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991.
Importance of the field: Chronic endobronchial infection in cystic fibrosis (CF) leads to progressive lung function loss and respiratory failure. Most adult CF patients are infected with Pseudomonas aeruginosa, an important predictor of mortality. Suppressing chronic P. aeruginosa infection with inhaled antibiotics is standard of care for CF patients.

Areas covered in this review: This review describes the development (2003 – 2010) of aztreonam lysine 75 mg powder and solvent for nebulizer solution (AZLI; Cayston®), an aerosolized formulation of the monobactam antibiotic aztreonam.

What the reader will gain: AZLI was studied in patients with CF and chronic P. aeruginosa airway infection. In placebo-controlled trials, AZLI improved respiratory symptoms, increased forced expiratory volume in 1 sec (FEV1), decreased sputum P. aeruginosa density, and was well tolerated. An open-label follow-on trial of nine ‘on/off’ courses showed that AZLI was safe and the effect durable with repeated administration. AZLI was recently approved for use in CF patients in Australia and the USA, and conditionally approved in Canada and the European Union. AZLI is given three times daily for 28 days (2 – 3 min/dose), followed by 28 days off-drug. AZLI is used only with the Altera Nebulizer System?, which provides appropriate particle size and small airway deposition, and has excellent portability.

Take home message: AZLI is a new therapy that is safe and effectively improves respiratory symptoms and FEV1 in patients with CF.  相似文献   
992.

Background

A pulmonary hypertensive crisis (PHC) can be a life-threatening condition. We established a PHC model by exposing rats with monocrotaline (MCT)-induced pulmonary hypertension to acute hypoxia, and investigated the effects of vasopressin, phenylephrine, and norepinephrine on the PHC.

Methods

Four weeks after MCT 60 mg kg?1 administration i.v., right ventricular systolic pressure (RVSP), systolic BP (SBP), mean BP (MBP), cardiac index (CI), and pulmonary vascular resistance index (PVRI) were measured. PHC defined as an RVSP exceeding or equal to SBP was induced by changing the fraction of inspiratory oxygen to 0.1. Rats were subsequently treated by vasopressin, phenylephrine, or norepinephrine, followed by assessment of systemic haemodynamics, isometric tension of femoral and pulmonary arteries, cardiac function, blood gas composition, and survival.

Results

PHC was associated with increased RV dilatation and paradoxical septal motion. Vasopressin increased MBP [mean (standard error)] from 52.6 (3.8) to 125.0 (8.9) mm Hg and CI from 25.4 (2.3) to 40.6 (1.8) ml min?1 100 g?1 while decreasing PVRI. Vasopressin also improved RV dilatation, oxygenation, and survival in PHC. In contrast, phenylephrine increased MBP from 54.8 (2.3) to 96.8 (3.2) mm Hg without improving cardiac pump function. Norepinephrine did not alter MBP. Vasopressin contracted femoral but not pulmonary arteries, whereas phenylephrine contracted both arterial beds. Hence, improvements with vasopressin in PHC might be associated with decreased PVRI and selective systemic vasoconstriction.

Conclusions

In this rat model of a PHC, vasopressin, but not phenylephrine or norepinephrine, resulted in better haemodynamic and vascular recovery.  相似文献   
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ObjectivesDynamic hyperinflation (DH) significantly affects dyspnea and intolerance to exercise in patients with chronic obstructive pulmonary disease (COPD). Quantitative computed tomography (QCT) of the chest is the modality of choice for quantification of the extent of anatomical lung damage in patients with COPD. The purpose of this article is to assess the effects of DH on QCT measurements.MethodsThe study sample comprised patients with Global initiative for Chronic Obstructive Lung Disease (GOLD) stages III and IV COPD referred for chest CT. We examined differences in total lung volume (TLV), emphysema volume (EV), and emphysema index (EI) determined by QCT before and after DH induction by metronome-paced tachypnea (MPT). Initial (resting) and post-MPT CT examinations were performed with the same parameters.ResultsImages from 66 CT scans (33 patients) were evaluated. EV and EI, but not TLV, increased significantly (p < 0.0001) after DH induction.ConclusionQCT showed significant increases in EV and EI after MPT-induced DH in patients with GOLD stages III and IV COPD. For longitudinal assessment of patients with COPD using QCT, we recommend the application of a pre-examination rest period, as DH could mimic disease progression. QCT studies of the effects of DH-preventive therapy before exercise could expand our knowledge of effective measures to delay DH-related progression of COPD.  相似文献   
995.
Chronic obstructive pulmonary disease (COPD) is characterized by chronic respiratory symptoms and airflow limitation, resulting from abnormalities in the airway and/or damage to the alveoli. Primary care physicians manage the healthcare of a large proportion of patients with COPD. In addition to determining the most appropriate medication regimen, which usually includes inhaled bronchodilators with or without inhaled corticosteroids, physicians are charged with optimizing inhalation device selection to facilitate effective drug delivery and patient adherence. The large variety of inhalation devices currently available present numerous challenges for physicians that include: (1) gaining knowledge of and proficiency with operating different device classes; (2) identifying the most appropriate inhalation device for the patient; and (3) providing the necessary education and training for patients on device use. This review provides an overview of the inhalation device types currently available in the United States for delivery of COPD medications, including information on their successful operation and respective advantages and disadvantages, factors to consider in matching a device to an individual patient, the need for device training for patients and physicians, and guidance for improving treatment adherence. Finally, the review will discuss established and novel tools and technology that may aid physicians in improving education and promoting better adherence to therapy.  相似文献   
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A patient with eroded tricuspid and pulmonic valves, who eventually developed elevated right atrial and systemic venous pressure that led to hepatic cirrhosis and recurrent pleural effusion, is presented. The complex issues involved over a long period in this patient, who ultimately required combined heart and liver transplant, are discussed.  相似文献   
999.
Aorta to pulmonary artery fistula is an uncommon and potentially fatal condition. This case is of a 48‐year‐old Caucasian male with congestive heart failure and multiple aortic valve replacement surgeries who presented with an acquired ascending aortic aneurysm to pulmonary artery fistula diagnosed using two‐dimensional transthoracic echocardiography via nonstandard imaging windows. Three‐dimensional transthoracic echocardiography using live/real time three‐dimensional color Doppler was used to assess the size of the opening of the fistula, providing additional value. This patient was surgically managed and is doing well 8 months postoperation.  相似文献   
1000.
With emphysema now ranking second among causes of disability in men past 40, Dr. Haas believes that careful reappraisal of the criteria for hospitalization in this disease is indicated. Critical to this reappraisal, he maintains, is recognition that many patients now “written oil'” as hopeless cripples may be returned to “the dignity of economic and social independence.”  相似文献   
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