It takes only slightly longer to deliver an inhaled therapy in cystic fibrosis (CF) patients sitting upright than when lying alternately on either side, according to an Australian study.
Usually, doctors have patients sit upright when inhaling nebulized medications in order to maximize the lung’s volume. However, experts say distribution patterns of nebulized therapies in the lungs are not uniform in CF patients, with the lungs’ upper lobes receiving lower doses of therapy.
The study, “The use of an alternate side lying positioning strategy during inhalation therapy does not prolong nebulization time in adults with Cystic Fibrosis: a randomised crossover trial,” appeared in the journal BMC Pulmonary Medicine.
The trial (ACTRN12611000672954) of 24 adults with CF measured the time taken to deliver nebulized saline using the LC Star nebulizer. Researchers at Australia’s University of Sydney wanted to know whether having inhalation therapy when lying down —alternating between the left and right sides — would affect the time taken to deliver a fixed amount of saline, compared to delivery time when sitting upright.
They found that the delivery time for 4 mL of saline (salt solution) averaged 18.54 minutes for patients sitting upright, and 17.96 minutes for those doing alternate side lying.
Researchers calculated that changing sides up to every two minutes resulted in even amounts of saline delivered to both lungs. They predicted that changing sides every three minutes would cause an imbalance in the amounts of saline delivered to each lung.
“This study will be useful to inform the design of further studies about the effects of body position on nebulized drug delivery. Subsequent future work could then consider the impact of body position in relation to faster delivery systems and other inhaled therapies (dornase alfa, antibiotics) with differing viscosities,” researchers wrote.
They also emphasized that before recommending alternate side lying in inhalation therapy, further studies are needed to establish the actual distribution patterns of inhaled therapies in the lungs.
“The use of an alternate side lying positioning strategy during nebulized therapies does appear to be suitable, from the perspective of nebulizer delivery time, as an alternative to upright sitting,” the team said. “However, while total nebulizer dosage delivered while in each side lying position does appear to be equitable if the side is changed at least every two months, further investigation of the side lying regimen’s specific effect on the pattern of drug deposition is needed before this position can be recommended.”