Phosphate

Question 1

Phosphate

Answer 1

Primary intracellar anion, 65% in bones, 14% in intracellular, 1% extracellular
Essential for production of ATP (helps nerve/muscle contraction as well as electrolyte transport)

Vital for red blood cell function, O2 delivery, metabolism of fats, carbohydrates and proteins, helps maintain acid base balance

Absorbed in the jejunum and excreted by kidneys (kidneys keep phosphate when blood levels are low)

Phosphate will be high and calcium will be low in renal failure as kidneys unable to excrete it

If calcium rises phosphate falls and vice versa

Question 2

Hypophosphataemia

Answer 2

Shift of phosphate into intracellular, decreases intake, decreases absorption in GI and increased renal excretion

Refeeding syndrome (malnourished person starts on TPN, glucose in formula stimulates insulin release which promotes entry of glucose and phosphate into cells

Medications- IV glucose, antacids, steroids and diuretics

Alcoholism

hyperventilation and resp alkalosis cause phosphate to move into cells

Diabetic ketoacidosis (excess phosphate lost in urine), stress, burns

S&S-
CNS-reduced O2 and ATP synthesis leads to irritability, apprehension, weakness, lack of co-ordination, seizures
Haematological- reduced O2 to cells, haemolytic anaemia due to lack of ATP
Muscle- weakness/pain, parasthesia, release of creatinine phosphate, acute rhabdomyolysis
Resp- chest muscle weakness interfering with adequate ventilation
Cardio- decreases myocardial contractility, chest pain due to reduced O2, arrhythmias
GI- anorexia, dysphagia, nausea/vomiting, decreases bowel sounds, ileus

Question 3

Hyperphosphatemia

Answer 3

Excess intake, impaired excretion, shift from intracellular to extracellular

Renal failure, excess Vit D can increase absorption, solutions containing phosphate, shift from intracellular caused by chemo/ sepsis/hypothermia/ trauma/ heat stroke

S&S- muscle spasm, tetany, soft tissue calcification