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Comparison of the cardiovascular effects of 2.5% phenylephrine and 10% phenylephrine during ophthalmic surgery
R Malhotra1, G Banerjee, W Brampton
1Department of Ophthalmology, Cheltenham General Hospital, UK.
Purpose:
The recommended concentration of topical phenylephrine for mydriasis is still a matter of debate. Our purpose was to compare the cardiovascular effects of 10% and 2.5% topical aqueous phenylephrine.
Methods:
We carried out a double-masked randomised study on 54 consecutive patients undergoing routine local anaesthetic cataract extraction, comparing the effects on blood pressure and heart rate of either 2.5% or 10% topical aqueous phenylephrine in combination with 1% topical aqueous tropicamide in those with no history of cardiovascular disease.
Results:
No difference was found in the rise in blood pressure produced by 2.5% and 10% topical aqueous phenylephrine. We also found no sustained changes in blood pressure or heart rate after instillation of either 2.5% or 10% topical aqueous phenylephrine.
Conclusion:
We recommend the routine use of 2.5% topical aqueous phenylephrine as a mydriatic agent during cataract surgery and acknowledge the role of 10% topical aqueous phenylephrine as an effective mydriatic agent in cases where 2.5% phenylephrine may not be so effective, such as in subjects with darkly pigmented irides.
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