Plasma magnesium

The nurse observes the patient for early signs of hypermagnesemia (see Display 58-2) and contacts the primary health care provider immediately if this imbalance is suspected. Frequent plasma magnesium levels are usually ordered. The nurse notifies the primary health care provider if the magnesium level is higher or lower than the normal range... 

As plasma magnesium levels rise above 4 mEq/L, the deep tendon reflexesare first decreased and then absent as the plasma levels reach 10 mEq/L The knee jerk reflex is tested before each dose of magnesum sulfate. If the reflex isabsent ora slow response is obtained, the nurse withholds the dosage and notifies the primary health care provider. 

Haemolysis of the sample will cause a significant increase in plasma magnesium level. Lanthanum is added to samples and standard for convenience so that calcium and magnesium determinations may be made on each sample. 

Corley K T T, Marr C M 1998 Pathophysiology, assessment and treatment of acid-base disturbances in the horse. Equine Veterinary Education 10 255-265 Costa L R R, Eades S E, Tulley R T et al 1999 Plasma magnesium concentrations in horses with gastrointestinal tract disease. Journal of Veterinary Internal Medicine 13 274... 

Barbour HM, Davidson W. Studies on measurement of plasma magnesium application of magon dye method to the Monarch centrifugal analyzer. Clin Chem 1988 34 2103-5. 

Wilhite TR, Smith CH, Landt M. Interference of zinc heparin anticoagulant in determination of plasma magnesium. Clin Chem 1994 40 848-9. 

Plasma contains 1.6-2.3 mg/dL (0.7-1.0 mmol/L) of magnesium, 20-25% of which is protein bound. As with Ca +, the unbound (ionized) portion of plasma magnesium is the biologically active fraction. Intracellular Mg + concentration is about 10 mmol/L, mostly bound to organelles. The intracellular concentration of free Mg " " is 0.025-0.5 mmol/L. 

Little or no change has been observed in the plasma magnesium con-... 

The normal range of plasma magnesium concentration is 0.75 to 1 mmol (Wei-singer and Bellorin-Font 1998). If homeo-... 

Hirscheelder ad and Haury VG (1934) Clinical manifestations of high and low plasma magnesium dangers of Epsom salt purgation in nephritis. J Am Med Assoc 102 1138-1141. 

Loss by diarrhea is probably largely responsible for the low plasma potassium often ol rved in PEM values less than 2.S mmol/l have been recorded. Plasma magnesium may be low for the same reason. Plasma sodium is usually normal. Total body water increases to 65-80 % of body weight (60 % is normal). 

Magnesium very probably plays an important role in both diseases. With the normal civilized food products and dietary habits, the daily intake of magneaum is too low (Keeser, 1952). With increasing age the tissue content of magnemum decreases, whereas the calcium content increases. If the plasma magnesium level decreases from 2.2 mg. % to 1... 

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