Hypomagnesemia is commonly seen but frequently overlooked in critically ill patients in intensive care unit (ICU). However, the strength and consistency of the effect of hypomagnesemia on outcomes in critically ill patients remain controversial. In this report, we performed a systematic review and meta-analysis to evaluate the association of serum magnesium level with prognosis of critically ill patients upon admission to the ICU. A comprehensive search for clinical trials was performed, and 10 studies comprising 1,122 cases and 630 controls were finally selected for analysis. The patients with hypomagnesemia had higher mortality rate (risk ratio [RR] 1.76; 95% confidence interval [CI] 1.54-2.00; P <0.00001), more frequently had sepsis (RR 2.04; 95% CI 1.21-3.42; P = 0.0007) and more frequent need for ventilatory support (RR 1.36; 95% CI 1.21 to 1.53; P <0.00001). Length of ICU stay was also higher in the hypomagnesemia group (RR 1.85; 95% CI 0.43- 3.26; P = 0.01). Collectively, our data indicated that hypomagnesemia appears associated with greater risk of mortality, sepsis, mechanical ventilation, and the length of ICU stay in patients admitted to ICU. The role of magnesium therapy for improving outcomes in critically ill patients is needed to further study.

PurposeChoosing the appropriate time to switch to noninvasive positive-pressure ventilation (NPPV) plays a crucial role in promoting successful weaning. However, optimal timing for transitioning and weaning patients from mechanical ventilation (MV) to NPPV has not been clearly established. In China, the pulmonary infection control (PIC) window as a switching point for weaning from MV has been performed for many years, without definitive evidence of clinical benefit. This study aimed to summarize the evidence for NPPV at the PIC window for patients with respiratory failure from COPD.MethodsA comprehensive search for randomized controlled trials (RCTs) was performed. The trials were all parallel studies comparing the PIC window weaning strategy versus conventional weaning strategy in treatment of patients with respiratory failure due to COPD.ResultsSixteen studies of 647 participants were eligible. When compared with conventional weaning strategy, early extubation followed by NPPV at the point of PIC window significantly reduced the mortality rate (risk ratios [RRs] 0.36, 95% confidence interval [CI] 0.23 to 0.57) and ventilator-associated pneumonia (VAP) (RR 0.28, 95% CI 0.19 to 0.41); it also decreased the duration of invasive ventilation (weighted mean difference [WMD] −7.68 days, 95% CI −9.43 to −5.93) and total duration of ventilation (WMD −5.93 days, 95% CI −7.29 to −4.58), which also shortened the lengths of stay in an intensive care unit (WMD −8.51 days, 95% CI −10.23 to −6.79), as well as length of stay in hospital (WMD −8.47 days, 95% CI −8.61 to −7.33).ConclusionThe results showed that the PIC window as a switching point for sequential ventilation in treatment of respiratory failure in COPD patients may be beneficial. It might yield not only relevant information for caregivers in China but also new insights for considering the PIC window by physicians in other countries.