American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Jan 1999
Spirometric reference values from a sample of the general U.S. population.
Spirometric reference values for Caucasians, African-Americans, and Mexican-Americans 8 to 80 yr of age were developed from 7,429 asymptomatic, lifelong nonsmoking participants in the third National Health and Nutrition Examination Survey (NHANES III). Spirometry examinations followed the 1987 American Thoracic Society recommendations, and the quality of the data was continuously monitored and maintained. Caucasian subjects had higher mean FVC and FEV1 values than did Mexican-American and African-American subjects across the entire age range. ⋯ These differences may be partially due to differences in body build: observed Mexican-Americans were shorter than Caucasian subjects of the same age, and African-Americans on average have a smaller trunk:leg ratio than do Caucasians. Reference values and lower limits of normal were derived using a piecewise polynomial model with age and height as predictors. These reference values encompass a wide age range for three race/ethnic groups and should prove useful for diagnostic and research purposes.
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Am. J. Respir. Crit. Care Med. · Jan 1999
Randomized Controlled Trial Clinical TrialIntrapleural urokinase versus normal saline in the treatment of complicated parapneumonic effusions and empyema. A randomized, double-blind study.
Intrapleural administration of fibrinolytic agents has been shown to be effective and safe in the treatment of loculated parapneumonic pleural effusions. However, controlled studies of the possible role of the activity of urokinase (UK) through the volume effect are lacking. We therefore investigated the hypothesis that UK is effective through the lysis of pleural adhesions and not through the volume effect. ⋯ Pleural fluid drainage was complete in 13 (86.5%) patients in the UK group (two patients were treated through video-assisted thoracoscopy) but in only four (25%) in the control group. Twelve patients in the control group were subsequently treated with UK and six of them had complete drainage; the remaining six patients had complete drainage after video-assisted thoracoscopy. Our results suggest that UK is effective in the treatment of loculated pleural effusions through the lysis of pleural adhesions and not through the volume effect.
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Am. J. Respir. Crit. Care Med. · Jan 1999
Bacterial colonization patterns in mechanically ventilated patients with traumatic and medical head injury. Incidence, risk factors, and association with ventilator-associated pneumonia.
We prospectively evaluated the relation of upper airway, lower airway, and gastric colonization patterns with the development of pneumonia and its etiology in 48 patients with surgical (n = 25) and medical (n = 23) head injury. Initial colonization was assessed by cultures of nasal and pharyngeal swabs, tracheobronchial aspirates, gastric juice, and bronchoscopically retrieved protected specimen brush. Follow-up colonization was determined until the end points extubation, suspected ventilator-associated pneumonia (VAP), or death. ⋯ We conclude that patients with head injury are colonized in the airways mainly by Group I pathogens early in the evolution of illness. The upper airways represent the main reservoir for subsequent lower airway colonization with Group I pathogens. Previous (short-term) antibiotic treatment is protective against initial tracheobronchial colonization with Group I pathogens, but it represents a risk factor for subsequent lower airway colonization by Group II pathogens.
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Am. J. Respir. Crit. Care Med. · Jan 1999
Risk factors for pulmonary mycobacterial disease in South African gold miners. A case-control study.
Pulmonary mycobacterial disease is common in miners. Risk factors for nontuberculous pulmonary mycobacterial (NTM) disease and tuberculosis (TB) in gold miners were identified in a retrospective case-control study that included 206 NTM patients and 381 TB patients of known human immunodeficiency virus (HIV) status diagnosed between 1993 and 1996. A total of 180 HIV-tested trauma/surgical inpatients were selected as control patients. ⋯ Previous TB (OR 9.6), premorbid focal radiological scarring (OR 7.4) and a dusty job at diagnosis (OR 2.4) were additional significant risk factors for NTM disease. These findings suggest that the historically high incidence of NTM disease in miners is largely attributable to chronic chest disease from silica dust inhalation and prior TB. HIV infection has recently become an additional risk factor for mycobacterial disease in miners and is likely to become increasingly important as the HIV epidemic progresses.
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Am. J. Respir. Crit. Care Med. · Jan 1999
Pharyngeal critical pressure in patients with obstructive sleep apnea syndrome. Clinical implications.
Current evidence suggests that patients with obstructive sleep apnea (OSA) may have greater pharyngeal critical pressure (Pcrit), which reflects the increase in upper airway collapsibility. The contribution of Pcrit to the severity of OSA and to the efficacious continuous positive pressure (nCPAPeff) therapy has never been extensively described and no data are available about the interaction of Pcrit, age, and anthropometric variables. To determine the relationship between Pcrit, severity of the disease, nCPAPeff, and anthropometric variables we measured Pcrit in a group of 106 patients with OSA. ⋯ In patients for whom the measure of respiratory effort was obtained, 42% of the variance in nCPAPeff was explained by RPes (33%) and BMI. From these results we conclude that Pcrit alone does not yield a diagnostically accurate estimation of OSA severity and nCPAPeff. Although individual collapsibility may predispose to pharyngeal collapse, upper airway occlusion may require the combination of several factors, including obesity, upper airway structure, and abnormalities in muscle control.