Drayton A Hammond1, Jelena Stojakovic2, Niranjan Kathe3, Julie Tran4, Oktawia A Clem3, Kristina Erbach3, Jarrod King3. 1. Department of Pharmacy, Rush University Medical Center, Chicago, IL, USA. 2. Department of Pharmacy, Central Arkansas Veterans Healthcare System, Chicago, IL, USA. 3. Department of Pharmacy Practice, University of Arkansas for Medical Sciences College of Pharmacy, Chicago, IL, USA. 4. Department of Pharmacy, Mercy Hospital, Chicago, IL, USA.
Abstract
BACKGROUND: "Rules of thumb" for the replacement of electrolytes, including magnesium, in critical care settings are used, despite minimal empirical validation of their ability to achieve a target serum concentration. This study's purpose was to evaluate the effectiveness and safety surrounding magnesium replacement in medically, critically ill patients with mild-to-moderate hypomagnesemia. METHODS: This was a single-center, retrospective, observational evaluation of episodes of intravenous magnesium replacement ordered for patients with mild-to-moderate hypomagnesemia (1.0-1.9 mEq/L) admitted to a medical intensive care unit from May 2014 to April 2016. The primary effectiveness outcome, achievement of target serum magnesium concentration (≥2 mEq/L) compared to expected achievement using a "rule of thumb" estimation that 1 g intravenous magnesium sulfate raises the magnesium concentration 0.15 mEq/L, was tested using 1-sample z test. Logistic regression analysis was conducted to assess the effect of infusion rate on target achievement. RESULTS: Of 152 days on which magnesium replacements were provided for 72 patients, a follow-up serum magnesium concentration was checked within 24 hours in 89 (58.6%) episodes. Of these 89 episodes, serum magnesium concentration reached target in only 49 (59.8%) episodes compared to an expected 89 (100%; P < .0001). There was no significant association between infusion rate and achievement of the target serum magnesium concentration (odds ratio: 0.962, 95% confidence interval: 0.411-2.256). CONCLUSIONS: Medically, critically ill patients who received nonprotocolized magnesium replacement achieved the target serum magnesium concentration less frequently than the "rule of thumb" estimation predicted.
BACKGROUND: "Rules of thumb" for the replacement of electrolytes, including magnesium, in critical care settings are used, despite minimal empirical validation of their ability to achieve a target serum concentration. This study's purpose was to evaluate the effectiveness and safety surrounding magnesium replacement in medically, critically ill patients with mild-to-moderate hypomagnesemia. METHODS: This was a single-center, retrospective, observational evaluation of episodes of intravenous magnesium replacement ordered for patients with mild-to-moderate hypomagnesemia (1.0-1.9 mEq/L) admitted to a medical intensive care unit from May 2014 to April 2016. The primary effectiveness outcome, achievement of target serum magnesium concentration (≥2 mEq/L) compared to expected achievement using a "rule of thumb" estimation that 1 g intravenous magnesium sulfate raises the magnesium concentration 0.15 mEq/L, was tested using 1-sample z test. Logistic regression analysis was conducted to assess the effect of infusion rate on target achievement. RESULTS: Of 152 days on which magnesium replacements were provided for 72 patients, a follow-up serum magnesium concentration was checked within 24 hours in 89 (58.6%) episodes. Of these 89 episodes, serum magnesium concentration reached target in only 49 (59.8%) episodes compared to an expected 89 (100%; P < .0001). There was no significant association between infusion rate and achievement of the target serum magnesium concentration (odds ratio: 0.962, 95% confidence interval: 0.411-2.256). CONCLUSIONS: Medically, critically ill patients who received nonprotocolized magnesium replacement achieved the target serum magnesium concentration less frequently than the "rule of thumb" estimation predicted.
Authors: Niranjani Prasad; Aishwarya Mandyam; Corey Chivers; Michael Draugelis; C William Hanson; Barbara E Engelhardt; Krzysztof Laudanski Journal: J Pers Med Date: 2022-04-20