A prospective study of atropine premedication in flexible bronchoscopy

This study aimed to assess the effect of atropine premedication prior to flexible bronchoscopy. The rationale for using atropine is that it will dry secretions and allow a better view of the bronchial tree. There is also the theoretical benefit of protection against vasovagal episodes and bronchospasm.

Twenty patients were randomised in a double-blind manner to receive either 500 mcg of atropine intramuscularly or 1 mL of 0.9% saline intramuscularly 30 minutes prior to bronchoscopy. Both groups received a standard dose of intramuscular pethidine. Variables studied included a pre-procedure electrocardiograph, a rhythm strip during the procedure, serial measurements of blood pressure, continuous pulse oximetry, and spirometry pre- and post-bronchoscopy. Subjective measures recorded were a secretion score, rated 0-3 by the bronchoscopist using a four point visual analogue scale. A patient questionnaire was designed to establish the presence or absence of symptoms, including those related to atropine.

There were no significant differences recorded in the duration of procedure, percentage fall in FEV1, secretion scores, or other physiological measures. The only significant difference between the two groups was dry mouth in the atropine group (p<0.001). There was a fall in forced vital capacity from baseline which was significant in the saline group (p<0.005), and not the atropine group, but it was not significant when compared between groups. A beta2 adrenergic agonist would, however, be more appropriate to prevent such a fall in spirometry.

These results fail to demonstrate a benefit of intramuscular atropine as premedication for fibreoptic bronchoscopy.