Cure Asthma Forever
The exposure of asthmatic patients to high altitudes must be carefully evaluated in advance, keeping in mind the following recommendations 12 1. Asthma must be under control and in a stable state. 2. Patients should not discontinue their regular antiasthmatic prophylaxis and should always keep rescue drugs with them. At high altitude, the use of a spacer for a metered dose inhaler is more important than at sea level, 3. As at sea level, the patients should always be pre-medicated with short-acting beta2agonists and or steroids before any intense physical effort, especially those who have already shown bronchospasm induced by exercise (the use of leukotriene inhibitors should also be considered). 5. Trekking to high altitudes in remote areas would be better done in the presence of a physician. It is very important that the patient has adequate supplies of drugs, possibly packed in two different places, to avoid risks in the event of loss. In any case, patients must know how to manage...
The PAQLQ developed by Juniper et al. (1996) has been designed to measure the problems that children between the ages of 7 and 17 experience as a result of asthma extracts from the self-administered version are shown in Appendix El 1. The PAQLQ has 23 items relating to three dimensions, namely symptoms, activity limitations and emotional function. Items are scored from 1 to 7. Three of the activity questions are individualised with the children identifying important activities at the beginning of the study. There is a global question, in which children are asked to think about all the activities they did in the past week, and to indicate how much they were bothered by their asthma during these activities. The items reflecting each dimension are averaged, forming three summary scales that take values between 1 and 7.
The association of asthma with an increased risk of pre-eclampsia is much more controversial. In a review of the incidence of pre-eclampsia in asthmatic women, Schatz and Dombrowski (2000) report significantly increased incidences (RR 2.2 3.2) in three studies, but no increase in five studies. In a historical cohort analysis using hospital discharge data of 8672 cases of pregnant asthmatics in Canada, Wen and colleagues (2001) demonstrated an increased risk of pre-eclampsia (adjusted odds ratio 1.84, 95 CI 1.64, 2.05) in women with asthma compared to a control population. There are several possible explanations for this association ifindeed it is real. First the prevalence of pre-existing hypertension has been reported to be approximately 2 3.5-fold higher in pregnant asthmatic women (Schatz and Dombrowski, 2000). However, the study by Wen and coworkers controlled for pre-existing hypertension (Wen et al., 2001). Second there may be common pathogenic factors for asthma and...
It is important to differentiate routine asthma care from that in acute severe asthma. This section will focus on acute or near-fatal asthma, a condition that is largely reversible so related deaths should be considered avoidable. Interventions are aimed at preventing respiratory and secondary cardiac arrest (AHA & ILCOR 2000, Scottish Intercollegiate Guidelines Network (SIGN) & British Thoracic Society (BTS) 2003). Most deaths related to acute severe asthma occur outside hospital. Contributing factors include patients with less severe asthma attacks may seek emergency care but after treatment are discharged home and deteriorate further. Cardiac arrest may occur in patients with severe asthma as a hypoxia from mucus plugging or severe bronchospasm
Asthma is one of the most widespread diseases in the world, even if its prevalence and severity differ widely among countries and individuals. At altitude, the main problems which emerge are hypoxia and environmental and trigger factors such as exercise, hyperventilation in dry and cold air (the severity of bronchospasm induced by exercise is enhanced by hyperventilation in cold and dry air 5,22 , while there is a reduction in aeroallergens and atmospheric pollution. Hyperventilation Asthma attack of dry and cold air At 1500-2000m hypoxia is not severe, and the main environmental feature is the reduction in, or absence of, pollen, house dust mite and environmental pollution 8 , which can play a key role in reducing the bronchial inflammation underlying airways hyper-responsiveness 60 . Avoidance of allergen exposure (especially to mite allergens) is often recommended in asthma management and a considerable reduction in exposure to allergens exists in mountain environments, a fact...
Strasburger, Victor C., and Robert T. Brown. Adolescent Medicine A Practical Guide. 2d ed. Philadelphia Lippincott-Raven, 1998. This book addresses the physical and psychosocial problems of teenagers that physicians are most likely to treat. The emphasis is on practical information. Applied diagnostic and treatment guidelines cover conditions such as asthma, diabetes mellitus, developmental problems, headaches, sexually transmitted diseases and pregnancy, depression, and eating disorders.
Studies of preventable death caused by drug therapy (contrasted to death from an adverse drug reaction) are difficult to review systematically. Most focus on specific diseases, e.g., asthma. Preventable deaths are rather rare events on a population basis. All studies oversampled for death. That is, in effect, they searched for patients who had died, rather than counting the deaths in a sample drawn sequentially or at random from a general population at risk.27-34 Examples are described below.
A properly balanced combination of all these components may be used for an explanation of age-specific morbidity and mortality patterns in human populations, including cancer morbidity. The obvious advantage of such an approach is that by dividing individual aging into the processes with different age-related dynamics, one has an opportunity to use information from different studies focused on specific aspects of individual aging. For example, the age pattern of ontogenetic vulnerability used in the respective component of cancer incidence rate in our study was obtained from asthma studies (see 12 ). A similar pattern is also produced in the studies of other chronic diseases, as shown in 11 . The limitations of this approach are associated with the large amounts of data required for identification of model parameters.
Heat stress in the northern latitudes where the populations are not acclimatized would be the primary health impact of warming 8 . Serious illness and increased mortality is indicated in some regions (including some urban areas in the US) with a high degree of air pollution. Asthmatics and those with respiratory difficulty will be particularly affected by heat stress. An equally serious concern will be the prevalence of vector-borne disease 9 likely to be encouraged by global warming. These include malaria, schistosomiasis, dengue fever, yellow fever, and the African sleeping sickness. The reach of malaria, for instance, could extend from about 45 of the world population at the present time to as much as 60 , as a result of the projected warming. Developing countries, some of them unfortunately in low-lying areas and also susceptible to sea-level rise, will be particularly hard hit by this public health crisis. The major indirect health effects of global warming are likely to be due...
Juniper et al. (1996) evaluated the Paediatric Asthma Quality of Life Questionnaire (PAQLQ) by examining reliability in children aged 7 to 17 who had stable asthma. The results are shown in Table 3.12, and it can be seen that all but one of the ICC values were above 0.80. These findings suggest that the PAQLQ has high test retest reliability in stable patients.
There is a distinction between the common physiologic GER of childhood and pathological gastro-esophageal reflux disease (GERD). This more severe form of reflux can interfere with growth, and cause gastroesophageal and respiratory symptoms. GER has been linked to asthma, and pulmonary symptoms are significantly higher in children with GER than those without (Gold 2005). Children and adolescents with GER are more likely to present with cough and other respiratory symptoms than complaints of heartburn . Asthma itself causes GER by a variety of mechanisms. Hyperinflation changes the pressure gradient across the lower esophageal sphincter, increases negative intrathoracic pressure and alters the relationship between the diaphragm and lower esophageal sphincter. This may be exacerbated by some asthma medications that decrease lower esophageal sphincter pressure.
Drugs contained within the formulations may also alter gastric motility. For example adrenergic agonists, particularly E2-agonists such as salbutamol, delay gastric emptying. In asthmatic subjects an variable quantity of the inhaled drug may be swallowed, and hence even though the drug is not taken by the oral route, it may still have an effect on the gastric emptying of other drugs. Tricyclic antidepressants and some anti-Parkinsonian drugs depress gastrointestinal motility. Dopaminergic antagonists e.g. domperidone, and cholinergic agonists e.g. bethanechol, enhance gastric motor activity.
As the problem of respiratory patients at high altitude is very important, we add a short summary of the guidelines for asthmatic patients and for patients suffering from chronic obstructive pulmonary disease published on HAM&B 12 and discussed during the meeting. Exposure to high altitude does affect patients with chronic lung disease. Patients with obstructive disease (asthma and chronic obstructive pulmonary disease (COPD)) can have specific problems when exposed to altitude 53 . In fact, in these cases not only hypoxia but also other climatic aspects of high altitude play a potential role in the patient's wellbe-ing. At high altitude, in fact, there is a decrease in barometric pressure, inspired oxygen pressure, temperature, humidity, density of air but, and at the same time, an increase in solar radiation and wind. The effect is reported in Table 1.
Polyamines are essential for cell growth and development. They regulate many functions, including cell division, migration, ion channel regulation, apoptosis, and the cellular synthesis of DNA, RNA, and proteins. A recent review on the roles of polyamines in the lung emphasized studies on respiratory cell biology and polyamine uptake (1). The primary goal of this chapter is to review evidence that polyamines contribute to pheno-typical changes in pulmonary vascular cells that underlie the pathogenesis of pulmonary arterial hypertension. Because arginases can regulate polyamines, their potential role in the pathogenesis of pulmonary hypertension and asthma also will be reviewed. The data suggest polyamines may be future therapeutic targets for pulmonary hypertension, although clinical trials measuring polyamines and their regulation are lacking. Arginases and polyamines may have important roles in the development of other lung diseases, such as fibrosis and asthma. Although nonvascular...
There are many potential pitfalls that lie in the way of researchers on the route from the discovery of a mutation in human DNA that codes for a pharmacologically important protein to the development of a clinically useful pharmacogenetic test. Very few such tests have been developed as yet, but a considerable number seem likely to be found useful over the next decade in guiding the treatment of patients with cancer, asthma, depression, hypertension, and pain.
Disorders found to be associated with changes in the sequence of a single gene have been associated with an increased risk of preterm birth, often as a result of a predisposition to polyhydramnios in pregnancies with fetuses with changes in the sequence of that single gene. Among these conditions are myotonic dystrophy, Ehlers-Danlos syndrome, Smith-Lemli-Opitz syndrome, and neurofibromatosis. However, like many other complex human diseases, such as obesity, hypertension, diabetes, and asthma, preterm birth is a complex trait and possesses the following features non-Mendelian transmission, the involvement of multiple genes, and gene-gene and gene-environment interactions. Research on the genetics of preterm birth thus faces significant challenges. The approaches available for the identification of genes that may be associated with a particular trait include positional cloning, the identification of positional candidate genes, whole-genome association analysis, and functional candidate...
The absorption of drugs such as penicillin V and G, theophylline and erythromycin is reduced by the presence of food, but food delays the absorption of other drugs (cimetidine, metronidazole and digoxin). The effect of food on drug absorption can be dependent on the type of dosage form used, the excipients and the form of the drug, for example erythromycin stearate in film coated tablets demonstrated reduced absorption with food, erythromycin estolate in suspension was unaffected by food, but absorption of erythromycin ethylsuccinate in suspension and erythromycin estolate in capsules was increased by the presence of food77. A co-administered meal decreases the oral absorption of bidisomide and does not influence the oral absorption of the chemically-related
Nonprescription medicines are important aspects of medications use for a number of reasons. First, OTC status is not limited to the safest drugs available. An international comparison of which medicines are available without a prescription in various nations of the industrialized world shows that legal, ethical, and political considerations may be as important as safety data. For example, asthma is a dangerous, non-self-limiting disease that requires medical attention. Epinephrine, a potent drug, was approved by the FDA in 1939. Most epinephrine products are prescription-only. However, epinephrine administered by a metered-dose inhaler is available without a prescription for treatment of asthma. (The FDA has expressed concern regarding OTC status for this dosage form.)
Drug safety also can differ from clinical trial to postmarket use. For example, Schiff et al. studied the toxicity of theophylline, a drug once a mainstay of asthma therapy. They found many errors in its use and concluded that theophylline's overall risk benefit ratio for inpatients may be less than that measured in well-controlled studies of the drug's efficacy because of these errors. 30
Graded concentration-effect studies may be useful for establishing the mechanism of action of a drug at a molecular or biochemical level by assessing the drug-receptor interaction. The xanthine analog, theo-phylline, which is a potent relaxant of bronchial smooth muscle, is used for the treatment of asthma. However, theophylline has a narrow therapeutic range, and at concentrations above this therapeutic range patients can experience vomiting, tremor, seizures, and cardiac arrhythmias. Theophylline interacts with multiple receptors that could account for its
The molecular probes developed during the characterization of the different PDE families have been widely used to study the expression of the different PDEs in various organs. This has led to the discovery that inflammatory cells express mostly PDE4 (Torphy, 1998). This observation, together with the notion that activation of the cAMP signaling pathway blocks activation of lymphocytes, have prompted the investigation of PDE4 inhibition as a strategy to suppress inflammation. There is now a large body of information available on the antiinflammatory effects of PDE4 inhibitors, and clinical trials are underway. The use of theophilline for the treatment of asthma is limited by the general toxicity and the cardiovascular effects of this drug. With the development of PDE4 selective inhibitors, the cardiovascular effects of theophilline should be eliminated.
A program may promote the use of certain (cheaper) drug products even if, as a consequence, many patients may not achieve their therapeutic objectives and even if total costs of care increase. Examples were given in earlier chapters to explain possible origins of PDRM. Here is another example. In their review of prescribing for asthmatic patients in East London, Naish et al. concluded Pressure to reduce the cost of asthma prescribing may lead to a lowering of the ratio of prophylactic to bronchodilator treatments. However, reducing prophylactic prescribing would run contrary to the British Thoracic Society guidelines and might worsen the quality of asthma care.1 Incidentally, asthma is not expensive to treat correctly. Furthermore, the total cost of treating asthmatic patients is usually less when they are treated correctly, because undertreatment usually results in expensive emergency department visits and hospitalizations.
Chronic disease management assists individuals to manage diseases such as asthma, hypertension, or diabetes. It includes regular screening, counseling and education, skills development, and access to appropriate medical care in the correctional setting and after release. Quality screening, treatment management, and education for chronic infectious disease (STIs, tuberculosis, HIV, hepatitis, asthma, high blood cholesterol and pressure, diabetes)
Infants with BPD CLD have nutritional and fluid problems because of fluid sensitivity and increased metabolic needs, have difficulties with reactive airways (wheezing), and are quite vulnerable to infections, especially respiratory infections (Vaucher, 2002). Surprisingly few studies of the standard medications used to treat infants with BPD CLD have been conducted, including diuretics and bronchodilators (Walsh et al., 2006). Modest improvements in survival and BPD CLD rates have been reported with intramuscular injections of vitamin A (Darlow and Graham, 2002). The likelihood of persistent respiratory problems during infancy is higher in preterm infants with BPD CLD than in those without BPD CLD. They may develop significant wheezing with respiratory infections (viral broncholitis) and may need to be rehospitalized, placed back on a ventilator, or even given exogenous surfactant (Kneyber et al., 2005). Preterm infants are especially vulnerable to respiratory syncytial virus (RSV)...
The elimination clearance of caffeine, a CYP1A2 substrate, was shown to decrease by a factor of two by midgestation and by a factor of three by the third trimester compared to the postpartum period (45). Although the intrinsic hepatic clearance of theophylline was reduced during pregnancy (Figure 22.3), there was substantially less change in its hepatic clearance because of the pregnancy-associated decrease in theophylline binding to plasma proteins (20). As a result of the offsetting changes in renal and hepatic clearance referred to previously, the total elimination clearance of theophylline was unchanged in the third trimester of pregnancy
Psychosomatic medicine embraced the notion that personality and physiology are intertwined. Psychosomatic theorists believed that certain diseases, such as diabetes, asthma, and hypertension, were associated with particular personality characteristics. They suggested that personality influenced the development of specific diseases. Although much of this theorizing has been disproved, these theorists did return the focus to investigating the interactive nature of a person's psychological and physiological makeup.
DUE may be followed up with administrative enforcement of prescribing restrictions or with educational programs to change prescribing. Consistent with the prescribing focus of DUE, the prescribing physician is usually the target. One comparative study of patient-oriented DUE suggests that DUE directed at physicians did not increase the efficiency of prescribing for asthmatic patients (Table 6.2). However, DUE targeted at physicians and pharmacists significantly decreased prescription expenditures, with a smaller (although not statistically significant) total outlay for care per member per month.39 Average Monthly Cost per Patient for Asthma Medications by Study Group Average Monthly Cost per Patient for Asthma Medications by Study Group
The second approach is to change the microsystems of care. For example, Chapter 9 describes a Danish asthma study that changed the relationship between physicians, pharmacists, and patients into a pharmaceutical care system. It was not directed at prescribing improvement per se, but that is what happened when physicians, pharmacists, and patients cooperated to improve patient outcomes. (See Chapter 9.) As part of a systems approach to improving outcomes, PDRM indicators (described in Chapters 2 and 3) could replace or supplement specific drug prescribing indicators.
Developmental changes in liver and kidney excretory function during infancy and childhood may necessitate dose adjustments to achieve a therapeutic drug concentration. For example, theophylline dose recommendations are age specific during childhood to compensate for changes in drug clearance. The overall elimination clearance of theophylline (renal excretion + hepatic metabolism) is markedly delayed in newborns (20 mL min kg in preterm newborns), and the recommended dose in this population is 4 mg kg day. However, theophylline clearance in children (100 mL min kg) is 40 higher than in adults (70 mL min kg), and children will require higher body-weight-normalized doses than do adults 42-44 . The effect of the age-dependent clearance rate of theophylline on the dose required to maintain a therapeutic drug level is shown in Figure 23.8. In this study, more than 3500 serum theophylline concentrations were measured in 1073 patients who ranged in age from 1 to 73 years (median, 9 years)...
Theophylline neurotoxicity and cardiotoxicity are increased in older patients. Although it is unclear whether decreased theophylline clearance and increased exposure in older patients fully explain this apparent sensitivity, clinical reports are uniform in identifying age as a major contributing risk factor for theophylline toxicity (95, 96). This has resulted in much less use of theophylline in older patients.
Cook et al. (1993) compared the same questionnaire when interviewer- or self-administered, on a sample of 150 asthma patients. When using the self-administered version, patients recorded more symptoms, more emotional problems, greater limitation of activities, more disease-related problems and greater need to avoid environmental stimuli. On average, 47 of items were endorsed when self-administered, but only 36 when interviewed.
A treatment guideline for bronchial asthma (given specific diagnostic details) might recommend combination therapy of regular daily inhalations of a preventer medicine like beclomethasone and occasional use of an inhaled rescue medicine like albuterol. (Albuterol is an adrenergic agonist, similar to epinephrine, that can open a constricted airway during an attack.) Increasing frequency of albuterol metered-dose inhaler (MDI) use may reflect either incorrect inhaler technique or worsening status of disease control. Patients with good inhaler technique who have to increase their frequency of rescue medicine use may need medical attention to find out why their asthma is going out of control. The maximum appropriate daily dosage of albuterol MDI is eight inhalations per day. An MDI containing 17 g of drug would contain enough for 200 inhalations. The minimum prescription refill interval that is consistent with that guideline would then be about 25 days.*
Sensitised with recurrent exposure may suffer more severe reactions. Pulmonary migration is associated with fever, dyspnoea and asthma, associated with eosinophilia (Spillman, 1975). Larvae are found in the terminal air-spaces and bronchioles, provoking an intense eosinophilic inflammatory reaction and consolidation. This complication is occasionally fatal (Beaver and Danaraj, 1958).
Primary granules contain eosinophil peroxidase and Charcot-Leyden crystal protein. The eosinophil peroxidase is distinct from neutrophil myeloperoxidase and can mediate damage to micro-organisms and tissues and bronchoconstriction in asthma. Charcot-Leyden crystal protein is found in tissues and fluids in association with eosinophil inflammatory reactions and may have a role in respiratory disease.
Basophils are the least abundant leucocytes, accounting for less than 0.5 of bone marrow and peripheral blood leucocytes. Basophils arise from a common basophil-eosinophil progenitor cell, mature in the marrow over a period of 2-7 days and after release in the circulation last for up to 2 weeks. They are the key mediators of immediate hypersensitivity reactions such as asthma, urticaria and anaphylaxis. In addition, they have been implicated in delayed cutaneous hypersensitivity reaction. Basophils are stimulated by a number of mediators, such as IgE, IL-3, C5a, GM-CSF, insect venoms and morphine, to release the contents of their granules such as histamine.
When the asthmatic response is triggered by an external allergen such as pollen, a major part of the primary immune response consists of the release of histamine from mast cells, a process termed 'degranulation'. Histamine has a wide range of actions in tissues, but in the bronchial tissues it causes constriction of smooth muscle via the H, receptors. This action can be prevented by sodium cromoglycate, which inhibits mast cell degranulation. As a result it has a powerful prophylactic action in asthma, but is of little use for relief of an acute attack. It is valuable for the management of extrinsic asthma and exercise-induced asthma. Cromoglycate is now thought to have an additional actions such as inhibition of pulmonary sensory C-fibre discharge38 39. Anew drug in the category of anti-allergies is nedocromil sodium, which is equipotent with sodium cromoglycate40.
When an asthmatic attack has been triggered by histamine at H1 receptors, the objective is to redilate the bronchi with a E2 receptor agonist in the upper and mid airways. These cause relaxation of bronchial smooth muscle and thus allows the airway to dilate. These materials are mainstays of the treatment of asthma, as well as a variety of other pulmonary diseases in which it is desired to decrease airway resistance. They provide rapid symptomatic relief where the predominant cause of reduced airway calibre is bronchial smooth muscle contraction, or they may be used as regular maintenance therapy to avert symptoms. Their preventative effect is particularly seen in the suppression of exercise-induced asthma41. Beta receptor agonists also increase the rate of mucociliary clearance, known to be abnormally slow in patients with obstructive airways disease. Inhaled E2 receptor agonists are less effective if airway inflammation is a major factor in the disease. The oldest member of the...
Feinstein et al. reported (1998) the medical status and history of health care utilization of juvenile offenders on admission to an 80-bed detention center in Birmingham, Alabama. African Americans made up 74.5 , while white non-Hispanic males made up 15.4 of the population. Only 7.3 of the juveniles were African-American females and 2.8 white non-Hispanic females. The most common condition was asthma. Other common conditions included orthopedic problems, mental illness, hearing-related problems, and pregnancy. Almost one-fifth (16.5 ) reported a history of hospitalization, the majority of these resulting from trauma-related injuries. Despite these findings, only
Inappropriate asthma treatment Numerator Patient with asthma receiving more than two rescue inhalers and fewer than one preventer inhaler in 1 month. Denominator Number of patients with asthma receiving beta agonists by inhaler. Rationale High-rescue inhaler use and low preventer use both may predict emergencies and deaths in asthmatic patients. (Each additional MDI cannister doubles the risk of asthmatic crisis.8,9) Asthma readmission Numerator A patient with asthma who was readmitted to hospital or who had emergency department visits within 15 days of last hospitalization. Rationale Frequent emergency care or hospital admission is inconsistent with appropriate management of asthma. (This indicator could also be written as a rate indicator if some such events were considered acceptable.) Scope Provider and practice group level outcome of medications use process, quality of care, and other factors contributing to asthma control. Use of appropriate medications for asthmatic patients
Treatment for reactive airway disease, for which all premature infants are at risk, and treatment of infection may contribute to higher average outpatient costs among those born pre-term. The relatively high outpatient medical care costs in the upper tail of the medical care cost distribution for those born at 32 to 36 weeks of gestation noted earlier is likely explained, in part, by the costs incurred by individuals with developmental disabilities. LBW is clearly a risk factor for developmental disabilities and their associated costs and one that is correlated with gesta-tional age. The extent to which these risk factors contribute independently to these developmental disability costs is not fully understood. Future studies should investigate costs for other disabling conditions which were not available for these analyses but are prevalent among preterm infants such as asthma and attention deficit hyperactivity disorder.
As discussed in Chapter 2, the available evidence suggests that schizophrenia and other major mental illnesses, like many other biologically caused disorders such as asthma or hypertension, have a large genetic component. Persons with this genetic component are often vulnerable to environmental stresses or triggers that promote specific biological events, such as changes in neurotransmitter functioning. Some aspects of family life may cause stress, which in turn may trigger relapse or the recurrence of symptoms. In any case, families are neither a necessary nor sufficient cause of serious mental illness.
A monitoring plan is formed for follow-up of the indicators at specific times, for example, improvement or remission of symptoms of asthma in 3 to 6 days following the initiation of inhaled steroids. If symptoms have not improved in 3 to 6 days, the cause has to be found and the therapy has to be corrected, or a therapeutic success may be impossible. For example, suppose a patient with asthma is not getting the customary effect from his beta-agonist metered-dose inhaler (MDI) and is using it more frequently. Two important possibilities are (1) the patient's inhaler technique has degraded and the patient is not getting the full dosage into his lungs and (2) the patient's asthma is worsening, perhaps because of exposure to allergens. Possible resolutions of this problem would include (1) assessing and correcting inhaler technique, (2) identifying and eliminating the new provocation from the patient's environment, or (3) initiating steroid therapy. Solution (1) is well within the...
There is often a tendency to look at migrant health only from an infectious diseases perspective. Noninfectious diseases should not be forgotten, as the world is changing rapidly. Cardiovascular diseases, diabetes, asthma, respiratory diseases linked with smoking, cancers, occupational diseases and injuries, exposure to environmental hazards, mental disorders are on the increase in the developing world, as a result of rapid urbanisation, socioeconomic and behavioural changes (WHO, 1998). The recent Kosovo crisis revealed the burden of chronic diseases in the refugee population. Surveys have shown that, as a result of lifestyle changes, the incidence of cardiovascular diseases in immigrants to Canada or USA tend to
There is some suggestion that Phase I biotransformations catalyzed by CYP2C are decreased with age, with modest decreases in clearance of warfarin (CYP2C9) and phenytoin (CYP2C19) reported in older individuals. However, this is much less well established (17, 18). Similarly, Phase I biotransformation by CYP1A2 may be somewhat decreased in older individuals, and decreased theophylline and caffeine clearances have been reported (19). However, this too is not well established.
In 1981, a capsule containing a balloon filled with drug was reported, which could be actuated in the gastrointestinal tract when required, by the application of a radio signal89. This technique has been used to study absorption at various sites in the gastrointestinal tract. To locate the capsule, it is swallowed with a small dose of barium sulphate to aid its localisation within the gut and is triggered when required. The absorption of frusemide was compared in 5 subjects using the device90. The drug was released in the ileo-caecal area in 3 subjects and in the ascending colon in the other two. Maximum plasma concentrations were lower after the release of the drug in the colon, and there was a forty-fold difference between absorption from the stomach and colon with bioavailabilities of 20 and 3 respectively. The capsule was also used to study the absorption of theophylline from the stomach, ileum and colon91. The mean relative bioavailability of theophylline was 86 after releasing...
Tissues and found highest in liver 71 . The physiological signi cance of the GSNOR pathway was impressively demonstrated by experiments with GSNOR knockout mutant mice 4 , which showed greatly enhanced levels of RSNO and became hypotensive under anesthesia. Human asthmatics show the combination of enhanced GSNOR levels and depressed GSNO in the bronchial uids. It suggests that chemically incorporated NO stores are depleted in asthmatic patients. Since the remainder of NO is exhaled, the unbalance between NO and S-nitrosocompounds may be the reason for the observed increase of exhaled NO in asthma 70,72 . Recent studies on the decomposition of low-molecular-weight S-nitrosothiols in tissue homogenates of rats have provided more evidence that enzymatic pathways contribute signi cantly to the process 73 . The above publications leave no doubt that signi cant enzymatic pathways for S-denitrosation of LMW nitrosothiols operate in mammals. Their role in the regulation of endogenous pool of...
The most widely cited examples of parenteral prodrugs are water-soluble prodrugs of steroids. Adrenal corticosteroids such as prednisolone, methylpred-nisolone, hydrocortisone, betamethasone, and dexamethasone exhibit poor aqueous solubility. They are all commercially available as water-soluble sodium hemisuccinate esters and or sodium phosphate esters. These water-soluble prodrugs are used in the emergency treatment of bronchial asthma, acute adrenal cortical insufficiency, and allergic drug reactions and are given intraarticularly or intrasynovially in the treatment ofjoint inflammation. These prodrugs regenerate the parent steroid by enzymatic cleavage of the hemisuccinate or phosphate ester in vivo (Melby and St. Cyr, 1961).
The patient's arterial Pco2 is lower than the normal value of 40 mm Hg because hypoxemia has stimulated peripheral chemoreceptors to increase his breathing rate hyperventilation causes the patient to blow off extra C02 and results in respiratory alkalosis. In an obstructive disease, such as asthma, both forced expiratory volume (FEV,) and forced vital capacity (FVC) are decreased, with the larger decrease occurring in FEVi. Therefore, the FEV FVC ratio is decreased. Poor ventilation of the affected areas decreases the ventilation perfusion (V Q) ratio and causes hypoxemia. The patient's residual volume (RV) is increased because he is breathing at a higher lung volume to offset the increased resistance of his airways. 5. The answer is C II E 3 a (2) . The cause of airway obstruction in asthma is bronchiolar constriction. (32-adrenergic stimulation (( -adrenergic agonists) produces relaxation of the bronchioles.
Selye's general adaptation syndrome involves three stages of physiological response alarm, resistance, and exhaustion. During the alarm stage, the organism detects a stressor and responds with SNS and hormonal activation. The second stage, resistance, is characterized by the body's efforts to neutralize the effects of the stressor. Such attempts are meant to return the body to a state of homeostasis, or balance. (The concept of homeostasis, or the tendency of the body to seek to achieve an optimal, adaptive level of activity, was developed earlier by Walter Cannon.) Finally, if the resistance stage is prolonged, exhaustion occurs, which can result in illness. Selye referred to such illnesses as diseases of adaptation. In this category of diseases, he included hypertension, cardiovascular disease, kidney disease, peptic ulcer, hyperthyroidism, and asthma.
Asthma Although theoretically the cold, dry, hypoxic mountain environment should worsen bronchoconstriction, there is little evidence of deterioration in practice. Asthmatics often find that they have less trouble at high altitude and this is likely to be related to the absence of allergens in the air and the reduced air density. They may also be helped by the increased sympathetic drive and production of corticosteroids at altitude. Patients should not ascend to altitude unless their asthma is stable. Travellers to remote places should take an emergency supply of steroids with them in case of deterioration.
In addition to warfarin, Sharma and Jusko (1) have listed a large number of other drugs with delays attributable to changes in mediator turnover. These range from H2-receptor antagonists, diuretics, and bronchodilators to corticosteroids, nonsteroidal anti-inflammatory drugs, and interferon.
Respiratory inadequacy may be due to disorders of the respiratory system such as asthma or pulmonary oedema. A decrease in the patient's respiratory drive may be due to central nervous system depression or decreased respiratory effort because of exhaustion or drugs depressing the patient's respiratory drive. In turn, the resulting hypoxia may have a direct effect on the heart by causing a bradycardia, which causes inadequate perfusion of the brain or heart and leads to cardiac arrest (Resuscitation Council UK 2000a). Cardiac abnormalities may be a primary or contributory cause of the cardiac arrest (see Table 11.2). Bronchospasm
Asthma 5.07 4.30 4.43 4.26 African American men and women also have a significantly higher prevalence of diabetes, as shown in Table 1.1. Asthma and stroke prevalence rates are also higher for African Americans as compared to Whites. African Americans have the highest cancer incidence of any racial or ethnic group in the United States. The incidence of cancer among African American men is about 525 per 100,000 compared to White men, who have about 450 per 100,000 cases. The age-adjusted incidence rates for all cancer sites combined was 20 higher for African American men than for White men. The cancer rates among African American women and White women are about the same, 325 100,000 and 340 100,000, respectively. However, the prognosis for cancer is poorer for African Americans when compared to that of Whites. For example, the 19831989 five-year relative survival rate for all cancer sites combined was 39 for African Americans and 55 for Whites. The lower survival rates
P2-Adrenoreceptor Mutations in Asthma Since the first descriptions of genetic polymorphisms in the P2 receptor that may play a pathogenic role in the development of asthma (83, 84), a number of investigators have shown an association between these mutations and patient response to treatment for this disease. A number of missense mutations within the coding region of the type 2 P-receptor gene on chromosome 5q31 have been identified in humans. In studies utilizing site-directed mutagenesis and recombinant expression, three loci at amino acid positions 16, 27, and 164 have been found to significantly alter in vitro receptor function. The Thr164Ile mutation displays altered coupling to adenylyl cyclase, the Arg16Gly mutation displays enhanced agonist-promoted down-regulation, and the Gln27Glu form is resistant to down-regulation (84). The frequencies of these various P2-adrenoreceptor (P2AR) mutations are no different in asthmatic than in normal populations, but Lima et al. (85) have...
The first report of the use of ACOM prodrugs to enhance the topical delivery of a parent drug containing an amide- or imide-like functional group was for 7-ACOM derivatives to deliver theophylline (Th) (Bodor and Sloan, 1977). The evaluation of only two members of the complete series (3 and 6) was reported initially (Sloan and Bodor, 1982). The characterization and evaluation of the complete series (1 to 6) was reported later (Table 1) (Kerr et al., 1998). The results were typical of what has been observed for most other ACOM derivatives of heterocyclic parent drugs containing amide- or imide-like functional group. All of the prodrugs were much more lipid soluble (increased SIPM) than Th, varying from 8 times for 1 to 75 times for 3 to 230 times for 5. Although in many series at least one member was more soluble in pH 4.0 buffer (increased S4.0) than the parent, in this series the best S4.0 values were 0.27 and 0.22 times that of Th for 1 and 3, respectively. The trend in solubilities...
Thea sinensis, Coffea arabica, and Theobroma cacao, and mention of the stimulating properties of these extracts is found in records of the most ancient civilizations. The active principles in these extracts are alkaloids called xanthines, the most potent being the-ophylline and caffeine. The effect of caffeine and theophylline on PDE activity was discovered soon after the discovery of cAMP. It was actually adopted as a diagnostic tool of activation of the cAMP-dependent pathway. Those cell functions that are potentiated by xanthines are most likely mediated by activation of the cyclic nucleotide pathway. More comprehensive studies have demonstrated that xanthines have additional effects on Ca2+ sequestration and on the adenosine pathway, but it is still accepted that a good portion of their stimulatory activity is due to the increase in cAMP that follows inhibition of the PDE activity. Treatment with xanthines produces a wide range of pharmacological effects, including stimulation of...
The psychiatric morbidity in acne (Gupta & Gupta, 2001b) is often the most important index of disease severity and often the most important factor in deciding whether or not to institute treatments for the acne, especially in the case of mild-to-moderate disease. The psychiatric morbidity in acne can be severe and comparable to the disability resulting from other chronic disorders such as diabetes and asthma (Mallon et al., 1999). In contrast to psoriasis, the severity of acne does not necessarily correlate with the severity of depression (Aktan et al., 2000 Yazici et al., 2004), as even mild-to-moderate acne has been associated with depression, suicidal ideation (Gupta & Gupta, 1998) and completed suicide (Cotterill & Cunliffe, 1997). Adolescent acne patients who experience problems at school or work and blame it mainly on their acne may be clinically depressed (Gupta et al., 1998). Treatment of both mild-to-moderate non-cystic acne (Gupta et al., 1990) and the treatment of cystic...
Guyatt et al. (1998) describe a cross-over trial of treatment for asthma. The multi-centre double-blind randomised trial recruited 140 patients. During the three periods in this cross-over study, each patient received salmeterol, salbutamol or placebo in random sequence. Patients completed the asthma-specific AQLQ. Two AQLQ scales were examined, asthma symptoms and activity limitations. Table 16.8 shows that the mean differences between salmeterol and the other two treatments were all statistically highly significant, but are small for AQLQ scores according to the classification of minimal clinically important difference in Section 16.5. The NNT is calculated from the proportion of patients who had obtained benefit from salmeterol, where better was defined as an improvement of 0.5, minus the proportion of patients who obtained a similar sized benefit from the alternative treatment. Thus in the first row of Table 16.8, these proportions are 0.42 and 0.12 for salmeterol versus...
As pointed out in Chapter 2, the process of drug distribution can account for both the slow onset of pharmacologic effect of some drugs (e.g., digoxin) and the termination of pharmacologic effect after bolus intravenous injection of others (e.g., lidocaine and thiopental). When theophylline was introduced in the 1930s, it was often administered by rapid intravenous injection to asthmatic patients. It was only after several fatalities were reported that the current practice was adopted of initiating therapy with a slow intravenous infusion. Nonetheless, excessively rapid intravenous administration of theophylline still contributes to the frequency of serious adverse reactions to this drug (21). The rapidity of carrier-mediated theophylline distribution to the brain and heart probably contributes to the infusion-rate dependency of these serious adverse reactions. changes in body fluid compartment volumes and protein binding also affect drug distribution in pregnant subjects. As...
Allegra L, Cogo A, Legnani D, Diano PL, Fasano V, Negretto GG (1995). High altitude exposure reduces bronchial responsiveness to hypoosmolar aerosol in lowland asthmatics. Eur Resp. J 8 1842-1846. 16. Dagg KD, Thomson LJ, Clayton RA, Ramsay SG, Thomson NC. (1997). Effect of acute alterations in inspired oxygen tension on methacholine induced bronchoconstriction in patients with asthma. Thorax 52(5) 453-7. 18. Denjean A, Roux C, Herve P, Bonniot J-P, Comoy E, Duroux P, Gaultier C. (1988). Mild isocapnic hypoxia enhances the bronchial response to methacholine in asthmatic subjects. Am. Rev. Respir. Dis. 138 789-793. Dillard TA, Rajagopal KR, Slivka WA, Berg BW, Mehm WJ, Lawless NP. (1998). Lung function during moderate hypobaric hypoxia in normal subjects and patients with chronic obstructive pulmonary disease. Aviat. Space Environ. Med. Oct 69(10) 979-85. Dosman JA, Hodgson WC, Cockcroft DW. (1991). Effect of cold air on the bronchial response to inhaled histamine in patients with...
Recognizing these processes, it is useful to distinguish between the pharmacologic action (e.g., stimulation of a receptor, inhibition of an enzyme), the physiologic effect (e.g., bronchodilatation, lowering of cholesterol), and the therapeutic response (e.g., relief of an asthma attack, reduction of risk of a cardiovascular event).
Fischer et al. reported on MRI of the brains of 10 subjects exposed to a simulated altitude of 4500 m for 10 hours after the administration of either a placebo, theophylline or acetazolamide 5 . Although 8 of the 10 subjects presented with moderate to severe AMS, there was no MRI of cerebral edema, irrespective of the medication taken. However, there was a moderate swelling of the brain, as indicated by a significant reduction of the inner cerebral fluid volume.
Observers, including health professionals, may tend to base their opinions of overall QoL upon physical signs such as symptoms and toxicity. However, in many disease areas, conventional clinical outcomes have been shown to be poorly correlated with patients' assessment of QoL. Thus, for example, in patients with asthma, Juniper et al. (1993) observed that correlations between clinical assessments and how patients felt and functioned in day-to-day activities were only modest.
When a disease is rapidly life threatening or markedly reduces quality of life, the distinction between professional and personal outcomes is often neglected. However, personal outcomes obviously should be addressed for many relatively asymptomatic ( silent ) diseases, especially those with a slow course and diseases in which symptomatic treatment may conceal a worsening of the underlying disease, such as asthma. Furthermore, even patients with extremely symptomatic or life-threatening diseases may choose not to treat them if they decide that the treatment would be worse than the disease, or even worse than dying, for them or their loved ones. menus planned by another. A schoolchild's need to use an asthma inhaler may be incompatible with his desire not to appear different, especially if school rules restrict his access, e.g., by requiring that medicines be left with the school nurse.
Juniper et al. (1993) evaluated the properties of the Asthma Quality of Life Questionnaire (AQLQ). Patients were assessed at enrolment and after 4 and 8 weeks. At each of the two follow-up times, patients were shown their AQLQ scores from their previous visit. After each study period, the patients were classified into those with stable asthma and those whose asthma changed. This classification was based upon both clinical assessment including lung function tests, and the patients' global rating of change in overall QoL. For both groups of patients, the mean change in each AQLQ scale was calculated. The changes in AQLQ scores were scaled to be from -7 (a very great deal worse) through 0 (no change) to +7 (a very great deal better). Table 3.16 shows the mean changes and SDs, and the results of a -test comparing the difference between the two change scores. The authors described as moderate the mean QoL change of 1.06 in those whose asthma changed. Not only was this value statistically...
Medication induced oesophageal injury was first reported in 19701, and was reviewed 198323. During the period between 1960 and 1983, 221 cases were reported due to 26 different medications, and since then there have been numerous reports in the literature24 25. Antibiotics account for half the reported cases regardless of brand, although it has been reported for numerous other drugs including emepronium bromide, theophylline, doxycycline monohydrate and bisphosphonates26. This may reflect the various proportions of drugs which are prescribed, but this has not been studied. Endoscopic surveillance in healthy volunteer studies has shown that oesophagitis is detectable in 20 of subjects taking non-steroidal anti-inflammatories (NSAIDs)27. NSAIDS are also believed to have a causative role in oesophageal stricture in patients with gastro-oesophageal reflux28.
Particular evaluation may be necessary for cardiovascular disease (e.g. angina pectoris, congestive heart failure, myocardial infarction), deep venous thrombosis, respiratory disease (e.g. asthma, chronic obstructive airways disease, emphysema), surgical conditions, cere-brovascular accident, epilepsy, psychiatric illness, diabetes and infectious disease.
Biflavones, tannic acid, phenylpropanes, and hyper-forin. Several of these chemical entities have been implicated in affecting the activity of metabolic enzymes or drug transporters. Hypericin induces CYP1A2 and thus may affect theophylline metabolism. Quercetin induces P-gp. St. John's wort interacts with indinavir, a protease inhibitor, via induction of CYP3A isoenzymes. St. John's wort also has been reported to decrease the concentration of cyclosporine, a CYP3A and P-gp substrate, in heart transplant patients (87). St. John's wort also decreases the concentration of digoxin, presumably because it induces P-gp, thus decreasing absorption and increasing excretion of this drug.
Even for a drug primarily eliminated by hepatic metabolism in nonpregnant women, the increase in GFR can significantly affect total drug clearance during pregnancy. For example, the renal clearance of theophylline, a drug largely eliminated by CYP1A2 metabolism, was found to increase during pregnancy so that its total elimination clearance was not
All patients who experience a cardiopulmonary arrest will have suffered some degree of hypoxia. Understanding the events leading up to the time of arrest will enable the team to discover whether it was the result of a primary cardiac event, such as a myocardial infarction, or whether it occurred at the end of a long period of physiological compensation. For example, the patient who experienced respiratory failure as a result of a severe exacerbation of asthma will present with the following signs and symptoms.
One of the major problems in running pediatric clinical trials is the availability of pediatric patients, who tend to be scattered, because they are numerically less likely to have diseases (other than asthma and the usual childhood illnesses). This affects the logistics of screening and subsequent clinic visits.
Narrowing of airways by mucus, inflammation or bronchial constriction can increase linear velocities of airflow, enhance inertial deposition and cause more deposition in the central airways. In adult respiratory distress syndrome, characterized by acute inflammatory oedema, the lung permeability to proteins increases and accumulation of fluid occurs. Lung deposition from MDI's was not found to be significantly different in asthmatics when compared to normals7 32, however a greater proportion of the dose was located more centrally in asthmatic subjects. This resulted in faster clearance of the drug as penetration into the lung is lessened33.
Content validity reflects the scientific validity of the rationale and how completely an indicator or a set of indicators represents that rationale. For example, does the measure represent only a few examples or the whole domain Consider the indicator above that refers to both asthma rescue and preventer medicine use. The content validity of this indicator is higher than it would be if it referred to only one or the other type of medicine, because it includes both of the two major epidemiological findings that connect asthma therapy with outcomes.
Complications of long-term ventilation. Inhaled steroids do not generate the same concerns in terms of their long-term effects, but have not been shown to be an effective treatment. Diuretics have been shown to have short-term effects on lung function measurements, but do not improve long-term outcome and increase the risk of nephrocal-cinosis. Bronchodilators (either inhaled or in the form of high-dose theophylline) have been advocated in children with CLD to treat bronchial smooth muscle hypertrophy and wheezing. There is, however, no convincing evidence for this practice and the wheezing is thought to be more likely due to an anatomically reduced airway diameter rather than pathologic bronchoconstriction. In summary, optimal nutrition and adequate oxygenation are the most effective treatments for CLD. Most infants will outgrow their oxygen requirement before they are ready to be discharged. A small number will continue to need longer-term oxygen. A child who is stable, is sucking...
Because you have asthma, you may have found some of the thing not much fun. We want you to think about all the things that you do in ' your asthma. Some people are bothered by asthma when doing through the list. Think about how your asthma has On the next page, write down the three (3) thii your asthma during the last week. These regularly during the study. The three ai think of other activities as long as you On the next page, write down the three (3) thii your asthma during the last week. These regularly during the study. The three ai think of other activities as long as you APPENDIX Ell PAEDIATRIC ASTHMA QUALITY OF LIFE Page 2 of 2 QUESTIONNAIRE (PAQLQ) EXTRACT ONLY On the lines below, please write down the 3 activities in which you have been bothere most by your asthma. We then want you to tell us how much you have been botheR doing these things during the last week because of your asthma.
A 20-year-old man is hospitalized after an asthmatic attack precipitated by an upper respiratory infection and fails to respond in the emergency room to two subcutaneously injected doses of epinephrine. The patient has not been taking theophylline-containing medications for the past 6 weeks. He weighs 60 kg and you estimate that his apparent volume of theophylline distribution is 0.45 L kg. Bronchodilator therapy includes a 5.6-mg kg loading dose of aminophylline, infused intravenously over 20 min, followed by a maintenance infusion of 0.63 mg kg per hour (0.50 mg kg per hour of theophylline). Forty-eight hours later, the patient's respiratory status has improved. However, he has nausea and tachycardia, and his plasma theophylline level is 24 xg mL.
Exposure to airborne contaminants can result in a variety of acute and chronic toxic effects in the respiratory system, including irritation, aggravation of preexisting conditions (e.g., asthma), structural damage leading to chronic diseases (e.g., pulmonary fibrosis and emphysema), and cancer. For example, the effects of inhaling gases such as Cl2, SO2, and H2S which are subject to accidental and routine release to the environment range from coughing to difficulty in breathing to death, depending on the exposure. Ozone aggravates asthma and increases the severity of respiratory infections. Particulate matter, asbestos, arsenic, and nickel are known lung carcinogens.
Some attempts have been made to label the drug itself. A bronchodilator, the anticholinergic compound ipratropium bromide, has been labelled using a cyclotron-produced radionuclide 77Br. This radionuclide has a half-life of 58 hours with peak gamma-ray energies, 239 and 521 KeV which are not ideal but are usable for scintigraphic studies. The powder produced was incorporated into pressurized canisters and it was shown that upon actuation, radioactivity was lost from the canisters at a rate equal to that of the drug22.
Asthma, COPD. bronchiectasis (permanent dilation of airways with obliteration by secretions, infections, fibrosis), tumor or foreign body Hyperinflation (COPD. asthma) predictors of CHF h o CHF. PND. S). CXR w venous congestion. AF ama 2005 294 1944) dyspnea w nl CXR CAD. asthma. PE. PHT. early ILD. anemia, acidosis. NM disease Bronchodilator indicated if obstruction at baseline or asthma clinically suspected Methacholine challenge helps dx asthma if spirometry nl. 20 i FEN asthma Asthma ILD Hemorrhage CHF Polycythemia t Pulm blood vol. (e.g obesity, mild CHF. L- R shunts)
RSNO has been implicated in a number of respiratory diseases. In ammatory state as in pneumonia gives higher RSNO levels in the lungs. Asthmatic patients exhale high levels of NO but have depressed RSNO levels in the airways. The modulation of RSNO status for clinical therapy is only now being considered 66,70,135 .
Up to 10 of the travelling population have atopic conditions, such as eczema or asthma, which cause a raised eosinophil count, and some medications such as nonsteroidal anti-inflammatory agents also cause a raised count. A wide variety of nematode and trematode infections produce eosinophilia, particularly during the migratory phases of larvae through the body (Table 12.12). Some of these, such as hookworms, roundworms and Strongyloides spp are universally distributed in the tropics, while other parasitic infections will be suggested by the specific travel history of the patient and by the symptoms and physical findings.
Various target organs may be involved in the immune response, but this usually depends on the type of reaction rather than on the distribution of the foreign substance. The many substances which cause immune responses may cause anaphylactic reactions giving rise to asthma and various other symptoms as described above. The site of exposure to the foreign compound may not necessarily be the lungs, however. Similarly, a common immune response is urticaria, or the formation of wheals on the skin which can occur when exposure has been via the oral route. Thus, the target organ is generally due to the particular response rather than the circumstances of exposure or distribution of the compound. However, there are exceptions to this such as the type IV cell-mediated immune reactions where the cell is altered by the foreign compound and is then a target. In the case of halothane hepatitis the liver is the target for metabolic reasons (see Chapter 7 for more detail). Another exception is the...
With increased elastic resistance, the work of breathing increases. The patient can try to compensate either by increasing the tidal volume or by breathing faster. When breathing difficulty is due to increased elasticity of the lungs or chest wall, the patient tends to compensate mainly by breathing faster, as it is too much work to deeply inspire. When it is resistance to flow that is increased, as occurs in the narrowing of the respiratory passages in asthma and chronic bronchitis, the patient often finds it less work to compensate by increasing the tidal volume rather than the rate. In fact, the rate of breathing may decrease. One of the simplest ways to assess respiratory function is to have the patient inspire maximally to total lung capacity and then to expire fully as rapidly as possible. The total volume of the expired air (the vital capacity) is low in restrictive lung disease, where expansion of the lung is restricted (respiratory compliance is low elastic rebound is high),...
A second phobia was fear of suffocation, which was apparently caused by a bad case of whooping cough, chronic childhood asthma, and an older brother who used to tease Beck by putting a pillow over his face. Beck's fear of suffocation also emerged in the form of a tunnel phobia he would feel tightness in his chest and have difficulty breathing while driving through a tunnel. In addition he developed fears of heights and of public speaking. He maintains that he was able to resolve these fears by working them through cognitively. Beck also drew from his own experiences when writing his first book on depression, which he published in 1967. Beck was mildly depressed while he was writing the book, but regarded the project as a kind of self-treatment.
Pulmonary function should be optimized prior to and during flight by using bronchodilators and or corticos-teroids, if indicated. If oxygen is required, provide the airline with at least 48 h notice prior to scheduled departure. A prescription for oxygen (indicating the flow rate or Fio2, and specifying continuous versus intermittent oxy-gen)2 is required, as is a physician's letter outlining the individual's fitness to travel. Inflight oxygen and equipment will be supplied by the carrier, at a cost to the traveler, usually based on flight segments and or the number of oxygen canisters required. Check with the air carrier for charges, and be aware that delivery systems
As a result of poverty and drug abuse, prisoners have a uniquely high prevalence of communicable disease, including HIV AIDS, tuberculosis, sexually transmitted diseases, and viral hepatitis B and C (NCCHC, 2002) owing in part to their drug abuse. As a result of their poverty, inmates have high rates of mental illness and chronic diseases, such as asthma, diabetes, and hypertension. Drug addiction, poor access to health care, poverty, substandard nutrition, poor housing conditions and homelessness contribute to increased morbidity from these and other debilitating conditions.
FIGURE 18.10 Correlation between concentration effect at the tissue level measured by EC50 for relaxation of guinea pig trachea and concentration effect at the receptor level for (A) antagonism of the A1-adenosine receptor and (B) inhibition of phosphodiesterase for a series of xanthine analogs, including theophylline. The correlation between EC50 for tracheal relaxation and IC50 for phosphodiesterase inhibition suggests that phosphodi-esterase inhibition is the primary site of action for the antiasthmatic effects of these drugs. (Reproduced with permission from Brackett LE, Shamim MT, Daly JW. Biochem Pharmacol 1990 39 1897-904.)
Medical conditions that often create problems include asthma, chest trauma, diabetes mellitus, head injury, epilepsy, cardiovascular disease and decompression illness. Each of these conditions and their implications with regard to diving will be discussed. Asthma Normal lung function is required by all divers, both to enable them to achieve adequate work capacity and to ensure that their lungs can accommodate the pressure and volume changes that occur during diving. Failure to accommodate these changes in pressure and volume can result in lung rupture, which may manifest as interstitial emphysema, pneumothorax or arterial gas embolism. Whereas interstitial emphysema may be no more than uncomfortable, the development of a pneumothorax or arterial gas embolism in a diver can be life threatening. Individuals with asthma are known to be at increased risk of lung rupture (Light, 1994), even under normobaric conditions 5.4 of a group of 479 children admitted during an asthmatic episode were...
Coping with Asthma
If you suffer with asthma, you will no doubt be familiar with the uncomfortable sensations as your bronchial tubes begin to narrow and your muscles around them start to tighten. A sticky mucus known as phlegm begins to produce and increase within your bronchial tubes and you begin to wheeze, cough and struggle to breathe.