Alex C. Vidaeff

Chronic Renal Disease in Pregnancy

The purpose of this review was to examine the impact of varying degrees of renal insufficiency on pregnancy outcome in women with chronic renal disease. Our search of the literature did not reveal any randomized clinical trials or meta-analyses. The available information is derived from opinion, reviews, retrospective series, and limited observational series. It appears that chronic renal disease in pregnancy is uncommon, occurring in 0.03–0.12% of all pregnancies from two U.S. population-based and registry studies. Maternal complications associated with chronic renal disease include preeclampsia, worsening renal function, preterm delivery, anemia, chronic hypertension, and cesarean delivery. The live birth rate in women with chronic renal disease ranges between 64% and 98% depending on the severity of renal insufficiency and presence of hypertension. Significant proteinuria may be an indicator of underlying renal insufficiency. Management of pregnant women with underlying renal disease should ideally entail a multidisciplinary approach at a tertiary center and include a maternal–fetal medicine specialist and a nephrologist. Such women should receive counseling regarding the pregnancy outcomes in association with maternal chronic renal disease and the effect of pregnancy on renal function, especially within the ensuing 5 years postpartum. These women will require frequent visits and monitoring of renal function during pregnancy. Women whose renal disease is further complicated by hypertension should be counseled regarding the increased risk of adverse outcome and need for blood pressure control. Some antihypertensives, especially angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers, should be avoided during pregnancy, if possible, because of the potential for both teratogenic (hypocalvaria) and fetal effects (renal failure, oliguria, and demise).

Gestational diabetes: a field of controversy.

Many clinicians in the United States routinely screen all pregnant women in their practices for gestational diabetes. Recently, the US Preventive Services Task Force re-emphasized that such screening is not supported by rigorous scientific evidence. Recommendations for diagnosis and management are based on an even scantier scientific foundation. Although this review questions several aspects of current dogma, it, too, is based on the frequently flawed existing data. It is surprising how, in spite of an abundance of published information on the subject, we continue to be ignorant of the real benefits of the widespread practice of screening and treating for gestational diabetes. The authors hope that the results of a randomized clinical trial, now in progress, will help to resolve some of the controversies surrounding gestational diabetes. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader should be able to describe the controversy surrounding the significance of gestational diabetes, to break down the data regarding the efficacy of screening for gestational diabetes, and to outline potential treatment options for gestational diabetes.

Acute hypertensive emergencies in pregnancy

Objective:Obstetrical hypertensive emergencies are life-threatening conditions involving significant risk to both the mother and fetus. Aggressive treatment of the maternal hypertensive state requires an initial consideration of the effect of treatment on the fetus, via changes to the uteroplacental circulation with treatment. The challenge then is to correct blood pressure using appropriate, safe pharmacologic agents to prevent catastrophic maternal consequences, while minimizing acute changes to placental perfusion and any corresponding fetal ill effects. Hypertension in pregnancy may be one manifestation of a multiple-system pathologic process, as is the case in preeclampsia. Blood pressure control, along with delivery, will be the first step in treating the renal, hematologic, hepatic, and cardiac dysfunction that can be seen in preeclampsia. Design:A review of medications most commonly used for hypertensive emergencies in pregnancy. Conclusions:Hypertensive emergencies in pregnancy require prompt evaluation and treatment in an intensive care setting to prevent untoward effects to both the fetus and mother.

Pregnancy in women with renal disease. Part I: general principles.

The purpose of this review is to improve the basis upon which advice on pregnancy is given to women with renal disease and to address issues of obstetric management by drawing upon the accumulated world experience. To ensure the proper rapport between the respect for patients autonomy and the ethical principle of beneficence, the review attempts to impart up-to-date, evidence-based information on the predictable outcomes and hazards of pregnancy in women with chronic renal disease. The physiology of pregnancy from the perspective of the affected kidney will be discussed as well as the principal predictors of maternal and fetal outcomes and general recommendations of management. The available evidence supports the implication that the degree of renal function impairment is the major determinant for pregnancy outcome. In addition, the presence of hypertension further compounds the risks. On the contrary, the degree of proteinuria does not demonstrate a linear correlation with obstetric outcomes. Management and outcome of pregnancies occurring in women on dialysis and after renal transplant are also discussed. Although the outcome of pregnancies under chronic dialysis has markedly improved in the past decade, the chances of achieving a viable pregnancy are much higher after transplantation. But even in renal transplant recipients, the rate of maternal and fetal complications remains high, in addition to concerns regarding possible adverse effects of immunosuppressive drugs on the developing embryo and fetus.

Potential Risks and Benefits of Antenatal Corticosteroid Therapy Prior to Preterm Birth in Pregnancies Complicated by Severe Fetal Growth Restriction

The antepartum administration of fluorinated corticosteroids for fetal maturation represents the most important clinical contribution in the battle against prematurity. This treatment reduces the risk of neonatal death and handicap. It is also known that on corticosteroid exposure, fetuses are subjected to transiently increased physiologic and metabolic demands. Healthy fetuses are able to cope, although emerging evidence suggests this may not be the case with severely growth-restricted fetuses. This review presents evidence of efficacy and safety pertaining to corticosteroid administration in fetal growth restriction–affected pregnancies, offers guidance to clinicians, and points out questions that still need answers.

Antenatal corticosteroids after preterm premature rupture of membranes.

Preterm premature rupture of membranes (PPROM) is an obstetrical complication associated with high neonatal morbidity and mortality. The current management of PPROM focuses on neonatal benefit and includes the ancillary use of corticosteroids for fetal maturation. The purpose of this work was to provide a comprehensive and unbiased review of the available literature on prenatal administration of corticosteroids in conditions of PPROM, and to address the rationale and the relevant supporting evidence for this practice. We conclude that the cumulative level I evidence indicates a definite beneficial effect of corticosteroids in conditions of PPROM.

Continuous glucose monitoring in diabetic women following antenatal corticosteroid therapy: A pilot study

To compare the timing, duration, and severity of corticosteroid-associated hyperglycemia in pregnant women with and without diabetes mellitus (DM). An observational study was conducted of pregnant women with DM and controls who received corticosteroids. Median glucose levels were calculated over 4-hour intervals after the first dose of corticosteroid with a continuous glucose monitor. A glucose level increase of at least 15% above baseline was considered significant. Nine pregnant women participated in this study (six with DM and three without DM). Elevations of glucose levels occurred at hour 20, 44, and 68 in both groups and lasted for up to 4 hours. In those with DM, glucose levels increased 33 to 48%, whereas in those without DM, glucose levels rose 16 to 33%. Several, relatively short episodes of glucose elevation occur in response to corticosteroids, and are more pronounced in diabetic women.

Management strategies for the prevention of preterm birth: Part II - Update on cervical cerclage.

Purpose of review Cerclage was devised more than 50 years ago based on the hypothesis that for some women, weakness or malfunction of the cervix has a causative role in the pathway to preterm birth (PTB). There have been many theories around the concept of cervical insufficiency but not much in the way of convincing evidence. The purpose of this review was to follow the recent developments in risk identification and prognostication of PTB in connection with appropriately targeted prophylactic interventions. Recent findings Sonographic cervical length measurement has emerged as an effective prognosticator for PTB in all populations studied so far, independently of obstetric history, consequently deriving a wider applicability than other predictors of PTB. However, the mechanisms leading to cervical shortening are poorly understood, and it cannot be assumed that all cases with a short cervix would benefit from cerclage. Specific conditions may actually reduce the efficacy and advisability of cerclage. For this reason, attempts have been made recently to further characterize the short cervix, leading to the conclusion that only women with a short cervix in the absence of infection/inflammation may be candidates for cerclage. Furthermore, two recent randomized trials of cerclage in women with short cervix on a second trimester ultrasound suggested a benefit with cerclage in PTB rate reduction only in those cases with a cervical length of less than 15 mm. Summary The existent literature has treated PTB prevention focusing exclusively on either progesterone use or cerclage, leaving the practitioners without any guidance on when to proceed with medical or surgical prophylaxis. Understanding that high-risk populations are not homogeneous and no single-approach modality is likely to be generally applicable, we have combined the available evidence on both progesterone and cerclage to provide guidance on how to identify subgroups of women at significantly increased risk for PTB and how to preferentially consider progesterone versus cerclage.

In vitro quantification of dexamethasone-induced surfactant protein B expression in human lung cells.

Objective: To determine whether the effect of a single 48-h exposure to dexamethasone in human lung cells is limited to 7–8 days.Study design: We used the NCI-H441 cell line, in which stability can be maintained beyond 7 days. The outcome was the stimulatory effect of dexamethasone on surfactant protein B (SP-B) gene transcription as expressed by SP-B mRNA accumulation. The experiment was conducted five times, in parallel with control. SP-B mRNA was determined at baseline, 48 h after dexamethasone exposure, and at 48-h intervals thereafter, up to 14 days, by quantitative reverse transcription polymerase chain reaction. Comparisons were made by the Mann-Whitney test.Results: In conditions of our experiment, the inductive profile of SP-B mRNA after exposure to dexamethasone demonstrated maximal stimulation at 48 h (13-fold over control). Subsequently, there was a decline in mRNA, with return to near control levels by day 8, suggesting reversibility of dexamethasone action.Conclusion: Our data support the view that the surfactant-inducing properties of corticosteroids are limited to 7–8 days.

Antenatal corticosteroids for fetal maturation in women at risk for preterm delivery

The available data unambiguously support the beneficial, short-term fetal effects of antenatal corticosteroids in women at risk for preterm delivery. There are still several incompletely addressed questions, including the use of corticosteroids in women with preterm premature rupture of membranes, the optimal corticosteroid preparation to be used, and the impact of repeated dosing. These issues are discussed in this review from the perspective of recent scientific evidence on the mechanisms responsible for positive short-term effects on survival and possible harmful long-term effects.