DFM Fellows Summer 2010. Objectives Understand the basics of fluid administration Review basics of various fluid options Be able to calculate maintenance.

IV Fluid ManagementDFM Fellows

Summer 2010

ObjectivesUnderstand the basics of fluid

administrationReview basics of various fluid optionsBe able to calculate maintenance fluid

rates based on patient weightBe able to estimate fluid losses Be able to calculate fluid replacement

The Learning CurveThe information provided is general

information regarding fluid administration. Keep in mind that different clinical situations require you to integrate your clinical knowledge of the body and its physiology to make an educated decision. Always consider the patients age, condition, medications and co morbidities before administering fluids.

And as you screw up you will learn!

IV Fluids The role of IV fluid administration is to

Provide volume replacement Administer medications, electrolytes, blood

products, or diagnostic reagents Maintenance/correction of nutritional status

Components of fluid and electrolyte therapy1. Maintenance2. Replacement

Normal Plasma Electrolyte CompositionCATION Concentrati

on mEq/LANION Concentrati

on mEq/L

Sodium 135-145 Chloride 95-105

Potassium 3.5-5.0 Phosphate

2.5-30

Calcium 4.0-5.5 Sulfate 1.0

Magnesium

1.5-2.5 Organic acids

2.0

Osmolarity

285-295 Protein 1.6

Commonly Used IV SolutionsOsmolarity (mOsm/L)

Glucose(gm/L)

Na+ (mEq/L)

K+(mEq/L)

Cl- (mEq/L)

Lactate (mEq/L)

Ca++ (mEq/L)

0.9%NS

308 154 154

½ NS (.45%NS)

154 77 77

LR 274 130 4.0 109 28 3

D5W 278 50

D5 ½ NS

406 50 77 77

Components of Fluid and Electrolyte Therapy1. Maintenance

• meeting the requirements for fluid and electrolyte intake that balance daily obligatory losses

2. Replacements (Ongoing Losses)• providing for ongoing and additional losses

that occur during the course of therapy (surgery phases: pre/intra/post operative)

The Balancing ActIN

Drinking Eating Metabolism

3mL/kg IV Fluids?

OUT (~1-1.6L/day for ave. adult) Urine

12-15mL/kg/day Feces

3mL/kg Insensible losses

10-13mL/kg/day

With no unusual stresses or losses and normal renal function intake can be balanced to outputs

Maintenance: Water and Electrolyte NeedsReplace Urine and insensible losses (1-2

L/day)Replace sodium and potassium loss

Na: need 47-147 mEq/day (1-3mEq/kg/day)K: leak about 20mEq/dayOsmol

arity (mOsm/L)

Glucose(gm/L)

Na+ (mEq/L)

K+(mEq/L)

Cl- (mEq/L)

Lactate (mEq/L)

Ca++ (mEq/L)

0.9%NS

308 154 154

½ NS (.45%NS)

154 77 77

Calculating Maintenance Dosing4-2-1 rule to

calculate hourly rateIn one hour, a

person needs:4mL/kg for the first

10kg (0-10)2mL/kg for the next

10kg (10-20)1mL/kg for the

remaining kg (>20)

100-50-20 rule for daily requirements

In one day a person needs:100 mL/kg for the

first 10kg50 mL/kg for the

second 10kg20 mL/kg for the

remaining*Remember to divide by

24 for hourly rate*

Maintenance ConsiderationsFever or high ambient temperatures

Water loss increases by 100-150ml/day for every degree above 37C

SweatingConsider using a hypotonic solution for fluid

replacement (0.45% saline)Humidity

Breathing humid air decreases loss while dry air may increase relative losses

ExampleCalculate maintenance fluids for a 75 kg patient

who is NPO

4-2-1 Rule10 x 4 = 40 mL10 x 2 = 20 mL55 x 1 = 55 mL

Total 115 mL/hr

100-50-20 Rule10 x 100 = 1000mL10 x 20 = 200 mL55 x 20 = 1100

Sub total 2300mL/day

Total 96 mL/hr

So you know how to calculate fluid maintenance requirements but what happens if the patient has an initial deficit requiring rehydration other than maintenance?

Think About It

What are you concerned about?

DehydrationElectrolyte imbalanceDecrease in blood pressure

What do you want to do?

Administer medication for nausea

Normalize ElectrolytesExpand her intravascular

volume Maintain normal fluid

homeostasis (maintenance) Replace lost fluid

(resuscitation) Account for ongoing losses if

present (replacement)

A 50 kg patient comes into the ED with gastroenteritis

She has had vomiting and has diarrhea x 3days

Clinical Signs of DehydrationFeature Mild

dehydration (<5%)

Moderate dehydration(5%-10%)

Severe dehydration (>10%)

Heart Rate

Normal Slight increase

Rapid, weak

Systolic BP

Normal Normal/ orthostatic

Hypotension

Mucous Mb

Slightly dry

Very dry Parched

Urine Output

Decreased

Olguria < 500ml/day

Anuria < 50ml/day

Clinical Signs of DehydrationThis is an objective finding

This is a rough estimate of fluid lossClinical signs may not be evident in adults

Adults are able to compensate better than children

CalculationFluid Deficits(L) = weight (kg) x % dehydration

Example: Our 50 kg patient with 5% dehydration:50kg x 5%= 2.5L deficit

Estimate Deficit by Weight

Fluid and Weight1 L of fluid = 1 kg of

weight1kg= 2.2 lbs

Use weight change to determine fluid loss/gain

Calculate his fluid deficit

5lb = 2.3kg == 2.3L fluid deficit

Example: Suppose our gastroenteritis patient reports a 5lb weight loss with illness

Fluid DeficitsAfter deficit is determined

Our pt has a 2.3L deficit by weight

Replace half in 8 hours1,150mL/8hrs =143mL/hr for the first 8 hrs

Replace other half in the next 16 hours1150mL/16hrs=72mL/hr for the next 16hrs

Total Flow Rate for Maintenance

Maintenance4mL/kg x 10kg = 40mL (0-10) plus2mL/kg x 10kg

= 20mL (10-20) plus

1cc/kg x 30kg= 30mL (20-50)

TOTAL maintenance= 90mL/hr

Deficit1,150mL/8hrs=143mL/hr

for the first 8 hrs

1150mL/16hrs=72mL/hr for the next 16hrs

• Add maintenance to deficit and you’ll have a flow rate• Our 50kg patient with gastroenteritis has had a 5lb (2.3kg)

weight loss

Total Flow RateFor the first 8 hrs

90mL/hr + 143mL/hr = 233mL/hr

For the next 16 hours90mL/hr + 72mL/hr = 162mL/hr

Try it!A 176lb athlete presents to the ER after

collapsing during football practice. He weighed 184lbs at the beginning of practice. Write an order for IV fluids to correct for deficit and maintenance for the next 24 hours

Note: Use patients current weight to determine maintenance

AnswerMaintenance176lb = 80kg40mL (0-10) plus20mL (10-20)

plus60mL (20-80)

Total= 120mL/hr

Deficit184 - 176= 8lb = 3.6kg

=3.6L = 3,600mL loss

1,800mL/ 8 = 225ml/hr• 225 + 120= • 345 mL/ hr for the 1st 8

hrs 1,800/16 = 112.5mL/hr

• 112.5 + 120 =• 232.5 mL/ hr for the next

16 hrs