ATS / ERS guidelines recommend using % predicted FEV1 as the metric to define severity of obstructive, restrictive, and mixed ventilatory disorders. The main driver: FEV1 is the most robust variable as an overall measure of health (epidemiologically speaking). Critics charge that this overestimates severity of obstruction when restriction is also present, causing confusion, misdiagnosis, [... read more]
Part 1 of Levine et al’s excellent review on toxicology in the ICU. Some of their helpful recommendations/reminders: False positive UDS are common for tricyclics (diphenhydramine/Benadryl, carbamazepine, quetiapine/Seroquel), as are false negatives for benzodiazepines (lorazepam/Ativan, alprazolam/Xanax). The osmolal gap is elevated in ethanol, methanol, ethylene glycol, isopropanol, propylene glycol toxicity, but also in shock and [... read more]
Enriquez et al analyzed data from the NHLBI Dynamic Registry, comparing 860 people with COPD to 10,048 without who underwent percutaneous coronary intervention between 1999-2006. Their main findings: COPD patients were sicker and had worse outcomes. Demographically, they had a higher rate of diabetes, slightly more lesions (3.2 vs. 3.0), and slightly lower ejection fractions. Only [... read more]
Wisnivesky et al crunched through the SEER data on 3,399 people who underwent resection for N1 non-small cell lung cancer. They found that the number of cancerous lymph nodes predicted survival: 1 positive N1 lymph node: 8.8 years mean lung cancer-specific survival 2-3 positive N1 lymph nodes: 8.2 years 4-8 positive N1 lymph nodes: 6.0 [... read more]
Drager LF et al. Obstructive Sleep Apnea: An Emerging Risk Factor for Atherosclerosis. CHEST 2011;140:534-542. OSA and CAD review.
Self-reported adherence is usually overestimated. Most people prescribed chronic daily medication take it ~60% of the time, but say/believe they take it 90% of the time. People with cystic fibrosis are instructed to spend more than an hour a day sitting through up to 7 nebulizer treatments. Daniels et al used a smart nebulizer machine [... read more]
Accountability for Medical Error: Moving Beyond Blame to Advocacy. CHEST 2011;140:519-526. Bell et al’s great essay on the dysfunctional mechanics and culture of liability / safety / blame surrounding medical errors in hospitals and our medical care system in general. They propose steps toward “collective accountability,” e.g., we MDs should sit on hospital safety committees. But [... read more]
Do we need to worry about pre-existing heparin-induced thrombocytopenia antibodies in people admitted with pulmonary embolism / deep venous thrombosis? Or can we keep happily slinging heparin at first sight? Warkentin et al analyze data from the Matisse VTE studies, which enrolled 3,994 patients with DVT or PE. All had ELISA HIT antibodies collected at [... read more]
Hersh et al analyzed spirometry and patient-reported data on family history from the COPDGene study, comparing 821 people with COPD to 776 smoking controls. Subject-recalled parental history of COPD had an odds ratio of 1.7 for COPD in the subject. The population attributable risk from family history for COPD was 18.6%. They acknowledge the vulnerability [... read more]
Mavros et al did the heavy lifting required to review 998 studies relating in some way to atelectasis and postoperative fever. They felt only 8 of those studies deserved analysis (990 were excluded either for not reporting sufficient data, or not focusing on the question at hand). One study reported an association between atelectasis and [... read more]
Bronchiolitis Obliterans Syndrome: The Final Frontier. No, it’s not the new Star Trek movie featuring a breathless William Shatner. It’s Todd JL, Palmer SM’s review on BOS, the lung transplantation scourge, in CHEST 2011;140:502-508.
Low physical activity is associated with mortality in COPD, but until now, only on the basis of self-reported activity levels. Waschki et al prospectively followed 170 people (~75% men, ~65 years old) with stable COPD for 48 months. Besides spirometry (mean FEV1 56% predicted), the investigators also collected other data expected to be predictive, including [... read more]
Kuniyoshi et al prospectively observed people admitted to Mayo for myocardial infarction, performing polysomnography and measuring flow-mediated dilation in their brachial arteries. A whopping 69% (45 of 64) were found to have obstructive sleep apnea. Those with moderate to severe OSA had poorer arterial responsiveness, a surrogate marker for subsequent cardiovascular risk, compared to people [... read more]
Brown et al report that 21% of patients in the REVEAL registry were diagnosed with IPAH >2 years after the onset of symptoms. Younger patients, and those picking up a diagnosis of obstructive lung disease or sleep apnea along the way, were more likely to have a delay in diagnosis. CHEST 2011;140:19-26.
Lore has it that pure-right sided heart disease in pulmonary arterial hypertension doesn’t cause pleural effusions. Luo et al report here that it does, in 35 of 89 people (39%) with connective-tissue disease-related PAH. (29 of the 35 had no other discernible cause for the effusion.) CHEST 2011;140:42-47. Their group previously reported that people with [... read more]
The Research Agenda in ICU Telemedicine: A Statement From the Critical Care Societies Collaborative. Kahn JM et al. CHEST 2011;140:230-238.
A retrospective review of 521 patients in one Virginia center from 2000-2009, by Nathan SD et al. CHEST 2011;140:221-229
Yao et al report a meta-analysis of 8 studies (n=728) measured hydrogen peroxide in exhaled breath condensate in asthmatics. Overall, concentration of H2O2 did distinguish asthmatics from non-asthmatics, and H2O2 levels correlated with worsening asthma control and with declining FEV1. CHEST 2011;140:108-116.
Glycemic Control in the ICU. Egi M et al. CHEST 2011;140:212-220. Endocrine, hyperglycemia, review.
Chapman et al extended their 6-month Phase III trial for once-daily long-acting beta agonist indacaterol for another 6 months. FEV1 improvements of 170 mL, reduced albuterol use of 1 puff / day, and slight absolute decreases in exacerbation rates were all preserved, without evidence of tolerance or increased adverse events. The drug made about 24% [... read more]