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Continuous I.V. infusion: Initial I.V. bolus dose 20-40 mg, followed by continuous I.V. infusion doses of 10-40 mg/hour. If urine output is <1 mL/kg/hour, double as necessary to a maximum of 80-160 mg/hour. The risk associated with higher infusion rates (80-160 mg/hour) must be weighed against alternative strategies. Note: ACC/AHA 2005 guidelines for chronic congestive heart failure recommend 40 mg I.V. load, then 10-40 mg/hour infusion