February 2011

Are You Up-to-Speed with AARConnect?
If you’re on the section discussion list, you already know a little about the AARC’s new social networking site, AARConnect, and how it can help you get in touch and stay in touch with fellow members. But the section list is really just one facet of this rich networking environment. So if you’ve yet to explore all that this online community has to offer, click on the link and check out everything from our blogs to resource libraries and more. And be sure to visit your own profile page while you’re there (every AARC member has one on the site) and upload a picture of yourself and provide a little information to let your colleagues know about your background and interests. GET STARTED HERE

Measuring Pulmonary Dead Space During Anesthesia
University of Arizona researchers publishing in this month’s Anesthesia and Analgesia find pulmonary dead space can be accurately assessed during anesthesia using the bellows of a standard anesthesia machine to measure the mixed exhaled carbon dioxide (Peco2) level. The study compared the bellows Peco2 measurement with arterial CO2 (Paco2) measurement in ten patients under general endotracheal anesthesia. The investigators positioned a sampling line inside the ventilator bellows and connected it to a capnometer, then took measurements of Peco2 and Paco2 from an arterial catheter at baseline and after adding 100 mL and 200 mL of dead space to the endotracheal tube. At baseline, the dead space was 265 ± 47 mL. Following the addition of 100 mL of dead space to the endotracheal tube, dead space increased by 110 ± 46 mL. After adding 200 mL, it increased by 158 ± 39 mL. The authors believe this strategy offers a “simple way to detect trends in dead space in ventilated patients.” READ ABSTRACT

Adolescent Idiopathic Scoliosis May Worsen Pulmonary Function
A new study out of the Texas Scottish Rite Hospital shows a significant link between severity of adolescent idiopathic scoliosis (AIS) and pulmonary function test results. The research involved a review of 858 patients in a large multi-center database of surgically treated AIS patients with Lenke 1-4 curves. Results showed 19% of the patients had <65% predicted FEV1 and FVC preoperatively. These patients also had larger MT curves and greater axial rotation than those with predicted PFT values of >65%. The findings were strongest for patients with MT curves >70-80, PT curves that were >30 or structural, or T5-12 kyphosis <10. Axial plane deformity was not associated with PFT impairment, but patients with juvenile-onset deformity, defined as onset under age ten, had greater PFT impairment than those diagnosed in adolescence. These patients also had slightly larger MT curves. PFTs were worse among patients who were braced preoperatively as well. The study appeared in the Jan. 25 Epub edition of Spine. READ ABSTRACT

AHR to Mannitol Captures Eosinophilia in Sputum of COPD Patients
Previous studies have suggested that eosinophilic airway inflammation can be used to tailor anti-inflammatory therapy in patients with COPD. A new study in the Jan. 18 Epub edition of Respiratory Research finds airway hyperresponsiveness (AHR) to inhaled mannitol successfully captures eosinophilia in induced sputum in these patients. The investigation was carried out among 28 patients with GOLD I-II COPD. During two randomized visits, they underwent hypertonic saline-induced sputum and mannitol challenge, with results showing a positive correlation between response-dose-ratio (RDR) to mannitol and eosinophil numbers and level of IL-8 in hypertonic saline-induced sputum. Significant correlations were also seen between RDR and eosinophil numbers, level of ECP, IL-8, and MPO following mannitol challenge. A 60% sensitivity and 100% specificity of RDR for >2.5% eosinophils in mannitol-induced sputum was demonstrated by ROC-curves. The authors conclude, “The high specificity of mannitol challenge suggests that the test is particularly suitable to exclude eosinophilic airways inflammation, which may facilitate individualized treatment in COPD.” READ ABSTRACT

Parental Lung Function May Predict Infant Lung Function
Dutch researchers who compared parental data on lung function with lung function measured before the age of two months in their offspring find parental lung function predicts infant lung function. The study was based on data acquired from 546 infants and their parents. A significant positive relation between the infant’s respiratory compliance and parental FEF25–75%, FEV1, and FVC was noted with univariate linear regression analysis, and a negative significant relation was seen between the infant’s respiratory resistance and parental FEF25–75% and FEV1. The infant’s respiratory time constant and parental lung function did not appear to be related. The significance of the observed relations was reduced after the researchers adjusted for body size, but adjusting for shared environmental factors did not change the findings, leading the investigators to conclude that a genetic mechanism in familial aggregation of lung function is apparent early in life. The study was published in the Jan. 13 Epub edition of the European Respiratory Journal. READ ABSTRACT