A randomised comparison of hydralazine and mini-bolus diazoxide for hypertensive emergencies in pregnancy: The PIVOT trial

Evaluation of antihypertensives for post partum management of hypertensive disorders of pregnancy: A systematic review and meta-analysis

BACKGROUND

There is a lack of evidence that directly shows the best antihypertensive treatment options for post partum management of the hypertensive disorders of pregnancy. Our objective was to analyze the safest and most effective antihypertensive drugs post partum for patients with hypertensive disorders of pregnancy.

METHODS

PubMed, Cochrane, and MEDLINE were searched to find relevant articles published from inception to Feb 2024. We included randomized control trials, in English, featuring a population of postnatal women with hypertensive disorders of pregnancy or postpartum women with de novo hypertension with a follow-up of up to 6 months in which any antihypertensive medication was compared with Placebo or a comparison between different doses of antihypertensives was done. The statistical analyses were conducted using Review Manager with a random-effects model.

RESULTS

Our analysis revealed that almost all antihypertensives are effective in treating postpartum hypertension. However, some medications had alternating roles in controlling specific outcomes. Using calcium channel blockers resulted in a faster time to sustain BP control than the control (SMD: -0.37; 95% CI: -0.73 to -0.01; P = 0.04). In contrast, using ACE inhibitors or ARBs demanded the use of other antihypertensives in contrast to all other drugs assessed (RR: 2.09; 95% CI: 1.07 to 4.07; P = 0.03).

CONCLUSION

Timely management of the hypertensive disorders of pregnancy postpartum is life-saving. All the traditional antihypertensives we assessed effectively manage hypertension postpartum, thus allowing the physician to tailor the particular drug regimen according to the patient's needs and comorbidities without any hindrance.

Comparing Intravenous Labetalol and Intravenous Hydralazine for Managing Severe Gestational Hypertension

Background Hypertensive disorders of pregnancy are the leading causes of both maternal morbidity and maternal mortality. Hypertensive disorders are acute obstetric emergencies, which refer to various life-threatening medical challenges known to develop during pregnancy, labor, and delivery, requiring urgent attention to reduce blood pressure (BP) for the benefit of the affected mothers and infants. Hydralazine and labetalol have been widely used as the first-line medications in the management of severe hypertension during pregnancy. However, the choice between these two drugs lacks clear evidence regarding their safety and superiority. Several studies have attempted to study intravenous (IV) labetalol versus hydralazine, but very few such comparison studies have been conducted in Africa.  Objective To compare the effectiveness of IV labetalol and IV hydralazine in reducing systolic and diastolic BP in pregnant women with severe hypertension. Also, to determine the time required for hydralazine and labetalol to lower BP to ≤150/100 mmHg, the number of doses needed for each drug, and evaluating maternal and perinatal outcomes. Study design This study employed an open-label randomized clinical trial design conducted in the labor, delivery, and antenatal ward of the Central and Stella Obasanjo Hospital in Benin City. A total of 120 women with severe pregnancy-induced hypertension were randomly assigned to two groups: Group X, consisting of 60 pregnant women, received IV hydralazine at a slow rate of 5 mg for five minutes, repeated every 20 minutes (maximum of five doses) until a blood pressure of ≤150/100 mmHg was achieved. Group Y, also consisting of 60 pregnant women, received IV labetalol in escalating doses of 25, 50, 75, 75, and 75 mg (maximum of 300 mg) every 20 minutes until the blood pressure reached ≤150/100 mmHg. Statistical analysis was performed using SPSS version 23 (IBM Inc., Armonk, New York). Result IV hydralazine achieved the target BP in an average time of 45.80 +/- 25.17 minutes, while IV labetalol took an average of 72.67 +/- 41.80 minutes (p=0.001). The number of doses required to reach the target BP differed significantly between the two drugs. Hydralazine required an average of 1.72 +/- 0.904 doses, whereas labetalol required an average of 3.72 +/- 1.782 doses (p=0.0001). While 45% of women in the hydralazine group attained the target BP with a single dose of hydralazine, only 31.1% of women in the labetalol group were able to attain the target BP with a single dose of labetalol (p=0.02). Overall, target BP was achieved in 55 out of 60 women (91.7%) who were randomized to receive IV hydralazine, whereas 45 out of 60 women (75%) who received IV labetalol achieved the target blood pressure. While hydralazine demonstrated more favorable results in terms of achieving target blood pressure, there were higher incidences of maternal adverse effects in the hydralazine group compared to the labetalol group. However, these adverse effects were not severe enough to warrant discontinuation of the medication. Conclusion IV hydralazine showed faster achievement of the target BP and a lower number of doses required compared to IV labetalol. Additionally, a higher percentage of women in the hydralazine group achieved the target BP with a single dose. However, there were more maternal adverse effects associated with hydralazine, although they were not severe. Perinatal outcomes did not differ significantly between the two groups.

Chronic Remote Ischemic Conditioning on Mild Hypertension in the Absence of Antihypertensive Medication: A Multicenter, Randomized, Double-Blind, Proof-of-Concept Clinical Trial

BACKGROUND

Exploratory studies have shown that remote ischemic conditioning (RIC) has the potential to lower blood pressure (BP). We investigated whether chronic RIC reduces BP for hypertension.

METHODS

This is a multicenter, randomized, double-blind, parallel-controlled trial. Patients with an office BP of 130/80 to 160/100 mm Hg and a 24-hour average BP ≥125/75 mm Hg not on antihypertensive medications were recruited. After a 1-week compliance screening phase, they were randomly assigned in a 1:1 ratio to receive RIC or sham RIC twice daily for 4 weeks. The primary efficacy outcome was the change in 24-hour average systolic BP from baseline to 4 weeks. Safety events were assessed over the study period.

RESULTS

Ninety-five participants were randomly allocated to the RIC (n=49) and sham RIC (n=46) groups. In the intention-to-treat analysis, the reduction in 24-hour average systolic BP was greater in the RIC group than the sham RIC group (-4.6±9.5 versus -0.9±6.8 mm Hg; baseline-adjusted between-group mean difference: -3.6 mm Hg [95% CI, -6.9 to -0.3 mm Hg]; adjusted P=0.035). The per-protocol analysis showed that 24-hour average systolic BP reduced -5.9±8.6 mm Hg in the RIC group and -0.7±6.7 mm Hg in the sham RIC group (baseline-adjusted between-group mean difference: -5.2 mm Hg [95% CI, -8.5 to -1.9 mm Hg]; adjusted P=0.002). No major adverse events were reported in both groups.

CONCLUSIONS

RIC is safe in patients with mild hypertension and may lower BP in the absence of antihypertensive medications. However, the effects of RIC on clinical outcomes in these patients require further investigation.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04915313.

Pharmaceutical administration for severe hypertension during pregnancy: Network meta-analysis

Aims: To evaluate the efficacy of different pharmacologic treatment for severe hypertension during pregnancy. Methods: Two reviewers searched Ovid MEDLINE, Ovid EMbase, and the Cochrane Library for randomized clinical trials from the establishment of the database to 15 July 2021 that were eligible for inclusion and analyzed the pharmaceuticals used for severe hypertension in pregnancy. Results: 29 relevant trials with 2,521 participants were involved. Compared with diazoxide in rate of achieving target blood pressure, other pharmaceuticals, including epoprostenol (RR:1.58, 95%CI:1.01-2.47), hydralazine\dihydralazine (RR:1.57, 95%CI:1.07-2.31), ketanserin (RR:1.67, 95%CI:1.09-2.55), labetalol (RR:1.54, 95%CI:1.04-2.28), nifedipine (RR:1.54, 95%CI:1.04-2.29), and urapidil (RR:1.57, 95%CI:1.00-2.47), were statistically significant in the rate of achieving target blood pressure. According to the SUCRA, diazoxide showed the best therapeutic effect, followed by nicardipine, nifedipine, labetalol, and nitroglycerine. The three pharmaceuticals with the worst therapeutic effect were ketanserin, hydralazine, and urapidil. It is worth noting that the high ranking of the top two pharmaceuticals, including diazoxide and nicardipine, comes from extremely low sample sizes. Other outcomes were reported in the main text. Conclusion: This comprehensive network meta-analysis demonstrated that the nifedipine should be recommended as a strategy for blood pressure management in pregnant women with severe hypertension. Moreover, the conventional pharmaceuticals, including labetalol and hydralazine, showed limited efficacy. However, it was important to note that the instability of hydralazine reducing blood pressure and the high benefit of labetalol with high dosages intakes should also be of concern to clinicians.

Antihypertensive Medications for Severe Hypertension in Pregnancy: A Systematic Review and Meta-Analysis

Background: Hypertension in pregnancy causes significant maternal and fetal mortality and morbidity. A comprehensive assessment of the effectiveness of antihypertensive drugs for severe hypertension during pregnancy is needed to make informed decisions in clinical practice. This systematic review aimed to assess the efficacy and safety of antihypertensive drugs in severe hypertension during pregnancy. Methods: A systematic review using the electronic databases MEDLINE (PubMed) and Cochrane Library was performed until August 2021. The risk-of-bias 2 tool was used to assess the risk-of-bias in each study included. Meta-analysis was conducted to assess heterogeneity and to estimate the pooled effects size. Results: Seventeen studies fulfilled the inclusion criteria and 11 were included in the meta-analysis. Nifedipine was estimated to have a low risk in persistent hypertension compared to hydralazine (RR 0.40, 95% CI 0.23–0.71) and labetalol (RR 0.71, 95% CI 0.52–0.97). Dihydralazine was associated with a lower risk of persistent hypertension than ketanserin (RR 5.26, 95% CI 2.01–13.76). No difference was found in the risk of maternal hypotension, maternal and fetal outcomes, and adverse effects between antihypertensive drugs, except for dihydralazine, which was associated with more adverse effects than ketanserin. Conclusions: Several drugs can be used to treat severe hypertension in pregnancy, including oral/sublingual nifedipine, IV/oral labetalol, oral methyldopa, IV hydralazine, IV dihydralazine, IV ketanserin, IV nicardipine, IV urapidil, and IV diazoxide. In addition, nifedipine may be preferred as the first-line agent. There was no difference in the risk of maternal hypotension, maternal and fetal outcomes, and adverse effects between the drugs, except for adverse effects in IV dihydralazine and IV ketanserin.

The flipside of hydralazine in pregnancy: A systematic review and meta-analysis

The present systematic review and meta-analysis investigated the effects of hydralazine compared with other antihypertensive drugs in maternal, perinatal and neonatal outcomes of pregnant women with hypertensive disorders. Twenty studies with 1283 participants were included. Of them, 626 received hydralazine and 657 other antihypertensive treatments, such as labetalol, nifedipine, ketanserin, diazoxide, urapidil, isradipine and epoprostenol. Women receiving hydralazine had higher heart rate (WMD: 13.4, 95%CI: 0.1 to 26.8 beats/min), increased number of adverse effects (RR: 1.21, 95%CI: 1.01 to 1.45) and gave birth to neonates of lower birthweight (WMD: 13.4, 95%CI: 0.1 to 26.8 beats/min) compared with other antihypertensive treatments at the end of follow-up. When studies, which used antihypertensive agents that are no longer indicated for hypertension in pregnancy, were excluded in the sensitivity analyses, hydralazine found not to have a statistically significant difference compared with labetalol and nifedipine regarding the reduction of maternal blood pressure (WMD: 1.72, 95%CI: -1.47 to 4.9 mmHg for systolic, WMD: 0.26, 95%CI: -1.75 to 2.28 mmHg for diastolic), maternal heart rate (WMD: 13.56, 95%CI: -5.62 to 32.74 beats/min), low birthweight (WMD: -88.62, 95%CI: -243.24 to 66 beats/min) and adverse events (RR: 1.19, 95%CI: 0.99 to 1.43). Hydralazine seems not to be inferior compared to labetalol and nifedipine for safety and efficacy.

Current and emerging pharmacotherapy for emergency management of preeclampsia

INTRODUCTION

Preeclampsia is a disease specific to pregnancy characterised by new onset hypertension with maternal organ dysfunction and/or fetal growth restriction. It remains a major cause of maternal and perinatal morbidity and mortality. For fifty years, antihypertensives have been the mainstay of treating preeclampsia, reducing maternal morbidity and mortality. With increased knowledge of the mechanisms underlying the disease has come opportunities for novel therapies that complement antihypertensives by protecting the maternal vasculature. Areas covered: In this review, the authors consider, in detail, the antihypertensives commonly used today in the emergency care of women with severe preeclampsia. They also review less common anti-hypertensive agents and discuss the role of magnesium sulphate in the management of preeclampsia and the prevention of eclampsia. Finally, they explore novel therapeutics for the acute management of preeclampsia. Expert opinion: The rapid control of maternal hypertension will, and must, remain the mainstay of emergency treatment for women with severe preeclampsia. The role of magnesium sulphate as a primary prevention for eclampsia is context dependant and should not displace a focus on correcting blood pressure safely. The exploration of novel adjuvant therapies will likely allow us to prolong pregnancy longer and improve perinatal outcomes safely for the mother.

Drugs for treating severe hypertension in pregnancy: a network meta-analysis and trial sequential analysis of randomized clinical trials

AIMS

Several antihypertensive drugs are used in the treatment of severe hypertension in pregnancy. The present study is a network meta-analysis comparing the efficacy and safety of these drugs.

METHODS

Electronic databases were searched for randomized clinical trials comparing drugs used in the treatment of severe hypertension in pregnancy. The number of women achieving the target blood pressure (BP) was the primary outcome. Doses required and time taken for achieving the target BP, failure rate, and incidences of maternal tachycardia, palpitation, hypotension, headache, and neonatal death and stillbirth were the secondary outcomes. Mixed treatment comparison pooled estimates were generated using a random-effects model. Odds ratios for the categorical and mean difference for the numerical outcomes were the effect estimates.

RESULTS

Fifty-one studies were included in the systematic review and 46 in the meta-analysis. No significant differences in the number of patients achieving target BP was observed between any of the drugs. Diazoxide [-15 (-20.6, -9.4)], nicardipine [-11.8 (-22.3, -1.2)], nifedipine/celastrol [-19.3 (-27.4, -11.1)], nifedipine/vitamin D [-17.1 (-25.7, -9.7)], nifedipine/resveratrol [-13.9 (-22.6, -5.2)] and glyceryl trinitrate [-33.8 (-36.7, -31)] were observed to achieve the target BP (in minutes) more rapidly than hydralazine. Nifedipine required fewer doses than hydralazine for achieving the target BP. Glyceryl trinitrate and labetalol were associated with fewer incidences of tachycardia and palpitation respectively than hydralazine. Trial sequential analysis concluded adequate evidence for hydralazine and nifedipine compared with labetalol. Moderate quality of evidence was observed for direct comparison estimate between labetalol and hydralazine but was either low or very low for other comparisons.

CONCLUSION

The present evidence suggests similar efficacy between nifedipine, hydralazine and labetalol in the treatment of severe hypertension in pregnancy. Subtle differences may exist in their safety profile. The evidence is inadequate for other drugs.

Postpartum management of hypertensive disorders of pregnancy: a systematic review

OBJECTIVES

Hypertensive disorders of pregnancy (HDP) affect one in ten pregnancies and often persist postpartum when complications can occur. We aimed to determine the effectiveness and safety of pharmacological interventions, other interventions and different care models for postpartum hypertension management.

DESIGN

A systematic review was undertaken. Nine electronic databases, including Medline, were searched from inception to 16 March 2017. After duplicate removal, 4561 records were screened. Two authors independently selected studies, extracted study characteristics and data, and assessed methodological quality.

SETTING

Randomised controlled trials, case-control studies and cohort studies from any country and healthcare setting.

PARTICIPANTS

Postnatal women with HDP.

INTERVENTIONS

Therapeutic intervention for management of hypertension, compared with another intervention, placebo or no intervention.

PRIMARY AND SECONDARY OUTCOME MEASURES

Outcome data were collected for maternal mortality and severe morbidity; systolic, diastolic and mean arterial blood pressure (BP) control; and safety data. Secondary outcome data collected included the length of postnatal hospital stay and laboratory values.

RESULTS

39 studies were included (n=2901). Results were heterogeneous in terms of intervention, comparison and outcome requiring a narrative approach. There were insufficient data to recommend any single pharmacological intervention. 18 studies reported calcium-channel blockers, vasodilators and beta-blockers lowered BP postpartum. 12 of these reported safety data. Limited data existed regarding management in the weeks following hospital discharge. Neither loop diuretics (three studies) nor corticosteroids (one study) produced clinical benefit. Uterine curettage significantly reduced BP over the first 48 hours postpartum (range 6-13 mm Hg) compared with standard care (eight studies), with safety data only reported by four of eight studies.

CONCLUSION

There was insufficient evidence to recommend a particular BP threshold, agent or model of care, but three classes of antihypertensive appeared variably effective. Further comparative research, including robust safety data, is required. Curettage reduced BP, but without adequate reporting of harms, so it cannot currently be recommended.

Anesthetic considerations in HELLP syndrome

BACKGROUND

HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) is an obstetric complication with heterogonous presentation and multisystemic involvement. It is characterized by microangiopathic hemolytic anemia, elevated liver enzymes by intravascular breakdown of fibrin in hepatic sinusoids and reduction of platelet circulation by its increased consumption.

METHODS

In terms of these patients' anesthetic management, it is essential to consider some details: (1) effective, safe perioperative management by a multidisciplinary approach, and quick, good communication among clinical specialists to achieve correct patient management; (2) neuroaxial block, particularly spinal anesthesia, is the first choice to do the cesarean if there is only moderate, but not progressive thrombocytopenia; (3) if a general anesthesia is required, it is necessary to control the response to stress produced by intubation, especially in patients with either severe high blood pressure or neurological signs, or to prevent major cerebral complications; (4) invasive techniques, e.g., as tracheostomy, arterial, and deep-vein canalization, should be considered; (5) if contraindication for neuroaxial anesthesia exists, rapid sequence intubation with general anesthesia should be regarded as an emergency in patients with full stomach; (6) increased risk of difficult airways should be taken into account.

RESULTS

Optimal patient management can be chosen after considering the risks and benefits of each anesthetic technique, and based on good knowledge of these patients' pathophysiological conditions.

CONCLUSION

Later, close patient monitoring is recommended for potential development of hemorrhagic complications, disseminated intravascular coagulation (DIC), or eclampsia.

SOMANZ guidelines for the management of hypertensive disorders of pregnancy 2014

This guideline is an evidence based, practical clinical approach to the management of Hypertensive Disorders of Pregnancy. Since the previous SOMANZ guideline published in 2008, there has been significant international progress towards harmonisation of definitions in relation to both the diagnosis and management of preeclampsia and gestational hypertension. This reflects increasing knowledge of the pathophysiology of these conditions, as well as their clinical manifestations. In addition, the guideline includes the management of chronic hypertension in pregnancy, an approach to screening, advice regarding prevention of hypertensive disorders of pregnancy, and discussion of recurrence risks and long term risk to maternal health. The literature reviewed included the previous SOMANZ Hypertensive Disorders of Pregnancy guideline from 2008 and its reference list, plus all other published National and International Guidelines on this subject. Medline, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Registry of Controlled Trials (CCRCT), National Institute for Health and Care Excellence (NICE) Evidence Search, and Database of Abstracts and Reviews of Effects (DARE) were searched for literature published between January 2007 and March, 2014.

Determinants of neonatal blood pressure

Blood pressure (BP) measurements have been increasingly used across neonatal intensive care units to determine and monitor hemodynamic status in neonates. A number of studies have attempted to derive normative blood pressure data in both preterm and term infants. However, this still remains a complex process, as several maternal and neonatal factors influence neonatal blood pressure. Maternal conditions, including hypertension and preeclampsia, seem to have some impact on neonatal BP, while maternal drugs, in particular antenatal steroids, seem to have a strong influence. Among the neonatal factors, gestational age, post-conceptual age and weight seem to have the strongest influence. The paucity of data on the short and long term effects of maternal conditions and medication on neonatal BP requires further research.

Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy

OBJECTIVE

This guideline summarizes the quality of the evidence to date and provides a reasonable approach to the diagnosis, evaluation and treatment of the hypertensive disorders of pregnancy (HDP).

EVIDENCE

The literature reviewed included the previous Society of Obstetricians and Gynaecologists of Canada (SOGC) HDP guidelines from 2008 and their reference lists, and an update from 2006. Medline, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Registry of Controlled Trials (CCRCT) and Database of Abstracts and Reviews of Effects (DARE) were searched for literature published between January 2006 and March 2012. Articles were restricted to those published in French or English. Recommendations were evaluated using the criteria of the Canadian Task Force on Preventive Health Care and GRADE.

Drugs for treatment of very high blood pressure during pregnancy

BACKGROUND

Very high blood pressure during pregnancy poses a serious threat to women and their babies. The aim of antihypertensive therapy is to lower blood pressure quickly but safety, to avoid complications. Antihypertensive drugs lower blood pressure but their comparative effectiveness and safety, and impact on other substantive outcomes is uncertain.

OBJECTIVES

To compare different antihypertensive drugs for very high blood pressure during pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (9 January 2013).

SELECTION CRITERIA

Studies were randomised trials. Participants were women with severe hypertension during pregnancy. Interventions were comparisons of one antihypertensive drug with another.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors extracted data and checked them for accuracy.

MAIN RESULTS

Thirty-five trials (3573 women) with 15 comparisons were included. Women allocated calcium channel blockers were less likely to have persistent high blood pressure compared to those allocated hydralazine (six trials, 313 women; 8% versus 22%; risk ratio (RR) 0.37, 95% confidence interval (CI) 0.21 to 0.66). Ketanserin was associated with more persistent high blood pressure than hydralazine (three trials, 180 women; 27% versus 6%; RR 4.79, 95% CI 1.95 to 11.73), but fewer side-effects (three trials, 120 women; RR 0.32, 95% CI 0.19 to 0.53) and a lower risk of HELLP (haemolysis, elevated liver enzymes and lowered platelets) syndrome (one trial, 44 women; RR 0.20, 95% CI 0.05 to 0.81).Labetalol was associated with a lower risk of hypotension compared to diazoxide (one trial 90 women; RR 0.06, 95% CI 0.00 to 0.99) and a lower risk of caesarean section (RR 0.43, 95% CI 0.18 to 1.02), although both were borderline for statistical significance.Both nimodipine and magnesium sulphate were associated with a high incidence of persistent high blood pressure, but this risk was lower for nimodipine compared to magnesium sulphate (one trial, 1650 women; 47% versus 65%; RR 0.84, 95% CI 0.76 to 0.93). Nimodipine was associated with a lower risk of respiratory difficulties (RR 0.28, 95% CI 0.08 to 0.99), fewer side-effects (RR 0.68, 95% CI 0.55 to 0.85) and less postpartum haemorrhage (RR 0.41, 95% CI 0.18 to 0.92) than magnesium sulphate. Stillbirths and neonatal deaths were not reported.There are insufficient data for reliable conclusions about the comparative effects of any other drugs.

AUTHORS' CONCLUSIONS

Until better evidence is available the choice of antihypertensive should depend on the clinician's experience and familiarity with a particular drug; on what is known about adverse effects; and on women's preferences. Exceptions are nimodipine, magnesium sulphate (although this is indicated for women who require an anticonvulsant for prevention or treatment of eclampsia), diazoxide and ketanserin, which are probably best avoided.

Prevention and treatment of postpartum hypertension

BACKGROUND

Postpartum blood pressure (BP) is highest three to six days after birth when most women have been discharged home. A significant rise in BP may be dangerous (e.g., can lead to stroke), but there is little information about how to prevent or treat postpartum hypertension.

OBJECTIVES

To assess the relative benefits and risks of interventions to: (1) prevent postpartum hypertension, by assessing whether 'routine' postpartum medical therapy is better than placebo/no treatment; and (2) treat postpartum hypertension, by assessing whether (i) one antihypertensive therapy is better than placebo/no therapy for mild-moderate postpartum hypertension; and (ii) one antihypertensive agent offers advantages over another for mild-moderate or severe postpartum hypertension.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2013), bibliographies of retrieved papers, and personal files.

SELECTION CRITERIA

For women with antenatal hypertension, trials comparing a medical intervention with placebo/no therapy. For women with postpartum hypertension, trials comparing one antihypertensive with either another or placebo/no therapy.

DATA COLLECTION AND ANALYSIS

We extracted the data independently and were not blinded to trial characteristics or outcomes. We contacted authors for missing data when possible.

MAIN RESULTS

Nine trials are included.

PREVENTION

Four trials (358 women) compared furosemide, nifedipine capsules, or L-arginine with placebo/no therapy. For women with antenatal pre-eclampsia, postnatal furosemide is associated with a strong trend towards reduced use of antihypertensive therapy in hospital.

TREATMENT

For treatment of mild-moderate postpartum hypertension, three trials (189 women) compared timolol, oral hydralazine, or oral nifedipine with methyldopa. Use of additional antihypertensive therapy did not differ between groups (risk ratio (RR) 0.92, 95% confidence interval (CI) 0.20 to 4.20; three trials), but the trials were not consistent in their effects. The drugs were well tolerated.For treatment of severe postpartum hypertension, two trials (120 women) compared intravenous hydralazine with either sublingual nifedipine or intravenous labetalol. There were no maternal deaths or hypotension. Use of additional antihypertensive therapy did not differ between groups (RR 0.58, 95% CI 0.04 to 9.07; two trials), but the trials were not consistent in their effects.

AUTHORS' CONCLUSIONS

For women with pre-eclampsia, postnatal furosemide may decrease the need for postnatal antihypertensive therapy in hospital, but more data are needed on substantive outcomes before this practice can be recommended. There are no reliable data to guide management of women who are hypertensive postpartum. Any antihypertensive agent used should be based on a clinician's familiarity with the drug. Future studies should include data on postpartum analgesics, severe maternal hypertension, breastfeeding, hospital length of stay, and maternal satisfaction with care.

How to manage hypertension in pregnancy effectively

The hypertensive disorders of pregnancy (HDP) are a leading cause of maternal mortality and morbidity in both well and under-resourced settings. Maternal, fetal, and neonatal complications of the HDP are concentrated among, but not limited to, women with pre-eclampsia. Pre-eclampsia is a systemic disorder of endothelial cell dysfunction and as such, blood pressure (BP) treatment is but one aspect of its management. The most appropriate BP threshold and goal of antihypertensive treatment are controversial. Variation between international guidelines has more to do with differences in opinion rather than differences in published data. For women with severe hypertension [defined as a sustained systolic BP (sBP) of ≥160 mmHg and/or a diastolic BP (dBP) of ≥110 mmHg], there is consensus that antihypertensive therapy should be given to lower the maternal risk of central nervous system complications. The bulk of the evidence relates to parenteral hydralazine and labetalol, or to oral calcium channel blockers such as nifedipine capsules. There is, however, no consensus regarding management of non-severe hypertension (defined as a sBP of 140-159 mmHg or a dBP of 90-109 mmHg), because the relevant randomized trials have been underpowered to define the maternal and perinatal benefits and risks. Although antihypertensive therapy may decrease the occurrence of BP values of 160-170/100-110 mmHg, therapy may also impair fetal growth. The potential benefits and risks do not seem to be associated with any particular drug or drug class. Oral labetalol and methyldopa are used most commonly, but many different β-adrenoceptor blockers and calcium channel blockers have been studied in clinical trials.

Pre-eclampsia

Pre-eclampsia remains a leading cause of maternal and perinatal mortality and morbidity. It is a pregnancy-specific disease characterised by de-novo development of concurrent hypertension and proteinuria, sometimes progressing into a multiorgan cluster of varying clinical features. Poor early placentation is especially associated with early onset disease. Predisposing cardiovascular or metabolic risks for endothelial dysfunction, as part of an exaggerated systemic inflammatory response, might dominate in the origins of late onset pre-eclampsia. Because the multifactorial pathogenesis of different pre-eclampsia phenotypes has not been fully elucidated, prevention and prediction are still not possible, and symptomatic clinical management should be mainly directed to prevent maternal morbidity (eg, eclampsia) and mortality. Expectant management of women with early onset disease to improve perinatal outcome should not preclude timely delivery-the only definitive cure. Pre-eclampsia foretells raised rates of cardiovascular and metabolic disease in later life, which could be reason for subsequent lifestyle education and intervention.

Control of hypertension in pregnancy

The hypertensive disorders of pregnancy are a leading cause of maternal mortality and morbidity. Complications are not limited to preeclampsia but also complicate both preexisting hypertension and isolated gestational hypertension. Blood pressure (BP) management is important but is only one aspect of management of the hypertensive disorders of pregnancy, which may be caused or exacerbated by underlying uteroplacental mismatch between maternal supply and fetal demand. BP treatment thresholds and goals vary in international guidelines, largely reflecting differences in opinion rather than differences in published data. Because of short-term maternal risks, there is consensus that BP should be treated when sustained at greater than or equal to 160 to 170 mm Hg systolic and/or 110 mm Hg diastolic. There is no consensus regarding management of nonsevere hypertension, and randomized controlled trials involving just over 3000 women have not clarified the relative maternal and perinatal risks and benefits. Although antihypertensive therapy may decrease transient severe maternal hypertension, therapy may also impair fetal growth and perinatal health and outcomes. The CHIPS Trial (Control of Hypertension In Pregnancy Study) is recruiting to answer this question.

The management of severe hypertension

Although definitions of severe hypertension vary, thresholds of >or=160-170 mm Hg systolic and/or >or=110 mm Hg diastolic are in most common usage. A recent focus has been placed on systolic hypertension given the increased pulse pressure in these women. In pregnancy, there is a general consensus that severe hypertension should be treated. Among woman with pre-eclampsia, attention must be paid to other end organ dysfunction, as blood pressure (BP) management is but one aspect of care. The urgency of antihypertensive therapy will depend primarily on the absolute level of BP. However, most clinicians will also consider both the rate of BP rise and the presence of maternal symptoms. Most commonly, severe hypertension is treated with parenteral labetalol or hydralazine, or oral nifedipine (capsules or PA tablet). Other options will depend on local availability. MgSO(4) should not be relied on as an antihypertensive.

Reducing stillbirths: prevention and management of medical disorders and infections during pregnancy

BACKGROUND

An estimated two-thirds of the world's 3.2 million stillbirths occur antenatally, prior to labour, and are often overlooked in policy and programs. Poorly recognised, untreated or inadequately treated maternal infections such as syphilis and malaria, and maternal conditions including hypertensive disorders, are known risk factors for stillbirth.

METHODS

We undertook a systematic review of the evidence for 16 antenatal interventions with the potential to prevent stillbirths. We searched a range of sources including PubMed and the Cochrane Library. For interventions with prior Cochrane reviews, we conducted additional meta-analyses including eligible newer randomised controlled trials following the Cochrane protocol. We focused on interventions deliverable at the community level in low-/middle-income countries, where the burden of stillbirths is greatest.

RESULTS

Few of the studies we included reported stillbirth as an outcome; most that did were underpowered to assess this outcome. While Cochrane reviews or meta-analyses were available for many interventions, few focused on stillbirth or perinatal mortality as outcomes, and evidence was frequently conflicting. Several interventions showed clear evidence of impact on stillbirths, including heparin therapy for certain maternal indications; syphilis screening and treatment; and insecticide-treated bed nets for prevention of malaria. Other interventions, such as management of obstetric intrahepatic cholestasis, maternal anti-helminthic treatment, and intermittent preventive treatment of malaria, showed promising impact on stillbirth rates but require confirmatory studies. Several interventions reduced known risk factors for stillbirth (e.g., anti-hypertensive drugs for chronic hypertension), yet failed to show statistically significant impact on stillbirth or perinatal mortality rates. Periodontal disease emerged as a clear risk factor for stillbirth but no interventions have reduced stillbirth rates.

CONCLUSION

Evidence for some newly recognised risk factors for stillbirth, including periodontal disease, suggests the need for large, appropriately designed randomised trials to test whether intervention can minimise these risks and prevent stillbirths. Existing evidence strongly supports infection control measures, including syphilis screening and treatment and malaria prophylaxis in endemic areas, for preventing antepartum stillbirths. These interventions should be incorporated into antenatal care programs based on attributable risks and burden of disease.

Medications in pregnancy and lactation: Part 2. Drugs with minimal or unknown human teratogenic effect

This is the second of a two-part series on the use of medication during pregnancy and lactation. Pregnancy risk factors together with an increased incidence of chronic diseases and the rise in mean maternal age predict an increase in medication use during gestation. However, as highlighted in the first installment of this series, relatively few medications have specifically been tested for safety and efficacy during pregnancy, and, therefore, responses to those inquiries can be uninformed and inaccurate. Whereas the first installment provided new insight into the nature of medications with known human teratogenic effects, this part concentrates on drugs with minimal or no known human teratogenic effect. It is important that clinicians become familiar with all of the aspects of the drugs they prescribe, in addition to the controversies surrounding them, through consultation with maternal-fetal medicine specialists and through references and Web sites providing up-to-date information in an effort to promote safer prescribing practices.

Drugs for treatment of very high blood pressure during pregnancy

BACKGROUND

Very high blood pressure during pregnancy poses a serious threat to women and their babies. Antihypertensive drugs lower blood pressure. Their comparative effects on other substantive outcomes, however, is uncertain.

OBJECTIVES

To compare different antihypertensive drugs for very high blood pressure during pregnancy.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (28 February 2006) and CENTRAL (The Cochrane Library 2006, Issue 2).

SELECTION CRITERIA

Studies were randomised trials. Participants were women with severe hypertension during pregnancy. Interventions were comparisons of one antihypertensive drug with another.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data.

MAIN RESULTS

Twenty-four trials (2949 women) with 12 comparisons were included. Women allocated calcium channel blockers rather than hydralazine were less likely to have persistent high blood (five trials, 263 women; 6% versus 18%; relative risk (RR) 0.33, 95% confidence interval (CI) 0.15 to 0.70). Ketanserin was associated with more persistent high blood pressure than hydralazine (four trials, 200 women; 27% versus 6%; RR 4.79, 95% CI 1.95 to 11.73), but fewer side-effects (three trials, 120 women; RR 0.32, 95% CI 0.19 to 0.53) and a lower risk of HELLP (Haemolysis, Elevated Liver enzymes and Lowered Platelets) syndrome (one trial, 44 women, RR 0.20, 95% CI 0.05 to 0.81). Labetalol was associated with a higher risk of hypotension (one trial 90 women; RR 0.06, 95% CI 0.00 to 0.99) and caesarean section (RR 0.43, 95% CI 0.18 to 1.02) than diazoxide. Data were insufficient for reliable conclusions about other outcomes. The risk of persistent high blood pressure was greater for nimodipine compared to magnesium sulphate (two trials 1683 women; 47% versus 65%; RR 0.84, 95% CI 0.76 to 0.93). Nimodipine was also associated with a higher risk of eclampsia (RR 2.24, 95% CI 1.06 to 4.73) and respiratory difficulties (RR 0.28, 95% CI 0.08 to 0.99), but fewer side-effects (RR 0.68, 95% CI 0.54 to 0.86) and less postpartum haemorrhage (RR 0.41, 95% CI 0.18 to 0.92) than magnesium sulphate. Stillbirths and neonatal deaths were not reported. There are insufficient data for reliable conclusions about the comparative effects of any other drugs.

AUTHORS' CONCLUSIONS

Until better evidence is available, the choice of antihypertensive should depend on the clinician's experience and familiarity with a particular drug, and on what is known about adverse effects. Exceptions are diazoxide, ketanserin, nimodipine and magnesium sulphate, which are probably best avoided.

Prevention and treatment of postpartum hypertension

BACKGROUND

Postpartum blood pressure (BP) is highest three to six days after birth when most women have been discharged home. A significant rise in BP may be dangerous (e.g., lead to stroke), but there is little information about how to prevent or treat postpartum hypertension.

OBJECTIVES

To assess the relative benefits and risks of interventions to: (1) prevent postpartum hypertension, by assessing whether 'routine' postpartum administration of oral antihypertensive therapy is better than placebo/no treatment; and(2) treat postpartum hypertension, by assessing whether (i) oral antihypertensive therapy is better than placebo/no therapy for mild-moderate postpartum hypertension; and (ii) one antihypertensive agent offers advantages over another for mild-moderate or severe postpartum hypertension.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (March 2004), MEDLINE (1966 to May 2003), EMBASE (1980 to January 2003), bibliographies of retrieved papers and personal files.

SELECTION CRITERIA

For women with antenatal hypertension, trials comparing a medical intervention with placebo/no therapy. For women with postpartum hypertension, trials comparing one antihypertensive with either another or placebo/no therapy.

DATA COLLECTION AND ANALYSIS

We extracted the data independently and were not blinded to trial characteristics or outcomes. We contacted authors for missing data when possible.

MAIN RESULTS

Six trials are included.

PREVENTION

Three trials (315 women; six comparisons) compared furosemide or nifedipine capsules with placebo/no therapy. There are insufficient data for conclusions about possible benefits and risks of these management strategies. Most outcomes included data from only one trial. No trial reported severe maternal hypertension or breastfeeding.

TREATMENT

In two trials (106 women; three comparisons), oral timolol or hydralazine were compared with oral methyldopa for treatment of mild to moderate postpartum hypertension. In one trial (38 women; one comparison), oral hydralazine plus sublingual nifedipine were compared with sublingual nifedipine for treatment of severe postpartum hypertension. The need for additional antihypertensive therapy did not differ between groups (relative risk 4.24, 95% confidence interval 0.96 to 18.84; three trials, N = 144 women), but three antihypertensive drugs were studied. All were well tolerated.

AUTHORS' CONCLUSIONS

There are no reliable data to guide management of women who are hypertensive postpartum or at increased risk of becoming so. If a clinician feels that hypertension is severe enough to treat, the agent used should be based on his/her familiarity with the drug. Future studies of prevention or treatment of postpartum hypertension should include information about use of postpartum analgesics and outcomes of severe maternal hypertension, breastfeeding, hospital length of stay, and maternal satisfaction with care.