Chen Minhua, Sun Renhua, Hu Bangchuan
Department of Critical Care Medicine, Zhejiang Provincial People's Hospital, Hangzhou 310014, Zhejiang, China. Corresponding author: Sun Renhua, Email:
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2015 Mar;27(3):213-7. doi: 10.3760/cma.j.issn.2095-4352.2015.03.011.
To investigate the incidence of hypomagnesemia and the effect of serum magnesium levels on the prognosis of critically ill patients in intensive care unit (ICU).
A single-center prospective observation was conducted. The adult patients admitted to ICU of Zhejiang Provincial People's Hospital from January 2012 to January 2014 were enrolled, and they were expected to stay in hospital for more than 48 hours. All the patients who had been diagnosed with hypomagnesemia before ICU admission, or those who had received magnesium supplement therapy were excluded. All patients were monitored for serum magnesium levels within 24 hours after ICU admission, and they were divided into three groups: normomagnesemic group (serum magnesium levels 0.7-1.2 mmol/L), hypomagnesemic group (serum magnesium levels < 0.7 mmol/L), and hypermagnesemic group (serum magnesium levels > 1.2 mmol/L). Various parameters were recorded for every patient, including general information, disease composition, laboratory indexes, duration of mechanical ventilation, ICU stay days and final outcome. The acute physiology and chronic health evaluation II (APACHEII) score and sequential organ failure assessment (SOFA) score during the first 24 hours after ICU admission were calculated. The risk factors for the death in critically ill patients were postulated by logistic regression analysis.
A total of 374 critically ill patients were enrolled, with 242 patients (64.71%) in normomagnesemic group, 102 (27.27%) in hypomagnesemic group, and 30 (8.02%) in hypermagnesemic group. As to the disease composition, although the patients in normomagnesemic group and hypomagnesemic group were mainly consisted of patients with nervous system diseases (33.06%, 31.37%) or pneumonia (25.62%, 25.49%), the proportion of patients with major abdominal and thoracic surgery (15.69% vs. 5.78%, χ (2) = 8.837, P = 0.003) or severe sepsis (7.84% vs. 1.65%, χ (2) = 9.935, P = 0.007) was significantly greater in the hypomagnesemic group compared with that of normomagnesemic group, and most hypermagnesemic patients were complicated by renal dysfunction in different degrees. Compared with the normomagnesemic group, the hypomagnesemic group was found to have higher SOFA scores (6.86±3.12 vs. 5.46±2.75, t = -2.930, P = 0.004), longer stay in ICU (days: 15.98±13.29 vs. 12.43±7.14, t = -2.318, P = 0.034) and higher mortality [54.90% (56/102) vs. 33.88% (82/242), χ (2) = 6.587, P = 0.010], but no statistically significant differences were found in gender composition, age, levels of other electrolytes (natrium, potassium, calcium, phosphorus), and APACHEII score. As shown by the result of the logistic regression analysis, APACHEII score [odds ratio (OR) = 1.129, 95% confidence interval (95%CI) = 1.064-1.197, P = 0.000] and serum magnesium level (OR = 2.163, 95%CI = 1.015-4.610, P = 0.046) were independent risk factors for death in critically ill patients.
Serum magnesium levels are closely related to mortality rate in patients in ICU, so more attention should be paid to the occurrence of hypomagnesemia in critically ill patients.
探讨重症监护病房（ICU）中低镁血症的发生率以及血清镁水平对危重症患者预后的影响。
进行单中心前瞻性观察。纳入2012年1月至2014年1月入住浙江省人民医院ICU的成年患者，预计住院时间超过48小时。排除所有在ICU入院前已诊断为低镁血症或已接受镁补充治疗的患者。所有患者在ICU入院后24小时内监测血清镁水平，并分为三组：正常镁血症组（血清镁水平0.7 - 1.2 mmol/L）、低镁血症组（血清镁水平<0.7 mmol/L）和高镁血症组（血清镁水平>1.2 mmol/L）。记录每位患者的各种参数，包括一般信息、疾病构成、实验室指标、机械通气时间、ICU住院天数及最终结局。计算ICU入院后前24小时的急性生理与慢性健康状况评分II（APACHEII）和序贯器官衰竭评估（SOFA）评分。通过逻辑回归分析推测危重症患者死亡的危险因素。
共纳入374例危重症患者，正常镁血症组242例（64.71%），低镁血症组102例（27.27%），高镁血症组30例（8.02%）。就疾病构成而言，尽管正常镁血症组和低镁血症组患者主要为神经系统疾病（33.06%，31.37%）或肺炎（25.62%，25.49%）患者，但低镁血症组中接受重大腹部和胸部手术的患者比例（15.69%对5.78%，χ² = 8.837，P = 0.003）或严重脓毒症患者比例（7.84%对1.65%，χ² = 9.935，P = 0.007）显著高于正常镁血症组，且大多数高镁血症患者合并不同程度的肾功能不全。与正常镁血症组相比，低镁血症组SOFA评分更高（6.86±3.12对5.46±2.75，t = -2.930，P = 0.004），ICU住院时间更长（天数：15.98±13.29对12.43±7.14，t = -2.318，P = 0.034），死亡率更高[54.90%（56/102）对33.88%（82/242），χ² = 6.587，P = 0.010]，但在性别构成、年龄、其他电解质（钠、钾、钙、磷）水平及APACHEII评分方面未发现统计学显著差异。逻辑回归分析结果显示，APACHEII评分[比值比（OR） = 1.129，95%置信区间（95%CI） = 1.064 - 1.197，P = 0.000]和血清镁水平（OR = 2.163，95%CI = 1.015 - 4.610, P = 0.046）是危重症患者死亡的独立危险因素。
血清镁水平与ICU患者死亡率密切相关，因此应更加关注危重症患者低镁血症的发生。
