Fluid & Electrolytes

What are crystalloids?

IV replacement fluids that maintain the concentration gradient of fluids and electrolytes

What are the 3 types of crystalloids?

Isotonic

Hypotonic

Hypertonic

Hypotonic solution

The solution has a lower solute concentration than inside the cell or blood

Hypertonic solution

The solution has a higher solute concentration than inside the cell or blood

Isotonic solution

The solution has an equal solute concentration to the inside of the cell or blood

What do crystalloids use as a reference point?

The solute concentration of the blood

Name isotonic crystalloids

0.9% Sodium Chloride AKA Normal Saline

Lactated Ringers

Dextrose 5% in water

Name hypotonic crystalloids

0.45% Normal Saline AKA Half NS

Causes cells to BURST, fluids rush INTO the cell

WATCH Na LEVELS! Hypotonic solutions can DECREASE this lab value

Used in patient with HYPERNATREMIA

Name hypertonic crystalloids

3% Normal Saline

5% Normal Saline

Dextrose 10% in water

Causes cells to SHRINK, fluids rush OUT of the cell

WATCH Na LEVELS! Hypertonic solutions can INCREASE this lab value

Used in patient with HYPONATREMIA

Patients are usually placed on a fluid restriction on this medication

S/E: Osmotic Demyelination Syndrome

• caused by a rapid correction of sodium levels (low → high)

• characterized by brain damage or herniation

What are colloids?

Plasma volume expanders that pull fluid from extravascular tissues → intravascular space

There are natural and artificial colloids

Colloids are NOT continuous as they remain in the blood much longer

Due to its concentration of large molecules, colloids cannot easily cross membranes

S/E: fluid volume overload (asses the lungs and for edema)

Natural colloid

Albumin

a blood product that must be wasted as such

Normal Ca level

8.8-10.4

Normal Vitamin D level

20-50

Normal Phosphorus level

2.7-4.5

What is unique about Dextrose 5% & 10% in water?

It CANNOT be administered to diabetics because dextrose is a SUGAR

This will increase the patients blood glucose levels significantly

What is unique about administering saline with packed RBCs?

ONLY 0.9% NORMAL SALINE can be administered/hung with packed RBCs

What continuous IV isotonic solution(s) can you recommend to a patient with normal sodium levels?
Note: Used for hydration purposes

0.9% Normal Saline OR Lactated Ringers

It doesn’t matter in this case! It is based on availability or the healthcare provider

What drugs is NS NOT compatible with?

amphotericin B (severe antifungal)

diazepam (benzodiazepine, a CNS depressant to calm a patient down)

REASON: the drug will precipitate (form solid particles) when mixed with NS

Artificial colloid

hetastarch (Hespan)

Potassium (K) supplementation/replacement

potassium chloride

S/E: GI symptoms and arrhythmias due to hyperkalemia

WATCH K LEVELS (may increase during supplementation)

Magnesium (Mg) supplementation/replacement

magnesium oxide, ORAL

S/E: hypermagnesemia (high Mg in serum blood)

magnesium sulfate, IV

S/E: hypermagnesemia

May be administered IM, but RARE

Calcium (Ca) supplementation/replacement

calcium bicarbonate (Os-cal or Tums)

S/E: constipation & watch vitamin D levels

Phosphorus (Phos) supplementation/replacement

potassium phosphate (K-Phos neutral) ORAL

potassium phosphate (K-Phos) IV

S/E: diarrhea, watch Phos and K levels

sodium phosphate

S/E: diarrhea and watch Phos levels

Can you crush oral potassium replacements?

NO, call the pharmacist to order K powder

Crushing potassium pills can release the drug all at once for dangerous absorption

Potassium replacement equation

Every 10 mEq of potassium increases serum potassium +0.1 mEq

Normal potassium level

3.5-5.2

Normal sodium level

136-145

Normal magnesium level

1.8-2.6

Your patient has a potassium level of 3.2, how much supplementation would you recommend?

30 mEq

over 3 hours IV or one dose oral

How much potassium can you administer via IV at once?

10mEq per hour H

How much potassium can you administer via oral route at once?

40mEq at one time

Can you supplement potassium via IV and oral routes at the same time?

Yes! As long as you maintain IV and oral perimeters and it makes sense for the patient’s potassium goals

Why is potassium so important & so closely monitored?

Potassium maintains HEART and MUSCLE contraction

Arrythmias WILL occur of K is too low/high

S/S of HYPOkalemia

Lethargy

Leg cramps

Cardiac arrhythmias

S/S of HYPERkalemia

Chest pain or rhythm changes

Weakness

Hyperactive bowel sounds or diarrhea

Define extravasation

the accidental leakage of an IV from a blood vessel to surrounding tissue

What do you do when you see S/S of extravasation?

STOP THE INFUSION!
Watch for edema and complaints of burning/pain by the patient

How is potassium often administered?

Via central line because it often causes a burning sensation in peripheral locations due to small vein size

Calcium supplementation patient education

THINK: constipation prevention

Drink lots of fluid to loosen stools

Walk to ensure gastric motility

Eat fiber to prevent constipation