View - ResearchSpace@Auckland - The University of Auckland

So is induced sputum in adults and children safe? Particularly those with asthma? In 34
asthmatic and normal subjects, a mean fall in FEVr of 5.3Vo was seen, but with a maximum of
20Vo (Pin, Gibson et al. 1992). Pre-treatment with a 9z agonist did not prevent
bronchoconstriction in all the asthmatic subjects, especially in those with a baseline low FEVr
(Wong and Fahy t997). Such pre{reatment in mild asthmatics resulted in an unchanged
FEV1, but with a reduction observed in the normal subjects (Thomas, Yates et al. 1999). One
group also documented that an overuse of F, agonists the day before sputum induction
reduced the protective effect of the pre-medication (Pizzichini, Pizzichini et al. 1997). While
samples were successfully obtained even in subjects with 'difficult to control' asthma, severe
bronchoconstriction occurred in22Vo with development of symptoms and a reduction in FEVr
of > l1%o (ten Brinke, de Lange et al. 2001). Another study noted that the procedure had to be
stopped because of side effects in l2Vo overall and in 17-l8%o of those with severe asthma (de
la Fuente, Romagnoli et al. 1998). When performed as part of their routine clinical visit, the
procedure was well tolerated in over 300 asthmatics, even among those with more severe
respiratory obstruction with an FEVr down to 60Vo predicted or one litre. However in patients
with a baseline FEVr between 4OVo and 59Vo, there was a mean 8Vo reduction in FEVr and in
patients with a baseline FEVr of < 40Vo predicted, 6Vo fellby 2OVo (Vlachos-Mayer, Leigh et
al. 2000). A decrease in arterial oxygen saturations of 6Vo in asthmatic patients, 5.3Vo in
smokers and 67o in healthy subjects has been reported suggesting that patients needed
monitoring during this procedure (Castagnaro, Chetta et al. 1999).
Reviewing the safety in children; in 53 sputum induction alone was tolerated in 98Vo, with
94Vo completing the procedure,92To providing an adequate sample but 4Vo experienced a
>l1vo fall in FEVr (Jones, Hankin et al. 2001). In 182 children who had combined sputum
induction and bronchial provocation testing using hypertonic saline, the procedure was
completed by 90Vo with a distressing cough in l3%o and mucosal irritation with wheeze in IVo
and fewer, 70Vo, successful samples obtained. So while the two investigations can be
combined, this was less well tolerated and resulted in less sampling success (Jones, Hankin et
al. 2001). In 40 children with a baseline FEVr > 65Vo predicted, seven (l8vo) had symptoms
of shortness of breath and wheezing and of these three (8Vo) had a significant fall in FEVr of
greater than 2O7o despite pre-treatment with a bronchodilator (Lex, Payne et al. 2005).In the
CAMP study, nine (87o) of 117 children with mild to moderate asthma developed significant
bronchospasm requiring treatment (Covar, Spahn et aI.2004).
40