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Lung Surfactant (Respiratory Distress Syndrome — Neonatal) Pregnancy: Neonatal use only — not applicable to pregnant women.

Poractant Alfa (Porcine Surfactant)

Brand names: Curosurf

Adult dose

Dose: Not applicable — neonatal use only
Route: N/A
Frequency: N/A
Max: N/A
Neonatal respiratory distress syndrome (RDS) only.

Paediatric dose

Dose: Initial rescue dose: 200 mg/kg intratracheal. Subsequent doses: 100 mg/kg every 12 hours if still ventilated (maximum 2 additional doses) mg/kg
Route: Intratracheal (via endotracheal tube or thin catheter INSURE/LISA technique)
Frequency: Initial dose; repeat up to 2 times if required
Max: 400 mg/kg total (initial 200 + up to 2 × 100 mg/kg)
Respiratory distress syndrome (hyaline membrane disease) in premature neonates. Higher initial dose (200 mg/kg) for rescue vs beractant (100 mg/kg) — reason for Curosurf market preference. LISA (Less Invasive Surfactant Administration): thin catheter instillation during CPAP, avoiding intubation — now standard in many UK NICUs for spontaneously breathing infants. Source: BNF for Children 2024; BAPM Guidelines.

Dose adjustments

Renal

No dose adjustment — weight-based only.

Hepatic

No dose adjustment required.

Paediatric weight-based calculator

Respiratory distress syndrome (hyaline membrane disease) in premature neonates. Higher initial dose (200 mg/kg) for rescue vs beractant (100 mg/kg) — reason for Curosurf market preference. LISA (Less Invasive Surfactant Administration): thin catheter instillation during CPAP, avoiding intubation — now standard in many UK NICUs for spontaneously breathing infants. Source: BNF for Children 2024; BAPM Guidelines.

Clinical pearls

  • Mechanism of RDS: surfactant (primarily DPPC and SP-B/SP-C) reduces surface tension at the air-alveolar interface. Premature lungs have insufficient surfactant → progressive alveolar collapse → hypoxic respiratory failure (hyaline membrane disease). Exogenous surfactant replacement reduces surface tension, increases functional residual capacity, and dramatically improves V/Q matching.
  • LISA technique — avoiding intubation: traditional surfactant required endotracheal intubation. LISA (Less Invasive Surfactant Administration) uses a thin catheter inserted into the trachea under direct laryngoscopy while the infant breathes spontaneously on CPAP. Instillation takes 30–60 seconds, catheter removed, CPAP resumed. Meta-analyses show LISA reduces intubation rate, BPD, and IVH vs prophylactic intubation. Becoming standard in most NICUs for infants >28 weeks GA.
  • Poractant alfa vs beractant: poractant alfa (Curosurf) derived from minced pig lungs; contains higher SP-B and SP-C concentration and allows higher initial dose (200 mg/kg). Beractant (Survanta): bovine, 100 mg/kg initial dose. Meta-analyses show poractant alfa reduces supplemental oxygen requirement faster and may reduce mortality — hence Curosurf preference in most UK NICUs.
  • Prophylactic vs rescue: prophylactic surfactant (within 30 min of birth, before respiratory distress develops) in extremely preterm infants — no longer standard practice in many units (LISA/CPAP-first approach reduces overall surfactant exposure). Rescue surfactant (when FiO2 >0.30–0.40 on CPAP) remains the standard. Early intervention is key.
  • Rapid response: improvements in oxygenation typically seen within 5–30 minutes of administration. Reduce FiO2 promptly when SpO2 improves above target (risk of oxygen toxicity and pulmonary haemorrhage from excessive oxygenation post-surfactant). Source: BNF for Children 2024; Polin et al. Pediatrics 2014 (AAP surfactant guidelines); BAPM RDS guidelines.

Contraindications

  • No absolute contraindications for rescue surfactant
  • Relative: unrepaired congenital anomalies incompatible with life — discuss goals of care before administration

Side effects

  • Transient oxygen desaturation during instillation (bradycardia, cyanosis — expected during procedure; resolves with correct technique)
  • Endotracheal tube blockage (thick surfactant — have suction ready; resume ventilation promptly)
  • Pulmonary haemorrhage (rare — associated with rapid improvement in pulmonary mechanics; reduce FiO2 promptly after dosing)
  • Bradycardia, hypotension during instillation (vagal response — ensure stable HR before dose)

Interactions

  • No pharmacological drug interactions — locally acting

Monitoring

  • SpO2 and heart rate continuously during and after administration
  • FiO2 (reduce promptly post-dose — pulmonary haemorrhage risk from excess oxygenation)
  • Blood gas at 30 minutes and 1 hour post-dose (confirm oxygenation improvement)
  • Endotracheal tube patency (resuction if blocked)
  • Repeat chest X-ray at 4–6h post-dose (assess lung field improvement)
  • Clinical assessment for need for repeat dose (FiO2 >0.30–0.40 at 6–12h = consider repeat)

Reference: BNF for Children 2024; BAPM RDS Clinical Practice Guidelines; Polin et al. Pediatrics 2014; Cochrane Review: Seger and Soll 2009 (surfactant types comparison). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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