ammonium(redirected from ammonium ion)
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a hypothetical radical, NH4, forming salts analogous to those of the alkaline metals.
ammonium carbonate a mixture of ammonium compounds used as a liquefying expectorant in the treatment of chronic bronchitis and similar lung disorders. It is sometimes used as a reflex stimulant in “smelling salts” because of the strong ammonia odor it gives off.
ammonium chloride colorless or white crystals, with a cool, salty taste, used as an expectorant because it liquefies bronchial secretions. In the body it is changed to urea and hydrochloric acid, and thus is useful in acidifying the urine and increasing the rate of urine flow. Excessive dosage may produce acidosis.
ammonium lactate lactic acid neutralized with ammonium hydroxide, applied topically in the treatment of ichthyosis vulgaris and xerosis.
An ion, NH4+, formed by combining NH3 and H+ (the pKa value is 9.24); acts as a univalent metal in forming ammonium compounds.
storage lesionTransfusion medicine The constellation of changes occurring in a unit of packed red cells during storage. See Red cell preservatives.
↑ Ammonium to 470 µmol/L–US: 800 µg/dL
↑ Free Hb in plasma from 82 to 6580 mg/L–US: 8.2 to 658 mg/dL
↑ K+ from 4.2 to 78.5 mmol/L–US: 4.2 to 78.5 mEq/L
↓ ATP from 100% to 45%
↓ 2,3 DPG to < 10% of original levels–replenished within 24 hours of transfusion
↓ Labile proteins, eg complement, fibronectin and coagulation factors ↓ to negligible
↓ Na+ from 169 to 111 mmol/L–US: 169 to 111 mEq/L
↓ pH from 7.6 to 6.7
Adverse physiologic effects of stored blood is negligible in the absence of a previous compromise of the Pt's–recipient's status
The ion, NH4+, formed by combination of NH3 and H+; behaves as a univalent metal in forming compounds.