What is the initial infusion rate in cc/hr of Isoket (Isosorbide dinitrate) for a patient?

Initial Infusion Rate of Isosorbide Dinitrate (Isoket)

The initial recommended infusion rate for Isosorbide dinitrate (Isoket) is 10-20 mcg/min (or 0.6-1.2 mg/hour), which should be titrated up in increments of 5-10 mcg/min every 3-5 minutes as needed based on clinical response. 1

Dosing Guidelines

• Intravenous isosorbide dinitrate is indicated for patients with acute heart failure with systolic blood pressure >110 mmHg and may be used with caution in patients with SBP between 90-110 mmHg 1
• The initial infusion should start at 10-20 mcg/min, which translates to approximately 0.6-1.2 mg/hour 1
• Titration should occur in increments of 5-10 mcg/min every 3-5 minutes based on symptom relief or blood pressure response 1
• If no response is seen at 20 mcg/min, increments of 10 and later 20 mcg/min can be used 1
• The maximum dose is typically 200 mcg/min, though this ceiling is based on common practice rather than formal recommendations 1

Administration Considerations

• Administer through continuous infusion via non-absorbing tubing 1
• Slow titration with frequent blood pressure monitoring is essential to avoid large drops in systolic blood pressure 1
• An arterial line is not routinely required but will facilitate titration in patients with borderline pressures 1
• If symptoms and signs of ischemia are relieved, there is no need to continue increasing the dose to effect a blood pressure response 1

Monitoring and Precautions

• Systolic blood pressure generally should not be titrated to less than 110 mmHg in previously normotensive patients or to greater than 25% below the starting mean arterial blood pressure if hypertension was present 1
• Avoid use in patients with initial systolic blood pressure less than 90 mmHg, as it may reduce central organ perfusion 1
• Hypotension should be avoided, especially in patients with renal dysfunction 1
• Patients with aortic stenosis may demonstrate marked hypotension following initiation of IV vasodilator treatment 1
• Monitor for headache, which is frequently reported with nitrates 1
• Be aware that tachyphylaxis is common after 24-48 hours, necessitating incremental dosing 1

Converting to Other Nitrate Formulations

• When patients have been free of ischemic discomfort for 12-24 hours, attempt to reduce the dose of IV isosorbide dinitrate and switch to oral or topical nitrates 1
• For sustained therapy, consider oral isosorbide dinitrate at 5-80 mg, 2 or 3 times daily, or slow-release formulations at 40 mg 1-2 times daily 1

Special Considerations

• Contraindicated after the use of phosphodiesterase inhibitors: sildenafil within 24 hours, tadalafil within 48 hours due to risk of profound hypotension 1
• Use with extreme caution in patients with inferior wall MI with right ventricular involvement, as these patients are preload dependent and may experience profound hypotension 1
• In patients with acute coronary syndrome, monitor closely as abrupt hypotension can occur 1