6663819 Fluids Electrolytes Handout 1

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FLUIDS

FLUIDS

Maintain homeostasis

Ensure adequate tissue perfusion

Help maintain body temperature and cell shape

Help transport nutrients, gases and wastes

Fluids

60% of an adults body weight* 70 Kg adult male: 60% X 70= 42 Liters

Infants = more water

Elderly = less water

More fat = water

More muscle = water

Infants and elderly - prone to fluid imbalance

Factors that influence amount of body fluids:

1. age

- younger people have higher percentage of body fluid than older people

2. gender

- male > women

3. body fats

- obese people have less fluids than thin people

(fat cells contain little water)

Intravascular space - fluid within the blood vessels , contains plasma

- approximately 3L of the average 6L of blood ismade up of plasma

Interstitial space - contains fluids that surround the cell; about 11-12 liters

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Transcellular space - contains 1 L of fluid

ex. Cerebrospinal, pericardial, synovial, intraocular and digestive secretion

Sources of Fluids

Fluid Intake1. Exogenous sources

Fluid intake

oral liquids 1, 300 mlwater in food 1, 000 ml

water produced by metabolism 300 ml

IVF Medications

Blood products

2. Endogenous sources By products of metabolism

secretions

Fluid Output

Sensible loss

Urine - 1, 500 ml

Fecal losses 200 ml

Insensible loss

skin 600 ml

Lungs 300 ml

Third-space fluid shift/

Third spacing- loss of ECF into a space that does not contribute to equilibrium between ICF and

ECF

- ie ascites, burns, peritonitis, bowel obstruction, massive bleeding

Mechanisms of Body Fluid Movement (i.e. movement of solutes, solvents across

different extracellular locations)A. Osmosis: water is mover; water moves from lower concentration to higher

concentration

1. Normal Osmolality of ICF and ECF: 275 295 mOsm/kg

Types of solutions according to osmolality

a. Isotonic: all solutions with osmolality same as that of plasmaBody cells placed in isotonic fluid: neither shrink nor swell

b. Hypertonic: fluid with greater concentration of solutes than plasma

Cells in hypertonic solution: water in cells moves to outside to equalize

concentrations: cells will shrink

c. Hypotonic: fluid with lower concentration of solutes than plasmaCells in hypotonic solution: water outside cells moves to inside of cells: cells will

swell and eventually burst (hemolyze)

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Different intravenous solutions, used to correct some abnormal conditions,categorized according to osmolality:

a. Hypertonic: 5%glucose, 45% NaCl solution

b. Isotonic: 9% NaCl, Lactated Ringers solution

c. Hypotonic: 45% NaCl

B. Diffusion: solute molecules move from higher concentration to lower

concentration1. Solute, such as electrolytes, is the mover; not the water

2. Types: simple and facilitated (movement of large water-soluble molecules)

C. Filtration: water and solutes move from area of higher hydrostatic pressure to

lower hydrostatic pressure

1. Hydrostatic pressure is created by pumping action of heart and gravity against

capillary wall

2. Usually occurs across capillary membranes

D. Active Transport: molecules move across cell membranes against concentrationgradient; requires energy, e.g. Na K pump

Transport Mechanisms

fluids from different compartments move from one compartment to the other tomaintain fluid balance.

movement is dictated by the transport mechanism principle :A. PASSIVE

B. ACTIVE TRANSPORT

A. Passive Transport Process

substances transported across the membrane w/o energy input from the cell

- high to low concentration

2 Types of Passive Transport

1. Diffusion substances/solutes move from high concentration to low concentration

ie exchange of O2 and CO2 b/w pulmonary capillaries and alveoli

2. Filtration water and solutes forced through membrane by fluid or hydrostatic

pressure from intravascular to interstitial area- solute containing fluid (filtrate) from higher pressure to lower pressure

- an example of this process is urine formation

- increased hydrostatic pressure is one mechanism producing edema

B. Active Transport Process

- Cell moves substances across a membrane through ATP because:

- They may be too large

- Unable to dissolve in the fat core

- Move uphill against their concentration gradient

Types of Active Transport

1. Active transport requires protein carriers using ATP to energize itie Amino acids

Sodium potassium pump 3Na out, 2K in

2. Endocytosis moves substances into the cell

3. Exocytosis moves substances out of the cell

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Osmosis

Movement of water from low solute to high solute concentration in order to

maintain balance between compartments. Osmotic pressure amount of hydrostatic pressure needed to stop the flow ofwater by osmosis

Oncotic pressure osmotic pressure exerted by proteins

Types of Fluid

Tonicity

This is the concentration of solutes in a solution

A solution with high solute concentration is considered as HYPERTONIC

A solution with low solute concentration is considered as HYPOTONIC

A solution having the same tonicity as that of body fluid or plasma is consideredISOTONIC

In a HYPERTONIC solution, fluid will go out from the cell, the cell will shrink.

In a HYPOTONIC solution, fluid will enter the cell, the cell will swell.

In an ISOTONIC solution, there will be no movement of fluid.

Isotonic Fluid- no movement of fluid.

Isotonic Fluids

0.9% NaCl/ Normal Saline/NSS-Na=154

-Cl=154

-308 mOsm/L- not desirable as routine maintenance solution

- only solution administered with blood products

Rx: hypovolemia, shock, DKA, metabolic alkalosis, hypercalcemia, mild NA

deficitCI: caution in renal failure, heart failure and edema

D5W - 5% Dextrose in water- 170 cal and free water- 252 mOsm/L

Rx: hypernatremia, fluid loss and dehydrationCI: early post op when ADH inc d/t stress, sole treatment in FVD (dilutes plasma), head

injury (inc ICP), fluid resuscitation (hyperglycemia), caution in renal and cardiac dse

(fluid overload), px with NA deficiency (peripheral circulatory collapse and anuria)

10% Dextran 40 in 5% Dextrose isotonic (252 mOsm/L)

Lactated Ringers Solution isotonic- Na 130 mEq/L

- K 4 mEq/L-Ca 3 mEq/L

- Cl 109 mEq/L- 273 mOsm/L

Rx:hypovolemia, burns, fluids lost as bile/diarrhea, acute blood loss

CI: ph>7.5, lactic acidosis, renal failure(cause HyperK)

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Hypotonic Fluid

- fluid will enter the cell, the cell will swell

Hypotonic Fluids

0.45% NaCl (half strength saline)

- provides Na, Cl and free water- Na 77 mEq/L

- Cl 77 mEq/L

- 154 mOsm/LRx: hypertonic dehydration, Na and Cl depletion, gastric fluid loss

CI : 3rd space fluid shifts and inc ICP

Hypertonic Fluid- fluid will go out from the cell, the cell will shrink

Hypertonic Fluids

3% NaCl (hypertonic saline)- no calories

- Na 513 mEq/L- Cl 513 mEq/L

-1026 mOsm/L

Rx: critical situations to treat HypoNa, assist in removing ICF excessCI: administered slowly and cautiously (IVF overload and pulmonary edema)

5% NaCl

D10W - 10% Dextrose in water hypertonic (505 mOsm/L) D10W - 20% Dextrose in water hypertonic (1011 mOsm/L)

D50W - 50% Dextrose in water hypertonic (1700 mOsm/L) D5NS - 5% Dextrose & 0.9NaCl hypertonic (559 mOsm/L) D10NS - 10% Dextrose & 0.9NaCl hypertonic (812 mOsm/L)

D5LR - 5% Dextrose in Lactated Ringers hypertonic (524 mOsm/L

Colloid solutions

Dextran 40 in NS or 5% D5W- volume/plasma expander

- decrease coagulation

- remains for 6H in circulatory system

Rx: hypovolemia in early shock, improve microcirculation (dec RBC aggregation)

CI: hemorrhage, thrombocytopenia, renal disease and severe dehydration

Mechanisms that Regulate Homeostasis:

How the body adapts to fluid and electrolyte changesA.Thirst: primary regulator of water intake (thirst center in brain)

B.Kidneys: regulator of volume and osmolality by controlling excretion of water and

electrolytesC.Renin-angiotension-aldosterone mechanism: response to a drop in blood pressure;

results from vasoconstriction and sodium regulation by aldosterone

D.Antidiuretic hormone: hormone to regulate water excretion; responds to osmolality andblood volume

E.Atrial natriuretic factor: hormone from atrial heart muscle in response to fluid excess;causes increased urine output by blocking aldosterone

Organs involved in homeostasis

Kidneys

Lungs Heart

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Adrenal glands

Parathyroid glands

Pituitary glands Other mechanisms

1. baroreceptor

2. renin-angiotensin-aldosterone system3. ADH and thirst

4. osmoreceptor

5. release of atrial natriuretic peptide

Organs involved in homeostasisA. Kidney - vital to regulation of fluid and electrolytes

- filters 170 L of plasma everyday

- urine output in an adult is 1-2 liters / day

- releases RENIN

- regulates sodium and water balance

Functions include :

1. regulation of ECF volume and osmolality by selective retention and excretion ofbody fluids

2. regulation of electrolytes levels in the ECF by selective retention of needed

substance and excretion of unneeded substance3. regulation of pH of the ECF by retention of hydrogen ions

4. excretion of metabolic waste and toxic substances

B. Heart and blood vessels - pumping action of the heart to maintain renal perfusionC. Lungs - maintain homeostasis through exhalation

- remove approximately 300 400 ml of water daily-loss is greater if there is increase in respiratory depth or rate or in dry climate

D. Pituitary function - hypothalamus manufactures ADH

- ADH used for water retention or excretion of water by the kidney and in regulatingblood volume

E. Adrenal function - secretes aldosterone, has effect on fluid regulation- secretes also cortisol has a fraction effect of aldosterone

F. Parathyroid function - regulates calcium and phosphate

- influences bone resorption , Ca absorption from the intestine, and Ca reabsorption fromthe renal tubules

Other mechanisms:1. baroreceptors - are small nerve receptors that detect pressure within blood vessels and

transmit information to the CNS

- responsible for monitoring for circulating volume and they regulate sympathetic andparasympathetic neural activity and endocrine function

types: low-pressurehigh-pressure

High pressure - are nerve endings in the aortic arch and in the cardiac sinus- another is seen in the afferent arteriole of the juxtaglomerular apparatus of nephron

Low pressure - are located in cardiac atria, particularly in the left atria

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2. renin-angiotensin aldosterone system:

- renin : an enzyme that convert angiotensinogen to

angiotensin I, it is released from juxtaglomerular cells of the kidney to decrease renalperfusion

then angiotensin I is converted to angiotensin II by angiotensin converting enzymes ,w/cis a vasoconstrictor w/c in turn increases arterial perfusion and stimulates thirst,

aldosterone is released

factors that influence aldosterone secretion:

1. increased release of renin

2. increased serum potassium3. decreased Na serum

4. ACTH increase

3. ADH and THIRST - have important role in maintaining sodium concentration andoral intakes of fluids

thirst: oral intake is controlled by thirst center located in the hypothalamus :

serum osmolality

or blood volume

stimulate thirst center

ADH - controls water excretion- determines concentration of urine

4. osmoreceptors - located in the surface of hypothalamus- sense changes in Na concentration

osmotic pressure (neurons become dehydrated)

releases impulses to

posterior pituitary to

release ADH

increases permeability of membrane to

H2O (kidney, causingreabsorption of water and decreased urine output)

5. Release of atrial natriuretic peptide - released by cardiac cells in the atria of the heartin response to increased atrial pressure

- action of this is direct opposite of RAAS and decreases blood pressure and volume

- ANP level is 20 to 77 pg /ml (ng/ml)

Regulation of Body Fluid1. The Kidney

Regulates primarily fluid output by urine formation 1.5L

Releases RENIN

Regulates sodium and water balance

2. Endocrine regulation

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thirst mechanism thirst center in hypothalamus

ADH increases water reabsorption on collecting duct

Aldosterone increases Sodium and water retention retention in the distal

nephron

ANP Promotes Sodium excretion and inhibits thirst mechanism

3. Gastro-intestinal regulation

- GIT digests food and absorbs water

- Only about 200 ml of water is excreted in the fecal material per day

4. Heart and Blood Vessel Functions

- pumping action of heart circulates blood through kidneys

5. Lungs insensible water loss through respirationOther Mechanisms1. Baroreceptors carotid sinus and aortic arch- causes vasoconstriction and increased blood pressure

Dec arterial pressure SNS inc cardiac rate, contraction, contractility, circulatingblood volume, constriction of renal arterioles and increased aldosterone

2. Osmoreceptors surface of hypothalamus senses changes in Na concentration

Inc osmotic pressure neurons dehydrated release ADH

KIDNEY

Nephron: glomerulus and tubule

Filtration Retention/ Reabsorption

Excretion

170-180 L/day Filtrate= urine

(1-2 L urine/ day)

Fluid excess excretes dilute urine (rids body of excess fluid while conserving

electrolytes)

ADH (Antidiuretic hormone)

Vasopressin

Water-retainer

Hypothalamus produces ADH

Posterior pituitary gland stores and releases ADH

Restores blood volume by reducing diuresis and increasing water retention

ADH

Low blood volume/ Pituitary glandIncreased serum osmolality secretes ADH

into the bloodstream

ADH causes the Water retentionKidneys to retain water increases blood

volume/ decreases

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Aldosterone

Angiotensin II Aldosterone Sodium and

stimulates the causes kidneys water retention

adrenal glands to to retain sodium leads to increasedproduce Aldosterone and water fluid volume and

sodium level

Aldosterone Disorders

Addisons Disease Abnormally low aldosterone

Serum Na is low, serum potassium is high

FVD

Cushings Disease Abnormally high aldosterone

Serum Na is high, serum potassium is low

FVE

ANP (Atrial Natriuretic Peptide)

Cardiac hormone

Stored in the cells of the atria

Released when atrial pressure increases

Counteracts the effects of the RAAS by decreasing blood pressure and reducingintravascular blood volume

When blood volume and BP rise and stretch the atria, ANP shuts off RAAS

ANP

Suppresses serum renin levels

Decreases aldosterone release from the adrenal glands

Increases glomerular filtration, which increases urine excretion of sodium andwater

Decreases ADH release from the posterior pituitary gland

Reduces vascular resistance by causingvasodilation

Examples of causes of atrial stretching

(which result to increased release of ANP)

Orthostatic changes

Atrial tachycardia

High sodium intake

Sodium chloride infusions

Use of drugs that cause vasoconstriction

Physiology/pathophysiology

increased blood volume

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increased blood pressure

increased stretch of atria

increased ANP release

vascular resistancedecrease ADH increase GFR w/c increases

urinary excretion of Na and

Decrease blood pressure water

Suppression of serum renin

decrease vascular volumedecrease BP, decrease preload and afterload

Thirst mechanism

Regulated by the hypothalamus

Stimulated by an increase in ECF and drying of mucous membrane

Causes a person to drink fluids, which is absorbed by the intestines, moved to thebloodstream and distributed between the compartments

Leads to increased amount of fluid in the body and a decrease in concentration ofsolutes

Decreased Blood Volume

THIRST mechanism

ADH secretion is increased

ANP secretion is decreased

RENIN secretion is increased

BARORECEPTOR vasoconstricton

ALDOSTERONE secretion is increased

Increased Blood Volume

NO THIRST mechanism ADH secretion is decreased

ANP secretion is increased

RENIN secretion is increased

BARORECEPTOR vasodilation

ALDOSTERONE decreased

Fluid status can be assessed through:

Mucus membrane Skin integrity

Body weight Jugular vein

BP, PAWP 6-12 mm Hg

CVP (most accurate) 0-7 mm Hg or 5-10 cm of H2O I&O

Pulse

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Temperature

Lung sound and heart sound

Urine output Urine SG 1.005-1.030

Hematocrit 48%

Plasma osmolality LOC

Evaluation of fluid statusOsmolality concentration of fluid that affects movement of water between fluid

compartments by osmosis

- measures the solute concentration per kg in blood and urine

- measure of solutions ability to create osmotic pressure and affect themovement of sodium

- reported as mOsm/kg

- normal value= 280-300 mOsm/kg

Osmolarity concentration of solutions- measures the solute concentration per L in blood and urine

- mOsm/L

urine specific gravity - measures the kidneys ability to excrete or conserve water

urine specific gravity: 1.010 - 1.025

Blood urea nitrogen - made up of urea, end product of metabolism of protein

10-20mg/dl (3.5-7mmol/l)

BUN: not most reliable indicator of renal disease BUN:creatinine ratio better indicatorNormal 10:1.

increased BUN due to:1. renal function

2. GI bleeding

3. dehydration4. increased protein intake

5. fever and sepsis

decreased BUN due to :

1. end-stage liver disease

2. low protein intake

3. starvation4.condition that expands fluid volume

ex. pregnancy

Creatinine

byproduct of muscle metabolism & excretedby kidneys regardless of fluid intake, diet, etc.

measures kidney function; 50% renal function lost BEFORE in serumcreatinine level

better indicator of renal function

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.7 to 1.5 mg/dl

Hematocrit - indication of hydration status

- measures the volume percentage of red blood

cells in whole blood and normally ranges from

44% to 52% for male

39% - 47% in females

hematocrit due to: 1. dehydration

2. polycythemia

hematocrit due to: 1. overhydration

2. anemia

Urine sodium values: change with sodium intake and status of fluid volume

- normal level ranges from 50 - 220mEq/24h

- used to assess volume status and in the diagnosis of hyponatremia and acute

renal failure

Fluid volume disturbances

I and O must be equal

2.5 L per day

Fluid volume deficit (hypovolemia) Fluid volume excess (hypervolemia)

I&O Imbalance

Fluid Volume Deficit

output, normal intake

Normal output, intake

No intake

Fluid Volume Excess

intake, normal output

Normal intake, output

No output

1. Fluid volume deficit

- occurs when loss of ECF volume exceeds the intake of fluid

causes:

1. abnormal fluid losses

vomiting, diarrhea, GI suctioning and sweatingDiabetes Insipidus

Adrenal insufficiency

Osmotic diuresis

Hemorrhage3rd space fluid shift

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2. decreased intake

signs and symptoms :1. acute weight loss

2. decreased skin turgor

3. oliguria4. concentrated urine5. postural hypotension, weak and rapid heart rate

6. flattened neck veins, decreased CVP, cool clammy skin

7. Thirst, anorexia

8. Muscle weakness and cramps

Assessment of FVD

ICFcellular dehydration

ITFskin poor skin turgor

IVFartery BP, pulse (rapid thready)

vein CVP

assessment :

1. elevated BUN

2. elevated Hct.

3. serum electrolyte changes may also exist1. hypokalemia- GI and renal losses

2. hyperkalemia- adrenal insufficiency

3. hyponatremia- increased thirst and ADH release

4. hypernatremia- increased insensible losses and

diabetes insipidus

Medical Management

Oral intake when mild

IV route, acute or severe

Isotonic fluids ie LR lactated ringers or .9% NaCl for hypotensive patients to expand

plasma volumeNursing Management

measure I and O accurately

monitoring of body weight- loss of .5 kg means a loss of 500ml

monitoring of V/S

skin turgor assessment

Assess CVP, LOC, breath sounds and skin color Monitor urinary concentration

Monitor mental function

2. fluid volume excess (hypervolemia)

- refers to an isotonic expansion of the ECF caused by the abnormal retention of water

and Na in approx. same proportion

- usually 2nd to increase in total body Na content

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Pathophysiology:

1. related to simple fluid overload

2. diminished function of the homeostatic

mechanism responsible for regulating fluid balance

Causes of FVE

Heart failure

renal failure

cirrhosis of the liver

consumption of excessive amount of salt

Excessive administration of Na containing fluids in a patient w/ impaired regulatorymechanism

SIADH

Clinical Manifestations

Distended neck veins Tachycardia

Inc weight

Increased urine output

Shortness of breath and wheezing/ crackles

Inc CVP

Edema

increased BP

increased pulse pressure

Assessment of FVE

ICFcellular edema - LOC

pulmonary edema - crackles (bibasilar), wheezing,

shortness of breath, Inc RR

ITFskin - bipedal pitting edema, periorbital edema and ANASARCA

IVFartery - BP, pulse (rapid bounding)

vein - CVP

Edema

common manifestation of FVE

d/t inc capillary fluid pressure, decreased capillary oncotic pressure, increased interstitialoncotic pressure

Localized or generalized

Etiology: obstruction to lymph flow, plasma albumin level < 1.5-2 g/dl, burns andinfection, Na retention in ECF, drugs

Labs: Dec Hct, respiratory alkalosis and hypoxemia, dec serum Na and osmolality, incBUN Crea, Dec Urine SG, dec urine Na level

Mgmt: diuretics, fluid restriction, elevation of extremities, elastic compression stockings,paracentesis, dialysis

Laboratory (FVE)

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Dec BUN

Dec Hct

CRF serum osmolality and Na level dec

chest x-ray may reveal pulmonary congestion

Medical Management Discontinue administration of Na solution

Diureticsie Thiazide block Na reabsorption in

distal tubule

Loop diuretics block Na reabsorption

in ascending loop of Henle

Restrict fluid and salt intake

Dialysis

Nursing Management

Measure intake and output Weigh patient daily

2 lb wt gain = 1 L fluid

Assess breath sounds

Monitor degree of edemaie ambulatory feet and ankles

bedridden sacral area

Promote rest favors diuresis/inc venous return

Administer appropriate medication

Electrolytes

elements or compounds when dissolved in water will dissociate into ions and are able toconduct an electric current.

FUNCTIONS:

1. Regulate fluid balance and osmolality

2. Transmission of nerve impulse

3. Stimulation of muscle activity

ANIONS - negatively charged ions: Bicarbonate, chloride, PO4-, CHON

CATIONS - positively charged ions: Sodium, Potassium, magnesium, calcium

Cations

Sodium , Potassium , Calcium , Magnesium , hydrogen ions

Anions

Chloride, bicarbonate , phosphate, sulfate, proteinate ions

Sodium - positively charged ions , major cation in the ECF-important in regulating the volume of body fluids

-retention of Na- associated with fluid retention

-loss of Na- decreased volume of body fluids

Potassium - major cation in the ICF

Chloride - major anion in the ECF

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Phosphate - major anion in the ICF

Regulation of Electrolyte Balance

1. Renal regulation

Occurs by the process of glomerular filtration, tubular reabsorption and tubular secretion

Urine formation If there is little water in the body, it is conserved

If there is water excess, it will be eliminated

2. Endocrinal regulation

Aldosterone promotes Sodium retention and Potassium excretion

ANP promotes Sodium excretion

Parathormone increased bone resorption of Ca, inc Ca reabsorption from renal tubuleor GI tract

Calcitoninoppose PTH Insulin and Epinephrine promotes uptake of Potassium by cellsThe Cations

SODIUM

POTASSIUM

CALCIUM

MAGNESIUMSODIUM (Na)

MOST ABUNDANT cation in the ECF

135-145 mEq/L Aldosterone increases sodium reabsorption

ANP increases sodium excretion

Cl accompanies Na

FUNCTIONS:

1. assists in nerve transmission and muscle contraction

2. Major determinant of ECF osmolality

3. Primary regulator of ECF volume

a. HYPERNATREMIA

Na > 145 mEq/L

Assoc w/ water loss or sodium gain

Etiology: inadequate water intake, excessive salt ingestion /hypertonic feedings w/o

water supplements, near drowning in sea water, diuretics, Diabetes mellitus/ Diabetes Insipidus

S/SX: polyuria, anorexia, nausea, vomiting, thirst, dry and swollen tongue, fever, dry and flushed

skin, restlessness, agitation, seizures, coma, muscle weakness, crackles, dyspnea, cardiac

manifestations dependent on type of hypernatremia

Dx: inc serum sodium and Cl level, inc serum osmolality, inc urine sp.gravity, inc urine

osmolality

Mgmt: sodium restriction, water restriction, diuretics, isotonic non saline soln. (D5W) or

hypotonic soln, Desmopressin Acetate for Diabetes Insipidus

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Nsg considerations

History diet, medication

Monitor VS, LOC, I and O, weight, lung sounds

Monitor Na levelsOral care

initiate gastric feedings slowlySeizure precaution

b. HYPONATREMIA

Na < 135 mEq/L

Etiology: diuretics, excessive sweating, vomiting, diarrhea, SIADH, aldosteronedeficiency, cardiac, renal, liver disease

Dx: dec serum and urine sodium and osmolality, dec Cl

s/sx: headache, apprehension, restlessness, altered LOC, seizures( 5.0 mEq/L

Etiology: IVF with K+, acidosis, hyper-alimentation and excess K+ replacement,decreased renal excretion, diuretics, Cancer

s/sx: nerve and muscle irritability, tachycardia, colic, diarrhea, ECG changes, ventricular

dysrythmia and cardiac arrest, skeletal muscle weakness, paralysis

Dx: inc serum K levelECG:peaked T waves and wide QRS

ABGs metabolic acidosis

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Mgmt:

K restriction (coffee, cocoa, tea, dried fruits, beans, whole grain breads, milk, eggs)

diuretics

Polystyrene Sulfonate (Kayexalate)

IV insulinBeta 2 agonist

IV Calcium gluconate WOF HypotensionIV NaHCo3 alkalinize plasma

Dialysis

Nsg consideration:

Monitor VS, urine output, lung sounds, Crea, BUN

monitor K levels and ECG

observe for muscle weakness and dysrythmia, paresthesia and GI symptoms

b. HYPOKALEMIA

K+ < 3.5 mEq/L

Etiology: use of diuretic, corticosteroids and penicillin, vomiting and diarrhea, ileostomy,villous adenoma, alkalosis, hyperinsulinism, hyperaldosteronism

s/sx: anorexia, nausea, vomiting, decreased bowel motility, fatigue, muscle weakness, legcramps, paresthesias, shallow respiration, shortness of breath, dysrhythmias and increased

sensitivity to digitalis, hypotension, weak pulse, dilute urine, glucose intolerance

Dx: dec serum K level

ECG - flattened , depressed T waves, presence of U waves

ABGs - metabolic alkalosis

Medical Mgmt:

diet ( fruits, fruit juices, vegetables, fish, whole grains, nuts, milk, meats)

oral or IV replacement

Nsg mgmt:

monitor cardiac function, pulses, renal function

monitor serum potassium concentration

IV K diluted in saline

monitor IV sites for phlebitis

Normal ECG

Hypokalemia

Hyperkalemia

Regulation:

GIT absorbs Ca+ in the intestine with the help of Vitamin D

Kidney Ca+ is filtered in the glomerulus and reabsorbed in the tubules

PTH increases Ca+ by bone resorption, inc intestinal and renal Ca+ reabsorption andactivation of Vitamin D

Calcitonin reduces bone resorption, increase Ca and Phosphorus deposition in bonesand secretion in urine

a. HYPERCALCEMIA

Serum calcium > 10.5 mg/dL

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Etiology: Overuse of calcium supplements and antacids, excessive Vitamin A and D,malignancy, hyperparathyroidism, prolonged immobilization, thiazide diuretic

s/sx: anorexia, nausea, vomiting, polyuria, muscle weakness, fatigue, lethargy

Dx: inc serum CaECG: Shortened QT interval, ST segments

inc PTH levels

xrays - osteoporosis

Mgmt:0.9% NaCl

IV Phosphate

Diuretics Furosemide

IM Calcitonin

corticosteroids

dietary restriction (cheese, ice cream, milk, yogurt, oatmeal, tofu)

Nsg Mgmt:

Assess VS, apical pulses and ECG, bowel sounds, renal function, hydration status

safety precautions in unconscious patients

inc mobility

inc fluid intake

monitor cardiac rate and rhythm

b. HYPOCALCEMIA

Calcium < 8.5 mg/dL

Etiology: removal of parathyroid gland during thyroid surgery, Vit. D and Mg deficiency,

Furosemide, infusion of citrated blood, inflammation of pancreas, renal failure, thyroid CA, lowalbumin, alkalosis, alcohol abuse, osteoporosis (total body Ca deficit)

s/sx: Tetany, (+) Chovsteks (+) Trousseauss, seizures, depression, impaired memory,confusion, delirium, hallucinations, hypotension, dysrythmia

Dx:dec Ca level

ECG: prolonged QT interval

Mgmt:Calcium salts

Vit Ddiet (milk, cheese, yogurt, green leafy vegetables)

Nsg mgmtmonitor cardiac status, bleeding

monitor IV sites for phlebitis

seizure precautions

reduce smokingMagnesium Mg

Second to K+ in the ICF

Normal range is 1.3-2.1 mEq/L

FUNCTIONS

1. intracellular production and utilization of ATP

2. protein and DNA synthesis

3. neuromuscular irritability

4, produce vasodilation of peripheral arteries

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a. HYPERMAGNESEMIA

M > 2.1 mEq/L

Etiology: use of Mg antacids, K sparing diuretics, Renal failure, Mg medications, DKA,

adrenocortical insufficiency

s/sx: hypotension, nausea, vomiting, flushing, lethargy, difficulty speaking, drowsiness,dec LOC, coma, muscle weakness, paralysis, depressed tendon reflexes, oliguria, RR

Mgmt: discontinue Mg supplementsLoop diuretics

IV Ca gluconate

Hemodialysis

Nsg mgmt:monitor VS

observe DTRs and changes in LOC

seizure precautions

b. HYPOMAGNESEMIA

Mg < 1.5 mEq/l

Etiology: alcohol w/drawal, tube feedings, diarrhea, fistula, GIT suctioning, drugs ieantacid, aminoglycosides, insulin therapy, sepsis, burns, hypothermia

s/sx: hyperexcitability w/ muscle weakness, tremors, tetany, seizures, stridor, Chvostekand Trousseaus signs, ECG changes, mood changes

Dx: serum Mg levelECG prolonged PR and QT interval, ST depression, Widened QRS, flat T waves

low albumin level

Mgmt:diet (green leafy vegetables, nuts, legumes, whole grains, seafood, peanut butter, chocolate)

IV Mg Sulfate via infusion pump

Nsg Mgmt:seizure precautionsTest ability to swallow, DTRs

Monitor I and O, VS during Mg administration

The Anions

CHLORIDE

PHOSPHATES

BICARBONATES

Chloride (Cl)

The MAJOR Anion in the ECF

Normal range is 95-108 mEq/L Inc Na reabsorption causes increased Cl reabsorptionFUNCTIONS

1. major component of gastric juice aside from H+

2. together with Na+, regulates plasma osmolality

3. participates in the chloride shift inverse relationship with Bicarbonate

4. acts as chemical buffer

a. HYPERCHLOREMIA

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Serum Cl > 108 mEq/L

Etiology: sodium excess, loss of bicarbonate ions

s/sx: tachypnea, weakness, lethargy, deep rapid respirations, diminished cognitive abilityand hypertension, dysrhytmia, coma

Dx: inc serum Cldec serum bicarbonate

Mgmt:

Lactated Ringers soln

IV Na Bicarbonate

Diuretics

Nsg mgmt:

monitor VS, ABGs, I and O, neurologic, cardiac and respiratory changes

b. HYPOCHLOREMIA

Cl < 96 mEq/l

Etiology: Cl deficient formula, salt restricted diets, severe vomiting and diarrhea

s/sx: hyperexcitability of muscles, tetany, hyperactive DTRs, weakness, twitching,muscle cramps, dysrhytmias, seizures, coma

Dx: dec serum Cl level

ABGs metabolic alkalosis

Mgmt:Normal saline/half strength saline

diet ( tomato juice, salty broth, canned vegetables, processed meats and fruits

avoid free/bottled water)

Nsg mgmt:

monitor I and O, ABGs, VS, LOC, muscle strength and movement

Phosphates (PO4)

The MAJOR Anion in the ICF

Normal range is 2.5-4.5 mg/L Reciprocal relationship w/ Ca

PTH inc bone resorption, inc PO4 absorption from GIT, inhibit PO4 excretion fromkidney

Calcitonin increases renal excretion of PO4

FUNCTIONS

1. component of bones

2. needed to generate ATP3. components of DNA and RNA

a. HYPERPHOSPHATEMIA

Serum PO4 > 4.5 mg/dL

Etiology: excess vit D, renal failure, tissue trauma, chemotherapy, PO4 containingmedications, hypoparathyroidism

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s/sx: tetany, tachycardia, palpitations, anorexia, vomiting, muscle weakness,hyperreflexia, tachycardia, soft tissue calcification

Dx: inc serum phosphorus leveldec Ca level

xray skeletal changes

Mgmt:

diet limit milk, ice cream, cheese, meat, fish, carbonated beverages, nuts, dried food,

sardines

Dialysis

Nsg mgmt:

dietary restrictions

monitor signs of impending hypocalcemia and changes in urine output

b. HYPOPHOSPHATEMIA

Serum PO4 < 2.5 mg/dl

Etiology: administration of calories in severe CHON-Calorie malnutrition (iatrogenic),chronic alcoholism, prolonged hyperventilation, poor dietary intake, DKA, thermal burns,

respiratory alkalosis, antacids w/c bind with PO4, Vit D deficiency

s/sx: irritability, fatigue, apprehension, weakness, hyperglycemia, numbness,paresthesias, confusion, seizure, coma

Dx: dec serum PO4 level

Mgmt:oral or IV Phosphorus correction

diet (milk, organ meat, nuts, fish, poultry, whole grains)

Nsg mgmt:

introduce TPN solution gradually

prevent infection

Fluids D1

Electrolytes D2

Acid-Base D3 Burns D3

Shock D4

GUT D5

MASTERY D6

Acid Base Balance

Acid- substance that can donate or release hydrogen ions

ie Carbonic acid, Hydrochloric acid

** Carbon dioxide combines with water to form carbonic acid

Base- substance that can accept hydrogen ions

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Ie Bicarbonate

BUFFER- substance that canaccept or donate hydrogen

- prevent excessive changes in pH

TYPES OF BUFFER1. Bicarbonate (HCO3): carbonic acid buffer (H2CO3)

2. Phosphate buffer

3. Hemoglobin buffer

Dynamics of Acid Base Balance

Acids and bases are constantly produced in the body

They must be constantly regulated

CO2 and HCO3 are crucial in the balance

A HCO3:H2CO3 ratio of 20:1 should be maintained Respiratory and renal system are active in regulation

Kidney- Regulate bicarbonate level in ECF

1. RESPIRATORY/METABOLIC ACIDOSIS

- kidney excrete H and reabsorbs/generates Bicarbonate2. RESPIRATORY/METABOLIC ALKALOSIS

- kidney retains H ion and excrete Bicarbonate

Lung- Control CO2 and Carbonic acid content of ECF

1. METABOLIC ACIDOSIS

- increased RR to eliminate CO2

2. METABOLIC ALKALOSIS- decreased RR to retain CO2

pH - measures degree of acidity and

alkalinity- indicator of H ion concentration

- Normal ph 7.35-7.45

ACIDOSIS- decreased pH; < 7.35- increased Hydrogen

ALKALOSIS- increased pH-; > 7.45- decreased Hydrogen

ACUTE AND CHRONIC

METABOLIC ACIDOSIS

- Low pH

- Increased H ion concentration

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- Low plasma BicarbonateEtiology: diarrhea, fistulas, diuretics, renal insufficiency, TPN w/o Bicarbonate, ketoacidosis,

lactic acidosis

S/sx: headache, confusion, drowsiness, inc RR, dec BP, cold clammy skin, dysrrythmia, shock

Dx: ABG low Bicarbonate, low pH, Hyperkalemia, ECG changes

Rx: Bicarbonate for pH < 7.1 and Bicarbonate level < 10monitor serum K

dialysis

ACUTE AND CHRONIC

METABOLIC ALKALOSIS

High pH

Decreased H ion concentration

High plasma Bicarbonate

Etiology: vomiting, diuretic, hyperaldosteronism, hypokalemia, excesive alkali ingestion

s/sx: tingling of toes, dizziness, dec RR, inc PR, ventricular disturbances

Dx:ABG pH > 7.45, serum Bicarbonate > 26 mEq/L, inc PaCO2

Rx: restore normal fluid balancecorrect hypokalemia

Carbonic anhydrase inhibitors

ACUTE AND CHRONICRESPIRATORY ACIDOSIS

Ph < 7.35PaCO2 > 42 mmHg

Etiology: pulmonary edema, aspiration, atelectasis, pneumothorax, overdose of seatives, sleep

apnea syndrome, pneeumonia

s/sx: sudden hypercapnia produces inc PR, RR, inc BP, mental cloudinesss, feeling of fullness in

head, papiledema and dilated conjunctival blood vessels

Dx: ABG pH < 7.35PaCO2 - > 42 mmHg

Rx: improve ventilationpulmonary hygiene

mechanical ventilation

ACUTE AND CHRONIC

RESPIRATORY ALKALOSIS

pH > 7.45

PaCO2 < 38 mmHg

Etiology: extreme anxiety, hypoxemia

s/sx: lightheadednes, inability to concentrate, numbness, tingling, loss of consciousness

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Dx: ABG pH > 7.45PaCO2 < 35

dec K

dec Ca

Rx: breathe slowly

sedativeARTERIAL BLOOD GAS ANALYSIS

Evaluating ABGs

Note the pHpH = 7.35 7.45 (normal)

pH = < 7.35 (acidosis)

pH = > 7.45 (alkalosis)

compensated normal pH

uncompensated abnormal pH

2. Determine primary cause of disturbance

2.1 pH > 7.45

a. PaCo2 < 40 mmHg respiratory alkalosis

b. HCO3 > 26 mEq/L metabolic alkalosis

2.2 pH < 7.35

a. PaCo2 > 40 mmHg respiratory acidosis

b. HCO3 < 26 mEq/L metabolic acidosis

3. Determine compensation by looking at the value other than the primary disturbance

4. Mixed acid-base disorders

Thank You!

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6663819 Fluids Electrolytes Handout 1

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Transcript of 6663819 Fluids Electrolytes Handout 1