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J L Heredia

Publications and source records attributed to J L Heredia.

13 recordsLinked to original sources
PubMed2006

The bronchodilator test in chronic obstructive pulmonary disease: interpretation methods.

The objective of the study was to evaluate the best method for interpreting the bronchodilator test (BDT). Five formulas for expressing the BDT results were analyzed and compared: changes experienced by maximum expiratory volume in 1s (FEV(1)) and forced vital capacity (FVC) measured in milliliters, in percentage with respect to the baseline, in percentage with respect to the predicted, in percentage with respect to the possible, and in standardized residuals. Ninety-eight chronic obstructive pulmonary disease (COPD) patients were submitted to a respiratory function test on two different days. On each occasion three spirometries were conducted: basal, post-placebo and post bronchodilator. As a gold standard, a normality interval was defined using the variability experienced with the placebo between the two days of the study. The best formulas according to their sensitivity, specivity and area under receiver operating characteristic (ROC) curve were the "standardized residuals", with a cut point of .3, and the "percentage with respect to the predicted" with a cut point of 6%.

Aged↗
PubMed2003

[Comparison between automatic and manual analysis in the diagnosis of obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To compare automatic and manual analysis of neurological and respiratory variables obtained with the SomnoStar alpha 4100, a 16-channel polysomnographic system. PATIENTS AND METHOD: Twenty-eight patients suspected of obstructive sleep apnea-hypopnea syndrome were enrolled and given conventional polysomnographic tests. The order of automatic and manual reading of respiratory episodes, sleep stages, and arousals was randomized. We assessed agreement with the intraclass correlation coefficient and plotted standardized differences against standardized means, using the Bland-Altman method. RESULTS: Poor agreement was observed between the 2 types of analysis of sleep stages, especially for REM and deep sleep stages. Agreement was good for apneic episodes among the respiratory variables; however, automatic analysis underestimated hypopneas. If manual analysis is considered the gold standard at the apnea-hypopnea index cut point greater than 10, automatic analysis obtained a sensitivity of 55%, a specificity and positive predictive value of 100%, a negative predictive value of 47%, and an overall diagnostic yield of 67.8%. CONCLUSIONS: The automatic analysis of the SomnoStar 4100 system provides an unsatisfactory reading of sleep stages and respiratory episodes, especially hypopneas.

Female↗
PubMed2001

The bronchodilator test with increasing doses of terbutaline in chronic obstructive pulmonary disease patients.

There is no uniform consensus on the dose of bronchodilator to be used in the bronchodilator test (BDT). The objective of the study was to determine the dose of inhaled terbutaline that can safely achieve a greater number of positive BDT in patients with chronic obstructive pulmonary disease (COPD). The study was prospective and single blinded. One-hundred and fifty patients with stable COPD were included. Their mean (+/-SD) age was 67.4 (8.8) years. Their mean forced expiratory volume in the first second (FEV1) was 1.14 (0.48) l (41% of the predicted value). A baseline spirometry was performed and a second 20 min after the inhalation of placebo. Three consecutive doses of 500 microg of inhaled terbutaline were administered and a new spirometry was performed after each one. A multivariate analysis based on the comparison of the repeated means was performed in order to analyse the spirometric changes achieved after the different doses of bronchodilator. The increase of FEV1 and forced vital capacity (FVC) with the two first doses of terbutaline was statistically significant; the increase of the peak expiratory flow (PEF) was significant after the three doses administered. The number of positive BDT were 40, 47 and 60 after each dose of terbutaline (P=0.004). The higher dose of terbutaline was more useful in identifying patients with significant bronchoreversibility and, moreover, was well tolerated. We suggest that this dose (1500 microg) should be routinely used in performing the BDT.

Aged↗
PubMed1999

Contribution of ipratropium bromide to the bronchodilator test in patients with chronic obstructive pulmonary disease.

The aim of the study was to analyze the bronchodilator test (BDT) response to ipratropium bromide (IB) in patients with chronic obstructive pulmonary disease (COPD) who do not respond to inhaled terbutaline. Sixty patients with stable COPD who showed a negative response to BDT, defined as an increase of less than 160 ml in the forced expiratory volume in the first second (FEV1) after inhaling 1500 microg of terbutaline, were recruited. Each patients randomly received 200 microg of IB or placebo in a single blinded fashion, and a spirometric study was made at 30 and 60 min. The increase in absolute values of FEV1 at 30 and 60 min after IB was significantly higher than after placebo. The means +/- SD were 126 +/- 93 vs. 70 +/- 96 ml at 30 min and 148 +/- 120 vs. 74 +/- 132 ml at 60 min (P=0.01). The BDT was positive in 57% of patients who received IB, considering a positive response as an increase of FEV1 greater than 160 ml (P=0.01). We conclude that the BDT was positive with high doses of IB in more than half of COPD patients who did not respond to terbutaline alone.

Aged↗
PubMed1995

[The perception of improvement in asthma].

BACKGROUND: The capacity of stable asthma patients to recognize the presence of air flow obstruction, treatment improvement and daily variations was studied. METHODS: Placebo and 500 micrograms of inhaled terbutaline for two consecutive days were administered to 39 patients. The subjective impressions were compared with spirometric results. RESULTS: Thirty patients presented obstruction of which 7 reported to be asymptomatic and 9 presented normal spirometry of which 3 reported to be symptomatic. Fifty-four percent (21) did not correctly recognize whether they improved with the medication either of the two days. Eleven patients reported improvement with placebo without significant spirometric changes. Eighteen preferred terbutaline and 5 the placebo while 16 were indifferent out of whom 7 (43%) had improved with only the bronchodilator. The FEV1 difference between the two days was > 10% in 18 patients of which this was not perceived in 10. CONCLUSIONS: Objective controls are necessary for the evaluation and follow up of patients with stable asthma.

Adolescent↗
PubMed1991

[The differential diagnosis between pleural exudates and transudates: the value of cholesterol].

BACKGROUND: The evaluation of a patient with pleural effusion depends on its classification as exudate or transudate. Many criteria have been established but none has a 100% sensitivity and specificity. The aim of the present study was to assess the value of the cholesterol level to differentiate between exudate and transudate and to establish its utility as compared with other differential criteria. METHODS: 104 patients with pleural effusion of well defined etiology, permitting their classification into 56 exudates and 48 transudates, were evaluated. In all, Light's criteria were established and cholesterol values in pleural effusion and serum were measured and compared. RESULTS: Using the lactate dehydrogenase level (LDH) in pleural fluid (PF) and the ratios of LDH and proteins in PF and serum, 100% of exudates and 83% of transudates were correctly classified. A cholesterol level of 40 mg/dl or higher best separated exudates and transudates, with a sensitivity of 96% and a specificity of 92% for exudates. A ratio of 0.3 or higher between cholesterol levels in PF and serum was shown to have a high sensitivity (96%) and lower specificity (85%) for exudates. The highest specificity (92%) was achieved when the protein ratio in PF and serum was combined with PF cholesterol. CONCLUSIONS: The cholesterol level in pleural fluid and the ratio between this value and that in serum are highly useful parameters to differentiate between exudates and transudates.

Cholesterol↗