Myopathy complicating the therapy of severe asthma has been recently described in several case reports. Twenty-five consecutive patients admitted to the intensive care unit (ICU) at this hospital for mechanical ventilation for severe asthma were studied for the incidence of creatine kinase (CK) enzyme rise and for the development of clinical myopathy. Pharmacologic therapy was standardized, every patient receiving corticosteroids and aminophylline intravenously and salbutamol both nebulized and intravenously. Twenty-two patients received muscle relaxant therapy with vecuronium. In 19 of 25 (76%) of patients there was elevation of CK levels to a median of 1,575 U/L (range, 66 to 7,430) occurring 3.6 +/- 1.5 days after admission. In nine patients there was clinically detectable myopathy. The presence of either myopathy or CK enzyme rise was associated with a significant prolongation of ventilation time. Arterial blood gas measurements on admission to the ICU revealed a pH (mean +/- SD) of 7.07 +/- 0.21, a PaCO2 of 87.2 +/- 32.7, and a PaO2 (with a high FIO2) of 129 +/- 97 mm Hg; however, no correlation was found between the severity of initial metabolic disturbance and the subsequent development of myopathy. There was no association between the type of corticosteroid administered and the subsequent development of myopathy. Patients with myopathy had received a significantly higher total dose of vecuronium when compared with those who did not develop myopathy (p < 0.001, Kruskal Wallis test). We have therefore found a surprisingly high incidence of CK enzyme rise and myopathy in this group of mechanically ventilated patients with severe asthma.(ABSTRACT TRUNCATED AT 250 WORDS)

Objectives To compare the prevalence of asthma, hay fever and atopy in Asian immigrants in Melbourne with that in Australian‐born non‐Asians and Australian‐born Asians, and to investigate the association of these conditions with atopic status, length of stay in Australia and IgE levels in Asian immigrants. Design We performed a cross‐sectional study by telephone interviews, using standard questionnaire items on respiratory and allergic symptoms. A random sample of 636 recent Asian immigrants of ethnic Chinese origin, 109 Australian‐born Asians and 424 Aus‐tralian‐born non‐Asians were selected from the 1991 Melbourne Telephone Directory, using a presumptive surname list. Skin tests to determine atopic status were performed on 269 Asian immigrants and 167 of these also had serum levels of total and specific IgE estimated. Results In the under 20 years age group the prevalence of wheeze or asthma ever was higher in Aus‐tralian‐born non‐Asians and Aus‐tralian‐born Asians than in Asian immigrants (P< 0.001), and the prevalence of hay fever was higher in Asian immigrants and Aus‐tralian‐born Asians than in Australian‐born non‐Asians. In those older than 20 years, hay fever was almost twice as common in Asian immigrants as in Australian‐born non‐Asians (P< 0.001 for 20‐40 years age group; P<0.01 for >40 years). The prevalence of hay fever and, to a lesser degree, asthma in Asian immigrants increased significantly with length of stay in Australia, independent of age at arrival, sex and atopic status (trend test: P< 0.001 for hay fever; />=0.05 for asthma). Atopy was more common in Asian immigrants and Australian‐born Asians than in Australian‐born non‐Asians (P< 0.001) and was very strongly associated with both hay fever and asthma, irrespective of length of stay. Pollen and mite sensitivities were more common in Asian subjects (twice as common for Asian‐born and 1.5 times for Australian‐born) than non‐Asian subjects (P<0.01). Among Asian immigrants, elevated total IgE level (>100IU/mL) was strongly associated with a history of hay fever (P< 0.01) and wheeze or asthma ever (P<0.05), atopy (P< 0.001) and the presence of specific IgE antibodies to grass pollen, dust mite, cockroach and Ascaris antigens (P<0.05 for all). Conclusion We found substantial differences in the prevalence of asthma, hay fever and atopy between Asian immigrants, Australian‐born Asians and non‐Asians. The prevalence of hay fever and asthma in Asian immigrants was strongly associated with length of stay in Australia, suggesting that environmental factors are important in the pathogenesis of these diseases.

Acute severe asthma is associated with significant morbidity and mortality. We retrospectively quantified hypotension, pulmonary barotrauma, and cardiac arrhythmias in all patients with severe asthma admitted to the intensive care unit (ICU) and prospectively evaluated the predictive value of a measurement of dynamic hyperinflation (DHI) in those patients who required mechanical ventilation. In the first study, 88 ICU admissions for severe asthma over 5 yr (73 patients, 40 +/- 18 yr, 36 men, 37 women) were evaluated. Fifty-one admissions were mechanically ventilated, 29 were not, and 8 previously ventilated patients remained briefly intubated but were not ventilated in the ICU. Hypotension (18/88, 20%), pulmonary barotrauma (12/88, 14%), and arrhythmias (9/88, 10%) were entirely confined to patients who had been mechanically ventilated. There were no significant differences in ventilatory parameters, airway pressures, or blood gases between mechanically ventilated patients with and without complications. Two patients with previous severe hypoxic cerebral damage died from this complication after ICU discharge. In the second study, the end-inspiratory lung volume (VEI) (1) was compared with standard ventilatory parameters in 22 patients. There were no ICU deaths, but high incidences of pulmonary barotrauma (27%) and hypotension (41%) were found. Both minute ventilation (VE and VEI) were significantly higher in patients who developed complications (VE 13.7 +/- 3.0 versus 11.2 +/- 2.5 L/min, VEI 26.1 +/- 4.7 versus 20.0 +/- 7.4 ml/kg, p less than 0.05) but only VEI had a threshold value significantly predictive of complications. For VEI less than 1.4 L, 0/5 (0%) patients had complications; for VEI greater than or equal to 1.4 L, 11/17 (65%) had complications (p = 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Symptoms of asthma and anaphylaxis seen in subjects following ingestion of royal jelly were true IgE-mediated hypersensitivity reactions. The clinical significance of the antibodies found in the sera of control subjects is not known but they may arise in response to common inhalant allergens that show allergenic cross-reactivity with royal jelly.

Mechanical ventilation causes significant morbidity and mortality in patients with severe asthma. Hypoventilation may reduce this morbidity and mortality, but indicators to guide the degree of hypoventilation are unclear. We used a measure of pulmonary hyperinflation to assess the degree of airflow obstruction and to guide the extent and duration of hypoventilation. Ten patients who required mechanical ventilation for acute severe asthma were studied. All were sedated, paralyzed, and given an initial minute ventilation (VE) of 200 ml/kg/min. End-inspiratory lung volume (VEI) above FRC was measured from the total exhaled gas volume during 40 to 60 s of apnea. VEI was used to regulate VE to a safe level (VEsafe), irrespective of PaCO2, by reducing the rate when VEI was > 20 ml/kg and increasing it when VEI was < 20 ml/kg. Each patient was weaned when VEsafe resulted in PaCO2 < or = 40 mm Hg (the weaning point). FRC was measured computer analysis of anterior and lateral chest radiographs taken at the end of apnea. Using the weaning point criterion, 2 patients (PaCO2 < 40 mm Hg) were weaned shortly after arrival. The remaining eight (initial PaCO2, 63 +/- 17 mm Hg) continued hypoventilation until the weaning point was reached (30 +/- 29 h). The weaning point was reached by the VE required for PaCO2 40 mm Hg decreasing concurrent with the VEsafe increasing. All but 1 patient were successfully weaned within 24 h of the weaning point.(ABSTRACT TRUNCATED AT 250 WORDS)