Acute effects of dihydralazine mesylate, furosemide, and metoprolol on maternal hemodynamics in pregnancy-induced hypertension

The use of loop diuretics in the context of hypertensive disorders of pregnancy: a systematic review and meta-analysis

AIMS

Addressing volume expansion may improve the management of hypertension across the pregnancy continuum. We conducted a systematic review to summarize the evidence on the use of loop diuretics in the context of hypertensive disorders during pregnancy and the postpartum period.

METHODS AND RESULTS

Medline, Embase, Cochrane library, ClinicalTrials.gov, and Google Scholar were searched for original research articles published up to 29 June 2021. Of the 2801 results screened, 15 studies were included: eight randomized controlled trials, six before-after studies, and one cohort study. Based on random effects meta-analysis of before-after studies, antepartum use of loop diuretics was associated with lower DBP [mean difference -17.73 mmHg, (95% confidence intervals -34.50 to -0.96); I2 = 94%] and lower cardiac output [mean difference -0.75 l/min, (-1.11 to -0.39); I2 = 0%], with no difference in SBP, mean arterial pressure, heart rate, or total peripheral resistance. Meta-analysis of randomized controlled trials revealed that postpartum use of loop diuretics was associated with decreased need for additional antihypertensive patients [relative risk 0.69, (0.50-0.97); I2 = 14%], and an increased duration of hospitalization [mean difference 8.80 h, (4.46-13.14); I2 = 83%], with no difference in the need for antihypertensive therapy at hospital discharge, or persistent postpartum hypertension.

CONCLUSION

Antepartum use of loop diuretics lowered DBP and cardiac output, while their postpartum use reduced the need for additional antihypertensive medications. There was insufficient evidence to suggest a clear benefit. Future studies focusing on women with hypertensive pregnancy disorders who may most likely benefit from loop diuretics are required.

Complex Management of Nephrotic Syndrome and Kidney Failure during Pregnancy in a Type 1 Diabetes Patient: A Challenging Case

Pregnancy with chronic kidney disease is challenging, and patients with diabetic nephropathy are at particular risk of a rapid kidney function decline during pregnancy. While indications for the management of pregnant patients with initial diabetic nephropathy are widely available in the literature, data on patients with severe nephrotic syndrome and kidney function impairment are lacking, and the decision on whether and when dialysis should be initiated is not univocal. We report a type 1 diabetes patient who started pregnancy with a severe nephrotic syndrome and shifted from CKD stage 3b to stage 5 during pregnancy. The management was complicated by a fetal heart malformation and by poorly controlled diabetes. The evidence for and against starting dialysis was carefully evaluated, and the choice of strict nephrological and obstetrical monitoring, nutritional management, and diuretic treatment made it possible to avoid dialysis in pregnancy, after ruling out pre-eclampsia. This experience enables examination of some open issues and contributes to the discussion of when to start dialysis in pregnancy.

Cardiovascular Pharmacotherapeutic Considerations During Pregnancy and Lactation

Table 2 summarizes the recommendations regarding the use of cardiovascular drugs during pregnancy and lactation.

The effect of valvular heart disease on maternal and fetal outcome of pregnancy

OBJECTIVES

The aim of this study was to evaluate the association between valvular heart disease (VHD) and maternal and fetal outcome in a relatively large group of patients by a comparison to a well-matched control group.

BACKGROUND

Available information regarding outcome of pregnancy in women with VHD is limited to either anecdotal reports or small series of patients without an appropriate control. A better understanding of the effects of valvular abnormalities on pregnancy outcome is of value for risk assessment and the design of a therapeutic plan.

METHODS

A retrospective evaluation was made of 66 pregnancies in 64 women with VHD cared for at a tertian-care center with a high-risk obstetrics/cardiology clinic and 66 individually selected normal pregnant women matched in age, ethnicity, obstetrical and medical history, time of initial prenatal care, and year of pregnancy.

RESULTS

Women with VHD had a significantly higher incidence of congestive heart failure (38% vs. 0%; p < 0.00001), arrhvthmias (15% vs. 0%, p = 0.002), initiation or increase of cardiac medications (41% vs. 2%, p < 0.0001), and hospitalizations (35% vs. 2%, p < 0.0001). Mortality, however, occurred in only one patient (2% vs. 0%, p = NS) with aortic stenosis (AS) and coarctation. Moreover, VHD also had an effect on fetal outcome, resulting in an increased preterm delivery (23% vs. 6%, p = 0.03), intrauterine growth retardation (21% vs. 0%, p < 0.0001), and a reduced birth weight (2,897 +/- 838 g vs. 3,366 +/- 515 g, p = 0.0003). Increased maternal morbidity and unfavorable fetal outcome were seen mostly in patients with moderate and severe mitral stenosis (MS) and AS.

CONCLUSIONS

Pregnancy in women with MS and AS is associated with marked increase in maternal morbidity and unfavorable effect on fetal outcome, which are related to severity of disease. Despite high maternal morbidity, mortality is rare.

Differential effects of intravenous hydralazine on myoendometrial and placental blood flow in hypertensive pregnant ewes

OBJECTIVE

The differential vasoactive effects of hydralazine on the uteroplacental vascular bed were studied.

STUDY DESIGN

After control measurements were taken, near-term chronically prepared pregnant sheep were continuously infused with angiotensin II. Maternal arterial pressure was increased by 32 mm Hg. Hydralazine was then administered; the effects on regional resistance and blood flow were evaluated with a radionuclide-labeled microsphere technique. Analysis of variance for repeated measures was used to compare observations.

RESULTS

When compared with the hypertensive state, hydralazine caused the following changes by 40 minutes (mean +/- SEM): Although maternal blood pressure fell 31% +/- 5% (p = 0.0005), placental blood flow was unchanged, total uteroplacental blood flow increased 24% +/- 8% (p = 0.03), total uteroplacental resistance decreased 43% +/- 4% (p = 0.0002), placental resistance decreased 19% +/- 9% (p = 0.01), myoendometrial blood flow increased 390% +/- 82% (p = 0.0005), and myoendometrial resistance decreased 82% +/- 4% (p = 0.0005).

CONCLUSIONS

In angiotensin II-induced hypertensive ewes, hydralazine is an effective dilator of the uteroplacental vascular bed and can maintain placental blood flow while blood pressure.

The effect of pregnancy on renal function: physiology and pathophysiology

Marked changes in renal function occur with pregnancy. We present a summary of these changes in this review and give insight into possible mechanisms if they are known. Controversies exist regarding the therapy of pregnancy-induced hypertension and asymptomatic and recurrent bacteriuria. The current views on these topics are given. Specific renal diseases are summarized, including transplantation, and optimum management strategies and maternal and fetal prognosis during pregnancy are given.

Acute hypertensive crisis in pregnancy

Severe pre-eclampsia is a state of acute afterload increase where compensation may be total by use of the Frank-Starling mechanism and/or increased adrenergic drive, or may be uncompensated in a patient with limited or exhausted preload reserve. As such, we are presented with a diverse group of patients and antihypertensive therapy ideally should be individualized. In reality we are dealing with a complex situation because of the presence of the fetus raising concerns about direct effects on the fetus as well as on uteroplacental blood flow. This limits our choice of agents to those with extensive use in pregnancy except in complicated or resistant cases. For these reasons, hydralazine is the antihypertensive agent of choice for treatment of acute hypertensive emergencies in pregnancy. In the complicated case other agents such as sodium nitroprusside or nitroglycerin may be more appropriate and, in these cases, hemodynamic monitoring should be performed to allow not only greater safety, but also to tailor therapy to the individual hemodynamic profile.