Inhaled and oral salbutamol in exercise-induced asthma

Twenty-one asthmatic patients participated in a single blind, crossover study comparing the effects of aerosol and oral salbutamol (a beta-adrenergic bronchodilator), on exercise-induced bronchospasm. By both routes of administration, salbutamol (albuterol) produced significant bronchodilatation at rest, but only the aerosol effectively prevented post-exercise bronchospasm in most patients. Because exercise-induced bronchospasm is a common problem in children and adults with asthma, these observations are relevant to the drug therapy of these patients. The existence of separate mechanisms for bronchodilatation and the prevention of exercise-induced asthma is postulated. It is possible that differing tissue concentrations of salbutamol are responsible for the observed differences between the 2 routes of administration.     

Dose equivalence and bronchoprotective effects of salmeterol and salbutamol in asthma

BACKGROUND: Salbutamol is the most widely prescribed short acting beta 2 agonist and salmeterol is the first long acting inhaled beta 2 agonist. The dose equivalence of salmeterol and salbutamol is disputed. Estimates of weight-for-weight dose ratio have ranged from 1:2 to 1:16. A study was undertaken to clarify the true dose ratio. METHODS: The bronchoprotection afforded against repeated methacholine challenge by inhaled salmeterol 25 micrograms and 100 micrograms and salbutamol 100 micrograms and 400 micrograms was compared in a randomised, double blind, placebo controlled, crossover trial. Subjects were 16 stable asthmatics with a baseline forced expiratory volume in one second (FEV1) of > or = 65% predicted, screening concentration provoking a fall in FEV1 of 20% (PC20FEV1) of < or = 8mg/ml, and a shift in PC20FEV1 of more than two doubling concentration steps following inhalation of salbutamol 400 micrograms. On five separate occasions subjects underwent methacholine challenge before and 30 and 120 minutes after drug administration. PD20FEV1 was calculated for each challenge. FEV1 at 90 minutes after drug administration was also recorded. RESULTS: Bronchoprotection afforded by salmeterol was increased at 120 minutes compared with 30 minutes and protection by salbutamol was decreased. Protection by both doses of salmeterol was similar to salbutamol 100 micrograms at 30 minutes but significantly greater at 120 minutes. FEV1 at 90 minutes was significantly greater after salmeterol 100 micrograms than after placebo, but there were no other significant differences between treatments. Maximal observed protection was equivalent for salmeterol 100 micrograms and salbutamol 400 micrograms. CONCLUSIONS: The data are compatible with a weight-for-weight dose ratio for salmeterol:salbutamol of < or = 1:4.     

Acute asthma in adults

Acute asthma can be defined as first appearance of asthma or as a rapid deterioration of the asthmatic's habitual condition which can develop into a life-threatening condition. The severity of an attack and the effect of treatment has to be evaluated with the aid of peak flow measurements. The patient's self-treatment consists of increasing the dose of inhaled beta-2-receptor agonist and eventually doubling the dose of inhaled steroids. First-line treatment in hospital is high-dose inhaled nebulized beta-2-receptor agonist and oral corticosteroids. Ipratropium bromide and theophylline infusions may be added if necessary.     

Hypokalaemia following nebulized salbutamol in children with acute attack of bronchial asthma

OBJECTIVE: To determine whether use of nebulized salbutamol therapy for treatment of an acute attack of asthma in children is associated with hypokalaemia and if so what is its frequency, severity and effect on recovery. METHODOLOGY: Forty-six children, aged 10 months to 12 years (mean 7.9 +/- 1.5 years) with acute attack of bronchial asthma, treated initially with three doses of nebulized salbutamol 0.15-0.3 mg/kg, every 30 min participated in the study. Blood for serum potassium was obtained at the beginning and after three doses of nebulized salbutamol therapy, before administering other drugs. RESULTS: The mean +/- SD serum potassium level decreased marginally from 3.9 +/- 0.5 mEq/L to 3.7 +/- 0.5 mEq/L (P < 0.05). A decrease in serum potassium concentration was noted in 26 (56.5%) and hypokalaemia (serum potassium < 3.5 mg/L) in 17 (39%) patients. It was more frequent in patients who had received oral salbutamol for the preceding 7 days. The average time taken for recovery was longer in patients who had hypokalaemia than those who had normal serum potassium concentration (8.6 +/- 2.7 h vs 6.5 +/- 2.7 h; P < 0.005). CONCLUSIONS: Hypokalaemia may occur in about one-third of patients treated with three doses of nebulized salbutamol therapy, especially those on prior oral salbutamol therapy. The monitoring of serum potassium concentration may be warranted in such patients.     

Acute asthma epidemics, weather and pollen in England, 1987-1994

Recent epidemics of acute asthma have caused speculation that, if their causes were known, early warnings might be feasible. In particular, some epidemics seemed to be associated with thunderstorms. We wondered what risk factors predicting epidemics could be identified. Daily asthma admissions counts during 1987-1994, for two age groups (0-14 yrs and > or = 15 yrs), were measured using the Hospital Episodes System (HES). Epidemics were defined as combinations of date, age group and English Regional Health Authority (RHA) with exceptionally high asthma admission counts compared to the predictions of a log-linear autoregression model. They were compared with control days 1 week before and afterwards, regarding seven meteorological variables and 5 day average pollen counts for four species. Fifty six asthma epidemics were identified. The mean density of sferics (lightning flashes), temperature and rainfall on epidemic days were greater than those on control days. High sferics densities were overrepresented in epidemics. Simultaneously high sferics and grass pollen further increased the probability of an epidemic, but only to 15% (95% confidence interval 2-45%). Two thirds of epidemics were not preceded by thunderstorms. Thunderstorms and high grass pollen levels precede asthma epidemics more often than expected by chance. However, most epidemics are not associated with thunderstorms or unusual weather conditions, and most thunderstorms, even following high grass pollen levels, do not precede epidemics. An early warning system based on the indicators examined here would, therefore, detect few epidemics and generate an unacceptably high rate of false alarms.     

A comparison of the clinical efficacy and patient acceptability of terbutaline Turbuhaler and salbutamol Rotahaler, in adult patients with asthma

Fifteen Thai patients with Parkinson's disease (7 females, 8 males) were enrolled in an open label trial of pergolide (a new dopamine agonist) to evaluate its safety and efficacy. Inpatients and outpatients from Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand from 1992 to 1994 were included in the study with a total duration of 18 weeks. Both de novo patients and patients who were being treated with levodopa without dopamine agonist and were obtaining a less than optimal response at both visit 1 and visit 2 were all enrolled in this study. At entry into the study, 3 patients had Hoehn and Yahr stage I, 7 patients at stage II, 3 patients at stage III, and 2 patients at stage IV. Pergolide dosage was gradually built up until an optimal dosage was achieved. The average dose of pergolide during the study was 0.94 mg/day (range 0.075 to 8 mg/day). All patients completed the study and no patients dropped out. Two patients (13.33 per cent) experienced nausea (on 0.4 mg/day and 0.075 mg/day), two patients (13.33 per cent) experienced sleepiness (0.50 mg/day and 0.075 mg/day) and one patient (6.67 per cent) unsteadiness on walking (0.50 mg/day). There was one patient who required pergolide up to 8 mg/day which is higher than the recommended dosage (5 mg/day) but this patient experienced no adverse effects and his disabled dyskinesic was abolished. Our study demonstrated the good toleration and efficacy of pergolide treatment for Thai patients with Parkinson's disease. This new dopamine agonist stimulates both D1 and D2 receptors in comparison to other dopamine agonists (bromocriptine and lisuride) which stimulate only D2 receptors.     

Bronchodilator response to salbutamol after spontaneous recovery from nonspecific bronchial provocation tests in asthma

Assessment of airway responsiveness by bronchoprovocation and bronchodilatation tests is important in the diagnostic work-up protocol of bronchial asthma and it would be convenient to undertake both tests on the same occasion. However, it is not known whether this can be done accurately. Therefore, this study evaluated the effect of a prior bronchial provocation test on the bronchodilator response to salbutamol after spontaneous recovery of the forced expiratory volume in one second (FEV1) in a group of asthmatic subjects. On two separate occasions at the same time of day, concentration-response studies with inhaled histamine or methacholine, or a sham challenge with normal saline were carried out in a blinded, randomized manner. Changes in airway calibre were followed as FEV1 and agonist responsiveness expressed as the provocative concentration causing a 20% fall in FEV1 (PC20). After either spontaneous recovery or a fixed-duration wait of 45 min (when appropriate), the subjects received 2x100 microg of salbutamol from a metered dose inhaler with a spacer. The bronchodilator response to salbutamol was expressed as a percentage of initial FEV1 (deltaFEV1% init). Bronchial challenge with both agonists failed to alter significantly the airway response to salbutamol, with the deltaFEV1% init mean value (range) being 16.9% (9.0-31.9) and 17.5% (11.6-31.2) on the sham and histamine/methacholine challenge day respectively. It was shown that the degree of bronchodilatation achieved after salbutamol 200 microg is not affected by prior bronchoprovocation testing when enough time is allowed for the airways to recover spontaneously to baseline forced expiratory volume in one second. Thus evaluation of airway responsiveness by both bronchial provocation tests and bronchodilator testing can be assessed reliably within a few hours in asthmatic patients.     

Acute management of severe childhood asthma

Severe childhood asthma is a serious, life-threatening disease that presents a challenge for patients, families, and caregivers. Despite evolving medical and pharmacologic therapies, the incidence and severity of asthma are increasing. Vasoactive substances are released in response to environmental and intrinsic triggers and result in bronchospasm, bronchial mucosal edema, and mucus plugging of the airways. Early recognition of symptoms and prompt, aggressive treatment, including oxygen, beta agonists, corticosteroids, and anticholinergic agents, are essential in halting the progression of asthma symptoms. In the most severe cases, intubation, mechanical ventilation, and treatment with anesthetic agents may be needed to avoid significant morbidity and mortality. This article reviews epidemiology, pathophysiology, and acute care of the child experiencing an acute asthma exacerbation.     

Duration of action of formoterol and salbutamol dry-powder inhalation in prevention of exercise-induced asthma in children

The aim of this study was to evaluate the effect and tolerability of formoterol 12 micrograms on exercise-induced asthma in children for 12 h as compared to the effect of salbutamol 400 micrograms and placebo. The drugs were inhaled as dry powder from a flow-dependent metered-dose inhaler (DP-MDI). Sixteen asthmatic children took part in a double-blind placebo-controlled within-patient single-centre trial. On each study day the patients were given one of the drugs or placebo in random order, and standardized exercise tests were performed after 3 and 12 h. At a pretrial test the children had demonstrated a median maximum percentage fall of 38% (range 22-79%) in forced expiratory volume in 1 s after exercise challenge. Formoterol showed a median percentage protection of 77% and 70% at 3 and 12 h postexercise, respectively, as compared to 46% and 13% with salbutamol. No side-effects were observed. Formoterol 12 micrograms administered as dry powder offers significantly better protection against exercise-induced asthma after 3 and 12 h as compared to salbutamol 400 micrograms and placebo.     

APGAR scores, respiratory distress syndrome and salbutamol

In parallel studies at St Mary's Hospital, Portsmouth, in which women presenting in premature labour at 20 to 36 weeks' gestation were treated with salbutamol by mouth (208 women) or by parenteral administration (20 women), the prevention of low apgar scores was significant (P less than 0.01) if the dose-delivery interval was less than four hours and the prevention of respiratory distress syndrome (RDS) was significant (P less than 0.05) if the dose-delivery interval was less than three hours.     

Acute hyperglycaemia causes severe disturbances of mesenteric microcirculation in an in vivo rat model

BACKGROUND: Chronic hyperglycaemia in diabetes is suggested to be a major cause of diabetic angiopathy. Up until now, the effects of acutely induced hyperglycaemia in non-diabetic subjects as well as hyperglycaemic effects in early diabetes, on mesenteric microcirculation and leucocyte endothelial cell interaction have not been investigated extensively. METHODS: The aim of this study was to examine rat mesenteric microcirculatory parameters such as leucocyte adhesion, leucocyte emigration, venular shear rate and leucocyte rolling velocity using a new rat model both with continuous venous glucose infusion and with continuous arterial measurement of blood glucose concentration while observing mesenteric microcirculation with in vivo capillary microscopy in the non-diabetic and diabetic state. RESULTS: In normal non-diabetic rats, acute elevation of glucose concentration resulted in a highly significant, rapid and step-by- step enhancement of adhesion and emigration in a dose dependent manner. Leucocyte rolling velocity was reduced with rising glucose levels. Venular shear rate showed a similar reduction at all hyperglycaemic levels. In streptozotocin-induced diabetes, adhesion and emigration were significantly enhanced while shear rate and leucocyte rolling velocity were severely reduced, resembling the effects of glucose infusion experiments. Longer duration of diabetes resulted in a further enhancement of leucocyte adhesion and reduction of leucocyte rolling velocity while emigration and shear rate were not influenced by a longer period of diabetes manifestation. CONCLUSION: Experiments using different mannitol concentrations revealed that most of the observed glucose effects can be mimicked by mannitol and are therefore - at least in part - due to changes in osmolarity by yet unknown mechanisms.     

Cumulative dose-response study of non-CFC propellant HFA 134a salbutamol sulfate metered-dose inhaler in patients with asthma

STUDY OBJECTIVE: This study compares the safety and efficacy of HFA 134a salbutamol sulfate (Airomir in the 3M CFC-free system [3M Pharmaceuticals]) and CFC 11/12 salbutamol (Ventolin [Allen & Hanburys]) in a cumulative dose-response (1, 1, 2, 4, 8 inhalations at 30-min intervals) study in asthmatic patients. DESIGN: Randomized, single-blind, two-period cross-over study. PARTICIPANTS: Twenty-four stable mild to moderate asthmatics. MEASUREMENTS AND RESULTS: At all cumulative inhalations, the changes in FEV1 (absolute, percent, and percent predicted) and FVC were equivalent. There was also no significant difference in heart rate, serum potassium level, BP, 12-lead ECG, Holter monitor recordings, or adverse events. Both HFA 134a salbutamol sulfate and CFC 11/12 salbutamol displayed a significant dose-response for FEV1, FEF25-75%, FVC, serum potassium, heart rate, and systolic BP. CONCLUSIONS: HFA 134a salbutamol sulfate and CFC 11/12 salbutamol produced clinically and statistically similar airway responses and side effects. These results indicate that HFA 134a salbutamol sulfate would be a safe and effective substitute for CFC 11/12 salbutamol.     

Acute asthma: treatment and outcome of 2000 consecutive pediatric emergency room visits in Doha, Qatar

Caring for a "difficult patient" is a concern frequently communicated among nurses and reported in the clinical and research literature. A theoretical perspective explaining the phenomenon of difficult patients is proposed and is based on a reformulation of propositions from labeling theory and the concept of social deviance. Applications to nursing practice focus on patient characteristics judged as deviant by nurses, communication of the deviant label, and exclusionary and inclusionary reactions to perceived patient deviance.     

Randomized controlled trial of ipratropium bromide and frequent low doses of salbutamol in the management of mild and moderate acute pediatric asthma

The standardized enzyme-linked immunosorbent assay (ELISA) for measurement of serum immunoglobulin G (IgG) antibody responses to meningococcal C polysaccharide has been modified to employ assay conditions that ensure specificity and favor detection primarily of high-avidity antibodies. The modified and standard assays were used to measure IgG antibody concentrations in sera of toddlers vaccinated with meningococcal polysaccharide vaccine or a meningococcal C conjugate vaccine. The results were compared to the respective complement-mediated bactericidal antibody titers. In sera obtained after one or two doses of vaccine, the correlation coefficients, r, for the results of the standard assay and bactericidal antibody titers were 0.45 and 0.29, compared to 0.85 and 0.87, respectively, for the modified assay. With the standard assay, there were no significant differences between the geometric mean antibody responses of the two vaccine groups. In contrast, with the modified assay, 5- to 20-fold higher postvaccination antibody concentrations were measured in the conjugate than in the polysaccharide group. Importantly, the results of the modified assay, but not the standard ELISA, paralleled the respective geometric mean bactericidal antibody titers. Thus, by employing conditions that favor detection of higher-avidity IgG antibody, the modified ELISA provides results that correlate closely with measurements of antibody functional activity that are thought to be important in protection against meningococcal disease.     

Acute bronchial asthma associated with the administration of ophthalmic indomethacin

A life-threatening episode of bronchial asthma may follow treatment by ophthalmic indomethacin. This case report describes an elderly man who experienced a serious attack of bronchial asthma after receiving ophthalmic indomethacin solution for aphakic cystoid macular edema, following extracapsular cataract extraction.     

Prolonged hypoxaemia after nebulised salbutamol

Pulse oximetry is increasingly used to assess hypoxaemia in respiratory illnesses. Six children presenting with acute asthma and prolonged falls in oxygen saturation values after treatment with salbutamol are described who were subsequently shown to have pneumonic consolidation on chest radiography.     

Occupational asthma, IgE and IgG

Cyproheptadine is an antihistamine and serotonin antagonist given to children for allergies, migraine headaches, and growth problems. A 5-year-old boy began to have episodes of violent behavior after the initiation of cyproheptadine therapy. After cyproheptadine was discontinued, the aggression ceased over the course of a few weeks. Although there are other causal explanations possible in this case, cyproheptadine seems the most likely cause of the violent behavior, especially in view of the literature on the relation between serotonin and aggression.