Pulmonary functions

In 1981, Chinese Restaurant Asthma was reported following capsule administration of MSG to several asthmatics (37). However, the researchers failed to account for other allergens to which the subjects could have been exposed and did not utilize the scientific practice of a "control" substance which would have helped to determine if glutamate triggered this response. In a double-blind crossover study, chronic asthmatics were challenged with MSG or a placebo. No decrease in pulmonary function was observed (39). 

The first SRS-A antagonist, FPL-55712 (26) (149), was discovered before the stmctures of the leukotrienes were detemiined. Although this compound is relatively weak as an antagonist and suffers from a very short half-life in vivo, it played an important role both in leukotriene stmcture elucidation and as a model for later antagonists. In work stmcturaHy related to FPL-55712, LY-171883 was developed (27) (150). LY-171883 was evaluated in several clinical trials before development was stopped. Orally adrninistered, LY-171883 blocked slightly the response to aerosol LTD improved pulmonary function (FEV ) in mild asthmatics (151), decreased the sensitivity of asthmatics to cold air-induced bronchoconstriction (152), and significantly reduced the bronchoconstrictor response to inhaled antigen (153). However, in all these studies the beneficial effects were minimal. 

S. M. Horvath and co-workers. Effects of Sulfuric Acid Mist Exposure on Pulmonary Function, EPA-600/S1-81-044, issued as PB81-208977 by NTIS, Washington, D.C., June 1981. 

In humans, inhaled insoluble barium salts are retained in the lung (47,49). Inhalation of high concentrations of the fine dusts of barium sulfate can result in the formation of harmless nodular granules in the lungs, a condition called baritosis (49). Baritosis produces no specific symptoms and no changes in pulmonary function. The nodulates disappear upon cessation of exposure to the barium salt. However, it is possible that barium sulfate may produce benign pneumoconiosis because, unlike barium carbonate, barium sulfate is poorly absorbed (21). 

O3 Decrement in pulmonary function Coughing, chest discomfort Increased asthma attacks... 

Forced expiration is commonly used to assess pulmonary function in both healthy and impaired individuals. Static measures of lung volumes (TLC, Vj, FRC) fail to detect dynamic changes in pulmonary function that are attributable to disease (e.g., asthmatic airway constriction). Obtaining maximum expiratory flow-volume (MEFV) curves (Fig. 5.21) permits derivation of key parameters in detecting changes in lung function. 

During tiie ongoing assessment, tiie nurse assesses the respiratory status every 4 hours and whenever tiie drug is administered. The nurse notes the respiratory rate, lung sounds, and use of accessory muscles in breathing, hi addition, tiie nurse keeps a careful record of the intake and output and reports any imbalance, which may indicate a fluid overload or excessive diuresis. It is important to monitor any patient with a history of cardiovascular problems for chest pain and changes in the electrocardiogram. The primary health care provider may order periodic pulmonary function tests, particularly for patients with emphysema or bronchitis, to help monitor respiratory status. 

Gordh, T. Linderholm, H. and Norlander, 0. Pulmonary Function in Relation to Anaesthesia and Surgery Evaluated by Analysis of Oxygen Tension of Arterial Blood. Acta Anaesth. Scand. (1958), 2 15-26. 

The Lung Clinical Physiology and Pulmonary Function Tests, Year Book, Chicago, 2nd ed., 1962. 

Demling, R.H., Katz, A., Lalonde, C., Ryan, P. and Jin, L-J. (1987). The immediate effect of burn wound excision on pulmonary function in sheep. The role of prostanoids, oxygen radicals and chemoattractants. Surgery 101, 44-55. 

Dillard, C.J., Litov, R.E., Savin, W.M. and Tappel, A.L. (1978). Effects of exercise, vitamin E and ozone on pulmonary function and lipid peroxidation. J. Appl. Physiol. 45, 927-932. 

Therapy for chronic asthma is directed at suppressing the underlying inflammatory response and normalizing pulmonary function. 

Asthma severity ranges from normal pulmonary function and symptoms only with acute exacerbations to significantly decreased pulmonary function with continuous symptoms. 

Patients with mild intermittent asthma may be symptom-free and have normal pulmonary function between exacerbations. 

Spirometry, an objective measure of pulmonary function, can be used to assist in confirming the diagnosis of asthma. The primary pulmonary function tests used to assist in the diagnosis of asthma are the forced expiratory volume in... 

Therapy for chronic asthma is directed at suppressing the underlying inflammatory response and normalizing pulmonary function. The goals of treatment for chronic asthma are to (1) prevent chronic and troublesome symptoms (2) maintain normal or near normal pulmonary function (3) maintain normal activity levels, including exercise and other physical activities (4) prevent recurrent exacerbations of asthma and minimize the need for emergency department visits or hospitalizations (5) provide optimal pharmacotherapy with minimal or no adverse effects and (6) meet patients and families expectations of and satisfaction with asthma care.1... 

The addition of ipratropium bromide to inhaled p2-agonist therapy in acute severe asthma improves pulmonary function and decreases hospitalization rates in both adult and pediatric patients.31 The benefit of combining ipratropium and albuterol appears to be greatest in moderate to severe exacerbations, and the combination should be considered first-line therapy in severe exacerbations. 

Use the patient s symptoms and pulmonary function tests to classify disease severity. 

Reassess pulmonary function every 20 to 30 minutes. If there was not an immediate response to the inhaled short acting p2-agonist, initiate systemic corticosteroid therapy. If the patient is not improving, add ipratropium to the patient s therapy and continue with a high-dose inhaled short-acting P2-agonist. 

Smoking cessation is the only intervention known to slow the rate of decline in pulmonary function in patients with COPD. 

In symptomatic patients with severe COPD and frequent exacerbations, regular treatment with inhaled corticosteroids decreases the number of exacerbations per year and improves health status however, corticosteroids do not slow the longterm decline in pulmonary function. 

A suspected diagnosis of COPD should be based on the patient s symptoms and/or history of exposure to risk factors. Spirometry is required to confirm the diagnosis. The presence of a postbronchodilator FEV,/FVC ratio less than 70% [the ratio of FEV, to forced vital capacity (FVC)] confirms the presence of airflow limitation that is not fully reversible.1,2 Spirometry results can further be used to classify COPD severity (Table 12-1). Full pulmonary function tests (PFTs) with lung volumes and diffusion capacity and arterial blood gases are not necessary to establish the diagnosis or severity of COPD. 

Leukotriene modifiers (e.g., zafirlukast and montelukast) have not been adequately evaluated in COPD patients and are not recommended for routine use. Small, short-term studies showed improvement in pulmonary function, dyspnea, and quality of life when leukotriene modifiers were added on to inhaled bronchodilator therapy.27,28 Additional long-term studies are needed to clarify their role. 

Pulmonary function tests (PFTs) indicate decreased forced expiratory volume in 1 second (FEN/,), decreased forced vital capacity (FVC), and increased residual volume. Values are typically worse during acute pulmonary exacerbations. 

Inhaled tobramycin (TOBI ) is typically administered to patients 6 years of age and older in alternating 28-day cycles of 300 mg nebulized twice daily, followed by a 28-day washout or off period to minimize development of resistance. Longterm intermittent administration improves pulmonary function, decreases microbial burden, and reduces the need for hospitalization for IV therapy.24,25 Due to minimal systemic absorption, pharmacokinetic monitoring is not necessary with normal renal function. Lower doses of nebulized tobramycin solution for injection have been used in younger children, and studies are underway using 300 mg twice daily in children under age 6. 

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