American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Oct 1998
Comparative StudyEarly predictive factors of survival in the acute respiratory distress syndrome. A multivariate analysis.
To identify the potential impact of novel therapeutic approaches, we studied the early predictive factors of survival at the onset of acute respiratory distress syndrome (ARDS) in a 24-bed medical ICU of an academic tertiary care hospital. Over a 48-mo period, a total of 3,511 adult patients were admitted and 259 mechanically ventilated patients met ARDS criteria, as defined by American-European consensus conference, i.e., bilateral pulmonary infiltrates and PaO2/FIO2 lower than 200 without left atrial hypertension. These patients were randomly included in a developmental sample (177 patients) and a validation sample (82 patients). ⋯ SAPS-II, the severity of the underlying medical conditions, the oxygenation index (mean airway pressure x FIO2 x 100/PaO2), the length of mechanical ventilation prior to ARDS, the mechanism of lung injury, cirrhosis, and occurrence of right ventricular dysfunction were independently associated with an elevated risk of death. Model calibration was very good in the developmental and validation samples (p = 0.84 and p = 0.72, respectively), as was model discrimination (area under the ROC curves of 0.95 and 0.92, respectively). Thus, the prognosis of ARDS seems to be related to the triggering risk factor, the severity of the respiratory illness, and the occurrence of a right ventricle dysfunction, after adjustment for a general severity score.
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Am. J. Respir. Crit. Care Med. · Oct 1998
Comparative StudyImpaired perception of dyspnea in patients with severe asthma. Relation to sputum eosinophils.
Poor dyspnea perception might be a risk factor for developing asthma exacerbations. We investigated whether severe asthmatics with recurrent exacerbations (brittle asthma) have different dyspnea perception and sputum cells compared with equally severe, but stable asthmatics, or patients with mild steroid-naive asthma. Fifteen brittle asthmatics (13 female, median age 28 yr [range, 20 to 47 yr]), 15 matched severe-stable asthmatics (14 female, median age 26 yr [range, 17 to 52 yr]), and 11 mild asthmatics (8 female, median age 25 yr [range, 19 to 43 yr]) underwent inhalation tests with methacholine (MCh), and hypertonic saline combined with sputum induction. ⋯ In the severe asthmatics there was an inverse correlation between sputum eosinophilia and Slope-Borg and Slope-VAS (R = -0.55, p = 0. 002 and R = -0.37, p = 0.049), whereas this correlation was a positive one in the mild asthmatics (R = 0.79, p = 0.012 and R = 0. 67, p = 0.05). In conclusion, patients with severe asthma, particularly those with recurrent exacerbations, have blunted perception of dyspnea, which is related to the degree of sputum eosinophilia. This suggests that increased sputum eosinophilia is an indicator of clinical instabililty, and that eosinophilic airways inflammation might affect dyspnea perception in severe asthma.
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Am. J. Respir. Crit. Care Med. · Oct 1998
Randomized Controlled Trial Comparative Study Clinical TrialRandomized controlled trial of physician-directed versus respiratory therapy consult service-directed respiratory care to adult non-ICU inpatients.
Although current evidence suggests that respiratory care protocols can enhance allocation of respiratory care services while conserving costs, a randomized trial is needed to address shortcomings of available studies. We therefore conducted a randomized controlled trial comparing respiratory care for adult non-ICU inpatients directed by a Respiratory Therapy Consult Service (RTCS) versus respiratory care by managing physicians. Eligible subjects were adult non-ICU inpatients whose physicians had prescribed specific respiratory care services. ⋯ Notably, using both a stringent (S) and a liberal (L) criterion for agreement, RTCS-directed respiratory care demonstrated better agreement with the "standard care plan" (82 +/- 17% [S] and 86 +/- 16% [L]) than did physician-directed respiratory care (64 +/- 21% [S] and 72 +/- 23% [L]) (p < 0.001). Finally, the true cost of respiratory care treatments was slightly lower with RTCS-directed respiratory care (mean, $235.70 versus $255.70/pt, p = 0.61). We conclude that (1) compared with physician-directed respiratory care, the RTCS prescribed a similar number and duration of respiratory care services at a slight savings (that did not achieve statistical significance) and without any increased adverse events; and (2) compared with physician-directed respiratory care, RTCS-directed respiratory care showed greater agreement with Clinical Practice Guideline-based algorithms.
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Am. J. Respir. Crit. Care Med. · Oct 1998
Asthma and natural colds. Inflammatory indices in induced sputum: a feasibility study.
We examined the feasibility of using induced sputum to evaluate the airway inflammatory response to natural acute respiratory virus infections. We recruited eight asthmatics and nine healthy subjects on Day 4 of a cold. Viral infection was confirmed in six of the asthmatics (influenza A or B) and six of the healthy subjects (influenza A, rhinovirus, adenovirus, respiratory syncytial virus, and coronavirus). ⋯ We conclude that induced sputum examination can be used to study the effects of natural colds and influenza on the airways of the lungs. The results also suggest that natural colds, on Day 4, cause neutrophilic lower airway inflammation that is greater in asthmatics than in healthy subjects. The greater inflammatory response in asthmatics may be due to the changes associated with trivial eosinophilia or to the different viruses involved.
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Am. J. Respir. Crit. Care Med. · Oct 1998
Analysis of clinical methods used to evaluate dyspnea in patients with chronic obstructive pulmonary disease.
When dyspnea must be assessed clinically, there are three methods of assessment: the measurement of dyspnea with activities of daily living using clinical dyspnea ratings such as the modified Medical Research Council (MRC), the Baseline Dyspnea Index (BDI), and the Oxygen Cost Diagram (OCD); the measurement of dyspnea during exercise using the Borg scale; to assess the influence of dyspnea on health-related quality of life (HRQoL) using disease-specific questionnaires such as the St. George's Respiratory Questionnaire (SGRQ) and the Chronic Respiratory Disease Questionnaire (CRQ). The purpose of the present cross-sectional study was to clarify relationships between dyspnea ratings and HRQoL questionnaires by applying factor analysis. ⋯ The MRC, BDI, OCD, and Activity in the SGRQ, and Dyspnea in the CRQ demonstrated the same pattern of correlation with physiologic data, and they had significant relationships with FEV1 (correlation coefficients [Rs] = 0.31 to 0. 48) and maximal oxygen uptake (Rs = 0.46 to 0.60). Disease-specific HRQoL questionnaires, the SGRQ and the CRQ, which contain a specific dimension for evaluating dyspnea, may be substituted for clinical dyspnea ratings in a cross-sectional assessment. Dyspnea rating at the end of exercise may provide further information regarding dyspnea.