Do airway metallic stents for benign lesions confer too costly a benefit?

<p>Abstract</p> <p>Background</p> <p>The use of self-expanding metallic stents (SEMAS) in the treatment benign airway obstruction is controversial.</p> <p>Methods</p> <p>To evaluate the safety and efficacy of SEMAS for this indication, we conducted a 10-year retrospective review at our tertiary medical centre.</p> <p>Results</p> <p>Using flexible bronchoscopy, 82 SEMAS (67% Ultraflex, 33% Wallstent) were placed in 35 patients with inoperable lesions, many with significant medical comorbidities (88%). 68% of stents were tracheal, and 83% of patients showed immediate symptomatic improvement. Reversible complications developed in 9% of patients within 24 hrs of stent placement. Late complications (>24 hrs) occurred in 77% of patients, of which 37% were clinically significant or required an interventional procedure. These were mainly due to stent migration (12.2%), fracture (19.5%), or obstructive granulomas (24.4%). The overall granuloma rate of 57% was higher at tracheal sites (59%) than bronchial ones (34%), but not significantly different between Ultraflex and Wallstents. Nevertheless, Wallstents were associated with higher rates of bleeding (5% vs. 30%, p = 0.005) and migration (7% vs. 26%, p = 0.026). Of 10 SEMAS removed using flexible bronchoscopy, only one was associated with incomplete removal of fractured stent wire. Median survival was 3.6 ± 2.7 years.</p> <p>Conclusion</p> <p>Ill patients with inoperable lesions may be considered for treatment with SEMAS.</p

Analysis of volatile compounds in exhaled breath condensate in patients with severe pulmonary arterial hypertension.

BackgroundAn important challenge to pulmonary arterial hypertension (PAH) diagnosis and treatment is early detection of occult pulmonary vascular pathology. Symptoms are frequently confused with other disease entities that lead to inappropriate interventions and allow for progression to advanced states of disease. There is a significant need to develop new markers for early disease detection and management of PAH.Methodolgy and findingsExhaled breath condensate (EBC) samples were compared from 30 age-matched normal healthy individuals and 27 New York Heart Association functional class III and IV idiopathic pulmonary arterial hypertenion (IPAH) patients, a subgroup of PAH. Volatile organic compounds (VOC) in EBC samples were analyzed using gas chromatography/mass spectrometry (GC/MS). Individual peaks in GC profiles were identified in both groups and correlated with pulmonary hemodynamic and clinical endpoints in the IPAH group. Additionally, GC/MS data were analyzed using autoregression followed by partial least squares regression (AR/PLSR) analysis to discriminate between the IPAH and control groups. After correcting for medicaitons, there were 62 unique compounds in the control group, 32 unique compounds in the IPAH group, and 14 in-common compounds between groups. Peak-by-peak analysis of GC profiles of IPAH group EBC samples identified 6 compounds significantly correlated with pulmonary hemodynamic variables important in IPAH diagnosis. AR/PLSR analysis of GC/MS data resulted in a distinct and identifiable metabolic signature for IPAH patients.ConclusionsThese findings indicate the utility of EBC VOC analysis to discriminate between severe IPAH and a healthy population; additionally, we identified potential novel biomarkers that correlated with IPAH pulmonary hemodynamic variables that may be important in screening for less severe forms IPAH

Exhaled volatile organic compounds in individuals with a history of high altitude pulmonary edema and varying hypoxia-induced responses

With ascent to altitude, certain individuals are susceptible to high altitude pulmonary edema (HAPE), which in turn can cause disability and even death. The ability to identify individuals at risk of HAPE prior to ascent is poor. The present study examined the profile of volatile organic compounds (VOC) in exhaled breath condensate (EBC) and pulmonary artery systolic pressures (PASP) before and after exposure to normobaric hypoxia (12% O ) in healthy males with and without a history of HAPE (Hx HAPE, n = 5; Control, n = 11). In addition, hypoxic ventilatory response (HVR), and PASP response to normoxic exercise were also measured. Auto-regression/partial least square regression of whole gas chromatography/mass spectrometry (GC/MS) data and binary logistic regression (BLR) of individual GC peaks and physiologic parameters resulted in models that separate individual subjects into their groups with variable success. The result of BLR analysis highlights HVR, PASP response to hypoxia and the amount of benzyl alcohol and dimethylbenzaldehyde dimethyl in expired breath as markers of HAPE history. These findings indicate the utility of EBC VOC analysis to discriminate between individuals with and without a history of HAPE and identified potential novel biomarkers that correlated with physiological responses to hypoxia.

Long-term study of oral treprostinil to treat pulmonary arterial hypertension. dosing, tolerability, and pharmacokinetics

Oral treprostinil may be an option for low- and intermediate-risk patients with pulmonary arterial hypertension, a rare lung vascular disease. This open-label extension study collected data on participants who completed previously reported, placebo- controlled oral treprostinil studies. Eligible participants had completed the prospective parent studies and took increasing doses of oral treprostinil twice daily; some later transitioned to three times daily dosing. Investigators measured 6-minute walk distance at Month 12 as the sole efficacy measure but collected adverse events throughout the study. A single center measured pharmaco- kinetics in 13 subjects who changed dosing from twice daily to three times daily. Eight hundred and ninety-four participants enrolled and 71% completed one year of therapy, with a median total daily dose of 7 mg and a median 6-minute walk distance increase of 22 m (interquartile range, 14 to 67 m). Subjects achieving higher doses had larger increases in 6-minute walk distance; 42% of participants completed three years of therapy. Adverse events were typical for prostacyclin class therapy, but prostacyclin- type adverse events may have been better tolerated with three times daily dosing in 105 participants. In 13 participants transitioned to three times daily dosing with pharmacokinetic measurements before and after, trough drug levels were higher with three times daily dosing. Oral treprostinil is associated with modest but durable, dose-responsive effects on exercise tolerance for those who remained on therapy at one year in this prospective, uncontrolled study. Three times daily dosing was associated with higher trough levels and better tolerability. The recently completed Freedom-EV study will provide further insights into the utility of oral treprostini