TY - JOUR
T1 - Distribution of a second dose of exogenous surfactant in rabbits with severe respiratory failure
AU - Plötz, F. B.
AU - Stevens, H.
AU - Heikamp, A.
AU - Oetomo, S. Bambang
PY - 1995
Y1 - 1995
N2 - Newborn infants with respiratory distress who fail to respond to surfactant treatment receive a second dose of surfactant. The effect of this strategy on the distribution of surfactant to the lung is unknown. We therefore investigated the distribution of the first (fOO mg/kg body weight) and second dose (50 mg/kg body weight) of surfactant (Alveofact) in lung-lavaged rabbits (n = 6). We used141Ce- and103Rn-labeled microspheres that were mixed with the first and second dose of surfactant, respectively. Arterial Po2 increased from 5.7 ± f.f to f0.6 ± 2.0 kPa (p < 0.05) (mean ± SD) after the first and from 20.1 ± 3.8 to 30T ± 2.5 kPa (p < 0.05) after the second dose. Thereafter the rabbits were killed, and the lungs were cut into 200 pieces. The radioactivity of Ce and Rn microspheres was measured and distribution histograms were obtained. Histograms of the first, second, and the total dose of surfactant showed similar nonuniform distribution. Correlation coefficients of the Ce and Rn radioactivity in the different lung lobes widely ranged per lung lobe per rabbit. In addition, the percentage of the number of lung pieces that received an amount of surfactant that was less than the calculated endogenous surfactant pool decreased from 12.5 ± 3.2% to 8.5 ± 3.0% (p < 0.05) after the first and second dose, respectively. This indicates that the second dose was directed both to areas that initially received surfactant and to areas that were still surfactant-deficient. The surfactant-deficient areas were aerated after this second dose, resulting in a further rise in Po2. We conclude that a second dose of surfactant does not lead to homogeneous distribution of surfactant but does result in a significant rise in Po2 that is probably due to increased aeration after the second dose of surfactant, which may be partially related to an additional recruitment of alveoli after the second dose of surfactant. © 1995 International Pediatric Research Foundation, Inc.
AB - Newborn infants with respiratory distress who fail to respond to surfactant treatment receive a second dose of surfactant. The effect of this strategy on the distribution of surfactant to the lung is unknown. We therefore investigated the distribution of the first (fOO mg/kg body weight) and second dose (50 mg/kg body weight) of surfactant (Alveofact) in lung-lavaged rabbits (n = 6). We used141Ce- and103Rn-labeled microspheres that were mixed with the first and second dose of surfactant, respectively. Arterial Po2 increased from 5.7 ± f.f to f0.6 ± 2.0 kPa (p < 0.05) (mean ± SD) after the first and from 20.1 ± 3.8 to 30T ± 2.5 kPa (p < 0.05) after the second dose. Thereafter the rabbits were killed, and the lungs were cut into 200 pieces. The radioactivity of Ce and Rn microspheres was measured and distribution histograms were obtained. Histograms of the first, second, and the total dose of surfactant showed similar nonuniform distribution. Correlation coefficients of the Ce and Rn radioactivity in the different lung lobes widely ranged per lung lobe per rabbit. In addition, the percentage of the number of lung pieces that received an amount of surfactant that was less than the calculated endogenous surfactant pool decreased from 12.5 ± 3.2% to 8.5 ± 3.0% (p < 0.05) after the first and second dose, respectively. This indicates that the second dose was directed both to areas that initially received surfactant and to areas that were still surfactant-deficient. The surfactant-deficient areas were aerated after this second dose, resulting in a further rise in Po2. We conclude that a second dose of surfactant does not lead to homogeneous distribution of surfactant but does result in a significant rise in Po2 that is probably due to increased aeration after the second dose of surfactant, which may be partially related to an additional recruitment of alveoli after the second dose of surfactant. © 1995 International Pediatric Research Foundation, Inc.
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0028914308&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/7596688
U2 - https://doi.org/10.1203/00006450-199504000-00016
DO - https://doi.org/10.1203/00006450-199504000-00016
M3 - Article
C2 - 7596688
SN - 0031-3998
VL - 37
SP - 476
EP - 481
JO - Pediatric Research
JF - Pediatric Research
IS - 4
ER -