August 2008

Last Chance to Nominate a Section Member for Specialty Practitioner of the Year
Nominations for this year’s Diagnostics Specialty Practitioner of the Year are due by August 31. Please consider nominating a fellow section member for this important award. You can find the nomination form on the SECTION WEB SITE.

Dosimeter vs. Tidal Breathing Method: Where the Differences Lie
Are the differences in methacholine PC(20) values between the dosimeter (DM) and tidal breathing methods (TBM) really due to differences in the dose of agonist delivered to the mouth? No, report Spanish investigators who compared the two methods in 27 patients suspected of having asthma. Using a DM that was modified to deliver the same volume of aerosol as the TBM, they found:

• The DM PC(20) was significantly higher than the TBM PC(20), with geometric mean (95% CI) values of 4.03 (1.86 - 8.78 mg/ml) and 2.19 (1.32 - 3.64 mg/ml, P = 0.04), respectively.
• The mean difference in the PC(20) value detected with each method was similar in subjects with TBM PC(20) values >/=2 mg/ml (0.77 doubling concentrations) and in those with PC(20) values<2 mg/ml (0.96 doubling concentrations, P = 0.83).

The authors conclude, “These results suggest that the discordant PC(20) values obtained with the two methods are not due to differences in the dose of agonist delivered to the mouth.” The study appeared in the July 14 Epub edition of CHEST. READ ABSTRACT

Standards Needed for Exercise Testing in Cancer Trials
The reporting of exercise testing methods and data in clinical trials involving adults with cancer is lacking, conclude Duke University researchers publishing in the August issue of Lancet Oncology. They reviewed previous studies incorporating exercise testing as an objective assessment of cardiorespiratory fitness in cancer patients, finding the conduct of the tests falls short of American Thoracic Society/American College of Chest Physicians recommendations for exercise testing. “The adoption of consistent, formal standards for methods and data reporting in exercise testing is needed to ensure high-quality research in clinical oncology,” write the authors. The paper goes on to provide recommendations for exercise testing in this setting. READ ABSTRACT

BAL Proteins Differ in ARDS
Washington State investigators have identified important differences between the proteins found in the bronchoalveolar lavage (BAL) fluid of patients with ARDS and healthy volunteers. They compared BAL proteins on days 1, 3, and 7 of ARDS with those seen in the controls using two dimensional difference gel electrophoresis, with proteomics and protein network analyses. The researchers found the differences were due to the enrichment of proteins involved in inflammation, infection, and injury. “The results provide new insights about protein networks in injured lungs, and identify novel mediators that are likely to be involved in the pathogenesis and progression of acute lung injury,” they write. The study was published in the July 24 Epub edition of the American Journal of Respiratory and Critical Care Medicine. READ ABSTRACT

Walking Tests Useful for Assessing COPD Response to Formoterol
A new study out of Italy suggests walking tests have an important role to play in evaluating patient outcomes for COPD patients on bronchodilators and also indicates the 6 minute walk test (6-MWT) may be a better instrument for assessing exercise response than the 12 minute walk test (12-MWT). Researchers conducted a crossover study involving patients who had undergone 5 days of treatment with formoterol. The drug induced a progressively significant increase in pre-drug FEV1 and IC and significant changes in these parameters 2 hours after inhalation. The distance walked increased by 53.6m on the 6-MWT and by 59.9m on 12-MWT. However, while a significant change in Borg score for dyspnea was seen after the 6-MWT when compared with the pre-treatment values, the drug significantly changed dyspnea induced by the 12-MWT only after the first dose. The investigation was published in the July 11 Epub edition of Respiratory Medicine. READ ABSTRACT