Nicorandil Intravenous Infusion Rate Calculation
For an intravenous nicorandil dose of 5 mg/hr with a concentration of 1 mg/ml, the infusion rate should be set at 5 ml/hr.
Calculation Method
The calculation for determining the infusion rate is straightforward:
Given information:
- Desired dose: 5 mg/hr
- Solution concentration: 1 mg/ml
Formula:
- Infusion rate (ml/hr) = Desired dose (mg/hr) ÷ Concentration (mg/ml)
- Infusion rate = 5 mg/hr ÷ 1 mg/ml = 5 ml/hr
Administration Considerations
When administering intravenous nicorandil, consider the following:
- Ensure the infusion pump is properly calibrated for accurate delivery
- Double-check the calculation with another healthcare provider to prevent medication errors
- Monitor the patient closely for hemodynamic effects, as nicorandil is a potent vasodilator
Hemodynamic Effects and Monitoring
Nicorandil acts as a vasodilator through two mechanisms:
- Potassium channel opening (K-ATP channel activator)
- Nitrate-like action
During administration, monitor for:
- Blood pressure changes - nicorandil can cause significant decreases in both systolic and diastolic pressures 1
- Heart rate - may increase slightly due to vasodilatory effects
- Signs of improved cardiac output - nicorandil has been shown to increase cardiac index by approximately 15.8% 1
Clinical Efficacy
Intravenous nicorandil has demonstrated effectiveness in:
- Decreasing pulmonary artery wedge pressure (PAWP) by about 26.5% 1
- Reducing total peripheral resistance by approximately 13.8% 1
- Improving cardiac index without impairing myocardial contractility 2
Important Considerations
- Nicorandil has a relatively short half-life (approximately 1 hour) 3, 4
- It is rapidly absorbed and distributed with an apparent distribution volume of about 1.4 liters/kg 3
- Unlike some other vasodilators, nicorandil does not appear to cause tolerance with prolonged use 2
Potential Side Effects
- Headache (most common)
- Flushing
- Hypotension
- Monitor for excessive blood pressure reduction, especially in patients already on other antihypertensive medications
Remember to adjust the infusion rate based on the patient's clinical response and hemodynamic parameters.