UAG


gap

(gap) [Old Norse gap, chasm] 1. An opening or a break; an interruption in continuity.2. The difference between the expected and the measured concentration of solute in the plasma.

anion gap

The difference between the measured cations sodium (Na+) and potassium (K+) and the measured anions chloride (Cl-) and bicarbonate (HCO3-). In accordance with the principle of electroneutrality, in any body fluid the number of net positive charges contributed by cations must equal the number of net negative charges contributed by anions. The unmeasured anions include lactate, sulfates, phosphates, proteins, ketones, and other organic acids. In general an anion gap of 10 to 14 mmol/L is normal. An increased value is present in metabolic acidosis.

auscultatory gap

A period of silence that sometimes occurs in the determination of blood pressure by auscultation. It may occur in patients with hypertension or aortic stenosis. See: blood pressure; pulsus paradoxus

evidence-practice gap

The failure of clinicians to adopt proven practices that enhance outcomes for patients. The disparity between usual professional practice and evidenced-based guidelines.

health care gap

A disparity between health care needs and health care services, esp. as it applies to the medically indigent.

osmolal gap

The difference between the measured osmolality of the plasma, and the calculated osmolality of the plasma (plasma glucose/18 + blood urea nitrogen/2.8 + sodium*2). A gap is present when the difference exceeds 10 mmol/kg of water. Osmolal gaps are present when unmeasured osmotically active solutes, such as toxins, e.g., methanol or ethylene glycol, are present in the plasma.

urine anion gap

Abbreviation: UAG
The sum of the concentrations of sodium and potassium in a specimen of urine, minus the urine chloride concentration. The UAG is used to assess the source of a metabolic acidosis. A positive value indicates the kidney is responsible for the acidosis. A large negative value indicates the kidneys are compensating for a metabolic acidosis caused by other organs.

urine anion gap

Abbreviation: UAG
The sum of the concentrations of sodium and potassium in a specimen of urine, minus the urine chloride concentration. The UAG is used to assess the source of a metabolic acidosis. A positive value indicates the kidney is responsible for the acidosis. A large negative value indicates the kidneys are compensating for a metabolic acidosis caused by other organs. See also: gap