Surfactant improves lung function and mitigates bacterial growth in immature ventilated rabbits with experimentally induced neonatal group B streptococcal pneumonia.
OBJECTIVE
To study the influence of surfactant on lung function and bacterial proliferation in immature newborn rabbits with experimental group B streptococcal (GBS) pneumonia.


METHODS
Preterm rabbit fetuses (gestational age 28 days) underwent tracheotomy and were mechanically ventilated in a warmed body plethysmograph that permitted measurement of lung-thorax compliance. Fifteen minutes after the onset of ventilation the animals received either GBS or saline intratracheally; at 30 minutes, a bolus of saline or 200 mg/kg of a porcine surfactant (Curosurf) was administered via the airway. Bacterial proliferation was evaluated in lung homogenate at the end of the experiments and the results expressed as mean log10 cfu/g lung (SD). Animals receiving only saline (n = 20) or saline and surfactant (n = 20) served as controls.


RESULTS
The average survival time was about three hours in all groups. Infected animals receiving surfactant (n = 22) had significantly less bacterial growth (9.09 (0.45) vs 9.76 (0.91)) and improved lung function (compliance: 0.61 (0.14) vs 0.34 (0.19) ml/kg. cm H2O) than infected rabbits receiving saline at 30 minutes (n = 22).


CONCLUSIONS
Surfactant improves lung function and mitigates bacterial growth in preterm rabbits infected with group B streptococci.
Herting
E
E
Department of Paediatrics, University of Göttingen, Germany.
Sun
B
B
Jarstrand
C
C
Curstedt
T
T
Robertson
B
B
D000818:Animals; D000831:Animals, Newborn; D001688:Biological Products; D004195:Disease Models, Animal; D008168:Lung / Q000503:physiopathology*; D008170:Lung Compliance; D010743:Phospholipids; D018410:Pneumonia, Bacterial / Q000503:physiopathology / Q000628:therapy*; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D011817:Rabbits; D013290:Streptococcal Infections / Q000503:physiopathology / Q000628:therapy*; D013292:Streptococcus agalactiae / Q000254:growth & development
D001688:Biological Products; D010743:Phospholipids; D011663:Pulmonary Surfactants; C068291:poractant alfa