management of acute severe asthma in a pediatric intensive care unit

The hospitalization and mortality rates incurred from acute childhood asthma continue to rise in the past decade. The purpose of this study is to examine the outcome, morbidity and the management of children admitted with acute asthma to our pediatric intensive care unit [PICU] and compare it with those described in the literature. Medical records of all children admitted with acute severe asthma to PICU at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia over an 8-year period [1994-2001] were reviewed. Fifty-six patients were analyzed. The male to female ratio was 1.3:1 and the mean age was 3.6 +/- 2.8 years. The mean duration of symptoms prior to admission was 2 +/- 1.5 days with 39.3% <24 hours. A positive family history of allergy was present in two third of patients. The average stay in PICU was 2 +/- 0.9 days. Seventy-three% of patients received prophylaxis bronchodilator therapy before hospital admission including inhaled steroid in 62%. All the patients received nebulized salbutamol and intravenous corticosteroid. Two third of our patients received nebulized ipratropium bromide and 62% intravenous aminophylline. From arterial blood gases analysis, 46.4% had hypercapnia [PaCO2 >45 mm Hg]. None of our patients required mechanical ventilation. Only 2 patients developed pneumomediastinum with pneumothorax that has resolved spontaneously without intervention. There were no deaths among our 56 patients admitted to PICU. We conclude that the mortality and morbidity in children with severe asthma, who require PICU admissions are minimal, provided optimal early use of bronchodilators and intravenous steroids. Using this approach, it could also be possible to avoid mechanical ventilation and shorten the duration of hospital admission

House dust mite allergens in Saudi Arabia: regional variations and immune response

In order to assess the causative extrinsic allergic factors[s] in school-age children diagnosed as having bronchial asthma and allergic rhinitis, and to qualitatively and quantitatively evaluate the presence of house dust mites [HDM[s]] in the homes of these children in Saudi Arabia, a study analyzing mite contents in 165 samples collected from patients' indoor environment was conducted. The dust samples were collected from four regions of Saudi Arabia, showing variation in their geography and climate. Immunochemical assays were performed using ALK regents by ELISA technique. A total of 462 children were also tested using skin prick test [SPT] method for I[g]E-mediated reactions to HDM[s]. The samples from the Central dry region revealed a very low amount of the potent house dust mites [Dermatophagiodes pteronyssinus and D. farina, the two dominant species in various parts of the world]. The sample from the Southern mountains region contacted a very high concentration of Der p I [84, 000 ng/g of dust], while the Western coastal region showed a high concentration of Der f I [up to 22, 000 ng/g]. The mid-Western agricultural region did not exhibit any significant level of either Der p I or Der f I. The maximum level of D. pteronyssinus detected in the Central dry region was 106 ng/g of dust. The data exhibit both qualitative and quantitative variations of HDM[s] in the three regions and may be attributed to variation in geography and climate, particularly humidity of the regions, which vary significantly. Riyadh in the Central region is considered to have low humidity [<40%], while humidity in the Western coastal region, Jeddah, and the Southern region of Abha is comparatively higher, which helps house dust mites thrive. SPT result in these regions with house dust mite allergens [in addition to other common inhalant allergens] also revealed a considerable number of I[g]E-mediated reactions, consistent with the frequency of house dust mites in the region. Though more data are being accumulated on the subject to conduct a statistical comparison and more skin tests are underway in the Southern region, the study suggests the presence of at least two HDM[s] as well as qualitative diversity and quantitative variation of house dust mites in Saudi Arabia. The study also indicates, with a considerable number of I[g]E-mediated reactions, the possible influence of mites in the allergic manifestations of many patients, which is not only common, but increasing in parts of the county