title: Aerosol delivery in ventilated newborn pigs: an MRI evaluation.
abstract: Pulmonary deposition of inhaled drugs in ventilated neonates has not been studied in vivo. The objective of this study was to evaluate pulmonary delivery of gadopentetate dimeglumine (Gd-DTPA) following nebulization in ventilated piglets using magnetic resonance imaging. Seven ventilated piglets (5 +/- 2 d old, weight 1.8 +/- 0.5 kg) were scanned in the Bruker/Siemens 4T magnetic resonance scanner using T1 weighted spin-echo sequence. Aerosols of Gd-DTPA were generated continuously using the MiniHeart jet nebulizer. Breath-hold coronal images were obtained before and every 10 min during aerosolized Gd-DTPA for 90 min. Signal intensity (SI) changes over the lungs, kidneys, liver, skeletal muscle, and heart were evaluated. A significant increase in SI was observed in the lungs, kidney, and liver at 10, 20, and 40 min respectively after start of aerosol. At the end of 90 min, the SI increased by 95%, 101%, and 426% over the right lung, left lung, and kidney, respectively. A much smaller increase in SI was observed over the liver. In conclusion, we have demonstrated effective pulmonary aerosol delivery within 10 min of contrast nebulization in ventilated piglets. Contrast visualization in the kidneys within 20 min of aerosol initiation reflects alveolar absorption, glomerular filtration and renal concentration.
authors.affiliation: Department of Pediatrics, Children's Hospital of Michigan, 4H42, Detroit, MI 48201, USA. bsood@med.wayne.edu
authors.forename: Beena G
authors.initials: BG
authors.lastname: Sood
authors.forename: Yimin
authors.initials: Y
authors.lastname: Shen
authors.forename: Zahid
authors.initials: Z
authors.lastname: Latif
authors.forename: Xinguang
authors.initials: X
authors.lastname: Chen
authors.forename: Jody
authors.initials: J
authors.lastname: Sharp
authors.forename: Jaladhar
authors.initials: J
authors.lastname: Neelavalli
authors.forename: Aparna
authors.initials: A
authors.lastname: Joshi
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Slovis
authors.forename: E M
authors.initials: EM
authors.lastname: Haacke
mesh_terms: D000042:Absorption / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000295:instrumentation* / Q000379:methods; D019786:Gadolinium DTPA / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005919:Glomerular Filtration Rate / Q000502:physiology; D007668:Kidney / Q000033:anatomy & histology / Q000378:metabolism; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism; D008168:Lung / Q000033:anatomy & histology / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism; D009330:Nebulizers and Vaporizers; D013552:Swine; D012122:Ventilators, Mechanical
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA