Respiratory tract/system intravenous

Anaphylaxis most commonly starts with symptoms on the skin or the respiratory tract (table 2). The symptomatology is variable there is no obligatory involvement of all organ systems. A major characteristic of anaphylaxis is the rather rapid onset of symptoms after contact with the elicitor. The interval varies between a few seconds or minutes until 1 or 2 h, partly dependent upon the route of application (rapid onset after intravenous allergen exposure) and degree of sensitization. Experience in insect sting anaphylaxis in... 

Inhalation Inhalation provides the rapid delivery of a drug across the large surface area of the mucous membranes of the respiratory tract and pulmonary epithelium, producing an effect almost as rapidly as by intravenous injection. This route of administration is used for drugs that are gases (for example, some anesthetics), or those that can be dispersed in an aerosol. The route is particularly effective and convenient for patients with respiratory complaints (for example, asthma or chronic obstructive pulmonary disease) as drug is delivered directly to the site of action and systemic side effects are minimized (see p. 219). 

Dermal or intravenous exposure to lewisite leads to local skin edema and pulmonary edema due to increased capillary permeability. The increased capillary permeability results in blood plasma loss and resultant physiological responses collectively referred to as lewisite shock . Lewisite shock may be likened to shock observed in severe bum cases. It has been hypothesized that functional changes in the lungs, kidneys, respiratory tract, cardiovascular, and lymphatic systems may be the result of a disturbance of osmotic equilibrium (Goldman and Dacre, 1989). 

ABSORPTION, FATE, AND EXCRETION Epi is ineffective after oral administration because it is rapidly metabolized in the GI mucosa and liver. Absorption from subcutaneous tissues occurs relatively slowly because of local vasoconstriction, and the rate may be further decreased by systemic hypotension e.g., in shock). Absorption is more rapid after intramuscular injection. In emergencies, it may be necessary to administer Epi intravenously. When relatively concentrated solutions (1%) are nebulized and inhaled, the actions of the drug largely are restricted to the respiratory tract however, systemic reactions such as arrhythmias may occur, particularly if larger amounts are used. 

Pulmonary administration of medicines currently has the primary objective to achieve local effects in the respiratory tract of patients with chronic diseases like asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF). For half a century, inhalation therapy has been the cornerstone in the management of these diseases and the often life-time therapies aim to suppress inflammatory processes and bacterial infection in order to reduce hospitalisations and to improve the patient s quality of life. They also give relief to the patient in moments of bronchoconstriction. The advantages of pulmonary administration of medicines for local treatment are well known. The active substances are delivered directly to the site of action which leads to a faster response than via the systemic route. It may also result in higher local active substance concentrations and this could reduce the total dose by as much as a factor 10 compared to oral or intravenous administration. This has the advantage that systemic side effects are reduced and in combination with being a non-invasive method of administration, inhalation therapy may lead to better patient compliance. 

In 1907 Windaus and Vogt completed the first chemical synthesis of histamine and soon after Sir Henry Dale and coworkers began investigations that showed that histamine was a powerful vasodepressant, it stimulated smooth muscle from the gut and respiratory tract and caused shock when injected into laboratory animals mimicking the systemic effects of anaphylaxis. These early results were followed by demonstration of the involvement of histamine in vascular reactions of the skin and the observation that morphine caused the so-called triple response in human skin, that is, the event sequence of an initial red spot followed by a red irregular flare and a fluid-filled wheal. Over 30 years later antihistamines were shown to reduce morphine-induced skin wheals, and histamine itself was detected in effluents of isolated perfused cat gastrocnemius muscle after arterial injection of opium alkaloids. Released histamine was also detected in cat skin, and raised levels were found in plasma after intravenous injection of morphine. 

Should the infant exhibit an elevated temperature or other signs of infection or sepsis, the physician should promptly and thoroughly evaluate the fever of unknown origin. Accordingly, the ears, upper respiratory tract, lungs, urinary tract, and any surgical wounds must be completely examined. If no source of systemic infection can be detected, the intravenous tubing and bottle or bag of nutrient solution should be cultured and replaced. 

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