|
Hypermagnesemia is an electrolyte disturbance in which there is an abnormally elevated level of magnesium in the blood. Usually this results in excess of magnesium in the body. Hypermagnesemia occurs rarely because the kidney is very effective in excreting excess magnesium. It usually develops only in people with kidney failure who are given magnesium salts or who take drugs that contain magnesium (e.g. some antacids and laxatives). It is usually concurrent with other electrolyte disturbances such as a low blood calcium and/or high blood potassium level. ==Signs and symptoms== * Weakness, nausea and vomiting * Impaired breathing * Decreased respirations * Low blood pressure * Low blood calcium * Abnormal heart rhythms and Asystole * Decreased or absent deep tendon reflexes * Low heart rate *Dizziness *Sleepiness Abnormal heart rhythms and asystole are possible complications of hypermagnesemia related to the heart. Magnesium acts as a physiologic calcium blocker, which results in electrical conduction abnormalities within the heart. Clinical consequences related to serum concentration: *4.0 mEq/l hyporeflexia *>5.0 mEq/l Prolonged atrioventricular conduction *>10.0 mEq/l Complete heart block *>13.0 mEq/l Cardiac arrest Note that the therapeutic range for the prevention of the pre-eclampsic uterine contractions is: 4.0-7.0 mEq/L.〔Pritchard JA. The use of the magnesium ion in the management of eclamptogenic toxemias. Surg Gynecol Obstet. 1955; 100:131–140〕 As per Lu and Nightingale,〔Lu JF,Nightingale CH. Magnesium sulfate in eclampsia and pre-eclampsia. Clin Pharmacokinet. 2000; 38:305–314〕 serum Mg2+ concentrations associated with maternal toxicity (also neonate depression - hypotonia and low Apgar scores) are: * 7.0-10.0 mEq/L - loss of patellar reflex * 10.0-13.0 mEq/L - respiratory depression * 15.0-25.0 mEq/L - altered atrioventricular conduction and (further) complete heart block * >25.0 mEq/L - cardiac arrest 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hypermagnesemia」の詳細全文を読む スポンサード リンク
|