title: A novel continuous powder aerosolizer (CPA) for inhalative administration of highly concentrated recombinant surfactant protein-C (rSP-C) surfactant to preterm neonates.
abstract: BACKGROUND
  In pulmonary medicine, aerosolization of substances for continuous inhalation is confined to different classes of nebulizers with their inherent limitations. Among the unmet medical needs is the lack of an aerosolized surfactant preparation for inhalation by preterm neonates, to avoid the risks associated with endotracheal intubation and surfactant bolus instillation. In the present report, we describe a high-concentration continuous powder aerosolization system developed for delivery of inhalable surfactant to preterm neonates.
  
  
  METHODS
  The developed device uses a technique that allows efficient aerosolization of dry surfactant powder, generating a surfactant aerosol of high concentration. In a subsequent humidification step, the heated aerosol particles are covered with a surface layer of water. The wet surfactant aerosol is then delivered to the patient interface (e.g., nasal prongs) through a tube.
  
  
  RESULTS
  The performance characteristics of the system are given as mass concentration, dose rate, and size distribution of the generated aerosol. Continuous aerosol flows of about 0.84 L/min can be generated from dry recombinant surfactant protein-C surfactant, with concentrations of up to 12 g/m(3) and median particle sizes of the humidified particles in the range of 3 to 3.5 μm at the patient interface. The system has been successfully used in preclinical studies.
  
  
  CONCLUSIONS
  The device with its continuous high-concentration delivery is promising for noninvasive delivery of surfactant aerosol to neonates and has the potential for becoming a versatile disperser platform closing the gap between continuously operating nebulizers and discontinuously operating dry powder inhaler devices.
authors: 1 Fraunhofer Institute for Toxicology and Experimental Medicine ITEM , D-30625 Hannover, Germany .
authors: G
authors: G
authors: Pohlmann
authors: P
authors: P
authors: Iwatschenko
authors: W
authors: W
authors: Koch
authors: H
authors: H
authors: Windt
authors: M
authors: M
authors: Rast
authors: M Gama
authors: MG
authors: de Abreu
authors: F J H
authors: FJ
authors: Taut
authors: C
authors: C
authors: De Muynck
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols; D002626:Chemistry, Pharmaceutical; D004867:Equipment Design; D006801:Humans; D006813:Humidity; D007231:Infant, Newborn; D007234:Infant, Premature; D008422:Materials Testing; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D011208:Powders; D037721:Pulmonary Surfactant-Associated Protein C / Q000008:administration & dosage* / Q000737:chemistry; D011663:Pulmonary Surfactants / Q000008:administration & dosage* / Q000737:chemistry; D011994:Recombinant Proteins / Q000008:administration & dosage; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy*
chemical_list: D000336:Aerosols; D011208:Powders; D037721:Pulmonary Surfactant-Associated Protein C; D011663:Pulmonary Surfactants; D011994:Recombinant Proteins; C489679:SFTPC protein, human