Magnesium supplementation in mechanical ventilated critically ill adult patients

Recent studies have described the change in blood magnesium levels following its administration to children, pregnant women and patients who have had cardiac surgery. We wish to study the effects of IV magnesium supplementation in the general adult ICU population, specifically those who are receiving both ventilatory and blood pressure support. We also wish to study the effect of kidney function on IV magnesium supplementation in these patients. We aim to assess the blood and urine levels of magnesium immediately prior to and during magnesium replacement, administered as a 1-hour bolus followed by a 24-hour infusion, in 30 critically ill patients admitted to the Austin Hospital ICU. Blood and urine samples are already routinely collected in ICU patients for monitoring purposes; it is not anticipated that the additional tests would cause any harm. Retrospectively, we will also record basic demographic and admission details about the patients so that we can appropriately describe the study cohort. It is hoped that the information gathered from this study would fill a fundamental gap in our knowledge of IV magnesium supplementation in the critically unwell patient, helping clinicians to standardise their practice regarding the usage of magnesium.