Urapidyl for hypertension control in severe pre-eclampsia: a comparative study with nicardipine

Introduction

During severe pre-eclampsia (PE), control of blood pressure (BP) is crucial in order to prevent systemic complications. Currently approved treatments such as nicardipine (N) and dihydralazine have drawbacks. Since hypertension in PE is associated with increased sympathetic activity, urapidil (U), a peripheral α1 antagonist, has potential for BP control in PE, but no controlled comparison of U with N is available. This preliminary randomized controlled trial aims to compare efficacy and safety of U and N to reduce BP in severe PE.

Methods

After IRB approval and signed informed consent, 18 women with severe PE without previous antihypertensive treatment were randomized to U or N groups. The therapeutic goal was to achieve a mean BP (MBP) between 105 and 125 mmHg. The U patients first received U 6.25 mg boluses every 5 minutes until the diastolic BP dropped below 105 mmHg, followed by a 4 mg/hour infusion adjusted as needed. In the N group, patients first received a N 1 γ/kg/minute infusion until a 15% reduction in mean BP, followed by a N 0.75 γ/kg/minute infusion adjusted as needed. Non-invasive BP was assessed every 5 minutes during treatment titration and then every 15 minutes. The time needed to reach the therapeutic goal was registered. The main endpoint was the achievement of the BP goal in 2 hours or less. Tolerance was assessed by the number of episodes of hypotension (HO) (defined as MBP below 100 mmHg) and side effects. Severe HO, defined as MBP below 80 mmHg or two episodes of HO, was considered as treatment failure and led to exclusion. Further assessment was limited to safety, amount of ocytocics used and neonatal evaluation by ICU paediatricians until discharge from ICU. Results were compared using analysis of variance. Side effects were compared with the chi-square test.

Results

One U patient was excluded from the efficacy assessment due to a protocol violation. The main endpoint was reached in all 17 patients, after 50 minutes in both groups. During the first 2 hours, the needed treatment adjustment median value was 1 (0 to 10) in the U group and 1 (0 to 13) in the N group. Side effects attributable to the study treatment were observed in six of the nine cases in the N group and in one of the nine cases in the U group (P < 0.02). There were no severe side effects or neonatal side effects.

Conclusions

No difference in efficacy could be shown in this preliminary series. Both treatments were easy to titrate. Fewer side effects were recorded in the U group. Further studies are needed in order to compare U and N.