Limaye C S, Londhey V A, Nadkart M Y, Borges N E
Department of Medicine, TN Medical College and BYL Nair Ch. Hospital, Mumbai 400 008.
J Assoc Physicians India. 2011 Jan;59:19-22.
Hypomagnesemia is an important but underdiagnosed electrolyte abnormality in critically ill patients. There are many studies to find the prevalence of hypomagnesemia and its effects on mortality and morbidity in these patients. Most of these studies have been carried out in intensive care units caring for patients with medical and surgical conditions and postoperative patients or those in respiratory intensive care unit, or critically ill cancer patients. This study was carried out on patients admitted to the medical acute care unit in a major tertiary care hospital.
To study serum magnesium levels in critically ill patients and to correlate serum magnesium levels with patient outcome considering the following parameters: length of stay in MICU, need for ventilatory support, duration of ventilatory support, APACHE score and mortality. To identify the primary medical conditions associated with abnormalities of serum magnesium. To identify the factors predisposing or contributing to hypomagnesemia in critically ill patients admitted in a medical intensive care unit. To detect other electrolyte abnormalities associated with hypomagnesemia, if any.
On admission to MICU 52% patients had hypomagnesemia, 7% patients had hypermagnesemia and 41% patients had normomagnesemia. The patients with hypomagnesemia had higher mortality rate (57.7% vs 31.7%), more frequent need for ventilatory support (73% vs 53%), longer duration of mechanical ventilation (4.27 vs 2.15 days), more frequently had sepsis (38% vs 19%), hypocalcemia (69% vs 50%) and hypoalbuminemia (80.76% vs 70.8%). Patients with diabetes mellitus had hypomagnesemia more frequently (27% vs 14%). The duration of stay in the MICU or APACHE score on admission did not vary in patients with low or normal magnesium.
There was a high prevalence of hypomagnesemia in the critically ill patients. Hypomagnesemia was associated with a higher mortality rate in critically ill patients. The need for ventilatory support was significantly higher in hypomagnesemic patients. Hypomagnesemic patients required ventilator support for longer duration. Hypomagnesemia was commonly associated with sepsis and diabetes mellitus. The duration of MICU stay and APACHE score on admission did not vary in patients with low magnesium and normal magnesium. Hypomagnesemia is more commonly seen in patients with hypocalcemia and hypoalbuminemia.
低镁血症是危重症患者中一种重要但未得到充分诊断的电解质异常情况。有许多研究致力于探寻低镁血症的患病率及其对这些患者死亡率和发病率的影响。这些研究大多是在收治内科和外科疾病患者、术后患者或呼吸重症监护病房患者的重症监护病房，或是危重症癌症患者中开展的。本研究针对一家大型三级护理医院内科急性护理病房收治的患者进行。
研究危重症患者的血清镁水平，并将血清镁水平与患者的预后进行关联分析，考虑以下参数：在重症监护病房（MICU）的住院时长、通气支持需求、通气支持持续时间、急性生理与慢性健康状况评分系统（APACHE）评分及死亡率。确定与血清镁异常相关的主要内科疾病。确定入住内科重症监护病房的危重症患者发生低镁血症的易感因素或促成因素。检测与低镁血症相关的其他电解质异常情况（如有）。
入住MICU时，52%的患者存在低镁血症，7%的患者存在高镁血症，41%的患者镁水平正常。低镁血症患者的死亡率更高（57.7%对31.7%），通气支持需求更频繁（73%对53%），机械通气持续时间更长（4.27天对2.15天），脓毒症（38%对19%）、低钙血症（69%对50%）和低白蛋白血症（80.76%对70.8%）更为常见。糖尿病患者发生低镁血症的频率更高（27%对14%）。镁水平低或正常的患者在MICU的住院时长或入院时的APACHE评分并无差异。
危重症患者中低镁血症的患病率很高。低镁血症与危重症患者较高的死亡率相关。低镁血症患者通气支持需求显著更高。低镁血症患者需要更长时间的通气支持。低镁血症通常与脓毒症和糖尿病相关。镁水平低和正常的患者在MICU的住院时长及入院时的APACHE评分并无差异。低镁血症在低钙血症和低白蛋白血症患者中更为常见。
