Different doses of exogenous surfactant for treatment of meconium aspiration syndrome in newborn rabbits

Authors

  • João Cesar Lyra University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Renata S. Mascaretti University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Alexander Roberto Precioso University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Yin Chia Chang University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Maria Tereza Zulini da Costa University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Flávio Adolfo Costa Vaz University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Yassuhiko Okay University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas
  • Celso Moura Rebello University of São Paulo and University Hospital; Faculty of Medicine; Hospital das Clínicas

DOI:

https://doi.org/10.1590/S0041-87812004000300003

Keywords:

Meconium, Surfactant inactivation, Neonate, Newborn animals, Pulmonary mechanics

Abstract

OBJECTIVE: To evaluate the effects of 2 different doses of exogenous surfactant on pulmonary mechanics and on the regularity of pulmonary parenchyma inflation in newborn rabbits. METHOD: Newborn rabbits were submitted to tracheostomy and randomized into 4 study groups: the Control group did not receive any material inside the trachea; the MEC group was instilled with meconium, without surfactant treatment; the S100 and S200 groups were instilled with meconium and were treated with 100 and 200 mg/kg of exogenous surfactant (produced by Instituto Butantan) respectively. Animals from the 4 groups were mechanically ventilated during a 25-minute period. Dynamic compliance, ventilatory pressure, tidal volume, and maximum lung volume (P-V curve) were evaluated. Histological analysis was conducted using the mean linear intercept (Lm), and the lung tissue distortion index (SDI) was derived from the standard deviation of the means of the Lm. One-way analysis of variance was used with a = 0.05. RESULTS: After 25 minutes of ventilation, dynamic compliance (mL/cm H2O · kg) was 0.87 ± 0.07 (Control); 0.49 ± 0.04 (MEC*); 0.67 ± 0.06 (S100); and 0.67 ± 0.08 (S200), and ventilatory pressure (cm H2O) was 9.0 ± 0.9 (Control); 16.5 ± 1.7 (MEC*); 12.4 ± 1.1 (S100); and 12.1 ± 1.5 (S200). Both treated groups had lower Lm values and more homogeneity in the lung parenchyma compared to the MEC group: SDI = 7.5 ± 1.9 (Control); 11.3 ± 2.5 (MEC*), 5.8 ± 1.9 (S100); and 6.7 ± 1.7 (S200) (*P < 0.05 versus all the other groups). CONCLUSIONS: Animals treated with surfactant showed significant improvement in pulmonary mechanics and more regularity of the lung parenchyma in comparison to untreated animals. There was no difference in results after treatment with either of the doses used.

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Published

2004-01-01

Issue

Section

Original Research

How to Cite

Lyra, J. C., Mascaretti, R. S., Precioso, A. R., Chang, Y. C., Costa, M. T. Z. da, Vaz, F. A. C., Okay, Y., & Rebello, C. M. (2004). Different doses of exogenous surfactant for treatment of meconium aspiration syndrome in newborn rabbits . Revista Do Hospital Das Clínicas, 59(3), 104-112. https://doi.org/10.1590/S0041-87812004000300003