A Comparative Study of Intravenous Labetalol With Oral Antihypertensive Combination Nifedipine and Alpha-Methyldopa in the Acute Management of High Blood Pressure in Severe Pregnancy-Induced Hypertension Patients

Abstract

Normal pregnancy is characterised by unique physiological changes. It is mandatory for an anaesthesiologist to understand these changes and their anaesthetic implications. Pregnancy-Induced Hypertension (PIH) is a disorder of unknown aetiology affecting 5-10% of all pregnancies characterised by the development of hypertension with proteinuria after 20 weeks of gestation. Hypertension is defined as sustained systolic pressure of at least 140 mmHg or a sustained diastolic pressure of at least 90 mmHg that occurs after 20 weeks of gestation in a woman with previously normal blood pressure. Maternal complications of severe pregnancy-induced hypertension include pulmonary oedema, intracerebral haemorrhage, and renal failure. Foetal complications include Intrauterine Growth Retardation (IUGR), perinatal mortality. Management of severe pregnancy-induced hypertension requires multidisciplinary approach. Definitive treatment consists of termination of pregnancy along with prevention of seizures and control of blood pressure. The drugs used in the control of blood pressure are oral anti-hypertensives like alpha-methyldopa and intravenous agents like hydralazine, labetalol, nitroglycerin, etc. Intravenous labetalol injection is a unique drug with both alpha and beta-adrenergic receptor blocking properties. It has both blood pressure and heart rate reducing properties. This makes it a good choice in treating high blood pressure in severe pregnancy-induced hypertension patients. AIM OF THE STUDYThe aim of this study is to find out and compare the efficacy of intravenous labetalol injection with the routinely used regimen of oral antihypertensives combination of tablet alpha-methyldopa and tablet nifedipine in the acute management of high blood pressure in severe pregnancy-induced hypertension patients. METHODSForty patients with severe PIH were randomly allocated to receive either inj. labetalol (Group L) (n=20) or oral antihypertensives combination namely Tab. nifedipine 10 mg and Tab. alpha-methyldopa 500 mg (Group A) (n=20). Administration of drugs with respect to Age, Gravid Status, Blood Pressure, Urine Albumin Levels, Side Effects, Drug Dosage, Additional Treatment, Prolongation of Pregnancy, Foetal monitoring, mode of termination, Indication of Caesarean Section, and APGAR Scores were studied. The statistical level of significance was taken at P <0.05. RESULTSOral antihypertensive combination of tablets alpha-methyldopa and nifedipine achieved blood pressure control that often necessitated intravenous nitroglycerin as rescue drug. Intravenous labetalol achieves adequate and faster blood pressure control with better heart rate maintenance than the routinely used oral antihypertensive combination. There was no difference in the groups with regard to obstetric intervention. Neonatal outcomes were same in both groups. CONCLUSIONIn conclusion, intravenous labetalol achieves adequate and faster blood pressure control with better heart rate maintenance than the routinely used oral antihypertensive combination of tablets alpha...