Impaired diaphragmatic excursion following magnesium sulfate administration in patients with preeclampsia with severe features: a prospective observational study.

Magnesium sulfate is recognized for its muscular relaxant properties on both smooth and skeletal muscles; nevertheless, there are no prior studies examining the impact of magnesium administration on diaphragmatic movement, namely diaphragmatic excursion. Therefore, we aimed to evaluate diaphragmatic excursion as assessed by ultrasound before and after magnesium sulfate administration. Patients with a diagnosis of preeclampsia with severe features were screened for eligibility. Forty-seven patients with preeclampsia with severe features were included and available for final analysis. There was a significant reduction in diaphragmatic excursion 20 minutes after magnesium sulfate administration. Additionally, this study provides new insight into the dose effect between serum magnesium level and diaphragmatic excursion characterized by a negative correlation between serum magnesium level and diaphragmatic excursion, demonstrating that increased serum magnesium level is associated with increased diaphragmatic weakness.