title: Amniotic fluid shake test versus lecithin-sphingomyelin ratio in the antenatal prediction of respiratory distress syndrome.
abstract: Surfactant content of 211 amniotic fluid samples raken between 28 and 42 weeks' gestations was determined by the shake test. Parallel with this also the lecithin/sphingomyelin (L/S) ratio was measured in 99 cases. When the test was positive no respiratory distress syndrome (RDS) occurred, while 25 RDS (53.34%) developed in 46 newborns with negative test and 8 RDS (15.38%) in 52 newborns with intermediate test. RDS was observed in all cases when the L/S ratio was below 1.5. At L/S ratios between 1.5 and 2.0, RDS appeared in 50% of the negative tests and 20% of the intermediate tests. However, when the L/S ratio was over 2.0 no RDS occured even in the case of negative tests. For the clinical praxis the positive test gives an exact information; no RDS is to be expected in such cases. In the case of a negative test, however, the authors think is necessary also to determine the L/S ratio.
mesh_terms: D000653:Amniotic Fluid / Q000032:analysis*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis / Q000379:methods; D011663:Pulmonary Surfactants / Q000032:analysis*; D012127:Respiratory Distress Syndrome, Newborn / Q000175:diagnosis*; D013109:Sphingomyelins / Q000032:analysis*
chemical_list: D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D013109:Sphingomyelins