NIPRIDE RTU- sodium nitroprusside injection, solution
EXELA PHARMA SCIENCES, LLC
(A) EXCESSIVE HYPOTENSION:
Sodium Nitroprusside can cause precipitous decreases in blood pressure which can lead to irreversible ischemic injuries or death. Use only with continuous blood pressure monitoring [see Dosage and Administration (2.2) and Warnings and Precautions (5.1).
(B) CYANIDE TOXICITY:
Sodium nitroprusside metabolism produces dose-related cyanide, which can be lethal. A patient’s ability to buffer cyanide will be exceeded in less than one hour at the maximum dose rate (10 mcg/kg/min); limit infusions at the maximum rate to as short a duration as possible [see Warnings and Precautions (5.2)].
Sodium nitroprusside is indicated for the immediate reduction of blood pressure of adult and pediatric patients in hypertensive crises.
Sodium nitroprusside indicated for induction and maintenance of controlled hypotension in adults and children during surgery, to reduce bleeding.
Sodium nitroprusside is indicated for the treatment of acute heart failure to reduce, left ventricular end-diastolic pressure, pulmonary capillary wedge pressure, peripheral vascular resistance and mean arterial blood pressure.
Inspect parenteral drug products for particulate matter and discoloration prior to administration, whenever solution and container permit. Sodium nitroprusside should be a clear colorless to red/brown color; do not use if solution is blue, green, or bright red.
Continuously monitor blood pressure in patients receiving sodium nitroprusside. Start infusion of sodium nitroprusside at a rate of 0.3 mcg/kg/min. Evaluate blood pressure for at least 5 minutes before titrating to a higher or lower dose to achieve the desired blood pressure. The dose may be titrated upward until:
- the desired effect is achieved,
- systemic blood pressure cannot be further reduced without compromising the perfusion of vital organs, or
- the maximum recommended infusion rate of 10 mcg/kg/min has been reached, whichever occurs first.
In patients with eGFR <30 mL/min/1.73 m2 , limit the mean infusion rate to less than 3 mcg/kg/min. In anuric patients, limit the mean infusion rate to 1 mcg/kg/min.
Do not administer other drugs in the same solution with sodium nitroprusside.
Sodium nitroprusside must be delivered by a volumetric infusion pump because small variations in infusion rate can lead to wide, undesirable variations in blood pressure [see Clinical Pharmacology (12.2)].
Injection: 50 mg/100 mL of 0.9% sodium chloride (0.5 mg/mL), 20 mg/100 mL of 0.9% sodium chloride (0.2 mg/mL), and 10 mg/50 mL of 0.9% sodium chloride (0.2 mg/mL). NIPRIDE ® RTU is supplied as a sterile, unpreserved, colorless to red-brown solution available in a single-use vial.
- Diseases with compensatory hypertension (e.g., coarctation of the aorta, arteriovenous shunting).
- Inadequate cerebral circulation or in moribund patients (A.S.A. Class 5E) coming to emergency surgery.
- Patients with congenital (Leber’s) optic atrophy or with tobacco amblyopia.
- Acute heart failure associated with reduced peripheral vascular resistance.
- Concomitant use with sildenafil, tadalafil, vardenifil, or riociguat.
Sodium nitroprusside, can cause excessive hypotension leading to hypoperfusion of vital organs. Hypotension should resolve within 1-10 minutes after discontinuation of the nitroprusside infusion; during these few minutes, it may be helpful to put the patient into a head-down (Trendelenburg) position to maximize venous return. If hypotension persists more than a few minutes after discontinuation, consider other causes. Elderly patients may be more sensitive to the hypotensive effects of the drug.
Sodium nitroprusside infusions above 2 mcg/kg/min generate cyanide ion (CN¯) faster than the body can normally dispose of it. At the maximum recommended infusion rate of 10 mcg/kg/min, the patient’s ability to buffer CN¯ will be exceeded in less than one hour [see Overdose (10)].
Patients with hepatic dysfunction are more susceptible to cyanide toxicity.
An early manifestation of cyanide toxicity is increasing dosage requirements to maintain blood pressure control. Metabolic acidosis may not be evident for more than an hour after toxic cyanide levels accumulate.
If cyanide toxicity develops, discontinue sodium nitroprusside, and consider specific treatment of cyanide toxicity [see Overdosage (10)].
Most of the cyanide produced during metabolism of sodium nitroprusside is eliminated in the form of thiocyanate. Thiocyanate is mildly neurotoxic (tinnitus, miosis, hyperreflexia) at serum levels of 1 mmol/L (60 mg/L). Thiocyanate is life-threatening when levels reach ~200 mg/L. Therefore, routine monitoring of plasma thiocyanate levels is recommended in patients with normal renal function when cumulative sodium nitroprusside doses exceed 7 mg/kg/day. In patients with eGFR <30 mL/min/1.73 m2, limit the mean infusion rate to less than 3 mcg/kg/min. In anuric patients, limit the mean infusion rate to 1 mcg/kg/min.
Renal hemodialysis may be used to eliminate thiocyanate in cases of severe toxicity.
Sodium nitroprusside infusions cause conversion of hemoglobin to methemoglobin in a dose-dependent manner. Methemoglobin binds oxygen more strongly than does hemoglobin, and when methemoglobin levels are elevated, oxygen release from red blood cells in tissue capillaries may be impaired. However, conversion of methemoglobin back to hemoglobin is normally rapid, and clinically significant methemoglobinemia is infrequent.
Suspect methemoglobinemia in patients who have received >10 mg/kg of sodium nitroprusside and who exhibit signs of impaired oxygen delivery despite adequate cardiac output and adequate arterial pO2. Methemoglobinemic blood is chocolate brown, without the expected color change on exposure to air. Methemoglobin levels >10% are considered clinically significant.
When methemoglobinemia is diagnosed, the treatment of choice is 1-2 mg/kg of methylene blue, administered intravenously over several minutes.
Like other vasodilators, sodium nitroprusside can cause increases in intracranial pressure.
When sodium nitroprusside (or any other vasodilator) is used for controlled hypotension during anesthesia, the patient’s capacity to compensate for anemia and hypovolemia may be diminished. If possible, correct pre-existing anemia and hypovolemia prior to administration.
The following adverse reactions are described, or described in greater detail, in other sections:
- Hypotension [see Warnings and Precautions (5.1)]
- Cyanide Toxicity [see Warnings and Precautions (5.2)]
- Thiocyanate Toxicity [see Warnings and Precautions (5.3)]
- Methemoglobinemia [see Warnings and Precautions (5.4)]
- Increased Intracranial Pressure [see Warnings and Precautions (5.5)]
- Anemia and Hypovolemia [see Warnings and Precautions (5.6)]
Less common adverse reactions include:
Cardiovascular: Bradycardia, electrocardiographic changes, tachycardia, palpitations, retrosternal discomfort
Gastrointestinal: Ileus, nausea, abdominal pain
Hematologic: Decreased platelet aggregation
Musculoskelatal: Muscle twitching
Neurologic: Increased intracranial pressure, dizziness, headache
Miscellaneous: Flushing, diaphoresis, venous streaking, irritation at the infusion site
All MedLibrary.org resources are included in as near-original form as possible, meaning that the information from the original provider has been rendered here with only typographical or stylistic modifications and not with any substantive alterations of content, meaning or intent.