Current Respiratory Medicine Reviews - Volume 2, Issue 4, 2006

The pulmonary circulation is normally a low-pressure, low resistance circuit due to its large cross-sectional area and high capacitance. Pulmonary hypertension is defined as a mean pulmonary arterial pressure >25 mm Hg at rest or 30 mm Hg at exercise at catheterization. Chronic thromboembolic pulmonary disease is a cause of pulmonary hypertension [1-9]. The condition is defined by absence of thrombus resolu Read More

Due to their long survival and high cumulative corticosteroid dose, COPD patients become susceptible to unusual microorganisms that commonly affect immunosuppressed patients. Among them, fungi such as Aspergillus and Pneumocystis jiroveci and a bacterium Nocardia, a slow growing Gram-positive and acid-fast staining filamentous branching rod, have been reported in the last decade. Aspergillus can affect immunoco Read More

Cyclic GMP-dependent protein kinase (PKG) plays a central role in the responses of the pulmonary vasculature to nitric oxide, nitrovasodilators, and natriuretic peptides. In mammalian cells, PKG is present in two forms, PKG I and PKG II, and the type I isoform is the primary enzyme involved in cGMP-dependent regulation of cardiovascular function. PKG can mediate vasodilation by lowering cytosolic Ca2+ levels by stimulating c Read More

Our understanding of mechanisms involved in worsening of airway function during sleep is incomplete. Therefore, this work is aimed to link central neuronal structures alternating wakefulness and sleep with the neuronal network regulating the activity of airway-related vagal preganglionic neurons (AVPNs). Based on knowledge derived from previous studies, we build a dynamic model in which AVPNs transmit excitatory sign Read More

In the last three decades studies of respiration have embarked on a new phase eliciting exciting new areas of investigation. At this juncture we are happy to contribute a brief article honoring NS Cherniack. During this transition period, features like oxygen sensing in the carotid body in the context of whole body has emerged. ATP has been proposed as a key mediator of peripheral chemosensory transduction at sea level. W Read More

The structure of several respiratory models are reviewed and the physiological foundations of salient features are explained. The models reviewed include an early model of Cheyne-Stokes breathing, the gas stores of the body following alterations in ventilation, sleep apnea considered as instability in the respiratory control system, a neurochemical model describing effects of neural drives on breathing in respiratory contro Read More

Chronic renal failure may be associated with a wide spectrum of respiratory disorders, varying from relatively minor derangements in pulmonary function testing, to frank pulmonary edema. Although complications like uremic lung are becoming increasingly rare in these patients with timely initiation of dialysis, dialysis itself can also exert a transient deleterious influence on gas exchange. Moreover, patients with chronic renal Read More

The Global Initiative for Chronic Obstructive Lung Disease guidelines stated that COPD is a disease of airflow limitation that is associated with abnormal inflammatory response. Targeting inflammation and improving airflow is a central goal to treat this disease. Corticosteroids are currently the most popular anti-inflammatory agents for obstructive airway disease. Several long-acting bronchodilators are available to improve Read More

Carotid bodies are the sensory organs for detecting systemic hypoxia and the ensuing reflexes prevent the development of tissue/cellular hypoxia. Reflexes arising from carotid body play important roles in pathophysiology involving chronic hypoxia. The purpose of this article is to: a) present a brief overview of the current concepts of O2 sensing by the carotid body, and b) how chronic intermittent hypoxia (CIH) such as that see Read More

Approximately 4% of all individuals that develop pulmonary embolism will go on to have chronic thromboembolic pulmonary hypertension (CTEPH). Patients with severe CTEPH will eventually be evaluated for thrombendarterectomy, the only curative treatment for this disease. However, only a subgroup of these patients is eligible for this invasive procedure. In addition, a number of patients will not benefit tremendously from thr Read More

Nitrofurantoin is an antimicrobial agent that is commonly used for the treatment of recurrent urinary tract infection. Nitrofurantoin pulmonary toxicity can present as acute, subacute, or chronic respiratory disease. Common manifestations are dry cough, chest pain, dyspnea, and hypoxemia. Skin rash, arthralgia, and abnormal transaminases are occasionally present. Chest imaging shows patchy infiltrates and fibr Read More

Pulmonary hamartoma usually presents as a single lesion in the periphery of the lung. It occurs in 0.3% of general population, with a higher frequency in male gender and in the sixth decade of life. Endobronchial hamartomas are unusual. This image corresponds to a 81 year-old man with history of coronary artery disease, hypertension, and rheumatoid arthritis who was admitted to the hospital with chest pain and sho Read More

Primary tracheal malignancies are very infrequent, and data relating to them is limited. We recently encountered an 82 yearold woman with a history of aortic stenosis, hypertension, and hypothyroidism, that presented to the clinic with cough and shortness of breath of six month duration. A computed tomography (CT) scan of the chest revealed tracheal thickening with nonspecific nodularity. The patient underwent fiberopti Read More