Hypernatremia

Exam 1

hypernatremia

serum sodium above 145mEq/L

hypernatremia

always associated with hypertonicity and due to water loss not adequately replaced or excess sodium

hypovolemic hypernatremia

most common form of hypernatremia

renal losses and extrarenal losses

hypovolemic hypernatremia is due to

loop diuretics, osmotic diuresis, and intrinsic renal disease

renal losses causing hypovolemic hypernatremia caused by

GI losses or cutaneous losses (burns/sweating)

extrarenal losses causing hypovolemic hypernatremia caused by

euvolemic hypernatremia

pure water loss exceeding sodium loss (more sodium than water in body)

diabetes insipidus and increased insensible losses

cause of euvolemic hypernatremia

hypervolemic hypernatremia

excess sodium added to ECF

causes of hypervolemic hypernatremia

• hypertonic saline

• sodium bicarbonate infusion

• TPN

• hypertonic tube feeding

• hypertonic dialysis

• ingestion of sea water

• cushings syndrome

10-12 mEq/L/day

when treating hypernatremia do not correct faster than

start with normal saline to restore intravascular volume then switch to hypotonic fluids once vitals are stable

hypovolemic hypernatremia with unstable vitals (hypotension, tachycardia) treatment

hypontic fluids (D5W, 0.45% NaCl, 0.2%NaCl)

once stable vitals reached in hypovolemic hypernatremia start

1-2mEq/L/hr

if acute hypovolemic hypernatremia correct at a rate of

slow correction to avoid cerebral edema

if treating chronic hypovolemic hypernatremia treat with a

cerebral edema

overcorrecting hypernatremia to quickly may cause

replace free water (D5W) and treat underlying causes

to correct euvolemic hypernatremia

0.5mEq/L/hr with a max of 10-12mEq/L/day

when treating euvolemic hypernatremia correct at a rate of

free water + loop diuretic

to treat hypervolemic hypernatremia use

isotonic saline (0.9% NaCl)

• used when hemodynamically unstable

• to restore intravascular volume

• not for sodium correction alone

• when treating hypernatremia

hypotonic fluids

• in hypernatremia

• used once volume status is stable

• D5W, 0.45% NaCl, 0.2%NaCl

• have to use slower sodium correction

serum sodium and avoid correction over 10-12mEq/L/day

monitoring for giving fluids in hypernatremia

cerebral edema, irreversible neurologic damage, seizure, coma, death

risks of correcting hypernatremia too quickly