Emphysema disease Respiratory system

Respiratory system (chronic obstructive pulmonary disease [COPD emphysema, chronic bronchitis], acute obstructive lung disease [asthma], chronic restrictive lung disease [connective tissue lung disease])... 

Inhalation aerosols have been used for the delivery of drugs to the respiratory system since the mid-1950s. The most common dosage form for inhalation is the metered-dose inhaler (MDI), by which the drug is delivered from a pressurized container using a liquefied gas propellant. Medication delivered via this dosage form has allowed for a quick therapeutic response to the symptoms of asthma, emphysema, and chronic obstructive pulmonary disease (COPD), and has resulted in an improvement in the quality of life for millions of asthma sufferers. 

While the respiratory system is well-equipped to defend against exposure to a vast array of toxic substances, the intricate cellular and molecular mechanisms designed to repair injured lung tissues often fail, resulting in a number of chronic lung diseases, including cancer, fibrosis, asthma, hypersensitivity pnuemonitis, and chronic obstructive pulmonary disease (COPD), which is a combination of bronchitis and emphysema. 

Respiratory toxicity Upper respiratory system (nose, pharynx, larynx, and trachea) and the lower respiratory system (bronchi, bronchioles, and lung alveoli) Pulmonary irritation Asthma/bronchitis Emphysema Allergic alveolitis Fibrotic lung disease Lung cancer... 

In addition to acute lung effects and chronic renal effects, long term exposure to cadmium may cause other severe effects on the respiratory system. Reduced pulmonary function and chronic lung disease indicative of emphysema have been observed in workers who have had prolonged exposure to cadmium dust or fumes (Exs. 4-29, 4-22, 4-42, 4-50, 4-63). In a Study of workers conducted by Kazantzis et a ., a statistically significant excess of worker deaths due to chronic bronchitis was found, which in his opinion was directly related to high cadmium exposures of 1 mg/m or more (Tr. 6/8/90, pp. 156-157). 

Respiratory history As noted above, formaldehyde has recognized properties as an airway irritant and has been reported by some authors as a cause of occupational asthma. In addition, formaldehyde has been associated with cancer of the entire respiratory system of humans. For these reasons, it is appropriate to include a comprehensive review of the respiratory system in the medical history. Components of this history might include questions regarding dyspnea on exertion, shortness of breath, chronic airway complaints, hyperreactive airway disease, rhinitis, bronchitis, bronchiolitis, asthma, emphysema, respiratory allergic reaction, or other preexisting pulmonary disease. 

Introduction - This chapter will review two groups of drugs used for the relief of various manifestations of lung diseases, namely, the bronchodi-lators to terminate or prevent an asthmatic attack, and the pulmonary vasodilators for the treatment of pulmonary hypertension. It should be noted first of all that in the treatment of respiratory diseases the approach is symptomatic rather than etiotropic. The causes of bronchospasm and pulmonary hypertension are difficult to control. Disease processes as such, for example, viral infections of the respiratory system, pulmonary emphysema and pulmonary arteriosclerosis, cannot be treated successfully by drugs, so that one has to resort to treatment of symptoms. 

Sulfur dioxide, emitted primarily by coal-burning power plants and industrial smelters. Is a powerful irritant that affects the respiratory system. The adverse health effects related to high exposures include respiratory illness, alterations in the lung s defenses, and aggravation of existing respiratory and cardiovascular disease. Children, elderly persons, and people with health conditions such as asthma, bronchitis, emphysema, or cardiovascular disease are especially sensitive to increased sulfur dioxide levels. As we learned in Chapter 9, sulfur dioxide is also the major precursor to acid rain. 

Most of the information on the effects of air pollution on humans comes from acute pollution episodes such as the ones in Donora and London. Illnesses may result from chemical irritation of the respiratory tract, with certain sensitive subpopulations being more affected (1) very young children, whose respiratory and circulatory systems are poorly developed, (2) the elderly, whose cardiorespiratory systems function poorly, and (3) people with cardiorespiratory diseases such as asthma, emphysema, and heart disease. Heavy smokers are also affected more adversely by air pollutants. In most cases the health problems are attributed to the combined action of particulates and sulfur dioxides (SO2) no one pollutant appears to be responsible. Table 4.2 summarizes some of the major air pollutants and their sources and effects. 

The use of recombinantly produced (X,-antitrypsin would reduce the risk of transfusion-related viral disease however, its half-life is too short to produce adequate serum levels without daily infusion. Studies have shown that the recombinant product can be administered as an aerosol. It diffuses across the respiratory epithelium, enters the lung lymph, and eventually reaches the systemic circulation. Unfortunately, it is not known whether this therapy has any influence on the development or progression of emphysema. Further carefully controlled, multicenter trials are necessary. 

More broadly, timolol therapy should be considered with caution in patients with any significant sign, symptom, or history for which systemic beta-blockade would be medically imwise.This includes disorders of cardiovascular or respiratory origin (e g., asthma, chronic bronchitis, and emphysema) as well as many other conditions. Spirometric evaluation after institution of timolol therapy may help to identify patients in whom bronchospasm develops after commencement of therapy. In general, however, patients with asthma and other obstructive pulmonary diseases should avoid this drug. Sympathetic stimulation may be essential to support the circulation in individuals with diminished myocardial contractility, and its inhibition by P-adrenoceptor antagonists may precipitate more severe cardiac feilure. 

Second, inhaleables enable effective drug targeting to the lungs for relatively common respiratory tract diseases such as asthma, emphysema, bronchiectasis and chronic bronchitis. This direct delivery most often results in a better treatment outcome while potentially requiring less drug than if given systemically either orally or by injection. 

In addition to the prevalences of the diseases affecting the organ systems, one must also consider the severity of the effect. Obviously, emphysema has much more impact on the susceptibility of the lung to respiratory pollutants than hay fever. Similarly, the impact of mild anemia on the development of heart disease is less than that of high blood pressure or rheumatic fever. 

If there is insufficient bicarbonate to compensate for the extra acid, acidosis can occur. Formally, acidosis is a significant decrease in pH of extracellular fluid. This condition can occur due to both respiratory and metabolic abnormalities. Respiratory acidosis occurs when breathing abnormalities result in CO2 retention and an elevation in Pco2 in alveoli and arterial blood (known as hypercapnia). The term Pco2 refers to the partial pressure of CO2 in the pulmonary alveoli during respiration. Retention of CO2 can result from inadequate ventilation during anesthesia, certain conditions that result from central nervous system disease, or from drug use, and it is observed with emphysema. Metabolic acidosis occurs with starvation, uncontrolled diabetes mellitus with ketosis, and with electrolyte and water loss due to diarrhea.il... 

Lung disease blocking gas diffusion (e.g., emphysema, pneumonia, bronchitis, asthma) depression of respiratory center by drugs, cardiopulmonary arrest, stroke, poliomyelitis, or nervous system... 

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