Administration Protocol for Isosorbide Dinitrate (Isoket) Drip in Acute Decompensated Heart Failure in ER Setting
For acute decompensated heart failure in the emergency room setting, intravenous isosorbide dinitrate should be administered at an initial dose of 1-10 mg/h, with careful titration based on blood pressure response and symptom relief.1
Patient Selection and Precautions
- Intravenous nitrates are recommended for patients with systolic blood pressure (SBP) >110 mmHg and may be used with caution in patients with SBP between 90-110 mmHg 1
- Contraindicated in patients with SBP <90 mmHg as it may reduce central organ perfusion 1
- Use with extreme caution in patients with aortic stenosis due to risk of marked hypotension 1
- Avoid in patients with right ventricular infarction 1
Administration Protocol
Initial Assessment
- Confirm diagnosis of acute decompensated heart failure 1
- Assess baseline vital signs, especially blood pressure 1
- Evaluate for signs of congestion versus hypoperfusion to guide therapy 1
Preparation and Initial Dosing
- Begin with intravenous isosorbide dinitrate at 1-10 mg/h 1
- For patients with higher blood pressure (>140 mmHg), consider starting at the higher end of the dosing range 1
- Administer via continuous infusion using an infusion pump for precise control 1
Titration Strategy
- Increase dose in increments of 5-10 mg/min every 3-5 minutes as needed 1
- Titrate to achieve symptom relief (reduced dyspnea) and hemodynamic improvement 1
- Target a reduction of approximately 10 mmHg in mean arterial pressure 1
- Monitor blood pressure frequently during titration to avoid precipitous drops 1
Monitoring During Administration
- Continuous monitoring of blood pressure, heart rate, respiratory rate, and oxygen saturation 1
- For patients with borderline blood pressure, consider arterial line placement for more precise monitoring 1
- Assess for symptomatic improvement in dyspnea and signs of congestion 1
- Monitor for headache, which is a common side effect 1
Duration and Maintenance
- Efficacy may diminish after 16-24 hours due to tachyphylaxis 1
- If prolonged therapy is needed, incremental dosing may be required to maintain effect 1
- Consider transitioning to oral nitrates after stabilization 1
Special Considerations
Combination Therapy
- May be combined with loop diuretics (furosemide) for enhanced effect 1
- Titration to the highest hemodynamically tolerable dose of nitrates with low-dose furosemide is superior to high-dose diuretic treatment alone 1
Potential Adverse Effects
- Headache is commonly reported 1
- Risk of hypotension, especially with rapid titration 1
- Tachyphylaxis after 24-48 hours of continuous administration 1
- Methemoglobinemia is rare but possible with high doses 2
Discontinuation
- Reduce dose if SBP falls below 90-100 mmHg 1
- Discontinue permanently if blood pressure drops further or if signs of hypoperfusion develop 1
- Consider transitioning to oral nitrates for longer-term management 1
Clinical Pearls
- Intravenous nitroglycerine (isosorbide dinitrate) is the most widely used vasodilator in AHF with predominantly venodilator effect 1
- Slow titration is key to avoiding large drops in blood pressure 1
- The beneficial effects include decreased preload, afterload, and improved symptoms without compromising stroke volume 1
- For patients with acute coronary syndrome complicating heart failure, nitrates can be particularly beneficial 1, 3