Assessing maternal cardiac function by obstetricians: technique and reference ranges

Fetuses with deceleration of growth improve their growth following maternal rest

OBJECTIVE

The purpose of this study was to determine if fetuses with deceleration of growth velocity resulting in an EFW <10th percentile increase their growth above the 10th percentile following 2 weeks of maternal rest in the left lateral recumbent position.

METHODS

This was a retrospective observational study of 265 fetuses with the prenatal diagnosis of an EFW <10th percentile. Fetuses were classified by four definitions of abnormal growth velocity: (1) a growth velocity less than 20 g/day, (2) 30 percentile decrease in the EFW, (3) 50 percentile decrease in the EFW, and (4) abnormal growth trajectory. Once the fetuses were identified with an EFW <10th percentile the patient was requested to begin 2 weeks of rest in the left lateral recumbent position during her waking hours following which the EFW was reassessed 2 week later to determine the effect of maternal rest on the EFW.

RESULTS

Irrespective of the four types of decreased growth velocity described in the methods section, there was as significant increase (p < 0.001) in the EFW following 2 weeks of maternal rest as follows: (1) growth less than 20 g/day (75%); (2) decrease of 30 or more EFW percentiles (79%); (3) decrease of 50 or more EFW percentiles (64%); and abnormal growth trajectory (77%).

CONCLUSIONS

This suggests an important role of increased maternal cardiac output as the result of resting in the left lateral recumbent position that may be associated with improved fetal growth. These observations should be the basis for future prospective randomized trials to test this hypothesis.

Acute Aortic Dissection during Pregnancy: Hideous Clinical Quandaries with Young Lives on the Line-The Role of Hereditary Genetic Syndromes

Objective: Acute aortic dissection is a rare but frequently fatal aortic catastrophe with high morbidity and mortality. Especially in pregnant patients, acute dissection is often misdiagnosed putting two lives on the line. Due to its scarcity, only case reports have been reported. The aim of this study is to analyze the time of aortic dissection during the course of pregnancy and the outcome of emergency surgery in pregnant women with and without hereditary connective tissue disorder. Methods: We retrospectively reviewed all acute aortic dissections (type A and B) who underwent emergency aortic surgery at our institution between 1994 and 2022 and identified 13 patients with acute aortic dissection during pregnancy or directly postpartum. Mann-Whitney U and Fisher's exact tests were used for statistical analysis. Results: Of the 13 included patients, 5 had a genetic syndrome. These patients were significantly younger at the time of dissection and at an earlier stage of pregnancy (second trimester). Even though operative and in-house mortality was zero, we lost one patient on postoperative day 14 due to rupture of the aortic root after transfer to another hospital. Survival of neonates was 77% including two aborted pregnancies. Conclusions: Surgical treatment of acute aortic dissection during pregnancy can be performed with excellent operative mortality for the mothers and satisfying survival of their neonates. In patients with genetic syndrome, dissection occurs during the early second trimester, whereas non-syndromic patients experience acute dissection in the late third trimester. Long-term follow-up is essential for timely re-intervention, if needed.

Maternal rest improves growth in small-for-gestational-age fetuses (<10th percentile)

BACKGROUND

Optimal management of fetuses diagnosed as small for gestational age based on an estimated fetal weight of <10th percentile represents a major clinical problem. The standard approach is to increase fetal surveillance with serial biometry and antepartum testing to assess fetal well-being and timing of delivery. Observational studies have indicated that maternal rest in the left lateral position improves maternal cardiac output and uterine blood flow. However, maternal bed rest has not been recommended based on the results of a randomized clinical trial that showed that maternal rest does not improve fetal growth in small-for-gestational-age fetuses. This study was conducted to revisit this question.

OBJECTIVE

This study aimed to determine whether maternal bed rest was associated with an increase in the fetal biometric parameters that reflect growth after the diagnosis of a small-for-gestational-age fetus.

STUDY DESIGN

A retrospective study was conducted on fetuses who were diagnosed as small for gestational age because of an estimated fetal weight of <10th percentile for gestational age. The mothers were asked to rest in the left lateral recumbent position. Fetal biometry was performed 2 weeks after the diagnosis. All fetuses before entry into the study had a previous ultrasound that demonstrated an estimated fetal weight of >10th percentile. To assess the response to bed rest, the change in fetal biometric parameters (estimated fetal weight, head circumference, abdominal circumference, and femur length) after the recommendation of bed rest was computed for 2 periods: (1) before the diagnosis of a weight of <10th percentile vs at the time of diagnosis of a weight of <10th percentile and (2) at the time of diagnosis of a weight of <10th percentile vs 2 weeks after maternal bed rest. For repeated measures, proportions were compared using the McNemar test, and percentile values were compared using the Bonferroni Multiple Comparison Test. A P value of <.05 was considered significant. To describe changes in the estimated fetal weight without bed rest, 2 control groups in which the mothers were not placed on bed rest after the diagnosis of a small-for-gestational-age fetus were included.

RESULTS

A total of 265 fetuses were observed before and after maternal bed rest. The following were observed in this study: (1) after 2 weeks of maternal rest, 199 of 265 fetuses (75%) had a fetal weight of >10th percentile; (2) the median fetal weight percentile increased from 6.8 (interquartile range, 4.4-8.4) to 18.0 (interquartile range, 9.5-29.5) after 2 weeks of bed rest; (3) similar trends were noted for the head circumference, abdominal circumference, and femur length. In the groups of patients who were not asked to be on bed rest, a reassignment to a weight of >10th percentile at a follow-up examination only occurred in 7 of 37 patients (19%) in the Texas-Michigan group and 13 of 111 patients (12%) in the Colorado group compared with the bed rest group (199/265 [75%]) (P<.001).

CONCLUSION

Patients who were prescribed 2 weeks of bed rest after the diagnosis of a fetal weight of <10th percentile had an increase in weight of >10th percentile in 199 of 265 fetuses (75%). This increase in fetal weight was significantly higher than that in the 2 control groups in which bed rest was not prescribed. This observation suggests that bed rest improves fetal growth in a subset of patients.

Obstetric echodynamics: Approaching a new field of multidisciplinary action

Maternal cardiovascular adaptation during pregnancy is essential for fetal development. Structural and functional changes, including increased blood volume, heart rate, and myocardial hypertrophy, are crucial for optimal tissue perfusion. Recent evidence supports viewing maternal and fetal cardiovascular systems as a unified functional unit, emphasizing the significance of hemodynamic evaluation in pregnancy. Some obstetrical syndromes result from maladaptive maternal cardiovascular responses. Non-invasive hemodynamic tests, like transthoracic echocardiography, aid in distinguishing phenotypes, guiding tailored management strategies for hypertensive disorders. Establishing obstetric hemodynamics as a multidisciplinary field, termed "Obstetric Echodynamics," promises improved clinical care through standardized practices, interdisciplinary cooperation, and enhanced education.