Abstract
Purpose::
To evaluate and compare cardiovascular effects (blood pressure and heart rate) of Phenylephrine 2.5% versus Phenylephrine 10%. To compare pupil diameter before and after instilation of eyedrops.
Methods::
This is a prospective, interventional, randomized, comparative study. A total of 58 patients scheduled for fundus examination were dilated with either Phenylephrine 2.5% and Tropicamide 1% (group 0) or Phenylephrine 10% and Tropicamide 1% (group 1). In both groups, blood pressure, heart rate and pupil diameter were measured before and 40 minutes after eyedrops instilation.
Results::
Both groups were similar regarding age and sex, as well as history of hypertension before examination (p=0.07, Kruskal-Wallis test). Mean blood pressure median was 93.3 mmHg in group 0 and 96.6 mmHg in group 1. After eyedrops, values were 93.3 mmHg in group 0 and 96.6 mmHg in group 1, with no significant variation concerning blood pressure (p=0.40). The heart rate median in group 0 was 75 bpm before instilation and 71 bpm after medication; in group 1, values were 77 bpm and 72 bpm respectively. Statistical analysis did not show significant difference between these values (p=0.80). Mean pupil diameter in group 0, before eyedrops, was 3.00 mm, and 2.65 mm in group 1. After medication, mean values were 7.38 mm in group 0 and 7.40 mm in group 1. Variation was 4.38 mm in group 0 and 4.75 mm in group 1, which was statistically significant (p=0.01).
Conclusions::
The combination of Tropicamide 1% with Phenylephrine 10 % provides a better mydriatic effect than Tropicamide 1% with Phenylephrine 2.5%, without significant adverse cardiovascular effects.
Keywords: drug toxicity/drug effects