Sublingual nifedipine compared with intravenous hydrallazine in the acute treatment of severe hypertension in pregnancy: potential for use in rural practice

OBJECTIVES: The purposes of this study were to compare the efficacy of sublingual nifedipine with intravenous hydrallazine in the control of acute hypertension of pregnancy and to make a preliminary assessment whether sublingual nifedipine could be recommended for use by midwives faced with severe hypertension in pregnancy in a rural setting.

METHODS: Subjects were 200 consecutive patients admitted to Kuala Tereng-ganu General Hospital, Malaysia with severe hypertension in pregnancy between August 1989 and June 1990. Admission criteria were an ongoing viable pregnancy more than 28 weeks and diastolic blood pressure (DBP) more than 120 mmHg. The patients were randomly divided into 2 groups. In group I, sublingual nifedipine 5 mg was administered and repeated after 15 minutes if DBP > 120 mmHg; and in group II hydrallazine 5 mg was intravenously injected and repeated after 15 minutes if DBP > 120 mmHg. Both groups were put on hydrallazine infusion if DBP > 120 mmHg after 30 minutes. The Chi-square test was used for analysis with significance at p < 0.05.

RESULTS: There was no statistical difference in the efficacy of therapy for decreasing blood pressure between the 2 groups. The groups were comparable by age, parity, gestational age at presentation, birth weight of infants, incidence of postpartum haemorrhage and fetal distress. Caesarian section rates were similar. In the observational studies on nurses administering the drugs, no significant difficulties were observed.

CONCLUSION: Sublingual nifedipine was comparable to IV hydrallazine in the treatment of acute hypertension of pregnancy. Nurses were able to administer lingual nifedipine without difficulty.