iv fluids. basic principles basic principles 1. osmolality/osmolarity 2. tonicity 3. sodium &...

IV FLUIDS

Basic Principles

BASIC PRINCIPLES

1. Osmolality/Osmolarity

2. Tonicity

3. Sodium & Water balance

What is Osmolality

?

OSMOLALITY

Measurement of concentration of particles in a solution

(Total concentration of penetrating & nonpenetrating solutes)

i.e. Concentration of electrolytes, drugs, glucose in a solution such as serum or urine

OSMOLALITY

Normal = 285-295 mOsm/kg

The ICF and ECF are in osmotic equilibrium

OSMOLALITY

OSMOLALITY = mOsm/kg of solvent

OSMOLARITY = mOsm/liter of a solution

What is Tonicity?

TONICITY

measure of the ability of a solution to cause a change in the volume or tone of a cell by promoting osmotic flow of water

(Total concentration of penetrating solutes only)

TONICITY

Who regulates osmolality?

Water

WATER BALANCE

Important in the regulation of osmolality

Modification of water intake and exretion

60%

ICF

ECF

TOTAL BODY WATER

Interstitial Fluid

Plasma

FORCES THAT MOVE WATER

Osmolality

Tonicity

Na/K ATPase pump

Hydrostatic pressure

Oncotic pressure

SODIUM BALANCE

The main regulator of intravascular volume status

Electrolyte composition

EXTRACELLULAR FLUID INTRACELLULAR FLUID

WHAT IS THE BODY’S GOAL?

PHYSIOLOGIC HOMEOSTASIS

EUVOLEMIA

ISOTONIC ENVIRONMENT

What mechanisms in the body makes sure that the balance of sodium and water is normal?

What hormones play a big role in the maintenance of physiologic homeostasis?

There are upper & lower limits to the amount

needed to achieve ideal physiologic homeostasis

WATER REPLACEMENT

1.5 to 2 liters / day

SODIUM REQUIREMENT

DIET: RDA = < 2400mg/day (1 teaspoon/day)

or < 104 meq/day

PLASMA : Normal levels = 135-145meq/L

FOR Na CORRECTION: Maintenance of 2-4 meq/kg/day

Intravenous Fluids

INTRAVENOUS FLUIDS

chemically prepared solutions

Achieve and maintain a euvolemic and isotonic environment within the body

They are tailored to the body’s needs and used to replace lost fluid and/or aid in the delivery of IV medications

ISOTONIC IV FLUIDS

created to distribute evenly between the intravascular, interstitial, and cellular spaces.

HYPOTONIC IV FLUIDS

What IV fluids are specifically designed so the fluid leaves the intravascular space and enters the interstitial and intracellular spaces?

HYPERTONIC IV FLUIDS

What IV fluids are designed to stay in the intravascular space (intra, within; vascular, blood vessels) to increase the intravascular volume, or volume of circulating blood?

ISOTONIC SOLUTIONS = 285-295 mOsm/L

Na = 135-145meq/L

HYPERTONIC SOLUTIONS = > 300 mOsm/L

Na = > 150meq/L

HYPOTONIC SOLUTIONS = < 260 mOsm/L

Na < 130meq/L

CRYSTALLOIDS

contain electrolytes (e.g., sodium, potassium, calcium, chloride) but lack the large proteins and molecules found in colloids.

classified according to their “tonicity.”

describes the concentration of electrolytes (solutes) dissolved in the water, as compared with that of body plasma (fluid surrounding the cells).

COMPOSITION OF IV FLUIDS

IV FLUID OSMOLARITY(mosm/L)

Na+ (mmol/L)

K+ Cl- Base

PNSS 308 154 0 0 ?

PLR 273 130 ? ? ?

D5LR 525 130 4 109 28

D5NR 552 140 ? 98 50

D50.3NaCl 355 51 0 51 0

D5IMB 350 25 20 22 23

D5NM 368 40 3 40 16

D5W 255 0 0 0 0

COLLOIDS

contain solutes in the form of large proteins or other similarly sized molecules.

Remain in the blood vessels for long periods of time and can significantly increase the intravascular volume (volume of blood).

COLLOIDS/PLASMA EXPANDERS

Albumin = 1-2 kg/dose infused in 2 hours

Haes-teryl = 20-40ml/kg

Voluven = 20-40ml/kg

Gelofuschin = 20-40ml/kg

Fresh frozen plasma = 10-15ml/kg x 4 hours

Dextran 40 or 60

BLOOD AND BLOOD PRODUCTS

are the most desirable fluids for replacement but are not the first choice for immediate volume expansion in children with shock

Not only is the intravascular volume increased, but the fluid administered can also transport oxygen to the cells.

BLOOD AND BLOOD PRODUCTS

BLOOD PRODUCT COMPUTATION

pRBC 10 ml/kg to run for 4 hours

Fresh whole blood 10-20 ml/kg in 4-6 hours

Platelet Concentrate

15-20 ml/kg as fast drip

Cryoprecipitate 1 unit/6kg/dose

Computation

OVERALL GOALS

STEP ONE: Estimate LossesSEVERITY OF DEHYDRATION

INFANT (ml/kg)

ADOLESCENT (ml/kg)

CLINICAL SIGNS

MILD 5% (50) 3% (30) •Dry mucous membranes•Oliguria

MODERATE 10% (100) 6% (60) •Poor skin turgor•Sunken fontanel•Marked oliguria•Tachycardia•Quiet tachypnea

SEVERE 15% (150) 9% (90) •Marked tachycardia•Weak to absent distal pulses•Narrow pulse pressure•Quiet tachypnea•Hypotension and altered mental status

STEP TWO: In shock?

1. MACRODRIP SETS = 10 – 15 drops (gtts)/ml

2. MICRODRIP SETS= 60 microdrops (ugtts)/ml)

(Volume in mL) x (drip set)    gtts

------------------------------------ = ------

(Time in minutes)    min

CONVERSION FACTORS

1 ml = 15 drops (gtts) = 60 microdrops (ugtts)

1 drop (gtt) = 4 microdrops (ugtts)

1 microdrop (ugtts)/min = 1 ml/hour

FLUID DEFICITSLudan’s Method

WEIGHT MILD DEHYDRATIONml/kg/8 hours

MODERATE DEHYDRATION

SEVERE DEHYDRATION

<15 kg 50 100 150

>15 kg 30 60 90

•Give ¼ in 1 hr•Give ¾ in 7 hr

•Give 1/3 in 1 hr•Give 2/3 in 7hr

•PLAIN LR/PLAIN NSS•D5LR

•PLAIN LR/ PLAIN NSS•D5LR

FLUID DEFICITS – WHO*Use Ringer’s Lactate

AGE FIRST GIVE 30ml/kg in:

THEN GIVE70ml/kg in:

Infants under 12 months

1 hour 5 hours

Older 30 minutes 2 ½ hours

SEVERE DEHYDRATION

SOME DEHYDRATION75ml/kg in 4 hours

SODIUM CORRECTION

1. DEFICIT CORRECTION: desired-actual x weight x 0.6 * Desired Na+ is 135-145 meq

2. MAINTENANCE COMPUTATION: maintenance x weight *Maintenance is 2-4meq/kg

3. COMPUTE FOR ACTUAL Na+ Needed to be incorporated in your IV FLUID = Maintence + Deficit

*Give the First ½ in 8 hours then ¼ in each succeeding 8 hour shifts to complete your 24 hour correction

POTASSIUM CORRECTION

1. COMPUTE FOR THE K+ REQUIREMENT = 2-4meq/kg/day

2. DETERMINE how much KCL you will be incorporating in your IV fluid to complete a 24 hour correction

a) Check IV fluid rate

b) *Maximum 40meq/Liter of KCL incorporation in IV Fluid

3. CHECK POTASSIUM INFUSION RATE (KIR) =meq of KCL x IV rate (ml/hour) x weight

(maximum of 0.2meq/kg/hour)

MAINTENANCE REQUIREMENTSHolliday-Segar Method

BODY WEIGHT WATER (ml/kg/day)

First 10 kg 100 ml/kg

Second 10 kg (<20kg) 50ml/kg for each kg > 10kg + 1000ml

Each additional kg (>20kg)

20ml/kg for each kg > 20kg + 1500ml

MAINTENANCE REQUIREMENTSLudan Method

BODY WEIGHT (kg) TOTAL FLUID REQUIREMENT (TFR)

at ml/kg/day

> 3-10 kg 100ml/kg/day

> 10-20 kg 75ml/kg/day

> 20-30 kg 50-60ml/kg/day

>30-60 kg 40-50ml/kg/day

IV FLUID SELECTION

INITIAL REPLACEMENT (GOAL: Restore Intravascular volume & Tissue Perfusion)– always with an ISOTONIC SOLUTION PNSS , PLR, PNR

FOLLOW UP HYDRATION (For Ongoing Losses) – Isotonic/Hypertonic, can be Glucose containing D5LR, D5NR

MAINTENANCE – Usually Hypotonic D5IMB , D5NM

FLUIDS NOT WORKING?

Review medications: Dopamine Dobutamine Norepinephrine Epinephrine Milrinone Vasopressin Nitroprusside

STEP THREE: Frequent Reassessment

Pulse quality

Heart Rate

Capillary Refill Time

Urine Output

Temperature

Blood Pressure

Neurologic Function

Oxygen saturation

Breath sounds and respiratory rate

STEP FOUR: Ancillary studies & Pharmacologic interventions

ANCILLARY STUDIES

Shock etiology & severity

Organ dysfunction

Metabolic derangements

Response to therapeutic interventions

TREATMENT

Medications

Correct metabolic derangements

Manage pain and anxiety

Subspecialty consult

ADDITIONAL READINGCASES

HYPOVOLEMIC SHOCK

DISTRIBUTIVE SHOCK

OBSTRUCTIVE SHOCK

CARDIOGENIC SHOCK

NEUROGENIC SHOCK

OTHERS

Diarrhea Sepsis Pericardial tamponade

Brain tumor Poisonings

DKA Tension pneumothorax

Brain trauma Nephrotic/Nephritic syndrome

Burns Ductal dependent heart lesions

Fluids for newborns

Dengue Massive pulmonary embolism

Anaphylactic shock

Trauma Surgical cases

BURNSParkland Formula

Crystalloid at 4ml/kg x % BSA burned + Maintenance requirement

Give ½ over the first 8 hours

Then ½ over the next 16 hours

*See Burn Assesment Chart for %BSA burned

DENGUEPPS 2010 Recommendations

NOT in Shock

D5LR/ D5NSS/ D50.9NaCl

Maintenance rate using Holliday Segar/Ludan

Correct in 24 hours

With MILD Dehydration

D5LR/ D5NSS/ D50.9NaCl

Maintenance rate (Ludan) + Mild Dehydration (Ludan)

Give ½ in the first 8 hours

Give the rest in the remaining 16 hours

END

•NELSON’S TEXTBOOK OF PEDIATRICS•HARRIET LANE•PPS DENGUE 2010 GUIDELINES

CASE

1 year old MALE was brought to the ER by his hysterical mother due to sudden generalized tonic clonic convulsions and upward rolling of the eyeballs which occurred five minutes prior to consult. This is reported to be his first attack.

On further investigation, you noted a 3 day history of vomiting followed by diarrhea. The vomiting occurs 2x/day, postprandial, amounting to ½ cup per episode.

The frequency of the diarrhea was 6-8 stools/day amounting to 1 cup/episode, watery, blood streaked;

This was accompanied by fever (tmax 39) and intermittent episodes of abdominal pain;

No known unusual food intake but the child plays with the neighborhood kids a lot and comes home very dirty.

(+) decrease in appetite; Noted progressive decrease in activity

Last urine output noted 9 hours prior to consult;

(+) Family history of BFC – paternal relatives

The rest of the history was unremarkable

PHYSICAL EXAMINATION

Temperature 39; Heart rate 140/ minute;

Respiratory rate 42/min; Blood pressure 90/60

Asleep, arousable; Not in respiratory distress;

Good skin turgor;

Pink, dry lips, no tpc, dry oral mucosa, sunken eyeballs, no clad;

Equal chest expansion, clear breath sounds, no retractions;

Heart with regular rhythm, no murmurs;

Abdomen tympanitic, soft, hyperactive bowel sounds

Full and equal pulses