Ricardo Horacio Fescina

Arterial blood pressure standards during normal pregnancy and their relation with mother-fetus variables

The purpose of our work was to study blood pressure variations during pregnancy in a normal Latin American population from Argentina and Uruguay; to investigate blood pressure variations according to maternal age, parity, or pregnancy weight gain; and to correlate diastolic blood pressure levels in the last trimester of pregnancy with newborn birth weight. This prospective study included follow-up throughout gestation of 249 normal pregnant women (129 nulliparous and 120 multiparous) with a weekly blood pressure control under the same experimental conditions. Our results demonstrate that there is only a low correlation between maternal age and diastolic blood pressure, but no correlation was found with systolic blood pressure; maternal weight gain correlates with blood pressure changes; no correlation was found between gestational age and blood pressure, although an increasing tendency in systolic and diastolic blood pressure was found toward the end of gestation; and a significant correlation was observed between birth weight and average diastolic blood pressure during the third trimester. These findings demonstrate the potential significance of the use of standard blood pressure data from normal pregnant women for the future clinical evaluation of our population.

Safety of Benzathine Penicillin for Preventing Congenital Syphilis: A Systematic Review

Objective To estimate the risk of serious adverse reactions to benzathine penicillin in pregnant women for preventing congenital syphilis. Methods We searched for clinical trials or cohorts that assessed the incidence of serious adverse reactions to benzathine penicillin in pregnant women and the general population (indirect evidence). MEDLINE, EMBASE, Scopus and other databases were searched up to December 2012. The GRADE approach was used to assess quality of evidence. Absolute risks of each study were calculated along with their 95% confidence intervals (95% CI). We employed the DerSimonian and Laird random effects model in the meta-analyses. Results From 2,765 retrieved studies we included 13, representing 3,466,780 patients. The studies that included pregnant women were conducted to demonstrate the effectiveness of benzathine penicillin: no serious adverse reactions were reported among the 1,244 pregnant women included. In the general population, among 2,028,982 patients treated, 4 died from an adverse reaction. The pooled risk of death was virtually zero. Fifty-four cases of anaphylaxis were reported (pooled absolute risk = 0.002%; 95% CI: 0%–0.003% I2 = 12%). From that estimate, penicillin treatment would be expected to result in an incidence of 0 to 3 cases of anaphylaxis per 100,000 treated. Any adverse reactions were reported in 6,377 patients among 3,465,322 treated with penicillin (pooled absolute risk = 0.169%; 95% CI: 0.073%–0.265% I2 = 97%). The quality of evidence was very low. Conclusion Studies that assessed the risk of serious adverse events due to benzathine penicillin treatment in pregnant women were scarce, but no reports of adverse reactions were found. The incidence of severe adverse outcomes was very low in the general population. The risk of treating pregnant women with benzathine penicillin to prevent congenital syphilis appears very low and does not outweigh its benefits. Further research is needed to improve the quality of evidence.

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.

Ultrasonic patterns of intrauterine fetal growth in a Latin American country

Head circumference and its cross-sectional area, biparietal and fronto-occipital diameters, abdominal circumference and its cross-sectional area, and the transverse and anteroposterior diameters were measured in 30 healthy single fetuses from normal pregnancies by means of ultrasound. The 5th, 50th and 95th percentiles of distance and velocity curves are described. The comparison of the values of a perimeter (abdominal or cephalic) measured directly from the photograph or calculated by the ellipse formula, showed a straight correlation. The use of the ellipse formula in current practice may simplify and reduce the cost of this technology.

Interpregnancy interval and perinatal outcomes across Latin America from 1990 to 2009: a large multi-country study.

To determine the relationship of interpregnancy interval with maternal and offspring outcomes.

Maternal mortality in Latin America and the Caribbean

Mortality and serious morbidity as a result of childbirth not only cause human suffering but they also have implications for the social and economic development of a society. In less-developed countries economic development is hindered by high rates of maternal neonatal and infant deaths. These deaths which affect socially deprived sections of society are associated with malnutrition low levels of education poverty and poor access to health-care services. Initiatives are needed for Latin American and Caribbean countries to reduce maternal mortality to the targeted rate of 15.6 per 100000 live births which rate Costa Rica has already achieved. Local programs need to be intensified to improve the basic development of socially excluded communities. Health-related interventions are also needed to control the biological factors associated with maternal mortality. Moreover evidence indicates that the majority of causes of high maternal mortality can be prevented by simple and low-cost interventions.

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.

Oxygen transport in newborns at different gestational ages

Oxygen (O2) transport was assessed through the affinity between O2 and hemoglobin (Hb) in 123 newborns of 28 to 40 week gestational ge, with a minimum of 9 newborns for each gestational age group (see table). In order to assess the O2-Hb affinity, we studied the correlation between the pO2 and the Hb saturation for each gestational age, obtaining estimates of the oxy-hemoglobin dissociation curves corresponding to each gestational age (see fig. 3). The pO2 levels corresponding to the 50% saturation (P50) for each gestational age were estimated from there. All newborns were from single vaginal deliveries with no fetal distress before birth and with an adequate weight for gestational age. The latter was calculated according to the date of the last menstrual period (78% of the cases), echography (10.6% of the cases) or neonatal physical exam (11.4% of the cases). A P50 vs. gestational age linear regression showed a high determination rate (r2 = 0.957, p less than 0.00001) (see fig. 2) which supports the hypothesis of the P50 linear growth; decrease in the Hb-O2 affinity with increasive gestational age (Hb-O2 affinity is different in newborns of different gestational ages). With these results one may conclude that the Hb-O2 uptake varies according to gestational age (P50 changes linearly as gestational age increases) and that a single measurement of pO2 in a newborns, blood does not accurately evaluate the amount of O2 that is transported to the tissues, because the transport capacity depends, among other factors, upon gestational age. The Hb saturation better represents the amount of O2 that can get to the cell level.(ABSTRACT TRUNCATED AT 250 WORDS)