September 2013
Register Now for AARC Congress 2013
The AARC Congress will head to Anaheim, CA, Nov. 16-19, and the agenda is packed with presentations that will be of special interest to respiratory therapists practicing in the diagnostic area. So take a few moments to review the program and then make your plans to attend. VIEW PROGRAM
Billing Issue Addressed
A recent article in the ATS Coding and Billing Quarterly addressed a billing question that may arise in your pulmonary function laboratory. Specifically, can labs bill for lung volume determination using only alveolar volume obtained from the DLCO maneuver? According to the ATS, the answer is no. This calculation may not be described using the 94727 code. That code specifically states that a nitrogen washout or helium dilution testing technique must be used in order to bill using the code.
“Fast” is Better than “Far”
Instructing patients to walk “as far as possible” when initiating a six minute walk test might not be the best tactic, report Virginia investigators publishing ahead of print in CHEST on Aug. 22. They enrolled 24 patients in a study in which they randomly used four different set of instructions when beginning the six minute walk test: walk “as far as possible,” “as fast as possible,” “at your normal pace,” or “at a leisurely pace.” The goal was to see which set of instructions would elicit the best outcomes. Results showed patients walked the farthest when instructed to walk “as fast as possible.” Patients with pulmonary arterial hypertension walked 41.5 meters further, patients with idiopathic pulmonary fibrosis walked 66.5 meters further, and those with other interstitial lung diseases walked 53 meters further. The authors conclude, “Patients do not walk as far as they are able with the standard ATS instruction for 6MWT. Changing the wording from ‘far’ to ‘fast’ may facilitate a better effort and greater distance during the test.” READ ABSTRACT
Patients Often Take Drugs that Interfere with PFTs
Australian researchers publishing ahead of print in the International Journal of Chronic Obstructive Pulmonary Disease find many patients undergoing pulmonary function testing may have taken drugs prior to testing that could affect the results. They arrived at that conclusion after auditing 100 patients presenting to a PFT laboratory for testing. All were questioned about their recent drug use. Among the group, 63 were prescribed drugs known to interfere with PFTs, and 36 had consumed at least one of these drugs during the withholding period. Beta blockers with or without beta agonists were consumed by 18. Overall, 65 of the patients reported not receiving any advice about withholding certain drugs before they came in for testing. Only ten patients recalled receiving any instruction on drugs from their health care providers. “Subjects presenting for PFT are infrequently advised to withhold drugs that may affect FEV1 reversibility, and consequently, often take such drugs close to the time of the test,” write the authors. “Therefore, it is likely that the increase in FEV1 is frequently affected by interference from drugs and this might impact on diagnosis and/or treatment options.” READ ABSTRACT
QCT Measures May Be Useful
Quantitative CT (QCT) measurements may be useful in assessing disease severity in smokers with and without COPD, report National Jewish of Health investigators. They evaluated inspiratory and expiratory CT scans of 4062 subjects taking part in the Genetic Epidemiology of COPD Study. In the study, emphysema was defined as the percentage of low-attenuation areas ≤ -950 HU on inspiratory CT (LAA-950I). Air trapping, defined as the percentage of low-attenuation areas ≤ -856 HU on expiratory CT (LAA-856E), and the inner diameter, inner and outer areas, wall area, airway wall thickness, and square root of the wall area of a hypothetical airway of 10-mm internal perimeter of segmental and subsegmental airways served as measures as well. Among the results:
- QCT measurements of low-attenuation areas correlate strongly and significantly with spirometry.
- The correlation between LAA-856E and FEV1 and the ratio of FEV1 to FVC is stronger than the correlation between LAA-950I and FEV1 and FEV1/FVC.
- Inspiratory and expiratory volume changes decreased with increasing disease severity, as measured by the GOLD staging system.
- When airway variables were included with low-attenuation area measures in a multiple regression model, the model accounted for a statistically greater proportion of variation in FEV1 and FEV1/FVC.
- Airway measurements alone are less correlated with spirometric measures of FEV1 and FEV1/FVC.
The study appears in this month’s American Journal of Roentgenology. READ ABSTRACT
