Magnesium sulphate for prevention of eclampsia: are intramuscular and intravenous regimens equivalent? A population pharmacokinetic study. Issue 7 (26th March 2013)

• Record Type: Journal Article
• Authors: Salinger, DH; Mundle, S; Regi, A; Bracken, H; Winikoff, B; Vicini, P; Easterling, T
• Is Part Of: BJOG. Volume 120:Issue 7(2013:Jul.)
• Page Start: 894
• Page End: 900
• Publication Date: 2013-03-26
• Subjects: Obstetrics -- Periodicals; Gynecology -- Periodicals; 618
• DOI: 10.1111/1471-0528.12222
• Languages: English
• ISSNs: 1470-0328

Abstract

<abstract abstract-type="main" id="bjo12222-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="bjo12222-sec-0001" sec-type="section"> <title>Objective</title> <p>To compare magnesium sulphate concentrations achieved by intramuscular and intravenous regimens used for the prevention of eclampsia.</p> </sec> <sec id="bjo12222-sec-0002" sec-type="section"> <title>Setting</title> <p>Low‐resource obstetric hospitals in Nagpur and Vellore, India.</p> </sec> <sec id="bjo12222-sec-0003" sec-type="section"> <title>Population</title> <p>Pregnant women at risk for eclampsia due to hypertensive disease.</p> </sec> <sec id="bjo12222-sec-0004" sec-type="section"> <title>Methods</title> <p>A pharmacokinetic study was performed as part of a randomised trial that enrolled 300 women comparing intramuscular and intravenous maintenance regimens of magnesium dosing. Data from 258 enrolled women were analysed in the pharmacokinetic study. A single sample was drawn per woman with the expectation of using samples in a pooled data analysis.</p> </sec> <sec id="bjo12222-sec-0005" sec-type="section"> <title>Main outcome measures</title> <p>Pharmacokinetic parameters of magnesium distribution and clearance.</p> </sec> <sec id="bjo12222-sec-0006" sec-type="section"> <title>Results</title> <p>Magnesium clearance was estimated to be 48.1 dl/hour, volume of distribution to be 156 dl and intramuscular bioavailability to be 86.2%. The intramuscular regimen produced higher initial serum concentrations, consistent with a substantially larger loading dose. At steady state, magnesium concentrations in the intramuscular and intravenous groups were comparable. With either regimen, a substantial number of women would be expected to have serum concentrations lower than those generally held to be therapeutic.</p> </sec> <sec id="bjo12222-sec-0007" sec-type="section"> <title>Conclusions</title> <p>Clinical implications were that a larger loading dose for the intravenous regimen should be considered; where feasible, individualised dosing of magnesium sulphate would reduce the variability in serum concentrations and might result in more women with clinically effective magnesium concentrations; and lower dose magnesium suphate regimens should be considered with caution.</p> </sec> </abstract>