Exosurf rescue surfactant improves high ventilation-perfusion mismatch in respiratory distress syndrome.
OBJECTIVE
To assess ventilation/perfusion (VA/Q) mismatch of the high type, following rescue surfactant therapy for respiratory distress syndrome.


OBJECTIVE
Surfactant therapy reduces such mismatch.


METHODS
Randomized, double-blind, placebo-controlled study, assessing VA/Q with the arterial-alveolar difference of CO2 tension (P(a-A)CO2). This difference was determined with capnometry and arterial blood gases, using the equation: P(a-A)CO2 equals arterial CO2 minus alveolar CO2 partial pressure.


METHODS
A level III nursery.


METHODS
Ten intubated infants with respiratory distress syndrome.


METHODS
Infants were randomized to each receive two doses of surfactant or two doses of air placebo.


RESULTS
P(a-A)CO2 improved after surfactant and worsened after placebo (P = 0.0021), comparing slopes of 12-hr regression lines. A similar pattern occurred with oxygenation. These changes in P(a-A)CO2 and in oxygenation were minimally correlated within the surfactant group.


CONCLUSIONS
Exosurf rescue surfactant reduced VA/Q mismatch of the high type, over several hours.
Billman
D
D
Department of Pediatrics, Medical College of Wisconsin, Milwaukee.
Nicks
J
J
Schumacher
R
R
D000403:Airway Resistance / Q000187:drug effects* / Q000502:physiology; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004338:Drug Combinations; D005233:Fatty Alcohols / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects* / Q000502:physiology; D010767:Phosphorylcholine; D011092:Polyethylene Glycols / Q000494:pharmacology / Q000627:therapeutic use*; D011652:Pulmonary Circulation / Q000187:drug effects* / Q000502:physiology; D011659:Pulmonary Gas Exchange / Q000187:drug effects* / Q000502:physiology; D011663:Pulmonary Surfactants / Q000494:pharmacology / Q000627:therapeutic use*; D012044:Regression Analysis; D012119:Respiration / Q000187:drug effects* / Q000502:physiology; D012127:Respiratory Distress Syndrome, Newborn / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D013997:Time Factors
D004338:Drug Combinations; D005233:Fatty Alcohols; D011663:Pulmonary Surfactants; D010767:Phosphorylcholine; D011092:Polyethylene Glycols; C047049:dipalmitoylphosphatidylcholine, hexadecanol, tyloxapol drug combination