[Factors affecting clinical response to surfactant therapy in neonates with severe respiratory distress syndrome].
Clinical data from a multicenter, nonrandomized clinical trial (phase II) of surfactant therapy in 206 neonates with severe respiratory distress syndrome were evaluated by logistic risk models to identify factors that might affect response to surfactant therapy as well as outcome. Based on the magnitude and duration of initial response to a single post-ventilatory dose of Surfactant-TA, the response patterns were classified into three categories: A) immediate and sustained response, B) immediate response, relapse, and recovery, and C) poor or no response. Neonates with response A had significantly better outcome than those with response C. When the neonates with response A were combined with those with response B, surfactant treatment was successful in 89% of the neonates, with a 90% survival rate in this series. The risk variables strongly associated with "non responders" were low pretreatment values for arterial pH (less than or equal to 7.25), blood pressure, and a 5-minute Apgar score (less than or equal to 6). All of these factors are known to be related to perinatal events including an intercurrent episode of hypoxia during the first hours of life, and modify the course of "pure" respiratory distress syndrome, in which the surfactant deficiency is the primary factor. Some of these factors affecting the response to the surfactant can be eliminated by improving perinatal care including maternal transport, prevention of birth asphyxia and initial stabilization of the neonates with respect to the cardiocirculatory system, and by treating with surfactant at or soon after birth.
Fujiwara
T
T
Department of Pediatrics, Iwate Medical University, Morioka, Japan.
Chida
S
S
Konishi
M
M
D001724:Birth Weight; D006801:Humans; D007231:Infant, Newborn; D010100:Oxygen / Q000097:blood; D011379:Prognosis; D011650:Pulmonary Alveoli / Q000378:metabolism*; D011663:Pulmonary Surfactants / Q000172:deficiency; D012044:Regression Analysis; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality; D013501:Surface-Active Agents / Q000627:therapeutic use*
D011663:Pulmonary Surfactants; D013501:Surface-Active Agents; D010100:Oxygen