Treatment of experimental meconium aspiration syndrome with surfactant lung lavage and conventional vs. asymmetric high-frequency jet ventilation.
Respiratory failure caused by meconium aspiration requires combined strategies. We hypothesized that surfactant lung lavage with asymmetric high-frequency jet ventilation (AHFJV) can increase the removal of meconium and improve lung function. During conventional ventilation (CV), a suspension of human meconium (25 mg/ml, 4 ml/kg) was instilled into the tracheal tube of anesthetized rabbits to cause respiratory failure. Animals were then divided into four groups: saline lavage + CV (Sal-CV), surfactant lavage + CV (Surf-CV), saline lavage + HFJV (Sal-HFJV), and surfactant lavage + HFJV (Surf-HFJV). Lung lavage (10 ml/kg in 3 portions) was performed with diluted surfactant (Curosurf, 100 mg of phospholipids/kg) or saline during CV (frequency (f), 30/min; inspiration time (Ti), 50%) or AHFJV (f, 300/min; Ti, 70%). Animals were ventilated for an additional hour with either CV or HFJV (Ti, 50%). Surfactant lavage with both CV and AHFJV removed more meconium than saline lavage. However, the highest removal was found in the Surf-HFJV group vs. all other groups (P < 0.05). The oxygenation index decreased after surfactant lavage in both groups compared to controls (P < 0.001), and more prominently in the Surf-CV group. Elimination of CO(2) was significantly higher in the Surf-HFJV group vs. all other groups (P < 0.05). The ventilation efficiency index increased after lavage in both surfactant groups vs. saline controls (P < 0.05). Dynamic lung-thorax compliance gradually increased, and right-to-left pulmonary shunts decreased in both surfactant groups vs. saline controls after lavage (P < 0.05). Combination of surfactant lavage with both CV and AHFJV was beneficial in rabbits with meconium aspiration syndrome. While AHFJV was more effective in the removal of meconium, CV had a more favorable effect on lung function in the postlavage period.
Sevecova-Mokra
Daniela
D
Department of Physiology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia. sevecova@jfmed.uniba.sk
Calkovska
Andrea
A
Drgova
Anna
A
Javorka
Michal
M
Javorka
Kamil
K
D000818:Animals; D000831:Animals, Newborn; D018893:Bronchoalveolar Lavage; D005260:Female; D006611:High-Frequency Jet Ventilation; D008168:Lung / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D008171:Lung Diseases / Q000628:therapy*; D008297:Male; D008470:Meconium / Q000737:chemistry; D023421:Models, Animal; D011659:Pulmonary Gas Exchange; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D011817:Rabbits; D012129:Respiratory Function Tests; D013577:Syndrome; D016896:Treatment Outcome
D011663:Pulmonary Surfactants