Effect of Protocolized Magnesium Replacement on Mortality and Atrial Fibrillation in Critically Ill Patients

In patients with critical illness, such as severe infections, heart attacks, or respiratory failure, most intensive care units (ICUs) measure magnesium levels and give supplemental doses of magnesium when levels are below certain targets. However, the best targets are unknown. The goal of this clinical trial is to study protocols for magnesium supplementation in people with critical illness, comparing a protocol with higher target level to a protocol with a lower target level. The main question this study aims to answer is whether magnesium supplementation protocols targeting a higher or lower level lead to better 30-day survival and less atrial fibrillation. Participants will not have to do any specific tasks, undergo any additional tests, or complete any surveys.