Biomaterial Database

The prediction of fetal lung maturity from the surface tension characteristics of amniotic fluid. 1975

E Müller-Tyl, and J Lempert

In recent years fetal lung maturity has been assessed by chemical determination of lung surfactant components in the amniotic fluid. The variation in the results, however, limits the clinical usefulness of these methods. To establish reliable criteria for fetal lung maturity 98 specimens of amniotic fluid were obtained in the 23rd to 41st week of gestation and their surface properties measured in the surface balance (Fig 1). A continuous rise in surface activity of amniotic fluid was observed during this period (Fig. 2). In the evaluation of the surface activity of amniotic fluid y-min appears to be the most suitable parameter because it shows a considerable change during the course of pregnancy and has low variations (Fig. 3). In 64 prematures amniotic fluid was obtained during delivery and its surface properties measured. The correlation of clinical symptoms of the premature with y-min of the amniotic fluid makes it possible to predict the fetal lung maturity at a given y-min value (Fig. 4). When the results are arranged according to the incidence of RDS (lethal RDS, recovered from RDS and without RDS) three y-min-ranges can be clearly distinguished. When y-min of the amniotic fluid is over 27 dyn/cm the probability of lethal RDS is 100%, whereas when y-min is under 17 dyn/cm a mature lung can be expected. In the range between 27 to 17 dyn/cm any degree of lung maturity can be encountered. By division of this range in two additional ones a more accurate prediction of fetal lung maturity is possible: In the y-min-range 27-23 dyn/cm RDS-probability is approximately 70%, in the range 23-17 dyn/cm it is only 30% (Fig. 4). Measurements of surface activity of the amniotic fluid make it possible to predict fetal lung maturity and estimate RDS-probability.

UI	MeSH Term	Description	Entries
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D007234	Infant, Premature	A human infant born before 37 weeks of GESTATION.	Neonatal Prematurity,Premature Infants,Preterm Infants,Infant, Preterm,Infants, Premature,Infants, Preterm,Premature Infant,Prematurity, Neonatal,Preterm Infant
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011336	Probability	The study of chance processes or the relative frequency characterizing a chance process.	Probabilities
D011663	Pulmonary Surfactants	Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.	Surfactants, Pulmonary,Pulmonary Surfactant,Surfactant, Pulmonary
D012127	Respiratory Distress Syndrome, Newborn	A condition of the newborn marked by DYSPNEA with CYANOSIS, heralded by such prodromal signs as dilatation of the alae nasi, expiratory grunt, and retraction of the suprasternal notch or costal margins, mostly frequently occurring in premature infants, children of diabetic mothers, and infants delivered by cesarean section, and sometimes with no apparent predisposing cause.	Infantile Respiratory Distress Syndrome,Neonatal Respiratory Distress Syndrome,Respiratory Distress Syndrome, Infant
D005260	Female		Females
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages