[Chronic asthma in children: comparison between a delayed-action theophylline preparation and a prompt-release aminophylline preparation]

Data from 34 patients were included in the analysis of this open group comparative study comparing a controlled release theophylline given twice daily with immediate release aminophylline given four times daily. The treatment period was of eight weeks duration. There was no significant difference between treatments in clinical assessments of asthma severity or pulmonary function tests. Similarly there were no significant differences between treatments in diary card assessments of asthma symptoms or PERF. Serum theophylline levels were measured prior to the morning dose of test treatment and 2 or 5 hours later, respectively for patients taking immediate release (IR) or controlled release (CR) preparations, at each clinic visit. There was no significant difference between treatments in serum theophylline levels fluctuations, although the dosing interval (12 hours) was twice as long for CR formulation. Six patients reported unusual symptoms, two in the CR group (headache, gastric discomfort) four in the aminophylline group (three headache, one headache and vomiting).

Aminophylline treatment of preterm labor

Prevention of neonatal mortality linked to prematurity may be achieved by treating preterm labor, thus allowing fetal lungs to spontaneously develop, or by administering drugs able to enhance pulmonary maturation. The methylxantine derivative aminophylline has been reported to reduce uterine contractility and increase the concentrations of saturated phosphatidylcholine in fetal lungs. Its effectiveness in treating preterm labor and preventing respiratory distress syndrome (RDS) has been evaluated in comparison to the widely used drug ritodrine. In 39 pregnant women with preterm labor the efficacy of aminophylline and ritodrine in delaying the delivery seemed similar. However, while two of the babies born from ritodrine treated mothers died because of RDS, all babies born from aminophylline-treated mothers survived. These data might then confirm the effectiveness of aminophylline treatment to prevent RDS.

Anaphylaxis

The clinical syndrome of anaphylaxis may be produced by a number of mechanisms. The life-threatening clinical features are angioneurotic oedema, bronchospasm, cardiovascular collapse and pulmonary oedema. The initial treatment consists of general resuscitation plus adrenaline. In shock, colloid solutions should be used to restore blood volume. The pulmonary oedema that occurs is a membrane oedema, and should be treated with artificial ventilation, positive end expiratory pressure, and volume replacement. After a reaction, all available tests should be used to determine the cause, and the patient should be given a warning letter describing the evidence for attributing his reaction to the determined cause. (This should be done in addition to the provision of any identification bracelet.) Pharmacological pretreatment is a valid preventive manoeuvre, but is not 100% reliable.

Dose-dependent kinetics of theophylline in adults with pulmonary diseases

The incidence of dose-dependent pharmacokinetics of theophylline was retrospectively investigated in adults with pulmonary disease receiving continuous aminophylline infusions. Twenty-one of 180 successive admissions to medical intensive care units with a diagnosis of chronic obstructive pulmonary disease, asthma, or respiratory failure met the criteria of two steady-state serum theophylline concentrations on two different doses. Of these, 14 patients continued to smoke, whereas 7 had never smoked or had stopped greater than 1 year prior to admission. No statistical difference existed between the mean systemic clearances of theophylline at the two different doses, using either total body weight or ideal body weight. Only 1 of the 21 patients met the criteria for dose dependency of a greater than or equal to 50% reduction in clearance with dosage increase. Six of eight subjects with decreased clearance on the higher dose were nonsmokers. In contrast, all nine with augmented clearance following dosage increase were smokers. Four were considered to have proportional changes. In general, nonsmoking patients tended to have greater changes in serum theophylline concentration than in dosage. Conversely, smoking patients demonstrated smaller changes in concentration. The relationship of smoking status and dose-dependent theophylline elimination is discussed.

Influence of ambient temperature and drug treatments on brain oedema induced by impact injury on skull in rats

The progression and persistence of oedema development following impact-injury on closed skull was studied in anaesthetised as well as in unanaesthetised rats. The degree and rate of oedema development, following trauma, was aggravated in anaesthetised hypothermic animals but was reduced/or delayed by maintenance of body temperature at euthermic level. In general, the unanaesthetised animals showed a greater accumulation of oedema fluid than the corresponding anaesthetised group. The development of oedema corresponded more or less with the accumulation of 5-HT level in plasma and brain. This development of oedema was completely prevented following pretreatment with p-CPA, indomethacin paracetamol and aminophylline in unanaesthetised animals; whereas these drugs were able only to partially reduce the oedema development in euthermic anaesthetised animals. On the other hand the cyproheptadine pretreatment aggravated the oedema development which was more pronounced in unanaesthetised animals. The probable mechanism of the action of these drugs has been discussed.

[Role of prostaglandins in the pathogenesis of bronchial asthma in children and possibilities in therapeutic treatment]

During the past few years, in relation to study of prostaglandins, biochemical active lipids recently identified, a large quantity of physiological and pathological processes involving these compounds have been described. Convincing data confirm the regulation of the tone of smooth trachea and bronchial muscles by these substances. In this sense and within the pathological states of the respiratory system, bronchial asthma is of special interest. Recently, a detailed description of the pathogenesis of bronchial asthma, and particularly of this atypical form, has been investigated. Classic mediators of anaphylaxis, such as histamin, SRS-A, serotonin, acetylcholin, etc., have important roles in the pathogeny. Fewer works, however, have been dedicated to the study of prostaglandins and the results obtained are often contradictory. In this study, the importance of prostaglandins E, F-2 alpha, A and B are investigated in 84 patients with a diagnosis of bronchial asthma. Their ages varies between 2 and 11 years. 51 suffered from the atypical form, 11 from infectious form and 22 the mixed form. To diagnose each case, detailed anamnesis and clinical tests were carried out as well as cutaneous tests with non bacterial and fungous allergens. The RAST technique and total levels of IgE were also used. The control group of 45 children were studied in the same way. With regard to the results obtained, during the intercrisis period a rise in PGF2-alpha and a decrease in PGE could be observed. During the crisis period, an even greater rise in the concentration of PGF2-alpha and a lesser of increase of PGE were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of methylprednisolone on sputum biochemical components in asthmatic bronchitis

Nineteen patients with chronic mucus hypersecretion and reversible airway obstruction were studied during an acute exacerbation. One group of patients was treated with antibiotics and aminophylline, the other, additionally, with gradually decreasing doses of methylprednisolone, starting with 80 mg/day. The sputum specimens were collected on the day of admission and 2 weeks later. In whole sputum, we examined macromolecular components both transudated from serum and locally secreted: albumin, fucose, N-acetylneuraminic acid, total protein, IgA, IgM, IgG. At the end of the second week albumin (marker of serum transudate), and fucose (marker of mucus glycoproteins), were significantly lower in the group treated with corticosteroids. IgG and albumin behaved in the same way suggesting a marked IgG serum exudation. IgM was partially reduced by corticosteroids while IgA remained unchanged.

Drug treatment in acute asthma

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Intravenous aminophylline in the treatment of acute bronchospastic exacerbations of chronic obstructive pulmonary disease

Often chronic obstructive pulmonary disease (COPD) patients treated for acute exacerbations receive intravenous (IV) aminophylline in addition to inhaled bronchodilators that may raise serum levels of theophylline into the toxic range. A double-blind, randomized study of 52 men with COPD who came to the emergency department for treatment of exacerbations was initiated to establish the efficacy and safety of this common practice. After history and physical examination, patients were treated with 28% oxygen by Venturi mask and 0.3 cc metaproterenol sulfate in 2.5 cc saline by nebulizer; an IV line was started and patients received either aminophylline or D5W. Measurements included baseline and two-hour serum theophylline levels, pulmonary function tests, and symptom questionnaires. Mean values from the entire group showed decreases in respiratory rate, cardiac rate, and pulsus paradoxus, and increases in forced expiratory volume in one second (FEV1) and vital capacity (VC) over a two-hour treatment period (P less than .01). Despite the increase in serum theophylline in the treatment group, the demographic, clinical, pulmonary function, and outcome data were found to have no statistically significant differences when compared to control patients. The data were then analyzed according to serum theophylline levels. Theophylline level greater than 20 micrograms/mL occurred in 15 patients with no untoward effects; premature ventricular contractions (PVCs) were no more frequent in this group than in those with lower serum theophylline levels. A theophylline level greater than 10 micrograms/mL after two hours of treatment resulted in the following differences, which were not statistically significant: mean FEV1 response less than or equal to 10 micrograms/mL vs greater than 10 micrograms/mL, 20% vs 28%; mean VC change, 17% vs 30%; or mean emergency department returns in one week, 0.1 vs 0.26. In our experience, oxygen and inhaled metaproterenol are effective treatment for exacerbations of COPD.

Idiopathic apnoea of prematurity treated with doxapram and aminophylline

Doxapram infusion was given to five preterm infants in whom therapeutic concentrations of theophylline had failed to control episodes of apnoea. Doxapram successfully controlled the apnoea, the arterial blood PCO2 value decreased significantly, and no side effects were reported.

[Changes in plasma nonesterified fatty acids and blood glucose in the newborn infant in therapy with aminophylline]

We investigated the effect of intravenous infusions of aminophylline on plasma glucose and nonesterified fatty acid (NEFA) levels in 14 newborns with apnea (mean birthweight: 2.514 +/- 866 g; mean gestational age: 34.8 +/- 3.94 weeks). Theophylline apparent volume of distribution was 0.55 liters per Kilogram and the half-life was major than 12 hours. It was found that theophylline caused pronounced and prolonged lipid mobilization, as measured by the plasma NEFA. The ability of theophylline to induce a rapid rise in blood glucose was confirmed. Elevation in plasma NEFA might be an important factor in facilitating the competition with bilirubin for binding sites of albumin and the development of arrythmias in newborns with acute myocardial injury.

Effects of aminophylline on diaphragmatic fatigue during acute respiratory failure

The effects of aminophylline on diaphragmatic fatigue and recovery in the face of hypoxemia and hypercapnic acidosis were studied in anesthetized, spontaneously breathing, dogs. The phrenic nerves were stimulated supramaximally at 10, 20, 50, and 100 Hz during 2 s with electrodes placed around the fifth roots, and the resulting transdiaphragmatic pressure (Pdi) was measured with balloon catheters. The dogs were occluded before the stimulations at functional residual capacity. The latter was monitored by measuring the end-expiratory transpulmonary pressure, which remained constant throughout the experiment. Diaphragmatic fatigue was produced by resistive loaded breathing. At the end of the runs, which lasted 15 +/- 2 min, all the dogs were severely hypoxemic (30 +/- 5 mmHg), hypercapnic (65 +/- 4 mmHg), and acidotic (7.1 +/- 0.05). During the fatigue runs, phrenic stimulation resulted in a marked decrease in Pdi, which amounted at 20 Hz to 70 +/- 8% and 45 +/- 12% of the control values 5 min after the onset of the fatigue runs and at the end, respectively. After recovery (3 h), Pdi and arterial blood gas determinations returned to control values. Identical fatigue runs were repeated with aminophylline infusion (loading dose, 6 mg/kg in 10 min and maintenance dose, 1 mg/kg/h), leading to a plasmatic concentration of 16.4 +/- 2 mg/l. Aminophylline protected the diaphragm against fatigue, and despite the presence of hypoxemia and hypercapnic acidosis, the Pdi generated for a 20 Hz stimulation of the phrenic nerves at identical times of the preceding run amounting to 100 +/- 15% and 85 +/- 10% of control values, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)