Oral nifedipine versus intravenous labetalol in hypertensive urgencies and emergencies of pregnancy: a randomized clinical trial

Optimal treatment for women with acute hypertension in pregnancy; a randomized trial comparing intravenous labetalol versus nicardipine

OBJECTIVES

Blood pressure control in severe hypertension of pregnancy is crucial for mother and neonate. In absence of evidence, guidelines recommend either intravenous labetalol or nicardipine. We compared the effectiveness and safety of these two drugs in women with severe hypertension in pregnancy.

STUDY DESIGN

We performed an open label randomized controlled trial. Women with a singleton pregnancy complicated by severe hypertension (systolic ≥ 160 mmHg and/or diastolic ≥ 110 mmHg) requiring intravenous antihypertensive treatment were randomized to intravenous labetalol or intravenous nicardipine. The primary outcome was a composite adverse neonatal outcome defined as severe Respiratory Distress Syndrome (RDS), Broncho Pulmonary Dysplasia (BPD), Intraventricular Hemorrhage (IVH) IIB or worse, Necrotizing Enterocolitis (NEC), or perinatal death defined as fetal death or neonatal death before discharge from the neonatal intensive care unit (NICU). Based on a power analysis, we estimated that 472 women (236 per group) needed to be included to detect a difference of 15% in the primary outcome with 90% power. The study was halted prematurely at 30 inclusions because of slow recruitment and trial fatigue.

RESULTS

Between August 2018 and April 2022, we randomized 30 women of which 16 were allocated to intravenous nicardipine and 14 to intravenous labetalol. The composite adverse neonatal outcome was not significantly different between the two groups (25 % versus 43 % OR 0.28 (95 % CI 0.05-1.43), p = 0.12)). Respiratory distress syndrome occurred more often in the labetalol group than in the nicardipine group (42.9 % versus 12.5 %). Neonatal hypoglycemia occurred more often in the nicardipine group than in the labetalol group (31 % versus 7 %). Time until blood pressure control was faster in women treated with nicardipine than in women treated with labetalol (45 (15-150 min vs. 120 (60-127,5) min).

CONCLUSION

In our prematurely halted small RCT, we were unable to provide evidence for the optimal choice of treatment for severe hypertension to improve neonatal outcome and/or to obtain faster blood pressure control. Differences in Respiratory distress syndrome and neonatal hypoglycemia between the groups might be the result of coincidental finding due to the small groups included in the study. A larger randomized trial would be needed to determine the safest and most efficacious (intravenous) therapy for severe hypertension in pregnancy. This study emphasizes the challenges of conducting a RCT for the optimal treatment for these women.

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.

Comparative efficacy and safety of oral nifedipine with other antihypertensive medications in the management of hypertensive disorders of pregnancy: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Hypertensive disorders of pregnancy are the most frequently occurring medical condition during pregnancy, resulting in fetal and/or maternal morbidity and mortality. This meta-analysis compared the efficacy and safety of nifedipine with other antihypertensive medications used in hypertensive disorders of pregnancy.

METHODOLOGY

A comprehensive search was performed using PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar. The meta-analysis was carried out using Review Manager Software, and the pooled effect estimate was generated as standardized mean difference and odds ratio with 95% confidence interval and two-sided P -value.

RESULTS

The meta-analysis was comprised of 22 randomized control trials with 2595 participants. It was found that meantime and number of doses required to achieve target blood pressure were lower in the nifedipine group ( P  < 0.05). Even though it is statistically insignificant, fetal APGAR (Appearance, Pulse, Grimace, Activity, and Respiration) scores less than seven favors nifedipine intervention. Furthermore, none of the fetal or maternal secondary outcomes were found significant.

CONCLUSION

Nifedipine was found to be more effective than other antihypertensive medications to reduce blood pressure, particularly in patients with severe hypertension. However, future clinical studies, including real-world data are necessary to establish the safety profile of nifedipine concerning the fetal outcomes in hypertensive pregnant women.

Preeclampsia: Pathophysiology and management

Preeclampsia is a pregnancy-related multisystem disorder, frequently encountered pregnancy-related medical complications next to gestational diabetes mellitus. It is the onset of hypertension during pregnancy. The preeclampsia can be of two types, placental or maternal preeclampsia. Among these two types former, i.e., placental preeclampsia is more severe than the latter. According to the recent survey by National Health Portal of India, the incidence of preeclampsia is about 8-10 % among pregnant women. Though our understanding of preeclampsia has improved in recent years, the development and interpretation of the clinical tests remain difficult for preeclampsia. Hence, we have made an attempt to understand the pathophysiology, associated conditions/consequences, treatment and management/prevention of the condition in this review.

Oral Nifidepine versus IV labetalol in severe preeclampsia: A randomized control trial

Objective:

To compare oral Nifidepine and IV labetalol in terms of rapidity of BP control in severe preeclampsia.

Methods:

All patients coming to Services Hospital from March 2017 to February 2019 with diagnosis of severe preeclampsia ≥ 24 weeks gestation were randomized to either receive Nifidepine or Labetalol. Primary outcome measure was time taken to control BP and number of doses required. Secondary outcome measures were side effects of drugs, APGAR score, NICU admission and perinatal mortality.

Results:

Two hundred four patients were included in trial with 102 patients in each group. Labetalol took 22.6± 13.5minutes and Nifidepine took 22.09± 11.7 minutes to achieve target BP (p>0.05). Labetalol required 2.3± 1.58 doses and Nifidepine 2.2± 1.58 doses to control BP ( p>0.05). No maternal side effects were seen in 86 (84.31%) and 92(90.19%) patients in both groups (p>0.05). Mean gestational age at birth was 34.8 ±2.73weeks in Labetalol and 35.2±2.48 weeks in Nifidepine group (p>0.05). In labetalol group, 43 (42.15%) babies had APGAR Score < 7/10 and 23(22.54%) babies required admission to NICU while in Nifidepine group 42 (41.17%) babies had Apgar score < 7/10 & 30(29.4%) babies were admitted to NICU(p>0.05). There were 21(20.5%) perinatal deaths in labetalol Group-And 19(18.6%) in Nifidepine group (p>0.05)

Conclusion:

Oral Nifidepine and IV labetalol are equally efficacious in controlling BP in patients with severe pre eclampsia without any significant side effects.

IV labetalol and oral nifedipine in acute control of severe hypertension in pregnancy-A randomized controlled trial

OBJECTIVE

To compare the efficacy of intravenous labetalol with oral nifedipine in the treatment of severe hypertension in pregnancy with blood pressure ≥160/110 mm Hg.

DESIGN, SETTING AND PARTICIPANTS

We conducted a parallel double-blinded randomized controlled trial between December 2014 to December 2016 in 120 antenatal women of gestational age >28 weeks, admitted with severe hypertension of blood pressure ≥160/110 mm Hg to maternity ward at a tertiary hospital. The labetalol group received 20 mg initially followed by escalating doses of 40 mg, 80 mg, 80 mg and 80 mg (5 doses) every 15 min to a maximum of 300 mg. Nifedipine group received 10 mg initially followed by repeated doses of 20 mg every 15 min (total 5 doses) to a maximum of 90 mg. Vital signs were recorded every 15 min. -The time taken and the number of doses required to achieve the target blood pressure (150/100 mmHg). Survival analysis was used to compare the efficacy of treatment regimens.

RESULTS

Sixty women were randomised to each group and none were lost to follow-up. None of the patients in nifedipine group required labetalol, whereas three patients in labetalol group achieved target BP only after receiving nifedipine was administered after the maximum dose of labetalol.The mean time taken to achieve the target blood pressure in the labetalol group was higher (36.75 min) than in the nifedipine group (27.25 min) [mean difference 9.5 min,p = 0.002]. Nifedipine group required significantly lower doses (1.82 ± 0.83) as compared to labetalol (2.45 ± 1.32) [p = 0.002]. Nifedipine was 1.8 times more likely to achieve target blood pressure (Hazard Ratio = 1.8).

CONCLUSIONS

Both intravenous Labetalol and oral Nifedipine were effective in controlling blood pressure. Nifedipine reduced BP more rapidly than Labetalol. Oral Nifedipine may be a better alternative because of its ease of oral administration and a flat dosing regimen.

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.

Pre-eclampsia

Pre-eclampsia affects 3-5% of pregnancies and is traditionally diagnosed by the combined presentation of high blood pressure and proteinuria. New definitions also include maternal organ dysfunction, such as renal insufficiency, liver involvement, neurological or haematological complications, uteroplacental dysfunction, or fetal growth restriction. When left untreated, pre-eclampsia can be lethal, and in low-resource settings, this disorder is one of the main causes of maternal and child mortality. In the absence of curative treatment, the management of pre-eclampsia involves stabilisation of the mother and fetus, followed by delivery at an optimal time. Although algorithms to predict pre-eclampsia are promising, they have yet to become validated. Simple preventive measures, such as low-dose aspirin, calcium, and diet and lifestyle interventions, show potential but small benefit. Because pre-eclampsia predisposes mothers to cardiovascular disease later in life, pregnancy is also a window for future health. A collaborative approach to discovery and assessment of the available treatments will hasten our understanding of pre-eclampsia and is an effort much needed by the women and babies affected by its complications.

Oral nifedipine versus intravenous labetalol for severe hypertension during pregnancy: a systematic review and meta-analysis

BACKGROUND

Oral nifedipine is recommended along with labetalol and hydralazine for treatment of severe hypertension during pregnancy by most authorities. Although nifedipine is cheap and easily administered, the usage pattern among health care providers suggests a strong preference for labetalol despite lack of evidence for the same.

OBJECTIVES

To determine the efficacy and safety of oral nifedipine for treatment of severe hypertension of pregnancy compared with intravenous labetalol.

SEARCH STRATEGY

We systematically searched for articles comparing oral nifedipine with intravenous labetalol for the treatment of severe hypertension during pregnancy in any language, over Medline, Cochrane Central Register of Clinical Trials and Google Scholar from inception till February 2014.

SELECTION CRITERIA

We included all RCTs that compared intravenous labetalol with oral nifedipine for treatment of severe hypertension during pregnancy, addressing relevant efficacy and safety outcomes.

DATA COLLECTION AND ANALYSIS

Eligible studies were reviewed, and data were extracted onto a standard form. We used Cochrane review manager software for quantitative analysis. Data were analysed using a fixed effect model.

MAIN RESULTS

The pooled analysis of seven trials (four from developing countries) consisting of 363 woman-infant pairs showed that oral nifedipine was associated with less risk of persistent hypertension (RR 0.42, 95% CI 0.18-0.96) and reported maternal side effects (RR 0.57, 95% CI 0.35-0.94). However, on sensitivity analysis the outcome 'persistent hypertension' was no longer significant. Other outcomes did not reach statistical significance.

CONCLUSION

Oral nifedipine is as efficacious and safe as intravenous labetalol and may have an edge in low resource settings.

TWEETABLE ABSTRACT

Although studies to date are few in number and small, nifedipine shows promise for severe hypertension in pregnancy.