Calfactant

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Suspension, Intratracheal:

Infasurf: 35 mg phospholipids and 0.7 mg protein per mL (3 mL, 6 mL)

Pharmacology

Mechanism of Action

Endogenous lung surfactant is essential for effective ventilation because it modifies alveolar surface tension, thereby stabilizing the alveoli. Lung surfactant deficiency is the cause of respiratory distress syndrome (RDS) in premature infants and lung surfactant restores surface activity to the lungs of these infants.

Use: Labeled Indications

Respiratory distress syndrome: Prevention of respiratory distress syndrome (RDS) in premature infants <29 weeks gestational age at significant risk; treatment of RDS in neonates ≤72 hours of age with clinical and radiologic confirmation and requiring mechanical ventilation

Contraindications

There are no contraindications listed in the manufacturer's labeling.

Dosage and Administration

Dosing: Pediatric

Respiratory distress syndrome (RDS):

Prophylactic therapy: Premature newborns (<29 weeks gestation): Endotracheal: 3 mL/kg every 12 hours up to a total of 3 doses. In studies, repeat doses have been administered as frequently as every 6 hours for a total of up to 4 doses if the neonate was still intubated and required at least 30% inspired oxygen to maintain arterial oxygen saturations >90% or with a PaO₂ ≤80 torr on >30% inspired oxygen (Bloom 2005; Kattwinkel 2000). However, guidelines suggest that dosing intervals more frequent than every 12 hours should not be necessary, unless surfactant is being inactivated by an infectious process, meconium, or blood (AAP [Polin 2014]).

Rescue treatment: Newborns: Endotracheal: 3 mL/kg every 12 hours up to a total of 3 doses. In studies, repeat doses have been administered as frequently as every 6 hours for a total of up to 4 doses if the neonate was still intubated and required at least 30% inspired oxygen to maintain arterial oxygen saturations >90% or with a PaO₂ ≤80 torr on >30% inspired oxygen (Bloom 2005; Kattwinkel 2000). However, guidelines suggest that dosing intervals more frequent than every 12 hours should not be necessary, unless surfactant is being inactivated by an infectious process, meconium, or blood (AAP [Polin 2014]).

Storage

Gentle swirling or agitation of the vial of suspension is often necessary for redispersion. Do not shake. Visible flecks of the suspension and foaming under the surface are normal. Calfactant should be stored upright (3 mL vial) and under refrigeration at 2°C to 8°C (36°F to 46°F); protect from light; document date and time removed from refrigeration. Warming before administration is not necessary. Unopened and unused vials of calfactant that have been warmed to room temperature can be returned to refrigeration storage within 24 hours for future use. Repeated warming to room temperature should be avoided. Each single-use vial should be entered only once and the vial with any unused material should be discarded after the initial entry.

Drug Interactions

Bradycardia-Causing Agents: May enhance the bradycardic effect of other Bradycardia-Causing Agents. Monitor therapy

Ceritinib: Bradycardia-Causing Agents may enhance the bradycardic effect of Ceritinib. Management: If this combination cannot be avoided, monitor patients for evidence of symptomatic bradycardia, and closely monitor blood pressure and heart rate during therapy. Exceptions are discussed in separate monographs. Consider therapy modification

Fexinidazole [INT]: Bradycardia-Causing Agents may enhance the arrhythmogenic effect of Fexinidazole [INT]. Avoid combination

Ivabradine: Bradycardia-Causing Agents may enhance the bradycardic effect of Ivabradine. Monitor therapy

Lacosamide: Bradycardia-Causing Agents may enhance the AV-blocking effect of Lacosamide. Monitor therapy

Midodrine: May enhance the bradycardic effect of Bradycardia-Causing Agents. Monitor therapy

Ruxolitinib: May enhance the bradycardic effect of Bradycardia-Causing Agents. Management: Ruxolitinib Canadian product labeling recommends avoiding use with bradycardia-causing agents to the extent possible. Monitor therapy

Siponimod: Bradycardia-Causing Agents may enhance the bradycardic effect of Siponimod. Management: Avoid coadministration of siponimod with drugs that may cause bradycardia. Consider therapy modification

Terlipressin: May enhance the bradycardic effect of Bradycardia-Causing Agents. Monitor therapy

Tofacitinib: May enhance the bradycardic effect of Bradycardia-Causing Agents. Monitor therapy

Adverse Reactions

>10%:

Cardiovascular: Bradycardia (34%)

Gastrointestinal: Endotracheal tube reflux (21%)

Respiratory: Cyanosis (65%), airway obstruction (16% to 39%)

Warnings/Precautions

Concerns related to adverse effects:

• Transient adverse effects: Transient episodes of bradycardia, decreased oxygen saturation, endotracheal tube blockage or reflux of calfactant into endotracheal tube may occur. Discontinue dosing procedure and initiate measures to alleviate the condition; may reinstitute after the patient is stable.

Other warnings/precautions:

• Administration: For intratracheal administration only.
• Monitoring: Produces rapid improvements in lung oxygenation and compliance that may require frequent adjustments to oxygen delivery and ventilator settings.
• Trained personnel: Rapidly affects oxygenation and lung compliance; restrict use to a highly-supervised clinical setting with immediate availability of clinicians experienced in intubation and ventilatory management of premature infants.

Monitoring Parameters

Continuous heart rate and transcutaneous O₂ saturation should be monitored during administration; frequent ABG sampling is necessary to prevent postdosing hyperoxia and hypocarbia

Patient Education

• Discuss specific use of drug and side effects with caregiver as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Have caregiver report immediately to prescriber difficulty breathing, blue or gray skin color, or slow heartbeat (HCAHPS).
• Educate caregiver about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Caregiver should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.