Miguel Martell

Oronasopharyngeal suction at birth: Effects on arterial oxygen saturation

The effect of oronasopharyngeal suction (ONPS) on arterial oxygen saturation (SaO2) is described in a controlled study of 30 normal term newborn infants. In 15 of them, ONPS was performed immediately after birth. The SaO2 value was recorded through a pulse oximeter. The ONPS group had a significantly lower SaO2 between the first and the sixth minutes of life and took longer to reach 86% and 92% saturation. According to this study, ONPS should not be performed as a routine procedure in normal, term, vaginally born infants.

Blood acid-base balance at birth in neonates from labors with early and late rupture of membranes

The purpose of this study was to determine whether the early artificial rupture of the amniotic membranes performed to shorten the duration of an otherwise normal labor and delivery might have potentially deleterious effects on the fetus that would be reflected in the neonate. In 38 infants delivered at term, acid-base balances and O2 and CO2 pressures were obtained in umbilical arterial and venous blood at birth, prior to the first inspiration. For the purpose of the study the infants were divided into two groups: group I infants were born after a normal labor in which the amniotic membranes were permitted to rupture spontaneously at full cervical dilatation; group II infants were born after a labor in which the membranes were ruptured artificially when cervical dilatation was 4 to 5 cm. There was no evidence of fetal distress, and all infants were vigorous at birth. The pH of umbilical venous blood was greater in the group with late rupture of the membranes (fiftieth percentile [P50] = 7.36) than in those born after early amniotomy (P50 = 7.30) (p less than 0.01). The pH values of umbilical arterial blood were also higher in the group I infants (P50 = 7.31) than in those born after amniotomy (P50 = 7.25)(p less than 0.025). These differences were also observed in the 19 neonates in whom the cord was not encircled around the neck at the time of birth. The PCO2 in umbilical venous blood was less, and the hemoglobin saturation was greater (P less than 0.05) in group I infants than in those of group II. It is possible that the influence of early amniotomy on fetal pH may be deleterious in infants born after high-risk pregnancies in which the uteroplacental circulation is impaired.

Small for Dates: Evaluation of Different Diagnostic Methods

Ninety‐four high‐risk pregnancies were studied weekly in a prospective and longitudinal study. Uterine height, biparietal diameter (BPD), cranial perimeter (CrP) and abdominal perimeter (AbP) were measured. Amniotic fluid volume (AFV) was assessed. Of the sample selected, 58 neonates were appropriate for gestational age and 36 were small‐for‐date (17 symmetrical and 19 asymmetrical). The sensitivity values in diagnosis of small‐for‐dates were: 67% for BPD, 42% for CrP, 94% for AbP, 56% for Uterine Height and 28% for AFV. The specificity for the five variables ranged from about 91% to 100%. If we consider symmetrical and asymmetrical retardation separately, the sensitivity values for the former were: 94%, 77%, 100%, 77% and 24% for BPD, CrP, AbP, Uterine Height and AFV respectively. For symmetrical retardation, the sensitivity values were: 43%, 11%, 90%, 37% and 32% for BPD, CrP, AbP, Uterine Height and AFV respectively. The fetal cranial measurements were the only ones to demostrate a different pattern of evolution in symmetrical and asymmetrical small‐for‐dates. This is therefore a useful measurement in making a differential diagnosis between both retardations. The earliest diagnoses were made in the symmetrical small‐for‐date group.

Suction patterns in preterm infants

The suction pattern for breast and bottle feeding in two groups of preterm infants is described. The time elapsed between birth and the moment of suction was longer in preterm neonates born at lower gestational ages for both groups studied, breast and bottle fed (figure 1). The evolution of suckling in breastfeeding was analyzed in a composite study (longitudinal and transverse) in a group of 16 neonates starting from 32 weeks of gestation. The velocity of milk extraction during suckling varied with gestational age. It was uniform at lower gestational ages, then it became faster in the first minutes and at the 36th week, it was very similar to that of mature neonates (figure 2 and table I). The evaluation of bottle feeding was performed in a transverse study in 46 preterm neonates which had been exclusively bottle fed during 1 or 2 weeks. All of them had previously been fed using an orogastric tube. Nourishing time was shorter than in breastfeeding; the average duration was 3.7 minutes (table II). The greatest volume was ingested in the first minute, 40% (range between 44 and 25%) (figure 3). The frequency of suction did not change the duration of feeding, but it was found that the efficiency of suction (number of suctions to ingest 1 cc) was significantly lower in the first minute (Anova, p < 0.05) (figure 4).

Repeated direct fetal intravascular high-dose immunoglobulin therapy for the treatment of Rh hemolytic disease

Recently, administration of high-dose intravenous immunoglobulin (HDivIG) either to the mother or the neonate has been proposed in an effort to prevent progressive hemolysis in Rh(D) perinatal disease, but no cases have been published with direct fetal HDivIG administration. We report a case in which HDivIG was repeatedly administered by cordocentesis to a fetus affected by Rh(D) disease from 28 to 36 weeks gestation, at doses of approximately 450 mg/kg. The fetus required no transfusions, and the neonatal evolution was satisfactory. The treatment, performed at three weeks intervals, seemed to be useful in preventing fetal hemolysis. No fetal complications were present. Recurrent administration of HDivIG therapy to the fetus in cases of severe Rh(D) disease, appears to be feasible and free of serious complications to the fetus or the mother.

Intrauterine and extrauterine growth of cranial perimeter in term and preterm infants. A longitudinal study.

In this study a cranial perimeter curve was established from 13 weeks of gestation to 6 months of postnatal life. Thirty cases were studied. The intrauterine section of the curve was derived from data obtained weekly by echography. The tenth and fiftieth percentiles of fetal measurements were greater than those described by other authors, who established intrauterine growth curves with data obtained after pretermed delivery. This pattern was used to assess the cranial perimeter growth to six months of corrected age in 48 preterm neonates of appropriate weight. Their values were below the standard at birth, reaching the normal measures on the expected date of confinement.

Estimation of gestational age by the length of the dorsal spine

Gestational age assessed by dorsal spine length (DSL) was compared with that based on date of the last menstrual period (LMP). This study was performed in 70 newborn infants admitted to a neonatal intensive care unit requiring chest radiography, by which dorsal spine length was measured (figure 1). Gestational age ranged from 23 to 42 weeks. Regression analysis were performed on DSL and gestational age. Estimation error was evaluated based on the percentage of agreement in weeks (validity) and the difference in averages between both methods (accuracy) (table I and figure 2). Variations during the first week of life were also studied and no significant differences were found. For infants born at 31 weeks or less, DSL overestimated gestational age in one week. There was no differences between 32 and 36 weeks, and over 37 weeks, underestimation was one week (figure 3). With this correction a table was built estimating gestational age for different DSL; percentage of agreement was 91.4% for +/- 3 weeks (table III). This methodology assists the clinician to evaluate gestational age by an objective method, that does not vary during the first week of life and that can be obtained retrospectively.