Abstracts children up to 6 months of life-93 (76.85%). In detail: results in the A and B group were positive in 51 (42.2%) and 42 (34.7%) children respectively. Tests were positive in C group in the amount of 24(19.8%), D group -3(2.5%) and E group -1(0.8%). In the 54 cases (44.6%) of children with the positive result there was a necessity of antibiotic treatment. Conclusion The use of RSV rapid diagnostic test enabled the diagnosis of RSV infection, which especially among the youngest children, had an influence on treatment. Background Severe asthma is treated with bronchodilators like salbutamol, corticosteroids, magnesium sulphate, and if necessary mechanical ventilation. If these options fail, volatile anesthetic agents can be used. This is the first multicentre case series that describes the effectiveness of sevoflurane therapy in children with life-threatening asthma. Methods Pediatric patients admitted to the pediatric intensive care unit (PICU) with severe asthma and sevoflurane treatment were included. A retrospective review of demographic, medical, laboratory and ventilation parameters was performed. Results 7 children from two PICU's in the Netherlands with age ranging from 4 to 13 years were included. The mean length of PICU stay was 6.7 days (range 3-10). Mean (range) dose of sevoflurane and duration of treatment were 2.2% (1-4%) and 24h (0.5-90h). Mean (range) pH at the beginning and at the end of sevoflurane treatment were 7.11 (6.97-7.36) and 7.35 (7.15-7.47)kPa (p<0.01). Mean (range) pCO 2 were respectively 14.3 (5.1-24.8) and 7.1 (4.5-11.4)kPa (p<0.05). Mean (range) peak pressure declined from 33 (23-56) to 22 (14-33) cmH 2 O (p<0.03). Four patients developed hypotension, which was successfully treated with norepinephrine. One patient (dotted line figure), was afterwards judged to suffer from ARDS and indeed failed to respond to sevoflurane therapy. Conclusion Mechanical ventilation with Sevoflurane inhalation is a safe and effective treatment for children with life-threatening asthma.