RESUMEN
Few studies have evaluated clofazimine (CLOF) drug monitoring and safety in children. We treated 10 children, 8 with CF, for NTM infection with multiple antimicrobials, including CLOF. All had serial blood CLOF concentrations measured and were followed for adverse events. Despite CLOF dose escalation, most children with CF did not reach a target CLOF concentration. Our data suggest that children with CF may require earlier initiation of CLOF at higher doses than is currently recommended.
Asunto(s)
Fibrosis Quística , Infecciones por Mycobacterium no Tuberculosas , Niño , Clofazimina , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Humanos , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/etiología , Micobacterias no TuberculosasRESUMEN
STUDY OBJECTIVE: To estimate the incidence of respiratory symptoms and physiologic abnormalities after inhalation of common irritant chemicals. DESIGN: Structured interview of 12 months of poison control center (PCC) inhalation cases. Follow-up measurement of pulmonary function and airway responsiveness in a subgroup with symptoms 12 to 24 h postexposure. SETTING: A regional PCC and clinical pulmonary function laboratory. PATIENTS: Consecutive sample of 547 inhalation cases. Interviews of 299 subjects. Lung function follow-up in 10 subjects. MEASUREMENTS AND MAIN RESULTS: Immediate respiratory symptoms were reported by 262 (88 percent) subjects; 12 to 24 h postexposure symptoms were reported by 130 (44 percent). Cigarette smoking was significantly related to immediate onset of cough (relative risk [RR] = 1.3; 95 percent confidence interval [CI], 1.1 to 1.5); both smoking (RR = 1.6; 95 percent CI, 1.1 to 2.1) and prior asthma (RR = 1.3; 95 percent CI, 1.1 to 1.6) were associated with wheeze, exhibiting multiplicative combined risk (RR = 2.8; 95 percent CI, 1.9 to 4.3). Of 10 subjects studied, none had abnormal airflow or lung volumes 8 +/- 4 days postexposure; 8 demonstrated increased airway responsiveness to methacholine. By three months, only one subject's increased responsiveness reversed; in three others, symptoms resolved but increased responsiveness remained. CONCLUSIONS: Respiratory symptoms following irritant exposure are associated with smoking and asthma and typically resolve quickly. Continuing symptoms are associated with persistent increased airway responsiveness without other pulmonary function abnormalities. This may reflect newly induced airway changes or, alternatively, could represent underlying increased responsiveness in subjects symptomatic after irritant exposure.
Asunto(s)
Irritantes , Mecánica Respiratoria , Enfermedades Respiratorias/inducido químicamente , Enfermedades Respiratorias/fisiopatología , Administración por Inhalación , Adulto , Asma/complicaciones , Pruebas de Provocación Bronquial , Exposición a Riesgos Ambientales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/fisiopatología , Fumar/efectos adversosRESUMEN
BACKGROUND: We recently showed the clinical benefit of the PFP-2 vaccine for respiratory syncytial virus (RSV) for children with cystic fibrosis (CF). OBJECTIVE: To determine the safety and immunogenicity of yearly sequential administration of the PFP-2 vaccine in CF children. STUDY DESIGN: Twenty-nine of the 34 CF children who participated in the previous study were enrolled in this open label vaccine study. All of the CF children ages 2.6 to 8.9 years received the PFP-2 vaccine, the PFP/PFP group received the PFP-2 vaccine in 1993 and 1994 and the saline/PFP group received the vaccine for the first time in 1994. At entry demographic data and measurements of lung function and nutrition were collected. Microneutralization test, enzyme-linked immunosorbent assay to F protein and Western blot assay were performed on plasma drawn before and 4 weeks after vaccination and at the end of the RSV season. During the study weekly telephone calls were made and acute respiratory illnesses were evaluated. RESULTS: Baseline measurements were similar between groups. Systemic and local vaccine reactions were mild and similar for both groups. A 4-fold or greater neutralizing antibody rise to RSV occurred in 4 of 14 (28.6%) and 9 of 14 (64.3%) in PFP/PFP and saline/PFP groups (P = 0.13), respectively. Four children in the PFP/PFP group and 7 in the saline/PFP group were infected with RSV. A reduction in lower respiratory illnesses (1.0 vs. 2.0), antibiotic courses (2.5 vs. 5.6) and days of illnesses (37.3 vs. 93.1) was observed in the PFP/PFP vaccinees infected with RSV compared with the saline/PFP group (t test; P < or = 0.05). One death occurred in the PFP/PFP group; the cause of death was consistent with septic shock and unrelated to vaccination or RSV infection. CONCLUSION: Sequential annual PFP-2 vaccination was safe and not associated with exaggerated respiratory disease.
Asunto(s)
Proteína HN , Infecciones por Virus Sincitial Respiratorio/prevención & control , Virus Sincitiales Respiratorios/inmunología , Proteínas Virales de Fusión/inmunología , Proteínas Virales/inmunología , Vacunas Virales/inmunología , Anticuerpos Antivirales/biosíntesis , Niño , Preescolar , Fibrosis Quística/complicaciones , Fibrosis Quística/inmunología , Femenino , Humanos , Masculino , Infecciones por Virus Sincitial Respiratorio/complicaciones , Vacunación , Proteínas del Envoltorio Viral , Vacunas Virales/administración & dosificaciónRESUMEN
OBJECTIVE: To test in a double blind, placebo-controlled study a purified fusion protein (PFP-2) vaccine against respiratory syncytial virus (RSV) in RSV-seropositive children with cystic fibrosis (CF). METHODS: Seventeen CF children, mean age 4.5 years, received PFP-2 vaccine and 17 CF children, mean age 5.8 years, received a saline vaccine. At enrollment the Shwachman clinical score, Brasfield radiographic score, oxygen saturation (SpO2), anthropometric indices and other variables were recorded. After vaccination the reactions were assessed daily for 7 days. During the RSV season weekly telephone interviews were performed and children with an acute respiratory illness were evaluated and cultured for RSV. Serum was drawn before vaccination, 1 month after vaccination and at the end of the RSV season and tested for antibodies to RSV. RESULTS: Other than age the baseline measurements at enrollment were similar between groups. The PFP-2 vaccine produced mild local reactions and induced a significant neutralizing antibody response in two-thirds of the vaccinees and a significant enzyme-linked immunosorbent assay-fusion glycoprotein antibody response in nearly all the PFP-2 vaccinees. Vaccine-enhanced disease was not observed in PFP-2 vaccines infected with RSV. Protection against RSV infection was not observed; however, a significant reduction (t test, P < 0.01) in mean number of lower respiratory tract illnesses (0.8 vs. 2.1), antibiotic courses (2.2 vs 4.5) and days ill (30.5 vs. 67) occurred among RSV-infected PFP-2 vaccinees. CONCLUSIONS: Efficacy of the PFP-2 vaccine against lower respiratory tract illness during the RSV season was shown in RSV-seropositive children with CF.
Asunto(s)
Fibrosis Quística/virología , Proteína HN , Infecciones por Virus Sincitial Respiratorio/prevención & control , Vacunación , Proteínas Virales/inmunología , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Fibrosis Quística/complicaciones , Método Doble Ciego , Ambiente , Humanos , Lactante , Placebos , Infecciones por Virus Sincitial Respiratorio/complicaciones , Infecciones por Virus Sincitial Respiratorio/inmunología , Virus Sincitiales Respiratorios/química , Virus Sincitiales Respiratorios/inmunología , Virus Sincitiales Respiratorios/aislamiento & purificación , Índice de Severidad de la Enfermedad , Vacunas Sintéticas/efectos adversos , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/uso terapéutico , Proteínas del Envoltorio Viral , Vacunas Virales/efectos adversos , Vacunas Virales/inmunología , Vacunas Virales/uso terapéuticoRESUMEN
We used the willingness-to-pay (WTP) method to value the benefits of poison control centers when direct access was blocked, comparing WTP among: (1) blocked callers (n = 396), (2) callers after access was restored (n = 418), and (3) the general population (n = 119). Mean monthly WTP was $6.70 (blocked callers), $6.11 (non-blocked callers), and $2.55 (general population). Blocked and non-blocked callers had a significantly higher WTP than general population respondents (p < 0.001). We conclude that the WTP method measured benefits that are difficult to quantify; however, WTP surveys need to be carefully conducted to minimize bias. We discuss how this approach could be useful for other health care services.
Asunto(s)
Líneas Directas/economía , Centros de Control de Intoxicaciones/economía , Análisis Costo-Beneficio , Encuestas de Atención de la Salud/métodos , Accesibilidad a los Servicios de Salud , Modelos Econométricos , Centros de Control de Intoxicaciones/estadística & datos numéricos , Análisis de Regresión , San Francisco , Impuestos , Estados UnidosRESUMEN
Meconium ileus (MEC), failure to thrive (FTT), and a combination of FTT and pulmonary symptoms (COMB) are the most frequent symptoms of cystic fibrosis (CF) at the time of diagnosis. The purpose of this study was to compare to normal controls (NC) the pulmonary function of CF infants at the time of diagnosis, when grouped by these symptoms. The measurements of pulmonary function included oxygen saturation (SaO2), functional residual capacity (FRC), mixing index (MI), total respiratory system compliance (Crs), and maximal flow at FRC (VmaxFRC). Compared to NC (n = 33), the MEC group (n = 5) had a higher MI (54 vs. 42%) and no difference in SaO2, Crs or VmaxFRC. There were no significant differences between FTT (n = 8) and NC groups although there was a tendency for Crs to be lower in the FTT group (5.1 vs. 6.8 ml/cm H2O). When compared to all other groups, the COMB group (n = 11) had significantly lower SaO2, MI, Crs, and VmaxFRC. The normal lung function in the MEC group is consistent with the normal anatomy reported in CF infants dying secondary to meconium ileus. Longitudinal evaluation of the infants in this study, following initiation of care as patients with a diagnosis of CF, may allow us to determine whether symptoms at diagnosis remain an important determinant of lung function in infancy.
Asunto(s)
Fibrosis Quística/fisiopatología , Capacidad Residual Funcional , Rendimiento Pulmonar , Mediciones del Volumen Pulmonar , Fibrosis Quística/diagnóstico , Insuficiencia de Crecimiento/fisiopatología , Humanos , Lactante , Obstrucción Intestinal/fisiopatología , Pulmón/fisiopatología , MeconioRESUMEN
Respiratory syncytial virus (RSV) is the most important cause of bronchiolitis and pneumonia in young children. The development of an animal model of RSV disease serves to better understanding the pathophysiology of airway disease from RSV infection in infants and children. Groups of six lambs were inoculated intratracheally (IT) or intranasally (IN) with a human strain of RSV (H-RSV). For controls 8 lambs received IT virus-free cell lysate. Tachypnea and fever were observed significantly more often following IT than following IN inoculation of H-RSV or IT placebo (for tachypnea: 20 of 69 days, 5 of 63 days, and 3 of 89 days, respectively, P < 0.001; for fever: 6 of 69 days, 0 of 63 days, and 1 of 89 days, respectively, P < 0.02). Nasal fluid production was significantly more frequent in both IT (14 of 69 days) and IN (15 of 63 days) groups than in the placebo group (2 of 87 days, P < 0.001). Postvaccination geometric mean titers (GMT, arithmetic transformation of log 2) of RSV-specific neutralizing antibody were significantly increased in the IT H-RSV group compared with postplacebo GMTs at 1 week (72 vs. 6.7, P < 0.03). By the second week postinoculation both H-RSV-infected groups had comparable levels of RSV-specific neutralizing antibody titers and had significantly greater GMTs for the second through to the fourth week than the placebo group (144, 128, and 4.8, respectively P < 0.0008). Bacterial isolates of the upper airway were comparable among the three groups. Histopathology at day 28 postinoculation was unremarkable for the three study groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Virus Sincitiales Respiratorios , Infecciones por Respirovirus/fisiopatología , Animales , Animales Recién Nacidos , Femenino , Humanos , Masculino , Modelos Biológicos , Infecciones por Respirovirus/complicaciones , Infecciones por Respirovirus/microbiología , OvinosRESUMEN
The objective of this study was to assess the diagnostic accuracy of oropharyngeal (OP) cultures relative to simultaneous bronchoalveolar lavage (BAL) cultures in very young children with CF, and to examine the effects of bacterial density, age, and study cohort on diagnostic accuracy. Respiratory culture data were analyzed from three independent, prospective studies involving simultaneous collection of 286 OP and BAL cultures from 141 children with CF <5 years of age. For predicting any growth of Pseudomonas aeruginosa (Pa) from the lower airway in subjects =18 months of age (mean age, 8 +/- 5 months), OP cultures had a sensitivity of 44% (95% CI 14%, 79%), specificity of 95% (90%, 99%), positive predictive value of 44% (14%, 79%), and negative predictive value of 95% (90%, 99%). Diagnostic accuracy was similar for Haemophilus influenzae (Hi). Specificity was significantly lower for Staphylococcus aureus (Sa). Sensitivity for all organisms improved if a positive lower airway culture was defined as >/=10(3) or >/=10(5) cfu/mL. Specificity for Pa declined significantly with increasing age. In children with CF <5 years of age, the specificity and negative predictive value of OP cultures for Pa are high, while the sensitivity and positive predictive value are poor. Thus, in this age range, a negative throat culture is helpful in "ruling out" lower airway infection with Pa. However, a positive culture does not reliably "rule in" the presence of Pa in the lower respiratory tract. These findings may have implications for study design and interpretation as well as clinical management of young children with CF.
Asunto(s)
Infecciones Bacterianas/diagnóstico , Fibrosis Quística/complicaciones , Orofaringe/microbiología , Infecciones Bacterianas/complicaciones , Líquido del Lavado Bronquioalveolar/microbiología , Broncoscopía , Preescolar , Fibrosis Quística/microbiología , Femenino , Humanos , Lactante , Masculino , Valor Predictivo de las Pruebas , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/microbiología , Sensibilidad y EspecificidadRESUMEN
Our objective was to describe the respiratory complications, clinical findings, and chest radiographic changes in the first year of life in infected and uninfected children born to HIV-1-infected women. We prospectively followed a cohort of 600 infants born to HIV-1-infected women from birth to 12 months in a multicenter study. Of these, 93 infants (15.5%) were HIV-1-infected, 463 were uninfected, and 44 were of unknown status prior to death or loss to follow-up. The cumulative incidence ( +/- SE) of an initial pneumonia episode at 12 months was 24.1 +/- 4.7% in HIV-1-infected children compared to 1.4 +/- 0.6% in HIV-1-uninfected children (P < 0.001). The rate of Pneumocystis carinii pneumonia (PCP) was 9.5 per 100 child-years. The HIV-1 RNA load was not higher in the group that developed pneumonia in the first year vs. those who did not. Children who developed lower respiratory tract infections or PCP had increased rates of decline of CD4 cell counts during the first 6 months of life. Lower maternal CD4 cell counts were associated with higher rates of pneumonia, and upper and lower respiratory tract infections. The rates of upper respiratory tract infection and bronchiolitis/reactive airway disease in infected children were not significantly different than in uninfected children. At 12 months, significantly more HIV-1-infected than uninfected children had tachypnea and chest radiographs with nodular and reticular densities. There was no relationship between cytomegalovirus infection in the first year of life and radiographic changes or occurrences of pneumonia. In conclusion, despite a low incidence of PCP, rates of pneumonia remain high in HIV-infected children in the first year of life. The incidence of pneumonia in uninfected infants born to HIV-1-infected mothers is low. Chest X-ray abnormalities and tachypnea suggest that subacute disease is present in infected infants. Further follow-up is warranted to determine its nature.
Asunto(s)
Infecciones por VIH/complicaciones , Neumonía por Pneumocystis/etiología , Complicaciones Infecciosas del Embarazo/microbiología , Enfermedades Respiratorias/epidemiología , Adulto , Estudios de Cohortes , Femenino , VIH-1 , Humanos , Incidencia , Lactante , Bienestar del Lactante , Recién Nacido , Masculino , Embarazo , Enfermedades Respiratorias/etiología , Factores de RiesgoRESUMEN
A thorough understanding of the early natural history of cystic fibrosis (CF) lung disease is critical for the development of effective interventions in the youngest patients. We assessed the evolution of pulmonary infection, inflammation, and clinical course among 40 infants over a 2-year period through annual bronchoalveolar lavage (BAL) for culture and measurements of pro- and anti-inflammatory cytokines, semiannual infant pulmonary function testing, and quarterly clinical evaluations. Both the prevalence of CF pathogens and their density in BAL fluid increased with age. Infants had neutrophilic lower airway inflammation and elevated IL-8 concentrations independent of whether CF pathogens were recovered. Total leukocyte and neutrophil densities and IL-8 concentrations increased with density of CF pathogens in BAL fluid, whether the isolated organism was P. aeruginosa or another pathogen. IL-10 concentrations were similar in CF subjects and non-CF historical controls. Infants generally had suboptimal growth (low weight and height percentiles) and obstructive lung disease (decreased expiratory flows and air trapping). Subjects from whom CF pathogens were isolated at > 10(5) cfu/mL had the worst air trapping and lowest Brasfield chest X-ray scores. Our findings provide a foundation for future studies of early intervention in CF lung disease, including antimicrobial and anti-inflammatory therapy.
Asunto(s)
Fibrosis Quística/fisiopatología , Líquido del Lavado Bronquioalveolar , Broncoscopía , Preescolar , Citocinas/análisis , Femenino , Humanos , Lactante , Mediadores de Inflamación/análisis , Masculino , Estudios Prospectivos , Factor de Necrosis Tumoral alfa/análisisRESUMEN
Using a double-blind, placebo-control, crossover study design, 8 asthmatic children (8-15 years) were evaluated for temporal patterns in airways function throughout separate study periods when treatment was placebo or Theo-24 once-daily on separate occasions at 0600, 1500 or 2100 hr. During 39-hr in-hospital observations, pulmonary function and serum theophylline concentrations (STC) were assessed every 3 hr under all treatments. The pharmacokinetics of Theo-24 varied greatly depending on the dosing time. For the afternoon and evening dosings, the Cmax, Tmax, AUC, % swing, % fluctuation, % AUC fluctuation, % nocturnal excess and Cav(2-6 hr) were all statistically significantly greater than for the morning dosing. Compared with the placebo regimen, dosing patients with Theo-24 at 1500 hr disrupted circadian patterns of airways function, especially airways patency, while dosing at 2100 hr, reduced the amplitude and shifted the acrophase of several spirometric measures to a slightly earlier time. Theo-24 treatment irrespective of dosing time resulted in comparable enhancement of the group 24-hr mean, minimum and maximum values of airways patency with reference to placebo baselines. Theo-24 dosing at 1500 or 2100 hr, however, resulted in the best effect on the airways as assessed by the 24-hr mean FEV 1.0 level in 7 of the 8 asthmatic children. When the drug was given at 1500 hr, the time of lowest FEV 1.0 was shifted from the nighttime hours in 5 of 8 patients. These findings suggest that clinicians need to individualize the theophylline dosing schedule of patients to best control the symptoms of asthma.
Asunto(s)
Asma/tratamiento farmacológico , Teofilina/administración & dosificación , Asma/metabolismo , Asma/fisiopatología , Niño , Ritmo Circadiano , Ensayos Clínicos como Asunto , Preparaciones de Acción Retardada , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Pruebas de Función Respiratoria , Teofilina/farmacocinéticaRESUMEN
Potential day-night differences of theophylline absorption and disposition were examined in day-active asthmatic children. Theophylline was given orally as TheoDur tablets and Somophyllin-CRT capsules (random crossover) every 12 hr (0700 and 1900), and patients were studied during two consecutive dosing intervals. In addition, patients were studied during the last 24 hr of a 48-hr continuous, intravenous aminophylline infusion. Serum theophylline concentrations were essentially constant during the intravenous infusion for the day and night periods. Thus, day and night clearances were nearly identical. Following oral administration of Somophyllin-CRT or TheoDur, areas under the serum concentration-time curves were greater during the day than the night, with Somophyllin-CRT yielding greater areas than TheoDur for both dosing intervals. Theophylline was absorbed more rapidly during the day than the night, as evidenced by a time to maximum concentration that occurred earlier in the daytime dosing interval. We conclude that theophylline clearance is not characterized by a circadian rhythm and that absorption of theophylline from Somophyllin-CRT and TheoDur is more rapid and complete during the day than the night.
Asunto(s)
Asma/tratamiento farmacológico , Ritmo Circadiano/efectos de los fármacos , Teofilina/farmacocinética , Administración Oral , Adolescente , Asma/fisiopatología , Niño , Preparaciones de Acción Retardada , Femenino , Humanos , Masculino , Teofilina/administración & dosificación , Teofilina/uso terapéuticoRESUMEN
BACKGROUND/PURPOSE: The T-tube ileostomy was first used at Texas Children's Hospital in 1959. The purpose of this study is to update the experience since the initial report of this technique in 1981. METHODS: A database of 448 patients with cystic fibrosis (CF) seen in the authors' institution was used to identify 83 patients (18.5%) who presented with meconium ileus. The clinic and hospital charts of these patients were reviewed retrospectively to identify patients who had undergone placement of a T-tube ileostomy. RESULTS: Surgery was performed in 60 of 83 patients for complications of meconium ileus or failure to evacuate the meconium after a contrast enema. Of these patients, 21 of 60 (35%) underwent placement of a T-tube ileostomy. An additional 8 patients were identified who underwent placement of a T-tube ileostomy but were not included in the CF database, for a total of 29 patients who have been treated with T-tube ileostomy since 1959 at Texas Children's Hospital. Five patients were excluded from analysis because of insufficient data or misdiagnosis. One of the 24 patients in the series died of complications of prematurity. A total of 20 of 23 patients had resolution of their meconium ileus after T-tube irrigation with n-acetylcysteine or pancreatic enzymes. Three patients required additional surgery to relieve persistent bowel obstruction. All patients had the T-tube removed within the first 8 weeks after surgery. Two patients required subsequent repair of an incisional hernia. There were otherwise no complications of this procedure, with an average follow-up of 11.5 years. CONCLUSION: In patients with uncomplicated meconium ileus unrelieved by contrast enema, the T-tube ileostomy is an effective and safe treatment.
Asunto(s)
Fibrosis Quística/complicaciones , Ileostomía/métodos , Obstrucción Intestinal/cirugía , Humanos , Recién Nacido , Obstrucción Intestinal/etiología , MeconioRESUMEN
BACKGROUND: Poison Control Centers (PCCs) provide telephone consultations to manage poisonings. They are threatened with funding loss. Policy decision-makers have requested an evaluation of alternate models for telephone management of poisonings. OBJECTIVE: We examined the feasibility of alternative models for the telephone management of poisonings from the public. METHODS: Alternative models evaluated included emergency medical dispatchers (EMDs), advice nurses (RNs), and poison information providers (PIPs) to manage real and hypothetical poisonings with protocols or computerized references (Poisindex) with and without PCC backup. RESULTS: EMDs and RNs with a structured protocol and access to a PCC specialist were able to manage a small subset of poisoning calls. EMDs and RNs managed 6% and 12% of poisoning calls respectively. Non-protocol management of hypothetical cases using Poisindex resulted in mismanagement of cases and longer periods of time to manage cases. PIPs within a PCC were able to manage a substantially greater proportion of calls, but had a significant portion of non-productive time waiting for a PCC call. CONCLUSION: EMDs, RNs, and technician-level PIPs can manage a subset of poisoning cases using structured protocols. Alternative providers were dependent on PCC staff for consultation of the majority of poisoning calls. There are several obstacles to these models and their cost-effectiveness needs to be determined. These studies were the basis of a new staffing model with the integration of PIPs into the call response system in California.
Asunto(s)
Líneas Directas/organización & administración , Modelos Organizacionales , Pediatría , Intoxicación , Eficiencia Organizacional , Líneas Directas/estadística & datos numéricos , Humanos , San FranciscoRESUMEN
Response to the inhaled bronchodilator, metaproterenol, was evaluated in 28 outpatient infants and young children with cystic fibrosis (CF) (mean age, 16 months) and in 22 normal control children (mean age, 13 months). Lung function was assessed from partial expiratory flow volume curves generated by the rapid compression technique and was quantitated by the maximal expiratory flow at functional residual capacity (VmaxFRC). For the normal control group there was no significant change in VmaxFRC after the aerosol of either normal saline or metaproterenol. At baseline, the group of infants with CF had significantly lower values of VmaxFRC than did the normal control infants (202 versus 273 ml/s, p less than 0.05). The CF group demonstrated no significant change from baseline VmaxFRC after the aerosol of normal saline. However, after metaproterenol the CF group had a significant increase (p less than 0.001) in VmaxFRC, which eliminated the difference in VmaxFRC between the CF and normal control groups (267 versus 276 ml/s). We conclude that infants and young children with CF have increased bronchomotor tone and that bronchoconstriction represents a significant component of the airway obstruction present in patients with CF at this age.
Asunto(s)
Fibrosis Quística/fisiopatología , Metaproterenol/uso terapéutico , Ventilación Pulmonar/efectos de los fármacos , Preescolar , Fibrosis Quística/complicaciones , Femenino , Capacidad Residual Funcional , Humanos , Lactante , Pulmón/fisiopatología , Masculino , Ruidos Respiratorios , Enfermedades Respiratorias/complicaciones , Enfermedades Respiratorias/fisiopatologíaRESUMEN
Oxygen saturation (SaO2) during sleep and pulmonary functions were evaluated in 19 infants with congenital heart disease, aged 6 +/- 4 months, and in 11 normal infants, aged 8 +/- 5 months, to determine whether infants with congenital heart disease have more frequent oxygen desaturation during sleep and, if so, its relationship to underlying pulmonary function. Infants with congenital heart disease were classified as acyanotic (n = 11) or cyanotic (n = 8) on the basis of their aortic SaO2 at the time of cardiac catheterization (greater or less than 90% SaO2). Pulmonary function tests included respiratory rate, functional residual capacity, total respiratory system compliance, and maximal flows at functional residual capacity. Significant differences were found in the values for the lowest SaO2 of each 5-minute epoch (SaO2L) averaged during the entire sleep time (normal 94% +/- 2%, acyanotic 90% +/- 3%, and cyanotic 74% +/- 4%; p less than 0.01). The three groups also differed significantly in frequency distributions of percentage of total sleep time with SaO2L less than 90% (SaO2%T) (normal 10% +/- 17%, acyanotic 36% +/- 34%, and cyanotic 97% +/- 4%; p less than 0.05). Compared with the control group, the acyanotic group had a higher respiratory rate (66 +/- 19 breaths/min vs 35 +/- 6 breaths/min; p less than 0.01), a lower tidal volume (65% +/- 29% predicted vs 105% +/- 18% predicted; p less than 0.01), and a lower total respiratory compliance (59% +/- 18% predicted vs 106% +/- 30% predicted; p less than 0.01). A negative correlation existed between SaO2%T and aortic SaO2 (R2 = 0.64; p less than 0.01). We conclude that oxygen desaturation occurs during sleep in infants with congenital heart disease; the presence of desaturation appears to be related to the initial degree of hypoxemia and the presence of abnormal pulmonary function.
Asunto(s)
Cardiopatías Congénitas/sangre , Oxígeno/sangre , Sueño , Cianosis/sangre , Cianosis/fisiopatología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/fisiopatología , Humanos , Hipoxia/sangre , Hipoxia/fisiopatología , Lactante , Oximetría , Pruebas de Función RespiratoriaRESUMEN
STUDY OBJECTIVE: To estimate the incidence of and risk factors for morbidity due to inhalation of respiratory irritants. DESIGN: Six-month case series of inhalational exposures reported to a poison control center with follow-up, structured interviews of subjects. SETTING: A regional poison control center providing 24-hour telephone consultation to health professionals and the public. PATIENTS: Consecutive sample of 683 inhalation cases, with interviews of 323 subjects. MEASUREMENTS AND MAIN RESULTS: Moderate to severe irritants accounted for 160 (50%) of the inhalational exposures in interviewed subjects. Persistent symptoms lasting 14 days or longer were reported by only 20 (6%) of the subjects. Irritant exposure was a statistically significant risk factor for acute respiratory symptoms (relative risk [RR] = 1.7; 95% confidence interval [Cl], 1.4 to 2.1) but was unrelated to persistent symptoms. Preexisting lung conditions (RR = 2.4; 95% Cl, 1.4 to 4.2) and cigarette smoking (RR = 1.7; 95% Cl, 1.3 to 2.2) were both statistically significant risk factors for persistent symptoms. CONCLUSIONS: Symptomatic inhalational exposures due to irritants are frequent in reports from poison control centers. Residual morbidity was uncommon and did not appear to be statistically related to the degree of irritant exposure. Host-related factors may be better predictors of ongoing morbidity after inhalational exposure.
Asunto(s)
Gases/efectos adversos , Irritantes/efectos adversos , Enfermedades Respiratorias/inducido químicamente , Factores de Edad , Humanos , Entrevistas como Asunto , Enfermedades Pulmonares/complicaciones , Registros Médicos , Morbilidad , Centros de Control de Intoxicaciones , Estudios Prospectivos , Enfermedades Respiratorias/epidemiología , Factores de Riesgo , San Francisco/epidemiología , Índice de Severidad de la Enfermedad , Fumar/efectos adversos , Estados Unidos/epidemiologíaRESUMEN
In a study of occupational illness reported to a regional poison control center and to gauge the center's outreach and services, we did follow-up interviews of 301 case contacts over a 6-month period. We ascertained referral routes, reasons for contacting the poison control center, and awareness of the center's function. For 122 cases a nonphysician was the initial poison control center contact. Of the nonphysician contacts, 41 had already consulted a health care provider and been referred to the poison control center for assistance. Of the 70 persons with exposure, only 21 had been aware before their exposures that poison control center services might include occupational chemical illness consultation. Physicians and nonphysicians expressed similar reasons for contacting the poison control center, with 118 of 301 identifying the need for an exposure hazard risk assessment. These data suggest that although those contacting a poison control center because of occupational illness include a variety of cases, they have many similar service needs.
Asunto(s)
Enfermedades Profesionales/epidemiología , Centros de Control de Intoxicaciones , Derivación y Consulta , Humanos , Centros de Control de Intoxicaciones/normas , Centros de Control de Intoxicaciones/estadística & datos numéricos , Control de Calidad , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
STUDY OBJECTIVE: To evaluate the usefulness of poison control center detection in occupational illness surveillance. DESIGN: Case series of all occupationally related exposures referred for poison control center consultation over 6 months. Follow-up structured interviews were done of exposed persons and health care providers. Cases were traced under established occupational illness reporting programs. SETTING: A regional poison control center. PATIENTS: Consecutive sample of 461 symptomatic occupational exposure cases. After exclusions and losses to follow-up, interview of 301 patients and the treating physician, physician's assistant, or nurse practitioner for the 223 of the patients under direct medical care. MEASUREMENTS AND MAIN RESULTS: One hundred and fifty-five persons (61%; CI, 55% to 67%) had systemic or respiratory illness; 109 (36%; CI, 31% to 41%) had eye or skin conditions. Work practices were associated with exposures more often than technical failure; 118 persons (39%; CI, 33% to 45%) reported lack of respirators or other appropriate personal protective equipment. For 223 persons who received direct medical care, only five treating health care providers (2%; CI, 0.2% to 4%) reported occupational specialization, although occupational care was a regular practice activity for 128 of the health care providers (57%; CI, 51% to 63%). Sixty-seven cases (22%; CI, 17% to 27%) were detected by the Doctor's First Report surveillance program; 97 cases (32%; CI, 27% to 37%) comprised the maximal detection estimated for Occupational Safety and Health Administration surveillance. CONCLUSIONS: Poison control center detection provides a useful surveillance measure for occupational illness. The proportion of case detection failures by established surveillance programs suggests that the incidence of occupational illness in the United States, which is calculated from these incomplete programs, may be three to five times greater than previously estimated.
Asunto(s)
Enfermedades Profesionales/diagnóstico , Centros de Control de Intoxicaciones , Vigilancia de la Población , Adulto , Femenino , Estudios de Seguimiento , Humanos , Entrevistas como Asunto , Masculino , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/prevención & control , Servicios de Salud del Trabajador , San FranciscoRESUMEN
Children with suspected respiratory syncytial virus infection were examined prospectively in a randomized evaluation of standard ribavirin aerosol therapy (6 gm/300 ml water for 18 hours daily) compared with high-dose, short-duration ribavirin aerosol therapy (6 gm/100 ml water given for a period of 2 hours three times a day) by means of an oxygen hood (n = 20) or a ventilator (n = 12). Viral shedding was quantitated daily; clinical observations were recorded daily by 2 physicians aware and one unaware of treatment assignments. Study characteristics evaluated at entry were not significantly different in the high-dose and the standard-dose groups. Viral titers and clinical scores decreased similarly in both groups during the study; pulmonary function test results were also similar at discharge in children not receiving mechanical ventilation. Potential complications related to aerosol therapy were noted in three patients (one hood patient who was receiving standard therapy; two patients with an endotracheal tube in place who were receiving high-dose therapy); substantial crystallization was noted in the tubing of the patients undergoing intubation and receiving high-dose therapy. Environmental sampling revealed that ribavirin was nearly undetectable near patients supported by mechanical ventilation who were receiving either form of therapy, and was significantly decreased on a daily basis in patients without an endotracheal tube who were receiving high-dose therapy compared with those receiving standard therapy. The effects of high-dose, short-duration aerosol ribavirin therapy were similar to those of standard-dose therapy in our study patients and resulted in a decreased release of ribavirin into the room of patients receiving therapy by means of an oxygen hood.