bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polysomnography in obese children with a history of sleep‐associated breathing disorders
Authors: Silvestri Jean M. , Weese‐Mayer Debra E. , Bass Michelle T. , Kenny Anna S. , Hauptman Susan A. , Pearsall Sheilah M. 
Published: March 2007

AbstractWe hypothesized that obese children with a history of breathing difficulty during sleep would demonstrate (1) evidence of complete and partial obstructive sleep apnea (OSA) with hypercarbia and/or hypoxemia; and (2) correlation between symptoms, degree of obesity, adenoid and tonsil size, and polysomnography (PSG) results. We evaluated 32 obese children [% ideal body weight (IBW), 196±45%] with a sleep history questionnaire, airway radiographs, electrocardiograms (ECG), and PSG. By history, we found snoring (100%), difficulty breathing (59%), sweating (44%). restlessness (53%), arousals (41%), apnea (50%), worsening with upper respiratory infection (URI) (81%), hypersomnolence (59%), and mouth breathing (59%). We found adenoid and/or tonsil enlargement on 75% of airway x‐ray pictures. ECGs were abnormal in 5 patients. Among all patients, mean sleep study oxyhemoglobin saturation (SaO2) was 85±16% and mean end‐tidal CO2 (PetCO2 ) was 51±7 torr; 84% had paradoxical inward movement of the chest on inspiration, 59% had OSA, and 66% had partial OSA. In those with ⩾200% IBW and adenotonsillar enlargement, elevated PetCO2 and the presence of hypoxemia (SaO2<90%) for ⩾5% of the total sleep time (TST) were correlated, unlike in patients of similar weight but without adenotonsillar enlargement. Individual symptoms did not correlate with the severity of PSG abnormalities. By discriminant analysis, using three variables (IBW, presence of adenotonsillar tissue, and presence of ⩾5 symptoms), we could predict PSG abnormalities with up to 81% reliability. Our findings indicate that in obese children, particularly those with %IBW ⩾200 and adenotonsillar hypertrophy, with sleep‐disordered breathing evaluation by polysomnography should be considered. Pediatr Pulmonol. 1993; 16:124–129. © 1993 Wiley‐Liss, Inc.
Effect of obesity on pulmonary function in children
Authors: Inselman Laura S. , Milanese Ann , Deurloo Antoinette 
Published: March 2007

AbstractThe effect of obesity on pulmonary function was studied in 13 children, aged 8‐15 years, with 147‐300% ideal body weight (IBW). Measurements included lung volumes, airflow rates pre‐ and post‐bronchodilator nebulization, diffusing capacity (DLCO), maximal voluntary ventilation (MW), minute ventilation V̇E), and resting energy expenditure (REE). When compared with predicted normal values for sex, height, and body surface area (BSA), decreases (mean % predicted,±SE) were observed in expiratory reserve volume (ERV, 36±5); forced expiratory volume in 1 second (FEV1, 73±5); forced expiratory flow between 25% and 75% of vital capacity (FEF25‐75% 70±6); DLCO, absolute (52±3) and corrected (DLCO/VA, 71±5); and MVV (62±5). Residual volume (RV), RV/total lung capacity (TLC), VE, and REE were elevated. Other lung volumes were normal. Thus, obese children have altered pulmonary function, which is characterized by reductions in DLCO and ventilatory muscle endurance and airway narrowing. These alterations may reflect extrinsic mechanical compression on the lung and thorax, and/or intrinsic changes within the lung. The reduced DLCO may result from decreases in alevolar surface area relative to lung volume. Pediatr Pulmonol. 1993; 16:130–137. © 1993 Wiley‐Liss, Inc.
The effects of bedside pulmonary mechanics testing during infant mechanical ventilation: A retrospective analysis
Authors: Rosen William C. , Mammel Mark C. , Fisher Joel B. , Coleman J. Michael , Bing Dennis R. , Holloman Keith K. , Boros Stephen J. 
Published: March 2007

AbstractWe examined the effects of regular bedside testing of pulmonary mechanics (PM) on the outcome of 468 acutely ill, mechanically ventilated neonates. During the first of two 18‐month study periods, 217 infants were mechanically ventilated without the assistance of PM measurements. During the second 18‐month period, 251 infants were ventilated with the assistance of at least daily PM measurements. Using data obtained from the PM tests, we adjusted the infants' ventilators to maintain tidal volume, inspiratory time, and pressure‐volume loops within predetermined limits. With the exception of the PM measurements, given the limitations of retrospective analyses, both groups of infants received identical medical and nursing care. The infants ventilated with the assistance of PM testing developed fewer pneumothoraces (4.0%; 10/251) vs. no PM testing, 10.1 % (22/217); P < 0.05 by Chi‐square analysis. Infants weighing less than 1,500 g ventilated with the assistance of PM measurements had less intraventricular hemorrhage (IVH) overall, most notably, less grades I and II IVH (total IVH‐PM testing, 39.1% vs. no PM testing, 65.7%; P < 0.01; Grades I‐II IVH‐PM testing, 30.4% vs. no PM testing, 54.9%; P < 0.01). IVH incidence was decreased independent of pneumothorax occurrence. Survival rates, incidences of bronchopulmonary dysplasia, and durations of mechanical ventilation and hospitalization were similar. This retrospective analysis suggests that PM testing during infant mechanical ventilation reduces common acute ventilator‐associated complications. Pediatr Pulmonol. 1993; 16:147–152. © 1993 Wiley‐Liss, Inc.
Continuous end‐tidal CO2 in pediatric bronchoscopy
Authors: Franchi Luis M. , Carlos Maggi J. , Nussbaum Eliezer 
Published: March 2007

AbstractIn recent years flexible fiberoptic bronchoscopy (FFB) has been applied to children for diagnostic and therapeutic purposes. Sedation during FFB. along with the introduction of the bronchoscope into the pediatric airway, may cause hypoventilation, leading to hypoxia and desaturation, even in the presence of oxygen supplementation. Arterial oxygen saturation is usually monitored by pulse oximetry (S) during FFB. End‐tidal P (P) monitoring is not routinely used. Twenty‐two pediatric patients (15 days to 18 years old) undergoing FFB and receiving supplemental oxygen were studied prospectively and had continuous P and S measured before and during the procedure (bronchoscope at the carina or either main bronchus). Mean P (±SD) decreased from 33.9 (±6.0) mmHg before to 27.1 (±12.1) mmHg during the procedure (P < 0.024). Concomitantly, mean S (±SD) also decreased from 99.9 (±0.4)% before to 95.7 (±11.1)% during the procedure (P < 0.015). P changes seemed to precede the variations in S, especially in young patients who experienced significant desaturation and decompensation during FFB. We conclude that P and S decrease during FFB in children, even with supplemental oxygen. We speculate that this reflects airway obstruction by the instrument. Further studies are needed to assess the utility of P monitoring in pediatric FFB. Pediatr Pulmonol. 1993; 16:153–157. © 1993 Wiley‐Liss, Inc.
The effect of age on oxygen desaturation during histamine inhalation challenge in normal infants
Authors: Young Sally , Geelhoed Gary C. , Stick Stephen M. , Landau Louis I. , Lesouéuf Peter N. 
Published: March 2007

AbstractArterial oxygen saturation (S) is usually measured during inhalation challenges in infants as desaturation has been demonstrated with provoked bronchoconstriction. We wished to examine whether measurement of S would provide a simple noninvasive indicator of respiratory function (RF) changes occuring during inhalation challenge in infants. Histamine inhalation challenges were performed longitudinally in 22 normal healthy infants at 4 and 26 weeks of age. RF was measured by calculating maximum forced expiratory flow at functional residual capacity (VmaxFRC) using the rapid thoracic compression technique. Airway responsiveness was assessed using histamine; the provoking concentration (PC) was that which caused a fall in VmaxFRC of at least 40% from baseline. The provocative concentration for an exact fall of 40% in VmaxFRC (PC40) from baseline was derived by linear interpolation. S was continuously monitored by pulse oximetty. One month old infants had higher S levels throughout the inhalation challenge in comparison to their S levels at 6 months of age. Significant falls in S, were observed at the PC at both ages. However, at the age of 26 weeks the infants had greater median falls in S [PC, 4.5% (95%Cl: 3.0, 7.0)] compared to the response at age 4 weeks [3.0% (95%Cl: 1.0, 4.0) (P < 0.01)]. Median falls in VmaxFRC at the PC were not different between the ages. These results indicate an age‐dependent discordance between airway and S response in healthy infants during histamine‐induced bronchoconstriction. Pediatr Pulmonol. 1993; 16:158–162. © 1993 Wiley‐Liss, Inc.
Continuous positive airway pressure by nasal prongs in bronchiolitis
Authors: Soong Wen‐Jue , Hwang Betau , Tang Ren‐Bin 
Published: March 2007

AbstractTen infants with evidence of impending respiratory failure from severe bronchiolitis were successfully treated with continuous positive airway pressure (NCPAP) with double nasal prongs. Their mean (SD) age was 6.7 (3.8) months and mean (SD) body weight was 7.1 (2.1) kg. Respiratory assessments were made immediately before and 2 hours after application of NCPAP. Clinical symptoms, signs, and arterial blood gases improved in all patients, with a significant fall in mean (SD) respiratory rate [71 (6) vs. 54 (9) per minute], mean (SD) heart rate (178 (9) vs. 154 (15) per minute], and mean (SD) partial pressure of arterial carbon dioxide (Pa; 48.0 (13.9) vs. 42.4 (12.9) mmHg]. There was a significant rise in mean (SD) arterial blood pH 33 (0.05) vs. 7.37 (0.05)) and mean (SD) oxygenation ratio [Fio2/Pao2, 155 (25) vs. 175 (22)]. We believe NCPAP is an effective method, with numerous advantages in the treatment of severe bronchiolitis. Early application of NCPAP is suggested to avoid the need for mechanical ventilation. Pediatr Pulmonol. 1993; 16:163–166. © 1993 Wiley‐Liss, Inc.
Comparison of helium dilution and nitrogen washout measurements of functional residual capacity in premature infants
Authors: Yuksel B. , Greenough A. , Chan V. , Russell R. Ross 
Published: March 2007

AbstractComparison has been made of measurements of functional residue capacity (FRC) by a helium gas dilution (He) and a nitrogen washout (N2) technique. Twenty infants (median gestational age, 29.5 weeks) were studied at a median postnatal age of 25 days. No infant was oxygen dependent. The coefficient of repeatability of FRC (He) was 6.4 mL/kg and of FRC (N2), 6.3 mL/kg. The coefficient of repeatability of the two methods combined was 13.8 mL/kg. In 10 infants the results of two techniques differed by more than 20% of the mean FRC; those infants were born at a significantly earlier gestation than the rest of the cohort (P < 0.01). We conclude that, except in very immature infants, techniques for measuring FRC (He) and FRC (N2) yield reproducible and comparable results in convalescent premature infants. Pediatr Pulmonol. Pediatr Pulmonol. 1993; 16:197–200. © 1993 Wiley‐Liss, Inc.
Regional Distribution of Myosin Heavy Chain Isoforms in Rib Cage Muscles as a Function of Postnatal Development
Authors: Vazquez Roger L. , Daood Molly , Watchko Jon F. 
Published: March 2007

AbstractWe studied the expression of myosin heavy chain (MHC) isoforms, utilizing electro‐phoretic methods, in rib cage (RC) muscles: the scalenus medius, the parasternal, cephalic, midthoracic, and caudal intercostal muscles; and in the diaphragm (DI) of rats during postnatal development and when mature. At day 1, all RC muscles and the DI expressed MHC neonatall embryonic (6942% of total MHC complement) with little MHC slow and 2A; the RC muscles alone expressed a small proportion of MHC 2B (24%). On day 4, MHC neonatallembryonic expression still predominated (55–71%) but increased MHC 2A expression was observed in both the RC (11–21%) and DI (31%); MHC 28 (57%) was noted in the RC muscles but not the DI. By day 14, MHC neonatallembryonic and 2A expression each comprised a third of the total MHC complement of the RC muscles, MHC 2X was first observed, and MHC 2B expression increased. The day 14 DI was comprised of equal proportions of MHC neonatal/embryonic, slow and 2A with little MHC 2X (11%). The adult and day 30 animals expressed comparable muscle‐specific MHC phenotypes: the DI characterized by a proportional mixture of MHC slow, MHC 2A, and MHC 2X, with little MHC 26, whereas the RC muscles expressed predominately MHC 28 (40–62%). We conclude that the RC muscles and DI show comparable MHC phenotypes in the immediate newborn period but differ in their MHC expression during postnatal development and when mature. The RC muscles show only minor intermuscle variations in MHC phenotype during development, and when mature are characterized by fast MHC isoform expression, particularly MHC 2B. Pediatr Pulmonol. 1993; 16:289–296. © 1993 Wiley‐Liss, Inc.
Low‐frequency vs. High‐frequency respiratory mechanics after methacholine challenge in artificially ventilated rabbits
Authors: Belaguid A. , Marchal F. , Mazurek H. , Hascoet J. M. , Peslin R. 
Published: March 2007

AbstractRespiratory system resistance (Rrs) and elastance (Ers) were estimated by two methods, before and after methacholine in six anesthetized, paralyzed, and artificially ventilated rabbits. Rrs and Ers, were obtained (1) by multiple linear regression analysis of the relationship between tracheal pressure and tidal volume and flow [Rrs (mlr)], Ers (mlr), and (2) by analysis of the Fourier transforms of tracheal pressure and flow resulting from 4 to 30 Hz pseudorandom pressure oscillations delivered by an Infant Star respirator [Rrs(os), Ers(os)]. Rrs (os) was significantly lower than Rrs (mlr). For instance, Rrs (os) at 20 Hz [Rrs (os)20] was (mean±SD) 17.3±3.5 vs 21.4±3.6 cm H2O · L−1 · s (P < 0.01) for Rrs (mlr). Ers (os) was significantly higher than the respective value obtained by multiple linear regression (718.2±81.0 vs 403.7±43.0 cm H2O L−1; P < 0.01). After methacholine, the changes of respiratory mechanics were similar with both methods. Rrs (mlr) and Rrs (os)20 increased respectively by 131±45 and 134±76%, and Ers(mlr) and Ers(os) increased respectively by 63±7 and 54±13%. A significant correlation was observed between Rrs(mlr) and Rrs (os)20 (r = 0.97) and between Ers (mlr) and Ers(os) (r = 0.96). We conclude that positive response to methacholine may be detected by forced oscillation as well as by multiple linear regression. However, the identified physiological components of the lung response (alteration in lung viscoelastic properties, increased lung inhomogeneity or increased intrathoracic airway shunt) are likely to be different with each method. Pediatr Pulmonol. 1993; 16:297–302. © 1993 Wiley‐Liss, Inc.
The effect of instrumental dead space on measurement of breathing pattern and pulmonary mechanics in the newborn
Authors: Marsh Michael J. , Ingram Dorothea , Milner Anthony D. 
Published: March 2007

AbstractThe effect of the instrumental dead space on breathing pattern and the values of pulmonary mechanics was evaluated because of concern about the relatively large dead space of 26 mL in a commercially available system. Sixty‐three healthy newborn infants were studied with a system as commercially supplied, and with the dead space eliminated using a 2 L/min biased flow. This led to a significant reduction in mean (± SD) values of respiratory rate from 56.8 (±11.7) to 48.2 (±11.7) breath/min (P < 0.0001), tidal volume from 5.2 (±1.3) to 4.9 (±0.9) mL/kg (P < 0.05), minute volume from 284 (±68) to 220 (±63) mL/min/kg (P < 0.0001), and work of breathing from 13.7 (±6.6) to 11.8 (±7.6) g · cm/kg (P < 0.02). There was a significant increase in dynamic lung compliance from 5.2 (±1.5) to 5.6 (±1.2) mL/cm H2O (P < 0.01) but no difference for total pulmonary resistance 39.6 (±22.8) and 38.8 (±22.2) cm H2O/L/sec. This shows that the instrumental dead space prevents measurement of the basal breathing patterns and alters the values of pulmonary mechanics. It is, therefore, important to use equipment with low dead space or make efforts to remove it by using a biased flow system such as we describe when measuring breathing patterns and pulmonary mechanics in the newborn. Pediatr Pulmonol. 1993; 16:316–322. © 1993 Wiley‐Liss, Inc.
Severe hypoxemia in children with upper airway obstruction during sleep does not lead to significant changes in heart rate
Authors: D'Andrea Lynn A. , Rosen Carol L. , Haddad Gabriel G. 
Published: March 2007

AbstractLife‐threatening cardiac arrhythmias, including bradyrhythmias, are well‐known sequelae of obstructive sleep apnea syndrome (OSAS) in adults and are associated with apnea and severe hypoxemia. Since the clinical expression of OSAS in children is different, we questioned whether arrhythmias are a common feature of pediatric OSAS. Therefore, we analyzed R‐R interval patterns from 12 subjects (age 8 months to 14 years) with OSAS in detail. The diagnosis of pediatric OSAS is based on clinical signs of loud snoring and paradoxical respiratory efforts, as well as elevated end‐tidal carbon dioxide tension (PETCO2) and major phasic decreases of oxyhemoglobin saturation (SaO2). Two hundred and nine episodes of severe hypoxemia, defined as SaO2 values ⩽85% lasting ⩾30 seconds, were identified. Only 29 (14%) of these episodes were associated with obstructive apneas. The R‐R intervals were analyzed before and during each desaturation. Compared to baseline, mean and minimum R‐R intervals (RR,mean, RRmin) decreased during the desaturation episodes (P < 0.05), while maximum R‐R interval (RRmax) increased (P < 0.05). Although the absolute changes in all parameters were significantly different from baseline, the magnitude of these changes was small, with a mean of −5.3%, −12.2%, and 10.4% for RRmean, RRmin, and RRmax, respectively. No child had life‐threatening arrhythmias. Although severe hypoxemia existed in these children, the magnitude of the R‐R interval changes was modest, and profound bradycardia as described in adults, was rare. We conclude that in children with suspected OSAS, changes in R‐R interval and presence of life‐threatening arrhythmias cannot be used as a screening tool to assess the severity of disease or blood gas abnormalities. We speculate that the difference in heart rate patterns between children and adults may depend, in part, on the degree of airway closure and associated changes in pleural pressure. Pediatr Pulmonol. 1993; 16:362–369. © 1993 Wiley‐Liss, Inc.
C‐reactive protein is not a useful indicator of intermittent bacterial colonization in early lung disease of patients with cystic fibrosis
Authors: Watkin S. L. , Elborn J. S. , Cordon S. M. , Hiller E. J. , Shale D. J. 
Published: March 2007

AbstractC‐reactive protein (CRP) is a general marker of the systemic inflammatory response to bacterial infection. Serial measurement of CRP is useful in monitoring respiratory exacerbations in patients with cystic fibrosis (CF) and chronic infection with Pseudornonas aeruginosa. We hypothesized that regular monitoring of CRP in young children with CF prior to colonization with P. aeruginosa might provide an objective guide to the need for antibiotic treatment. Twenty‐two children were studied prospectively over a 6 month period. We measured CRP every 2 months and at the beginning and end of respiratory exacerbations. In samples taken when the children were well, median CRP was 0.45 μg/mL compared with 1.92 μg/mL when they were symptomatic with positive culture results (P < 0.05). Despite this difference there was considerable overlap between CRP levels for infected and noninfected patients. A CRP value of >1.82 μg/mL (the upper 95% confidence interval for a control group of well children without CF) had a sensitivity of 49% and a specificity of 83% in determining a symptomatic exacerbation. We conclude that in this group of patients CRP measurements were of little value in monitoring respiratory exacerbations in patients who become intermittently infected with either Haernophilus influenzae or Staphylococcus aureus. Pediatr Pulmonol. 1994; 17:6–10. © 1994 Wiley‐Liss, Inc.
Perinatal lung development following maternal exposure to methylmercuric chloride
Authors: Das R. M. , Scott J. E. 
Published: March 2007

AbstractMercury ingested from dietary sources has potent neurotoxic and teratogenic effects. Initial studies have shown that mercury may also affect fetal lung development. Since these pulmonary effects may play a role in subsequent neonatal morbidity and mortality due to compromising of the development of the lung, mercury effects in fetal and neonatal lung were investigated. Methylmercuric chloride (MMC), 1,000 ppm (15 mg/kg of body weight), was administered via an intragastric tube to timed‐pregnant Swiss/Webster mice on day 9 of gestation. Lungs from fetuses on gestational day 18 and from neonates on days 1, 5, or 10 after birth were studied. Significant changes in MMC‐exposed lungs compared to controls occurred at postnatal day 1. At this time, lung weight per gram body weight increased, phospholipid content per gram of lung or per microgram of DNA decreased, while DNA per gram of lung increased. Methylmercury appears to have delayed lung maturation. Cuboidal epithelial cells in alveolar tubules contained conspicuous glycogen deposits, and differentiation of alveolar type II cells was adversely affected. These results suggest that prenatal exposure to methylmercury may be detrimental to lung development, specifically to the initiation of surfactant synthesis, by delaying the normal pattern of maturation of the alveolar type II cells within the lungs. Pediatr Pulmonol. 1994; 17:11–21. © 1994 Wiley‐Liss. Inc.
Use of BiPAP® by nasal mask in the treatment of respiratory insufficiency in pediatric patients: Preliminary investigation
Authors: Padman Raj , Lawless Stephen , Von Nessen Susan 
Published: March 2007

AbstractA device for nasally applied bilevel positive airway pressure, BiPAP® (Respironics Inc., Murrysville, PA), is currently being evaluated for the treatment of respiratory failure in pediatric and adult patients. This retrospective case review examines our experience with using BiPAP in the treatment of acute ventilatory deterioration in pediatric patients with chronic respiratory insufficiency. All patients who presented to the intensive care unit with chronic respiratory insufficiency and ventilatory failure but without hypoxia were given a trial on BiPAP. Fifteen patients, ages 4–21 years, received such ventilatory support. Four of them had cystic fibrosis (CF) and 11 had neuromuscular disease (2, spinal muscular atrophy; 7, Duchenne muscular dystrophy; 1, spinal cord injury; and 1, myopathy of undetermined origin). Hospital days, respiratory rates, resting heart rates, arterial blood gases, serum bicarbonates, and subjective assessment by parents and or patients of dyspnea, sleep pattern, and activity tolerance were compared prior to and after initiation of BiPAP. Patients were followed from 1 day to 21 months. In 14 of 15 patients placement of an artificial airway could be avoided. Significant decreases in hospital days, respiratory rate, heart rate, serum bicarbonate, and arterial P were observed after initiation of BiPAP. Decline in dyspnea (87% with severe distress at rest prior vs. 80% comfortable at rest after BiPAP), increased activity tolerance (57% attending school after BiPAP vs. none prior to BiPAP), and improved quality of sleep (93% with cornfortable sleep, no daytime somnolence vs. none with comfortable sleep and 36% with daytime somnolence prior to BiPAP). After initiation of BiPAP, all patients were managed outside of the intensive care unit and hospital days declined or, in 4 patients with CF, lung transplantation was done. No major complications occurred. Bilevel positive airway pressure appears to be a promising, safe, noninvasive modality for the treatment of acute and/or chronic respiratory failure in pediatric patients with chronic respiratory diseases. Pediatr Pulmonol. 1994; 17:119–123. © 1994 Wiley‐Liss, Inc.