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What is Poractant alfa and explain in detail?
Poractant alfa is a pulmonary surfactant sold under the brand name Curosurf by Chiesi Farmaceutici.  Poractant alfa is an extract of natural porcine lung surfactant. As with other surfactants, marked improvement on oxygenation may occur within minutes of the administration of poractant alfa.
The new generic form of surfactant is Varasurf (Sheep Lung Surfactant) developed in PersisGen Co. and commercialized by ArnaGen Pharmad. It has fully comparable quality profile with Curosurf.

Pharmacology
Each milliliter of poractant alfa contains 80 mg of surfactant (extract) that includes 76 mg of phospholipids and 1 mg of protein of which 0.2 mg is surfactant protein B (SP-B). Depending on local country registration, CUROSURF is available in 1.5 mL vials, 3.0 mL vials, and/or twin packs containing two 1.5 mL vials.The amount of phospholipids is calculated from the content of phosphorus and contains 55 mg of phosphatidylcholine of which 30 mg is dipalmitoylphosphatidylcholine.

Other adverse effects
Transient episodes of bradycardia, decreased oxygen saturation, hypotension, or endotracheal tube blockage may occur.

Mechanism of action
Endogenous pulmonary surfactant reduces surface tension at the air-liquid interface of the alveoli during mechanical ventilation and stabilizes the alveoli against collapse at resting transpulmonary pressures.A deficiency of pulmonary surfactant in preterm infants results in respiratory distress syndrome