Comparison of respiratory function and fluid balance in very low birthweight infants given artificial or natural surfactant or no surfactant treatment

J Perinat Med. 1998;26(6):469-74. doi: 10.1515/jpme.1998.26.6.469.


Exogenous surfactant administration improves respiratory function. The speed of improvement appears greater if a natural rather than an artificial surfactant is used, our aim was to determine if that effect was explained by differences in fluid balance, evidenced by the timing of the diuresis onset (i.e. output greater than input). Thirty infants (median gestational age 29 weeks), 10 given an artificial surfactant (Exosurf), 10 a natural surfactant (Survanta) and 10 no surfactant (controls) were studied. During the first three days, compliance and functional residual capacity were measured daily, arginine vasopressin (AVP) levels estimated on days 1, 3 and 5 and, in 8-hourly intervals, the median arterial/alveolar ratio was calculated for each individual and urine output and fluid input recorded. Throughout the three-day period, the median arterial/alveolar ratio was always significantly higher in the control compared to the two surfactant groups (p < 0.05). On day 3 the Exosurf-treated babies had lower compliance and functional residual capacity (p < 0.05) than the other two groups. Neither the timing of diuresis onset, timing of the maximum diuresis nor the AVP levels, however, differed significantly between the groups. Only surfactant treatment and type of surfactant, but not the timing of the onset nor of the maximum diuresis, related significantly to changes in lung function. These results do not support the hypothesis that differences in fluid balance explain differences in the lung function improvement rate following natural and artificial surfactant.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Products*
  • Diuresis
  • Drug Combinations
  • Fatty Alcohols / therapeutic use
  • Gestational Age
  • Humans
  • Infant, Newborn
  • Infant, Premature / physiology*
  • Infant, Very Low Birth Weight / physiology*
  • Phosphorylcholine*
  • Polyethylene Glycols / therapeutic use
  • Positive-Pressure Respiration
  • Pulmonary Surfactants / therapeutic use*
  • Respiration, Artificial
  • Respiratory Physiological Phenomena*
  • Water-Electrolyte Balance


  • Biological Products
  • Drug Combinations
  • Fatty Alcohols
  • Pulmonary Surfactants
  • Phosphorylcholine
  • Polyethylene Glycols
  • dipalmitoylphosphatidylcholine, hexadecanol, tyloxapol drug combination
  • beractant