Acute and sustained effects of lucinactant versus poractant-alpha on pulmonary gas exchange and mechanics in premature lambs with respiratory distress syndrome.
BACKGROUND
Animal-derived, protein-containing surfactants seem to be superior to protein-free surfactants. Lucinactant, a synthetic surfactant containing a surfactant protein-B peptide analog, has been shown to be effective in animal models and phase II clinical trials. To date, lucinactant has not been compared with an animal-derived surfactant in a premature animal model.


OBJECTIVE
The objective was to compare the acute and sustained effects of lucinactant among premature lambs with respiratory distress syndrome (RDS) with the effects of a natural porcine surfactant (poractant-alpha).


METHODS
After 5 minutes of mechanical ventilation twin premature lambs were assigned randomly to the lucinactant group (30 mg/mL, 5.8 mL/kg) or the poractant-alpha group (80 mg/mL, 2.2 mL/kg). Heart rate, systemic arterial pressure, arterial pH, blood gas values, and lung mechanics were recorded for 12 hours.


RESULTS
Baseline fetal pH values were similar for the 2 groups (pH 7.27). After 5 minutes of mechanical ventilation, severe RDS developed (pH: <7.08; Paco2: >80 mm Hg; Pao2: <40 mm Hg; dynamic compliance: <0.08 mL/cm H2O per kg). After surfactant instillation, similar improvements in gas exchange and lung mechanics were observed for the lucinactant and poractant-alpha groups at 1 hour (pH: 7.3 +/- 0.1 vs 7.4 +/- 0.1; Paco2: 8 +/- 18 mm Hg vs 40 +/- 8 mm Hg; Pao2: 167 +/- 52 mm Hg vs 259 +/- 51 mm Hg; dynamic compliance: 0.3 +/- 0.1 mL/cm H2O per kg vs 0.3 +/- 0.1 mL/cm H2O per kg). The improvements in lung function were sustained, with no differences between groups. Cardiovascular profiles remained stable in both groups.


CONCLUSIONS
Among preterm lambs with severe RDS, lucinactant produced improvements in gas exchange and lung mechanics similar to those observed with a porcine-derived surfactant.
Gastiasoro-Cuesta
Elena
E
Department of Pediatrics, Hospital de Cruces, University of the Basque Country, Barakaldo, Bizkaia, Spain.
Alvarez-Diaz
Francisco J
FJ
Rey-Santano
Carmen
C
Arnaiz-Renedo
Arantxa
A
Loureiro-Gonzalez
Begoña
B
Valls-i-Soler
Adolf
A
D000818:Animals; D000831:Animals, Newborn; D001688:Biological Products / Q000627:therapeutic use*; D001784:Blood Gas Analysis; D001794:Blood Pressure; D004338:Drug Combinations; D005233:Fatty Alcohols / Q000627:therapeutic use*; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D007231:Infant, Newborn; D010715:Phosphatidylglycerols / Q000627:therapeutic use*; D010743:Phospholipids / Q000627:therapeutic use*; D011506:Proteins / Q000627:therapeutic use*; D011659:Pulmonary Gas Exchange; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy* / Q000503:physiopathology; D012756:Sheep
D001688:Biological Products; D004338:Drug Combinations; D005233:Fatty Alcohols; D010715:Phosphatidylglycerols; D010743:Phospholipids; D011506:Proteins; C502722:lucinactant; C068291:poractant alfa