La Consolacion University Philippines

(formerly University of Regina Carmeli)

Graduate School Department

Name: Allan M. Manaloto, RN Professor: Dr. Amelia Sta. Maria

Subject: Advanced Pathophysiology Date: November 09, 2013

F L U I D & E L E C T R O L Y T E

A N D A C I D – B A S E B A L A N C E

Learning Objectives:

I. Describe the regulation of fluid & electrolyte, & acid–base balance in the body,

including the mechanism involved to maintain homeostasis.

II. . Identify factors affecting normal body fluid, electrolyte, and acid–base balance.

III. Discuss the risk factors for and the causes and effects of fluid, electrolyte, and

acid–base imbalances.

IV. List the major electrolytes and the function of each.

V. Identify the signs and symptoms of the common fluid and electrolyte imbalances.

VI. Teach clients measures to maintain fluid and electrolyte, Acid-base balance.

I. I N T R O D U C T I O N

The cells of the body live in a fluid environment with an electrolyte and acid-

base concentration maintained within a narrow ranged. Fluid and electrolyte,

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Acid-Base Balance is the foundation for understanding many different disease

processes. Changes in Electrolyte concentration affect electrical activity of nerve

and muscle cells, altered Acid-Base balance disrupted cellular functions, and fluid

fluctuation affects blood volume and cellular function.

II. CONCEPT OF FLUIDS

1. Functions:

1. Move electrolytes and water into and out of the cells.

2. Aid digestion.

3. Cleanse body of waste.

4. Regulate body temperature.

5. Lubricate joints and mucous membrane.

The distribution and amount of Total Body Water (TBW) change with age,

and although daily fluid intake may fluctuate widely, body regulates water volume

within a relatively narrow range. Total body Water (TBW) is the sum of fluids within

all body compartments.

Individual TBW Condition Effect

Newborn/ Infant About 75-80% of

body weight

-Greater body surf. area

-Renal: Not yet matured

Prone to Dehydration

Children/

Adolescents

60-65% of body

weight

Men- Increase muscle

mass= greater % of TBW

Women- more fat, lesser

body fluid.

Women are more

prone to Dehydration

due to fat (fats has

tiny amount of water)

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Adult Range 45-75%

(Ave. 60%)

Varies on individual

2. Regulation of Body fluids

Fluids and solutes move constantly within the body. That movement allows body

maintains HOMEOSTASIS.

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Body Fluids

Intracellular Fluid (ICF):

>Fluids within Cell

>2/3 of TBW

Extracellular Fluid (ECF)

>Fluids outside cell

>1/3 of TBW

Interstitial Fluid

>space between cells & outside the blood vessel.

Bathes the cell.

Intravascular Fluid

>blood plasma

A. Membrane Transport: Cellular I & O

Cell continually take in nutrients, fluids and chemical messenger from the

extracellular environment and expel metabolites.

• Passive Transport

- Water and small electrically uncharged molecules moves easily

through pores of plasma membrane. No need for energy

expenditure cell.

- DIFFUSION: natural tendency of substance to move from area of

higher concentration to one of lower concentration.

- FILTRATION: it is the movement of the water and solutes

through membrane because of a greater pushing pressure on

one side of membrane than the other. (Area with greater

Hydrostatic pressure to area with lower Hydrostatic pressure.)

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- OSMOSIS: movement of water across semi-permeable

membrane from region with higher water concentration to lower

water concentration.

Osmotic pressure -the amount of hydrostatic pressure required

to oppose the osmotic movement of water

Oncotic pressure- is the osmotic pressure exerted by proteins.

•Active tranpsort

- Sodium moving out and Pottasium moving into the cell uses the

direct energy of ATP.

- SODIUM- POTTASIUM PUMP: is located in cell membrane and

actively moves Sodium from the cell to the ECF.

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3. Fluid Intake and Losses (per day in a healthy adult)

INTAKE OUTPUT

Ingested: 1300ml Urine: 1500ml

Water in foods: 1000ml Stool: 200ml

Oxidation: 300ml Insensible Lung: 300ml

Skin: 600ml

TOTAL GAIN= 2,600ml TOTAL LOSS= 2,600ml

•Abnormal fluid loss:

Results from physiology imbalance, Examples: Fever,Increased body

temperature, Hemorrhage, emesis, exudates, diaphoresis, thoracentesis.

•Quick way to monitor fluid balance is to: Monitor I &O.

4. Homeostatic mechanism

Organs to remember in maintaining fluid and elctrolyte balance:

C.1. Kidneys

- filter 170L of plasma everyday (Adult), excreting only 1.5L of urine.

- It only takes 20mins of poor perfusion to promote Acute Tubular

Necrosis if not recognzed.

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Fluid Loss

Sensible:

-sweat, feces

Insensible

-Kidney, GIT, Lungs, Skin

C.2. Heart and Blood Vessels

- pumps & carries fluids to organs, esp. kidneys.

C.3. Lungs

- everytime you exhale, water is lost (vapor). Client who experience

rapid breathing (e.g anxiety) may need increase fluids to maintain

Homeostasis.

C.4. Pituitary

- Hypothalamus- posterior pituitary gland secretes ADH. ADH is a water

conserving hormone (causes water retention).

C.5. Adrenal Gland

-secretes Aldosterone (mineralocorticoid, a volume regulator) in which

Result in Sodium retention= Water retention and Pottasium loss.

C.6. Parathyroid Gland

-secretes PTH that causes increase calcium serum by pulling it from

Bones and placing into blood.

C.7. Other Mechanism

-Baroreceptor: responsible for monitoring circulating blood volume.

-Renin-Angiotensin-Aldosterone System (RAAS)

-Anti-Diuretic Hormoe (ADH)

-Osmoreceptors

-Atrial Natriuretic peptide (ANP)

5. Case Considerations

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1. Burned Client

- adequate albumin needed to hold fluid in the vessels may not exist.

Therefore, fluid may leak out of the blood vessel into the tissues that can lead to

shock.

-these client looks: they are in fluid volume excess because of swollen tissues

due to fluid accumulation in tissues and interstitial fluid.

2. Diabetic Client

-when blood has too many glucose/ sugar particles, it causes particle-induced

diuresis. (resulting in fluid loss that can lead to hypovolemia)

3. Gerontologic Client

-Decreased cardiac, kidney, lung function, decreased muscle mass that

increases them a risks of fluid and electrolyte imbalances.

-Dehydration may present as confusion, cognitive impairment

-Monitor I and O accurately.

6. Fluid Volume Disturbances

•Hypovolemia: Fluid Volume Deficit•

•Dehydration: loss of water alone, with increase Sodium level.

•Fluid Volume Deficit (FVD)/ hypovolemia: occurs when water and electrolytes

are lost in the same proportion. Sodium and water are lost in equal amounts from

the vascular space.

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Causes -Decrease intake/ poor appetite, tube feedings,

-Drugs affecting fluid and electrloytes (Ex. Diuretics)

-Diuresis (Diabetes insipidus, Addison’s disease)

-Vomiting, diarrhea, GI suction, hemmorhage

Signs & Symptoms -Acute weight loss -Postural hypotension

-Decrease skin turgor -Weak, rapid pulse; Decrease BP

- Increase RR and Urine SG

Diagnosis -BUN: is elevated and out of proportion to Serum Creatinine

-Serum Electrolytes, Urine SG ang Hg & Hct (increased)

Complications -Shock! - Cogestive heart failure

-Poor Organ perfusion that may lead to ATN and Real Failure

Medical

Management

1. Acute and Severe loss- IV route is required.

2. Intavenous Solution (Isotonic): Lactated Ringer,and 0.9NaCl

because they expand plama volume.

3. Accurate and frequent assessment of LOC, I & O, Skin, CVP,

Weight, and VS.

Nursing

Management

1. Moitor and measure I & O accurately.

2. Weigh client daily.

3.Observe for weak, rapid pulse.

4. Inspect Skin turgor (thigh, forehead and sternum) and Tongue

(may become smaller bec. of fluid loss) regularly.

•Hypervolemia: Fluid Vloume Excess•

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•Fluid volume excess (FVE): is the expansion of the ECF caused by abnormal

retention of watera and sodium. “Isotonic overhydration”.

Causes -diminished fuction of homeostatic mech. Eg.: Heart failure, Renal

failure, liver cirrhosis.

-excessive amout of salt consumption

-Medication: Steroids; Albumin infusion; Blood product admin.

Signs & Symptoms -Jugular vein distention, bounding pulse, tachycardia

-Abnormal breath sounds (fluid collect- lung)

-Polyuria, Dyspnea, Edema- weight gain

-Increased BP and CVP

Diagnosis -Decreased hemoglobin & Hct, Decreased Sodium electrolytes

-BUN and Crea: Increased means kidney not functioning properly

and not excreting fluid.

Medical

Management

1. Management is directed at the cause. (eg. Excessive sodium

admin- discontinue infusion).

2. Pharmacologic: Diuretics

Thiazide (Hydrochlorothiazide;Metozalone)

-for mild to moderate hypervolemia

-blocks sodium reabsoption at distal tubule

Loop Diuretic (Furosemide, Bumetanide, Torsemide)

-for severe hypervolemia

-block sodium reabsorption in loop of henle

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3. Nutritional Management: mild sodium restriction to 250mg/day.

Drink distilled water.

Nursing

Management

1. Measure I & O and Body weight.

2. Assess breath sounds.

3. Assess edema: feet, hands, and sacral area.

III. CONCEPT OF ELECTROLYTES

Electrolytes are elements that, when dissolved in water, acquire an electrical

charge. Cations are positively charged (Sodium, Calcium, Pottasium, Magnesium

and Hydrogen ions), Anions are negatively charged (Chloride, Phosphate,

Bicarbonate, and Sulfate).

• Functions of electrolytes:

-Water distribution

-acid-base balance

-transmit nerve impulses

•Abnormal Electrolyte losses:

-Vomiting

-NG Suctioning

-Drainage (wounds)

-Diarrhea, Diuretics

•Causes of Excess electrolyte in blood:

-Kidney trauma/ disease

-Massive blood transfusion

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-Crushing injuries/ chemotherapy

Note: Standard treatment to client with Fluid and Electrolyte imbalances- IV therapy.

1. SODIUM

Values >Normal Adult level: 135-145mEq/L.

>90% of ECF Cations (Chief electrolyte in the ECF is

Sodium).

Functions →along with Anions (Chloride and Bicarbonate) they

regulate osmotic forces and therefore regulate water

balance.

→assist generation and transmission of nerve impulses.

→assist in Sodium-Potassium pump in cell membrane.

→regulates osmolality.

Food Sources →bacon, ham, cheese processed, catsup, mustard, relishes,

canned vegies

→bread, cereals, snack food

Concept >Excretion of Sodium retains Potassium. Sodium is the only

electrolyte affected by water. Sodium level decreases when

there is high amount of water in the body, while sodium level

decreases when there is little amount of water in the body.

Regulation >Sodium is regulated by ADH, Thirst, and RAAS system in

the body.

SODIUM IMBALANCES

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HYPERNATREMIA HYPONATREMIA

Value Sodium level >145 mEq/L Less than 135mEq/L

Causes •Acute Sodium gain: Infection,

Renal failure, High Na Intake

•Net loss of Water:

Hyperventilation, watery diarrhea,

DI, Polyuria

•Not enough sodium in ECF or too

much water diluting the blood.

•Inadequate Intake, Diuresis,

Diaphoresis, Diarrhea, SIADH

Signs/

Symptoms

→ Dry, sticky mucus membrane,

swollen tongue, decrease saliva

→Change in LOC, Tachycardia,

decreased heart contractility

→Poor skin turgor, dry mucosa,

abdominal cramping

→Neuro changes: altered LOC,

cerebral edema, Coma

→Anorexia, exhaustion

Diagnosis →Serum Elec (Increase Na)

→Increase urine SG,

decreased CVP

→Decreased serum sodium, and

Urine SG

Treatment 1. Determine first the cause of

Hypernatremia.

2. Restrict all forms of Sodium

3. Infuse hypotonic Electrolyte

solution (e.g. 0.3 NaCl)

1. Key is assessment.

( Decreased Intake/ Increased Na

loss?, Excessive water in

vascular?)

3. Sodium Replacement. IVF-

LRS or Isotonic saline.

4. Water restriction

Nursing

Management

1. Carefully monitor fluid I & O.

2. Take note of pt’s thirst,

1. Early detection and treatment.

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elevated temp, and history of

meds taken.

3. Monitor chages in behavior.

2. Monitor fluids and body wt

3. Note abnormal losses of Na or

gains of water, GI manifestation

and CNS and monitor serum Na.

4. Encourage foods high in

Sodium, if applicable. And Restrict

fluid intake.

2. POTASSIUM

Values >Normal Adult level: 3.5-5.0 mEq/L.

>98% of body’s potassium is inside cell. (ICF)

Functions →skeletal and smooth muscle cotraction.

→transmission of electrical impulses.

Note: Sodium and Potassium are inversely related: if one

is up, the other is down. Stomach contains large amount of

potassium.

Food Sources →peaches, bananas, apricots, oranges, melons, raisins,

prunes, brocolli, potatoes, meat, milk

→processed foods, whole grains, dairy products

POTASSIUM IMBALANCES

HYPERKALEMIA HYPOKALEMIA

Value Serum potassium >5.0 mEq/L Less than 3.5 mEq/L

Causes •Decreased renal excretion of •Reduce intake, GI loss- vomiting,

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kidney, Burns, tissue damage

•Meds: KCL, Heparin, ACE

inhibitors, Captopril, NSAID

•Acidosis

diarrhea, GI suction

•K-losing diuretics, altered Acid-

base, Meds- Corticosteroids,

amphotericin B, Kidney disease,

Alkalosis

Signs/

Symptoms

→ Begins with muscle twitching,

hyperactive muscles with tingling

and burning sensation

→Progress to numbness around

the mouth, weakness and flaccid

paralysis.

→Diarrhea, Cardiac arrythmia

→ (mild losses are asymptomatic)

Sever hypoKalemia: may lead to

death due to heart/ respi failure

→Cramps first then, muscular

weakness and flaccid paralysis,

hyporeflexia

→Slow, DOB, weak and irregular

pulse, decreased LOC, N/V.

Diagnosis →ECG: Peaked T-wave, Flat or

no P-wave, wide QRS complex

→Increased serum K, ABG –

metabolic acidosis.

→ECG: flat/inverted T-wave, ST

segment depression, elevated U-

wave.

→Decreased serum K.

Treatment 1. Emergency pharma: give IV Ca

gluconate- to antagonize the

adverse heart conduction. (If BP

and HR drops, STOP the

infusion).

1. Admin of 40-80 mEq/L of K/day.

(IV route: KCL, K+ acetate).

2. Potassium should be admin

only after adequate urine flow.

Decreased urine vol (less 20ml/hr)

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(IV) Regular Insulin- shift

potassium into cells.

Sodium bicarb- needed to

alkalinize the plasma and cause

temp. potassium shift to cells.

for 2 consecutive hours is an

indication to stop K+ admin.

NOTE: Admin of Potassium (max.

conc.) is 20mEq/L and rate no

faster than 10-20 mEq/L.

Potassium is NEVER admin by IV

push or IM.

Nursing

Management

1. Observe signs of muscle

weakness and dysrhythmias.

2. Always verify increase/

abnormal result of serum K.

3. Adhere to Potassium

restriction.

Foods low in K: butter, margarine,

sugar, cranberry juice, jellybeans,

honey, hard candy, root beer.

1. Monitor ECG and S/sx of K

deficit.

2.Health teachings on Potassium

rich foods.

3. CALCIUM

Values >Normal Adult level: 9.0-10.5 mg/dL

>more than 99% of body’s calcium is in skeletal system

Functions →needed for vit. B12 absorption, acts like SEDATIVE on

muscle, nerve impulse transmission, blood clotting, muscle

contraction and relaxation.

→promotes strong bones and teeth.

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→Inverse relatioship with Phosphorus.

Food Sources →milk, cheese, dried beans, canned salmons , sardines

→fresh oysters, green leafy vegetables

Concept >As Ionized Serum Ca decrease- PTH is secreted by

parathyroid gland and thus, Increased Ca absorption of GIT,

Increased reabsorption from renal tubule, & releases Ca

from the bone.

CALCIUM IMBALANCES

HYPERCALCEMIA HYPOCALCEMIA

Value Calcium level >10.5 mg/dL Less than 9.0mg/dl

Causes •Hyperparathyroidism,

Immobilization, Increase Ca and

vit. D Intake, Thiazide diuretics

•primary

hypoparathyroidism/surgical,

radical neck dissection, inflammed

pancreas Vit D consumption is

inadequate and Mg def.

•Alcohol abuse, Meds (caffeine,

corticosteroids, Loop diuretics)

Signs/

Symptoms

→ Reduced neuromuscular

excitability, decrease tone in

smooth and striated muscle

(weakness, incoordination,

constipation, anorexia)

→TETANY- tingling sensations

(tip of fingers, around mouth),

spasm of muscles of

extremities/face.

→Trousseau’s sign- elicited by

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→Decreased DTR, decreased

bowel sounds and respi arrest

(sedates respi muscle)

→Late heart changes: decrease

pulse ad lead to cardiac arrest.

inflating BP cuff in upper arm-

causing carpal spasm: adducted

thumb, flexed wrist, extended

interphalangeal joints.

→Chvostek’s Sign- facial nerve is

tapped about 2cm anterior to

earlobe, result: twitching of

muscles of facial nerve.

→Increased irritability of CNS-

seizures, Dyspnea, mental

changes (depress, hallucination)

Diagnosis →Serum Ca (increased)

→X-ray (osteoporosis/ kidney

stones), ECG- arrythmias

→ECG: QRS complex widen,

prolonged ST interval, prolonged

QT interval.

Treatment 1. Pharmacologic

IV NaCl: dilute serum Ca

Furosemide (Lasix): diuresis w/

1. Acute symptomatic is life

threatening: Admin IV Ca

gluconate, Ca Chloride

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Ca excretion

Calcitonin- icrease bone

resorption and urinary Ca

excretion

-too rapid admin causes heart

arrest

-dagerous to pt having digitalis

derive meds

-inspect IV site for extravasation.

2. Vit D Therapy

Nursing

Management

1. Monitor ct at risk.

2. If pt takes Digoxin, assess for

toxicity. Encourage ambulation.

3. Take safety/seizure precaution.

4. Force fluid with high acid-ash

concentration (cranberry juice).

1. Severe Hypocalcemia: WOF

seizure precaution and monitor

airway.

2. Osteoporosis pt- health

teachings of food.

4. MAGNESIUM

Values >Normal Adult level: 1.3-2.1 mEq/L

Functions →acts directly @ myoneural junction

→present in bone, heart, nerves, and muscle tissues

→assist metabolism CHO & CHON, maintain electrical

activity in nerves and muscle. Acts like a sedative on

muscle.

Food Sources →vegetables, nuts, fish, peas, whole grains

→legumes, cocoa, peanut butter, seeds, seafoods

MAGNESIUM IMBALANCES

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HYPERMAGNESIMIA HYPOMAGNESIMIA

Value Magnesium level >2.1 Eq/L Less than 1.3 mEq/L

Causes •Renal Failure- kidney unable to

excrete Mg, Pt with untreated

DKA, Excessive antacid use, use

of laxatives and MOM.

• chronic alcoholism (most

common), diuretics, diarrhea, GI

losses and Meds (digitalis,

cisplatin)

Signs/

Symptoms

→ mild hyperMg: decreased BP,

N/V, weakness, facial flushing

→Increase Mg conc: lethargy,

difficulty speaking, drowsiness,

DTR lost, muscle weakness.

→if more than 10mEq/L=Respi

Depress.

(Increased Mg=Sedative)

→Neuromuscular changes:

hyperexcitability with muscle

weakness, tremor, tetany,

laryngeal stridor, muscular spasm

→cardiac changes: prolonged

QRS, depressed ST segment

→marked mood alterations

(Apathy, depression, agitation,

ataxia, insomnia)

→Hyperactive DTR

Diagnosis →Serum Mg (more than 2.5

mEq/L), Increased Potassium and

Ca are present concurrently

→ECG: Tall T-waves, widened

QRS, Prolonged PR interval.

→Serum elec (decreased Mg),

ECG, Urialysis

Treatment 1. Avoid admi of Mg to pt with RF.

2. Emergency: Respi distress-

ventilate pt, if heart conduction is

1. Mild Mg Def-Tx with diet alone

(oral admin of Mg salts)

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defective-give IV Ca gluconate.

2.Admin Loop diuretic (lasix) &

NaCl or LR (IV) to enhance Mg

excretion.

2. IVF: Mg Sulfate-Assess BP,

Heart ryhthm, Respi distress,

Notify MD if Urine output is less

than 100ml for 4hrs.

Nursing

Management

1. Monitor VS, noting pt

hypotension and shallow RR.

2.Assess for decrease patellar

reflexes and chage in LOC.

1. Monitor pt receiving digitalis.

2.If severe hypomagnesia-seizure

precaution.

3. Dysphagia is present-test

swallowing first before giving

water.

4.Assess DTR and give health

teaching on Diet.

4. PHOSPHORUS

Values >Normal Adult level: 2.5 to 4.5 mg/dl (had inverse

relationship with calcium).

Functions →essential for RBC and muscle function, formation of

ATP.

→assist with CHO,CHON, and fat met.

Food Sources →milk and mlik products, organ meats, nuts, fish, kidneys

→sardines, poultry, whole grains, dried fruits

PHOSPHORUS IMBALANCES

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HYPERPHOSPHATEMIA HYPOPHOSPHATEMIA

Value Phosphorus level >4.5 mg/dL Less than 3.0mg/dl

Causes •RF, Increased intake, decreased

output, chemo, DKA

•Admin of calories to pt with

severe protein-calorie malnutrition

•Malnourished pt

•Pain, heat stroke, prolonged

intense hyperventilation

•Alcohol withdrawal, hepatic

encephalopathy

Signs/

Symptoms

→ due from decreased Ca levels:

Tetany

→ATP def.-impairs cellular energy

resources (impairs Oxygen

delivery to tissue.

→Neurologic: fatigue, irritability,

weakness, paresthesia, confusion,

seizure, diplopia, dysphagia

→Hypoxia (Increased RR, Respi

alkalosis)

Diagnosis →Serum phosphorus, X-ray →Serum Elec, X-ray (bone

becomes brittle and weak)

Treatment 1. Treat underlying cause.

2.Admin Vit D prep (Calcitrol) to

increase Ca=decrease Phosphate

3. Admin Phosphate binding gels

1. Possible dangers of IV admin of

phosphorus include tetany from

hypocalcemia and calcifications

from tissue.

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(may lead to high Ca levels).

4. Restricted phosphorus diet.

2. Rate of IV should not exceed

10mEq/H

Nursing

Management

1. Avoid phosphate-containig

subs. (enema and laxative)

1. Assess for Hyper/Hypo

calcemia, and Health teaching on

diet.

IV. CONCEPT OF ACID-BASE BALANCE

•Power of Hydrogen: Normal pH range: 7.35-7.45

-the more Hydrogen ions=more acidic the solution=Lower pH

-the lower Hydrogen ions=more basic the solution=Higher pH

•Major Organs involved in regulating Acid-Base balance: Bones, Lungs and

Kidneys.

NOTE:

•Major LUNG chemical is= Carbon Dioxide

•Major KIDNEY chemicals are= Bicarbonate (HC03) and Hydrogen ion.

Respiratory Acidosis/ Alkalosis

>the problem is the Lungs.

Metabolic Acidosis/ Alkalosis

>Problem is the kidney.

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Hydrogen ion= Acid

Bicarbonate= Base

•If the Lungs are sick (retained too much

C02), the kidney compensates by

kicking HC03 into the blood and

excreting hydrogen ion out of the body.

•If lungs rids of too much C02

(Hyperventilation), the kidney

compensate by retaining Hydrogen Ion

and excreting HC03.

If the kidney malfunction, the Lungs will

compensate (quickly)- C02 is

excreted/retained.

1. BUFFER SYSTEM

Buffer occurs in response to changes in Acid-Base balance. Act by removing or

releasing Hydrogen ions (quickly).

•a. Carbonic Acid-Bicarbonate Buffering

•b. Protein Buffering

•c. Renal Buffering

NOTES:

→the only way CO2 can build up in the blood is significant decrease in respiration.

→the brain likes to the body pH to be perfect all the time. When pH gets out of

whack= Neuro and LOC can occur, therefore monitor them.

Arterial Blood Gas: Normal Values

pH Hydrogen ion concentration 7.35-7.45

PCO2 Partial pressure carbon dioxide 35-45mmHg

PO2 Partial pressure Oxygen 80-100mmGHg

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HCO3 Bicarbonate 22-26mEq/L

Metabolic Acidosis Metabolic Alkalosis

Concept →charac. by low pH and low

plasma HCO3 concentration.

pH: less than 7.35

HCO3 less than 22mEq/L

→charac. by high pH and

high plasma HCO3 conc.

pH: more than 7.45

HCO3 more than 26mEq/L

Causes →DKA, malnutrition, starvation

→Shock, kidney illness

→Diarrhea, ASA overdose

→Drugs (Diamox, Aldactone)

→vomiting; NG suctioning

→Excess antacid ingestion

→BT, NaHCO3 admin

→Drugs (Thiazide & Loop

diuretic), Baking soda,

HypoK, steroids.

Signs and

Symptoms

→hyperKalemia: if Hydrogen

ion builds up in

blood=Potassium goes out of

the cell. (Muscle twitching, oral

numbness, weakness)

→Kussmaul’s Breathing: Deep

and rapid-CO2 is blown off in

high amount.

→Early: Headache and lethargy

—late is Comatose.

→(related to decreased Ca)

→Tingling of fingers and toes,

dizziness, tetany

→Depress RR, HypoK

→ Hepatic Encephalopathy

(due to ammonia)

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→Chronic Renal Failure Pt

-chronic metabolic acidosis

(asymptomatic).

Diagnosis →ABG: pH less than 7.35;

HCO3 less than 22 mEq/L

PCO2 less than 35mmhg

(compensates)

→Serum elec (high potassium)

→ABG: pH more than 7.45;

HCO3 more than 26 mEq/L

PCO2 normal but increases

with compensation.

Medical

Management

1. Admin Sodium Bicarb (use

only in quick, temporary basis)

2. In chronic cases= treat first

low Ca serum.

1. Admin NaCl fluids.

2. Admin Ammonium Cl (IV)

3. Admin Acetazolamide

(Diamox).

Nursing

Management

1, Monitor ABG, HyperK,

Arryhthmia, HyperCa.

2. Closely monitor LOC.

3.Admin IVLR to increase base

level.

1. Monitor ABG, LOC, RR,

hypotension, DTR.

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Respiratory Acidosis Respiratory Alkalosis

Concept →due to inadequate CO2

excretion (Hypoventilation).

pH: less than 7.35

PCO2 more than 45mmhg

HYPERCAPNIA: build up of

CO2 in the blood to more than

45mmhg.

If PaCO2 is chronically more

than 50mmhg, the respi center

is insensitive to CO2 as respi

stimulant. Therefore Admin of

O2 may remove the stimulus of

→always caused by

hyperventilation.

pH: more than 7.45

PCO2 less than 35mmhg

HYPOCAPNIA: occurs when

CO2 is low; stimulates ANS

which causes: Anxiety,

tingling sensation and

sweating.

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Hypoxemia and pt develops

CO2 narcosis.

Causes →Respi arrest, Airway

Obstruction, Brain trauma

→Collapsed lung, weak respi

muscle, surgical incision

→sleep apnea, excessive

alcohol intake, narcotics,

sedatives

→Hysteria/ Anxiety

(Increased RR)

→ASA overdose; Pain; Fever

→Sepsis ,Anemia

Signs and

Symptoms

→Sudden: Increased RR Bp,&

PR, (Pt is breathing too shallow,

too slowly or nothing at all)

→Excess acid=Brain vasodilate

(Head fullness feeling, mental

cloudiness, Increased ICP,

brain swelling and decreased

DTR.)

→Acidic urine, Arrhythmias

Chronic Respi Acidosis

-present in pt with chronic

emphysema, bronchitis, &

obesity

→Vasoconstriction/

decreased cerebral blood flow

(inability to concentrate and

lightheadedness)

→Decreased Calcium

(numbness and tingling

sensation)

→Increased RR, rapid pulse

→ HypoK

Diagnosis →ABG: pH less than 7.35;

HCO3 normal until kidney

→ABG: pH more than 7.45;

HCO3 normal until kidney

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compensates

PCO2 more than 45mmhg

PO2 less than 80mmhg

compensates

PCO2 less than 35mmhg

Management (Goal: CT blow off excess CO2)

1. Treat the cause.

2. Airway Clearance.

3. Mechanical ventilation with

PEEP.

4. Admin Drugs to open airways

and thin out secretions.

5. Increase fluids; O2 Therapy;

Elevate HOB. Monitor ABG.

1. Treat the cause.

2. Monitor VS esp RR,

electrolytes, and ABG.

3. Calm the patient. Admin

anti-anxiety.

Have the client breath into a

paper bag/re-breather mask.

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IV. C O N C L U S I O N

Nurses need to understand the concepts of Fluid and Electrolyte/ Acid-Base

to anticipate, Identify, and respond to possible imbalances. An awareness of fluid

and electrolyte regulation guides the nurse in anticipating potential problems and

ensuring that appropriate interventions take place. Integral part for the nurse is to

identify/assess patient who are at risk in developing imbalances in fluids,

electrolytes, and acid-base. It’s a challenge for us to maintain their specific ranges

in normal values.

V. R E F E R E N C E S

→Understanding Pathophysiology, 3rd Edition (S. Huether & K. McCance)

→Brunner and Suddarth’s Textbook of MSN, 11th Edition

→Hurst Reviews (Pathophysiology Review)

→MSN made Incredibly easy, 3rd edition

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