Background: Methods of converting treatment with i.v. nitroglycerin to treatment with nitroglycerin ointment 2% vary greatly and may affect the length of time patients remain in the ICU, nursing time, and possible recurrent angina. To date, no randomized, controlled studies have evaluated the methods used for conversion.
Objective: To evaluate two methods of conversion.
Methods: Two hundred patients receiving i.v. nitroglycerin at doses of 10 to 100 micrograms/min were randomized to two methods of conversion: (1) Apply nitroglycerin ointment and stop i.v. nitroglycerin 30 minutes later. (2) Decrease the dose of i.v. nitroglycerin by 10 micrograms/min every 15 minutes, apply one half the dose of nitroglycerin ointment when the original i.v. dose has been decreased by one half, and apply the full dose of the ointment when the i.v. nitroglycerin is stopped. The primary end point was the time patients remained in the ICU after the conversion. Secondary end points included time to hospital discharge, estimate of nursing time, and selected clinical end points. Kaplan-Meier and Cox regression analyses were used to evaluate time patients remained in the ICU and nursing time. Clinical outcomes were analyzed by using a chi-square test.
Results: Use of the first method reduced median time before transfer from the ICU by 23 minutes and median nursing time by 45 minutes. Analysis of all clinical outcomes showed no differences between the two methods.
Conclusions: Use of the first method was associated with a reduction in the time patients remained in the ICU before transfer to another unit and savings in nursing time, but the two methods did not differ according to clinical outcomes.