OPTISON (perflutren protein-type A microspheres)
Optison (perflutren protein-type A microspheres) injectable suspension is an ultrasound contrast agent for intravenous injection. The vial contains a clear liquid lower layer, a white liquid upper layer, and a headspace filled with perflutren gas. After resuspension, the sterile suspension is homogeneous, opaque, and milky-white.
Perflutren is chemically characterized as 1,1,1,2,2,3,3,3-perflutren with a molecular weight of 188, an empirical formula of C3F8
Each mL of Optison contains 5.0-8.0×108 protein-type A microspheres, 10 mg albumin human, 0.22 ± 0.11 mg/mL perflutren; and the following excipients: 0.2 mg N-acetyltryptophan, and 0.12 mg caprylic acid in 0.9% aqueous sodium chloride. The headspace of the vial is filled with perflutren gas. The pH is adjusted to 6.4-7.4. The protein in the microsphere shell makes up approximately 5-7% (w/w) of the total protein in the suspension.
Indications and usage
Optison is an ultrasound contrast agent indicated for use in patients with suboptimal echocardiograms to opacify the left ventricle and to improve the delineation of the left ventricular endocardial borders.
Mechanism of Action
The Optison microspheres create an echogenic contrast effect in the blood. The acoustic impedance of the Optison microspheres is much lower than that of the blood. Therefore, impinging ultrasound waves are scattered and reflected at the microsphere-blood interface and ultimately may be visualized in the ultrasound image. At the frequencies used in adult echocardiography (2-5 MHz), the microspheres resonate which further increases the extent of ultrasound scattering and reflection.
Dosage and administration
- Recommended dose of Optison is 0.5 mL injected into a peripheral vein
- Maximum total dose should not exceed 5.0 mL in any 10 minute period
- Maximum total dose should not exceed 8.7 mL in any one patient study
- If contrast enhancement is inadequate after the dose of 0.5 mL, additional doses of increments of 0.5 mL up to 5.0 mL in a 10 minutes period may be injected intravenously up to a maximum total dose of 8.7 mL.
- Inspect visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Do not inject if the solution is not opaque, milky-white, and absent particulate matter.
- Inject through a 20-gauge or larger angiocatheter into a peripheral vein at a rate not exceeding 1 mL per second. Suggested methods of administration include: a short extension tubing, heparin lock, or intravenous line, all with a 3-way stopcock.
- Administer intravenously; do not administer Optison by intra-arterial injection
- Do not aspirate blood back into the Optison containing syringe before administration; this may promote the formation of a blood clot within the syringe.
- For short extension tubing or heparin lock: fill one syringe with 0.9% Sodium Chloride Injection, USP, and FLUSH the line for patency before and after the injection of Optison.
- For a continuous intravenous line: open an intravenous line with 0.9% Sodium Chloride Injection, USP (or 5% Dextrose Injection, USP) at a slow infusion rate to maintain vascular patency. Flush the line immediately after injection of Optison
- Do not use the single-patient use vial for more than one patient. Discard unused product.
Do not administer Optison to patients with known or suspected hypersensitivity to perflutren, blood, blood products or albumin
Warnings and precautions
Serious Cardiopulmonary Reactions: Serious cardiopulmonary reactions including fatalities have occurred uncommonly during or shortly following perflutren-containing microsphere administration, typically within 30 minutes of administration. The risk for these reactions may be increased among patients with unstable cardiopulmonary conditions (acute myocardial infarction, acute coronary artery syndromes, worsening or unstable congestive heart failure, or serious ventricular arrhythmias).
The reported reactions to perflutren-containing microspheres include: fatal cardiac or respiratory arrest, shock, syncope, symptomatic arrhythmias (atrial fibrillation, tachycardia, bradycardia, supraventricular tachycardia, ventricular fibrillation, ventricular tachycardia), hypertension, hypotension, dyspnea, hypoxia, chest pain, respiratory distress, stridor, wheezing, loss of consciousness and convulsions
Always have cardiopulmonary resuscitation personnel and equipment readily available prior to Optison administration and monitor all patients for acute reactions.
Hypersensitivity Reactions: Serious anaphylactic reactions have been observed during or shortly following perflutrencontaining microsphere administration including: Shock, hypersensitivity, bronchospasm, throat tightness, angioedema, edema (pharyngeal, palatal, mouth, peripheral, localized), swelling (face, eye, lip, tongue upper airway), facial hypoesthesia, rash, urticaria, pruritus, flushing, and erythema have occurred in patients with no prior exposure to perflutren-containing microsphere products. Always have cardiopulmonary resuscitation personnel and equipment readily available prior to Optison administration and monitor all patients for hypersensitivity reactions.
Systemic Embolization: When administering Optison to patients with a cardiac shunt, microspheres can bypass filtering of the lung and enter the arterial circulation. Assess patients with shunts for embolic phenomena following Optison administration. Optison is only for intravenous administration; do not administer Optison by intra-arterial injection
Ventricular Arrhythmia Related to High Mechanical Index: High ultrasound mechanical index values may cause microsphere rupture and lead to ventricular arrhythmias. Additionally, end-systolic triggering with high mechanical indices has been reported to cause ventricular arrhythmias. Optison is not recommended for use at mechanical indices greater than 0.8.
Transmissible Infectious Agents: This product contains albumin, a derivative of human blood. Based on effective donor screening and product manufacturing processes, it carries an extremely remote risk for transmission of viral disease. A theoretical risk for transmission of Creutzfeldt-Jakob disease (CJD) also is considered extremely remote. No cases of transmission of viral disease or CJD have ever been identified for albumin.
Most common adverse reactions during treatment: headache, nausea and/or vomiting, warm sensation or flushing, and dizziness
Use in specific populations
Pregnancy: There are no data with Optison use in pregnant women to inform any drug-associated risks. No adverse developmental outcomes were observed in animal reproduction studies with intravenous administration of Optison to pregnant rats and rabbits during organogenesis at doses up to at least 5 and 10 times the recommended human dose based on body surface area
Lactation: There are no data on the presence of perflutren protein-type A microspheres in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Optison and any potential adverse effects on the breastfed infant from Optison or from the underlying maternal condition.
Pediatric Use: Safety and effectiveness in pediatric patients have not been established.
Geriatric Use: Of the total number of subjects in a clinical study of Optison, 35% were 65 and over, while 14 % were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.