatoid malformations with a systemic artery. In one older child some features of intralobar sequestration were present, but a major bronchial connection was retained. We propose that most intralobar sequestrations represent either cystic adenomatoid malformations that clinically are unrecognized until they become secondarily infected or developmentally normal lung supplied by a systemic artery.
Liposyn infusion increases plasma prostaglandin concentrations
Authors: Hunt Carl E. , Pachman Lauren M. , Hageman Joseph R. , Cobb Michael A. , Klemka Linda 
Published: March 2007

AbstractTo determine whether Liposyn infusion results in increased plasma prosta‐glandin (PG) concentrations, the following study was performed in 33 adult rabbits with chronically implanted arterial and venous catheters. Plasma PG concentrations were determined by radioimmunoassay for two vasodilators, PGE2 and PGI2 (as measured by its metabolite 6‐keto‐PGF1α), and two vasoconstrictors, thromboxane (TX) A2, and PGF2α, as measured by their metabolites TXB2 and PGF2α‐M, respectively. A 1‐hour infusion of Liposyn at 4 ml per kg resulted in statistically significant increases in arterial and venous concentrations of PGE2 and 6‐keto‐PGF1α (p < 0.001) and of TXB, (p < 0.04). There were no significant changes in PGF2α‐M plasma concentrations. Liposyn infustion also resulted in a small but statistically significant increase in Pao2 of 4.7 ± 1.5 torr (p < 0.01). It is concluded that Liposyn infusion results in statistically significant increases in plasma concentrations of PGE2, 6‐keto‐PGF1α, and TXB2.
Management of children hospitalized for laryngotracheobronchitis
Authors: Wagener Jeffrey S. , Landau Louis I. , Olinsky Anthony , Phelan Peter D. 
Published: March 2007

AbstractDuring a 12‐month period, 527 consecutive admissions for laryngotracheobronchitis (LTB) were reviewed to determine the epidemiology of hospitalized LTB patients and to better define patients who may benefit from therapy other than close observation. Viral cultures were obtained in 442 patients and were positive in 70%. Disease severity at the time of admission was unrelated to patient age or sex. Duration of hospitalization, however, was inversely related to age (p < 0.001). Laboratory investigations were rarely abnormal or of therapeutic value. Patients who on admission had stridor without sternal and chest wall retractions recovered rapidly and spontaneously; they were frequently discharged within 48 hours and never required artificial airways. Children who had sternal and chest wall retractions on admission experienced longer hospitalizations, frequently received medical intervention such as aqueous mist therapy or racemic epinephrine, and had a 6% risk of requiring artificial airway support. This group of children should be studied selectively for the benefits of specific medical therapies and diagnostic evaluations.
Alterations in plasma amino acid levels in children with asthma: A preliminary investigation
Authors: Inselman Laura S. , Khan Farida , Evans Hugh E. 
Published: March 2007

AbstractConcentrations of plasma amino acids and cortisol were measured in 27 children with status asthmaticus, moderate, or mild asthma and in 7 controls without lung disease. Individuals with conditions potentially altering amino acid levels were excluded. Measurements were made at 8 A.M. and 4 P.M. on the same day. Of the 24 amino acids analyzed, threonine, serine, citrulline, tyrosine, proline, alanine, cystine, isoleucine, ornithine, lysine, and arginine were decreased at 8 A.M. or 4 P.M. and plasma cortisol was elevated at 4 P.M. in patients with status asthmaticus when compared with the other groups (p < 0.05). Normal diurnal variations of amino acids and cortisol were preserved in all groups. Sequential daily determinations in eight patients with status asthmaticus showed progressive increases in total and many individual amino acids as symptoms subsided. These studies demonstrate a decrease of certain gluconeogenic amino acids in the plasma in status asthmaticus. This diminution could reflect the need for maintenance of normal glucose concentrations in status asthmaticus. The decrease in gluconeogenic amino acid levels may play a role in the severity of asthma.
Airway hyperreactivity and a history of clinical manifestations of asthma in childhood
Authors: Mark John D. , McBride John T. , Brooks John G. , McConnochie Kenneth M. , Hall William J. 
Published: March 2007

AbstractThe relationship between airway hyperreactivity and a history of the clinical manifestations of asthma was investigated in 54 children between the ages of 8 and 12. Airway reactivity was assessed by measuring the change in pulmonary function following the hyperventilation of subfreezing air. Clinical manifestations of asthma were assessed by a standardized questionnaire regarding lower respiratory symptoms and by medical records review. The subjects were participating in a study of the sequelae of bronchiolitis; 25 had seen a physician for mild bronchiolitis during the first 2 years of life, and the remainder had not. Airway hyperreactivity was demonstrated in 8 of the 54 children and correlated with use of medication for asthma in the 2 years before pulmonary testing and positive parental response to the question, “Does your child wheeze apart from colds?” Airway hyperreactivity did not correlate with a history of other respiratory symptoms or with a history of physician‐diagnosed wheezing or asthma. No questionnaire or chart review item identified over 50% of the children with reactive airways, and most subjects identified by each of the items did not demonstrate hyperreactive airways. These data suggest that airway reactivity is only weakly associated with a history of the clinical manifestations of asthma in childhood, in part because children with clinically inactive asthma do not consistently demonstrate airway hyperreactivity and in part because many children with hyperreactive airways have never had respiratory symptoms.
Determinants of the first inspiratory volume and functional residual capacity at birth
Authors: Vyas H. , Field D. , Milner A. D. , Hopkin I. E. 
Published: March 2007

AbstractWe have investigated the pattern of pressure and volume changes that occur in vaginally delivered, full‐term infants during the onset of spontaneous respiration. Within a few seconds of delivery of the head, simultaneous measurements were made of stomach and esophageal pressure changes together with volume changes determined at the mouth. Values obtained for volume were very similar, but pressure changes were of a greater magnitude than previously reported. A significant correlation has been shown between first inspiratory volume and functional residual capacity (FRC) at the end of the first breath (p < 0.004). No significant relationship was found between first inspiratory pressure and FRC. However, using a calculated index of inspiratory pressure and time (“inspiratory effort”), a significant relationship of this to FRC was observed (p < 0.02).
Diaphragmatic pressures in piglets: Transvenous versus direct phrenic nerve stimulation
Authors: Watchko J. F. , Mayock D. E. , Standaert T. A. , Woodrum D. E. 
Published: March 2007

AbstractWe examined transdiaphragmatic pressure (Pdi) generation during both direct (DPNS) and transvenous (TVPNS) modes of phrenic nerve stimulation in anesthetized piglets of varying postnatal age. Pdi measurements during TVPNS were not statistically different from those obtained during DPNS (p > 0.10). Furthermore, a good correlation (r = 0.98, p < 0.001) was obtained when the mean Pdi measurements obtained by both methods were compared. We conclude that TVPNS can be used in lieu of DPNS to generate Pdi. Furthermore, our data suggest that this technique can be used to study the effects of various experimental manipulations on diaphragmatic force output within a developmental context.
Physiologic effects of terbutaline on pulmonary function of infants with bronchopulmonary dysplasia
Authors: Sosulski Richard , Abbasi Soraya , Bhutani Vinod K. , Fox William W. 
Published: March 2007

AbstractThis study defines the physiologic changes in pulmonary mechanics induced by subcutaneous terbutaline administration in ventilator‐dependent infants with severe bronchopulmonary dysplasia (BPD). Eight such infants (mean ± SEM weight = 2.56 ± 0.32kg, postnatal age = 13.0 ± 3.2 weeks) were chosen for the study. Pulmonary mechanics and arterial blood gases were measured in the control state and at 30 and 60 minutes following the subcutaneous injection of 5 μg/kg terbutaline. There was a significant (p < 0.001) improvement in lung compliance from baseline values at 30 minutes and at 60 minutes (38%). A significant (p < 0.05) decrease of 23% in the average pulmonary resistance at 30 minutes and a 26% decrease at 60 minutes from control values were observed. An increase in the I/E ratio occurred in all patients at 60 minutes (p < 0.01). In addition, clinical improvement was noted in six of eight infants. Administration of terbutaline demonstrated a significant improvement in the pulmonary mechanics of infants with severe BPD.
Multiple factors limit exercise capacity in cystic fibrosis
Authors: Marcotte Jacques E. , Grisdale Robert K. , Levison Henry , Canny Gerard J. , Coates Allan L. 
Published: March 2007

AbstractExercise testing was performed in 50 patients with cystic fibrosis to determine whether hemodynamic factors limit exercise capacity in the disease. Prior to exercise testing, lung function and blood gas values were measured. Nutritional status was determined by calculating a weight for height (Wt for Ht) ratio for each subject. A progressive exercise test was used to determine maximum work capacity (Wmax). Cardiac output (Q) (indirect Fick method), and stroke volume (SV) were computed during steady‐state exercise at 50% Wmax in 21 of 50 patients. Wmax, SV, Q, and lung function results are expressed as per cent predicted. The mean (± SD) Wmax was 75 ± 23%. Multiple regression analysis showed that maximum voluntary ventilation, resting Pao2, and Wt for Ht accounted for 84% of the variance in Wmax. Although some patients had a reduced SV (mean = 96%) during steady‐state exercise, all patients achieved a normal cardiac output (mean = 115%). SV correlated with resting Pao, but not with lung function. We conclude that (1) exercise capacity in cystic fibrosis is influenced by lung function, nutritional status, and resting hypoxemia, but not by cardiac function; (2) the SV limitation noted in some patients may be due to increased pulmonary vascular resistance related to hypoxemia.
Single‐dose pharmacokinetics of aztreonam in children with cystic fibrosis
Authors: Reed Michael D. , Aronoff Stephen C. , Stern Robert C. , Yamashita Toyoko S. , Myers Carolyn M. , Friedhoff Lawrence T. , Blumer Jeffrey L. 
Published: March 2007

AbstractThe single‐dose pharmacokinetics of aztreonam was evaluated in 10 clinically stable subjects with cystic fibrosis. Each child received 30 mg aztreonam/kg intravenously over 2 to 3 minutes. Multiple timed blood samples were obtained over 8 hours for determination of aztreonam elimination kinetics; all urine excreted for 24 hours was collected in timed aliquots for the determination of aztreonam and its microbiologically inactive metabolite, SQ 26,992. Aztreonam pharmacokinetic parameters were determined by model‐independent methods. Mean t1/2, steady‐state volume distribution, and body clearance were 1.3 hr, 0.25 L/kg, and 127.2 ml/min/1.73m2, respectively. In 9 of the 10 subjects, two‐compartment pharmacokinetic analysis was possible and compared favorably with model‐independent parameter estimates. Twenty‐four‐hour urinary recovery of aztreonam was 76.3% of the administered dose; 2.6% was recovered as the metabolite SQ 26,992. The renal clearance of aztreonam averaged 92.5 ml/min/1.73m2. When these data are combined with in vitro susceptibility data for aztreonam against Pseudomonas aerusinosa isolated from the sputum of patients with cystic fibrosis, a dose of 200 mg aztreonam/kg/day divided six hourly would be predicted to maintain serum concentrations above the minimum inhibitory concentration (MIC) for these organisms for the majority of the dosing interval.