Prehospital β₂-agonist administration via spacer versus nebuliser

INTRODUCTION. In 2021, administration of β&;-agonist in the ambulance changed from nebuliser to spacer in the North Denmark Region. We aimed to quantify the effectiveness of the switch by comparing 1) dyspnoea score, 2) median pCO2 , pH, and paO2 and 3) vital signs.

METHODS. We conducted a quality assessment study including adults treated in the ambulance with a β&;-agonist from 2018 to 2022 in the North Denmark Region. Prehospital vital signs, dyspnoea scores (0-10) and medicine administration data were collected from the electronic prehospital medical record. Blood gas analyses were collected from the clinical laboratory information system.

RESULTS. A total of 6,521 patient encounters were included, 70% received β&;-agonist by nebuliser and 30% by spacer. Dyspnoea scores were recorded in 45%, arterial blood gas analysis in 62%. The median (interquartile range) last dyspnoea score was 4 (3-6) in both groups, p = 0.79. The nebuliser group had a higher median paCO2 (6.0 versus 5.8, p < 0.001), a lower pH (7.38 versus 7.40, p < 0.001), a higher paO2 (9.20 versus 9.00, p < 0.001), and a higher last measured mean pulse (99 versus 97, p = 0.001) than the spacer group.

CONCLUSIONS. Patients receiving β&;-agonist by spacer had similar relief of dyspnoea as those who received the medicine by nebuliser. Patients using the nebuliser had a higher median paCO2 , a lower pH and a higher pulse rate than patients using the spacer.