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Fluids / Electrolytes Principles of Homeostasis

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Case Scenarios 1/97 Water Fluids and Electrolytes Acid / Base Balances Brian E. Wheeler Will / Grundy EMS System Paramedic Education Program * * Fluids and ... – PowerPoint PPT presentation

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Title: Fluids / Electrolytes Principles of Homeostasis


1
Fluids / ElectrolytesPrinciples of Homeostasis
  • Silver Cross EMSS CME
  • October 2012 3rd Trimester

2
Our Agenda Today
  • System news!
  • Our main topic today Fluids and Electrolytes
  • CHF vs. COPD a quick but important refresher
  • (ALS) Strip O the Month PEA/Asystole

3
System News!
  • Please Press Take! For everything you remove
    from the Pyxis, you must press take. 5 IV
    catheters, 5 presses. 3 canulas, 3 presses.
    Etc. The supply people cant restock the machine
    properly otherwise and it leaves your fellow
    providers short of supplies.
  • IDPH fees and online process for license apps and
    renewals went into effect September 1st.

4
Body Systems Working Together
  • Integumentary
  • Skeletal
  • Muscular
  • Lymphatic
  • Respiratory
  • Digestive
  • Nervous
  • Endocrine
  • Cardiovascular
  • Renal / Urinary
  • Reproductive

5
Body Systems
  • Parceling out vital functions to several
    different organ systems results in
    interdependence of all body cells.
  • No individuals organ systems work in isolation.

6
Necessary Life Functions
  • Must be able to maintain their boundaries.
  • Internal environment must remain distinct from
    the external environment
  • Single cell organisms
  • Human beings

7
Necessary Life Functions
  • Movement
  • by muscles and the skeletal system
  • walking, running, writing
  • also other movement
  • blood moved through cardiovascular system
  • foodstuffs moved through digestive system
  • urine moved through urinary system
  • at the cellular level
  • the ability of cells to move by shortening
    (contractility)

8
Necessary Life Functions
  • Responsiveness
  • the ability to sense changes (stimulus) in the
    environment and respond to them
  • reflex - like touching a hot stove
  • carbon dioxide levels and respiratory rate

9
Necessary Life Functions
  • Digestion
  • the process of breaking down ingested foodstuffs
    to simple molecules that can be absorbed into the
    blood.
  • Nutrient rich blood is then distributed to all
    areas of the body
  • Amoeba
  • a single celled digestion factory

10
Necessary Life Functions
  • Metabolism
  • a broad term that includes all chemical reactions
    which occur within body cells
  • catabolism breaking down
  • anabolism building up
  • all catabolism all anabolism equals metabolism

11
Necessary Life Functions
  • Excretion
  • the process of removing wastes from the organism
  • get rid of non-useful substances
  • toxins

12
Necessary Life Functions
  • Reproduction
  • cellular
  • cell division
  • Mitosis and meiosis
  • organism
  • eggs and sperm

13
Necessary Life Functions
  • Growth
  • increase in size of a body part or the organism
  • usually the result of an increase in the number
    of cells
  • may be due to increased size of existing cells
  • in any case it is the result constructive
    activities occurring at a rate faster than
    destructive activities

14
Survival/Physiological Needs
  • nutrients
  • oxygen
  • water
  • normal body temperature
  • atmospheric pressure

15
The body has a natural tendency to keep the
internal environment constant.
Temperature Water Sugar Blood
Volume Oxygen Carbon Dioxide Heart
Rate Respiratory rate Blood Pressure
HOMEOSTASIS
16
Homeostasis
  • Greek for like fixed conditions
  • Walter Bradford Cannon (1871-1945) established
    our basic understanding about the global function
    of the adrenal gland/sympathetic nervous system
    axis

17
Homeostatic Control Mechanisms
  • Variable
  • Receptor/affector
  • Control center
  • Brain
  • Effector
  • Negative feedback
  • furnace thermostat
  • Positive feedback
  • bleeding
  • delivery
  • hormone balance

18
Negative Feedback Loop
  • A stimulus produces a response that opposes the
    original stimulus
  • Thermostat controls heating/cooling
  • When the room temperature rises/falls, the
    thermostat (control center) triggers an EFFECTOR
    response that restores normal temperature
  • Can be either to warm up or to cool off

19
Brains Negative Feedback Loop
  • The brain is the control center for regulation of
    body temperature
  • Receptor-sensors in skin/cells of
    thermoregulatory center (affector pathway) sense
    temperature outside the normal acceptable range

20
Brains Negative Feedback Loop
  • The brain sends a command, via EFFECTOR pathways
    for the skin and sweat glands to react and
    balance the heat in the body to regain
    homeostasis

21
Positive Feedback Loop
  • Initial stimulus produces a response that
    reinforces a stimulus
  • EX thermostat wired so when temperature is low,
    the heater turns on rather than the air
    conditioning
  • Initial stimulus (decreased heat/temp) causes
    response (heater on) and heat stimulus
    strengthened instead of cooled

22
Thermoregulation
  • If the thermoregulation center in the brain is
    unable to function, the body would die from
    either hyperthermia or hypothermia

23
Homeostatic Control Mechanisms
  • Antagonist
  • blocks a physiological response
  • reverses or opposes
  • -olytic
  • Agonist
  • causes a physiological response
  • -mimetic

24
FLUIDS
25
Water
  • Water is an essential medium which forms the
    chief environment in which cells live and
    function
  • Transport medium for nutrients, hormones, blood
    cells and waste products
  • Regulates body temperature

26
Some additional quick terminology...
intra
cellular
within
pertaining to cells
extra
vascular
outside of
pertains to vessels
27
Hyper-
Hypo-
high / increased
low / decreased
heme, hema, hemo
blood
-carbia
carbon dioxide
28
WATER
  • Most abundant substance in the human body
  • 60 of total body weight
  • Fluid Compartments
  • Intracellular
  • Extracellular
  • intravascular
  • interstitial

75
25
7.5
17.5
29
Fluid compartments of the body.
30
Intracellular Fluid (ICF)
  • Basic unit of organ structure
  • Contains nucleus, mitochondria, endoplasmic
    reticulum and lysosomes

31
Extracellular Fluid (ECF)
  • Water that surrounds the cell/outside the cell
  • Interstitial fluid bathes cells
  • Intravascular fluid plasma portion of blood
    found in circulatory system/in the vessel.
  • Plasma carries RBC, WBC, platelets, electrolytes,
    hormones, waste, etc.

32
Water Intake
  • How do we get it into our bodies?
  • Well of course drinking water and other fluids.
  • From eating fruits and vegetables
  • Oxidative metabolism

33
Water Intake
  • But also by eating foods not typically thought of
    as containing a great deal of water
  • Actual fluids 1640cc/day
  • Food 750 cc/day
  • Oxidative metab. 350 cc/day
  • TOTAL 2,740 cc/day

34
Water Output
  • All the water excreted from the body as urine but
    also
  • Water excreted including the lungs, skin and
    intestines

35
Sources of OUTPUT
How much intake fluid is required?
  • Urine 1700 cc
  • GI tract 150 cc
  • Sweat 150 cc
  • Vapor in resp. 400 cc 2400 cc

Insensible losses
HOMEOSTASIS
36
Monitoring Water Balance
  • Daily weight
  • 1 kg (2.2lbs) means a fluid loss or gain of 1
    liter of fluid
  • Takes 3,000 ml of ECF deficit to produce signs of
    dehydration (4 of total body wt.)

37
Abnormal decrease in total body water
  • Insensible losses (saliva, sweating,
    respirations)
  • such as from fever states
  • Sweating
  • Internal losses (Third Spacing)
  • Plasma losses (Burns, surgical drains, fistulae)
  • Gastrointestinal losses (diarrhea, vomit)
  • Implies loss of electrolytes (increased metabolic
    rate)

38
Signs and Symptoms
  • Dry mucus membranes
  • Thirst
  • Poor skin turgor
  • Tachycardia
  • Hypotension
  • In infants, sunken fontanel, lack of tears, fewer
    diaper changes
  • Dark urine
  • Orthostatic hypotension
  • Absence of normal sweating
  • Hematocrit elevated in pure
  • dehydration, may be decreased if
  • actively bleeding
  • Increased respiratory rate
  • Confusion, Coma, Death
  • Decreased urinary output

DEHYDRATION
39
Treatment
  • ALS/ILS
  • Get fluid in
  • IV isotonic solution
  • Well get to this part later!

DEHYDRATION
40
An excess of total body water
  • May aggravate Congestive Heart Failure
  • Chronic overhydration can cause renal failure

The major sign of over-hydration is EDEMA.
OVERHYDRATION
41
Signs and Symptoms
  • Hypertension may indicate overload
  • Jugular Vein Distention (JVD)
  • Tachycardia
  • Dependent edema / crackles
  • Hematocrit decreased
  • Shortness of Breath
  • Headaches, confusion, coma, seizures

OVERHYDRATION
42
Treatment
  • GET THE WATER OFF!
  • How would you do this as a paramedic?
  • How does the body do this on its own?

OVERHYDRATION
43
Kidney Function
  • Regulates blood volume/blood pressure
  • Adjusts volume of H2O lost in urine
  • Regulates hormones erythropoietin renin release
  • Regulates concentration of plasma ions of Na,
    K, Cl- by controlling amount lost in urine
  • Controls blood pH by controlling loss of H ions
    and HCO3- ions concentrated in urine

44
(No Transcript)
45
Production of Urine
  • Blood flows through the glomerulus
  • Glomerular pressure pushes fluid out of the
    glomerular capillaries and into the Bowmans
    capsule at the rate of 180 L / day
  • Peritubular capillaries reabsorb water, glucose,
    sodium and other nutrients and put it back in the
    general circulation
  • Peritubular capillaries also secrete hydrogen
    ions, potassium ions and ammonia

46
Urine Regulation
  • Aldosterone
  • ADH
  • Atrial natiuretic factor hormone
  • Prostaglandins and kinins

47
Aldosterone
  • hormone secreted by the adrenal gland
  • stimulates tubules to reabsorb sodium salts to
    attract and hold water

48
ANTIDIURETIC HORMONE (ADH)
  • Secreted in the posterior pituitary gland
  • osomoreceptors are stimulated by an increase in
    the osmolality of body fluids
  • atrial receptors are stimulated by a fall in
    venous blood volume
  • makes distal and collecting tubules permeable to
    water, thus increasing water reabsorption
  • water is therefore retained in the presence of ADH

49
Increased ADH production
  • high plasma osmolality compared to interstitial
    fluid
  • low circulating volume sensed by baroreceptors
  • stimulation of sympathetic nervous system
  • Drugs-- morphine, oxytocin, diabinase
  • head injuries, meningitis - syndrome of
    inappropriate ADH Secretion

50
Decreased ADH production
  • Decreased production of ADH results from--
  • Decreased plasma osmolatity
  • Increased circulating volume
  • Alcohol consumption
  • Caffeine
  • Cold

51
Atrial Natiuretic Factor/PeptideANP
  • Secreted from cells in the right atrium of the
    heart when pressure in the right atrium increases
  • ANF inhibits ADH secretion and reduces the
    ability of the kidney to concentrate urine

52
Prostaglandins Kinins
  • Formed in the kidneys
  • Promote vasoconstriction and increased capillary
    permeability
  • Part of the inflammatory process
  • Influence the rate of filtrate formation and
    sodium ion reabsorption

53
Cant you make it any easier?
  • Kidneys have two options--
  • Retain water, put it back in the intravascular
    space.
  • -or-
  • Dump (water) urine into the urinary bladder

54
Administration of Diuretic Therapy
  • Furosemide (Lasix)
  • inhibits sodium and chloride reabsorption by the
    loop of Henle
  • also causes venous dilation
  • used primarily for acute pulmonary edema CHF

55
Furosemide (Lasix)
  • Contraindicated in pregnancy
  • Precautions
  • dehydration
  • electrolyte depletion (hypo-kalemia)
  • contributing to digitalis toxicity
  • Side effects
  • hypotension
  • ECG changes
  • chest pain
  • electrolyte deficiencies
  • Dosage
  • 20-40 mg IVP (at medical control discretion)

56
ELECTROLYTES
  • Related to 5 physiologic processes
  • Water distribution
  • Osmotic pressure
  • Neuromuscular activity
  • Acid/Base Balance
  • Support of cellular metabolism

57
Electrolytes
  • Chemical substances (ions) that dissociate
    charged particles when placed in water and are
    usually measured in milliequivalents (mEq/L).

58
ELECTROLYTES
  • The Endocrine system and the kidneys are the
    primary way of regulating fluids and
    electrolytes.
  • Osmoreceptors in the hypothalamus monitor fluid
    concentrations.
  • Hypothalamus secretes ADH
  • ADH stored in the Posterior pituitary gland
  • Kidneys release Renin which in turn controls
    release of Aldosterone
  • Aldosterone helps controls pH, electrolyte and
    fluid balance

59
ELECTROLYTES
Anions have a negative charge
Cations have a positive charge
60
ESSENTIAL CATIONS
  • SODIUM (Na)
  • Prevalent in the extracellular fluid
  • Normal range is 135-145 mEq/L
  • Helps regulate distribution of water
  • Helps transmit nerve impulses

Na
Na
Na
Na
Na
Na
Na
Na
Na
Na
Na
Na
Cell
Na
Na
Na
Na
Na
Na
Na
Na
Na
Na
Na
61
Sodium (Na)
  • Changes in concentration stimulate pituitary
    gland to secrete or withhold ADH
  • Electrolyte of ventricular depolarization

62
Sodium (Na)
  • Kidneys are the chief regulator of Na
  • Moves rapidly between vascular and interstitial
    spaces
  • Rapid movement of water (in and out of cell)
    causes concentration of Na to change quickly,
    even though Na does not cross cell wall
    membranes easily

63
Hyponatremia
  • Water retention
  • ECF becomes hypotonic to the cell and water
    shifts into ICF. This causes ? blood volume and a
    large portion of the body fluid in the cell
    pitting edema
  • Osmolality ? r/t ? Na resulting in fluid
    (osmosis) movement from ECF to ICF

64
Hyponatremia
  • vomiting and diarrhea
  • 3rd space losses of ECF from peritonitis,
    ascites, ileus
  • CHF, peripheral edema
  • Excessive use of oral water intake
  • When crackles/rales are present volume is ? at
    least 1500 ml from normal

65
Hyponatremia
  • Signs and symptoms
  • Mental confusion, delusions
  • ? blood volume, ? BP, tachycardia
  • Muscle weakness, abdominal cramping
  • Flat neck veins
  • Flushed skin, increased body temperature
  • Headache
  • Dry mucous membranes

66
Hyponatremia
  • Treatment
  • IV normal saline (isotonic) for dehydration
  • Diuretics for CHF with Na deficit
  • What are some of the common diuretics patients
    take?

67
Hypernatremia
  • Sodium excess, water loss without salt loss
  • What happens?
  • ECF becomes hypertonic and water shifts from ICF
    to ECF until equal

68
Hypernatremia
  • Decreased intake of fluids, especially in hot
    weather
  • Febrile states, increased sweating
  • Copious watery diarrhea
  • Salt H2O retention related to inability to
    excrete Na r/t starvation, severe illness,
    dehydration

69
Hypernatremia
  • Sodium reabsorption from steroid use
  • ? capillary permeability during inflammation or
    allergic process
  • ? plasma proteins in nephrosis or cirrhosis or
    from renal failure

70
Hypernatremia
  • Results from burns, excessive sweating and DKA
    (diabetic ketoacidosis/hyperglycemia
  • Hypothyroidism, Cushings Syndrome and toxemia
    during pregnancy

71
Hypernatremia
  • Drugs that ? Na levels
  • Diuretics
  • Heparin
  • NSAIDS
  • antidepressants
  • Drugs that ? Na levels
  • Steroids
  • Antibiotics
  • Cough meds
  • Laxatives
  • Oral contraceptives

72
Hypernatremia
  • Treatment
  • Sodium restriction
  • diuretics

73
ESSENTIAL CATIONS
  • Potassium (K)
  • Prevalent in the intracellular fluid (ICF)
  • Key role in the transmission of electrical
    impulses/cell excitability

Extracellular
Intracellular
K
K
Na
Na
K
K
K
K
74
Potassium (K)
  • Normal range 3.5 5.2 mEq/L
  • Renal failure causes K to not be flushed out
    normally causing toxicity
  • K continually moves in and out of cells
  • Entrance into cell depends on normal metabolism
    and utilization of glucose

75
Hyperkalemia
  • Renal failure, burns
  • Tissue trauma, massive crush injuries
  • Excessive K intake
  • Respiratory/metabolic acidosis
  • When tubules excrete H ions to ? pH levels, K
    accumulates in the blood

76
Hyperkalemia
  • Signs/symptoms
  • Muscle weakness, irritability
  • Nausea, diarrhea
  • Intestinal colic, muscle cramp pain
  • EKG changes
  • Wide QRS, peaked T wave, depressed S-T segments,
    no P wave, cardiac arrest/asystole

77
Hyperkalemia
  • Treatment
  • Elimination of K intake
  • IV infusion of normal saline in large volume
  • CaCl- IV to antagonize K affects on myocardium
  • Glucose and insulin to drive K into cells

78
Hypokalemia
  • K deficit caused by excessive loss of K
  • Metabolic alkalosis
  • Diuretic therapy
  • Acute alcoholism
  • Uncontrolled diabetes
  • Excessive perspiration

79
Hypokalemia
  • Signs/symptoms
  • Apathy, lethargy, muscle weakness
  • Tachycardia
  • Abdominal distention/gas
  • Weak pulse
  • DIB, shallow respirations
  • Metal depression
  • EKG flat T wave, depressed ST segment, VF

80
Hypokalemia
  • Treatment
  • KCl- (potassium chloride)
  • IV lactated ringers

81
Potassium (K)
  • Drugs that ? levels
  • Diuretics
  • Laxatives
  • ASA
  • Drugs that ? levels
  • Heparin
  • Epinephrine
  • Mannitol
  • Histamines

82
ESSENTIAL CATIONS
  • Calcium (Ca)
  • Plays major role in muscle contraction
  • Plays major role in nerve impulse transmission
  • Assists with Na and K crossing cell membrane

Extracellular
K
Na
Ca
Intracellular
83
Calcium Ca
  • Normal range 9.0-10.5 mg/dl
  • Helps to coagulate blood
  • Maintains normal heart depolarization of the SA
    and AV nodes
  • Maintains plasma membrane permeability

84
Calcium (Ca)
  • Gate to allow Na to enter into cell for
    depolarization (contraction) to occur. Increased
    levels of Ca block this gate, leading to
    decreased cell permeability and depressed
    peripheral nervous system

85
Calcium (Ca)
  • Regulated in the bone, intestine and kidney
  • Parathyroid hormone (PTH) and vitamin D maintains
    levels of Ca. PTH is released in response to
    low Ca and renal tubules and intestine reabsorb
    Ca through Vitamin D

86
Hypercalcemia
  • Increased Ca absorption
  • Prevention of renal excretion
  • Hypercalcemia which decreases cell membrane
    permeability resulting in decreased
    neuro-muscular excitability

87
Hypercalcemia
  • Renal disease
  • Excessive ingestion of milk or Vit. D
  • Prolonged immobilization bed rest
  • Bone cancer (Ca is released from the bone in
    large amounts)
  • hyperthyroidism

88
Hypercalcemia
  • Signs and symptoms
  • Fatigue, depression

89
Hypocalcemia
  • Massive infections, peritonitis, pancreatitis
  • Chronic renal failure
  • Burns
  • Hypothyroidism

90
Hypocalcemia
  • Signs/symptoms
  • Muscle cramps
  • Muscular excitability, twitching, tetany
  • Signs of malnutrition, chronic alcoholism
  • Anxiety
  • Increased GI motility (N,V,D)
  • Laryngeal spasms, hypoxia
  • EKG prolonged QT interval
  • Decreased BP
  • Hyperventilation, increased respirations

91
Testing for Hypocalcemia
  • Just for fun, dont try this!!
  • Trousseaus Sign Place BP cuff on arm and
    inflate to exceed systolic pressure for 3
    minutes. Note carpal spasm with contraction of
    thumb and fingers. Note inability to open the
    hand.
  • Hyperexcitaility is due to decreased Ca that is
    enhanced by the ischemia
  • THIS IS ONLY A POTENTIAL TEST.DO NOT DO THIS IN
    THE FIELD

92
Hypocalcemia
  • Treatment
  • IV fluids, normal saline
  • Calcium gluconate, CaCl- or Vitamin D
  • To reverse hyperventilation (alkalosis), have
    patient rebreathe CO2

93
ESSENTIAL CATIONS
  • Magnesium (Mg)
  • Necessary for
  • several biochemical processes, neuromuscular
    transmission/excitability, metabolism of carbs
    and proteins

94
Magnesium (Mg)
  • Normal range 1.2 2.0 mEq/L
  • Intracellular cation that is bound to ATP energy
    and found mostly in bone (67) and muscle (20)
  • Modifies enzyme activity
  • Found in legumes, grains, green veggies, meat
    seafood

95
Magnesium (Mg)
  • Essential for glycolysis which is necessary for
    ATP production
  • Activates the Na/K ATPase pump
  • More on this in cardiology!!

96
Magnesium (Mg)
  • Therapeutic effects
  • Bronchodilating properties for acute asthma
  • Stops seizure activity in eclampsia
  • Treat alcoholism withdrawal
  • Treats tachycardia in digoxin toxicity
  • Acute MI for increased resuscitation outcome
    (pts generally have low levels)

97
Hypermagnesemia
  • Very rare
  • Chronic renal failure
  • Laxative/cathartic abuse
  • Antacids, maalox, pepto, milk of magnesia

98
Hypermagnesemia
  • Signs/symptoms
  • Respiratory depression
  • Lethargy, confusion,
  • GI r/t nausea and vomiting
  • Uncontrolled diabetes
  • EKG short QT interval, prolonged PR and QRS
    intervals, bradycardia and heart blocks

99
Hypermagnesemia
  • Treatment
  • Control diabetes and GI loss
  • Treat cardiac dysrhythmias
  • Administer Ca
  • dialysis

100
Hypomagnesemia
  • Decreased dietary intake, alcoholism
  • Fistulas
  • GI disorders
  • AMI, post CABG
  • DKA due to diuresis
  • Decreased K

101
Hypomagnesemia
  • Signs/symptoms
  • Weakness, irritability
  • Tremors, tetany
  • Vertigo, seizures
  • HTN, hx of AMI
  • Increased systemic vascular resistance
    (tachycardia)
  • Insulin resistance

102
Hypomagnesemia
  • Treatment
  • Administer Magnesium Sulfate (MgSO4)

103
Magnesium
  • Drugs that ? levels
  • Antacids
  • Thyroid meds
  • Antibiotics
  • diuretics
  • Drugs that ? levels
  • Insulin
  • antibiotics

104
ESSENTIAL ANIONS
  • Chloride (Cl-)
  • Balances the positive charge associated with the
    cations
  • Plays major role in fluid balance and renal
    function by maintaining osmotic pressure
  • Close association with sodium

105
Chloride (Cl-)
  • Normal range 90-110 mEq/L
  • Extracellular anion
  • Combines with H ions to produce hydrochloric
    acid to aid in acid/base balance

106
Hyperchloremia
  • Dehydration
  • Eclampsia
  • Metabolic acidosis, respiratory alkalosis
  • hyperthyroidism

107
Hyperchloremia
  • Signs/symptoms
  • Lethargy, weakness
  • Deep respirations
  • Kussmauls respirations
  • Decreased cognition

108
Hypochloremia
  • Overdhydration
  • CHF
  • Burns
  • Metabolic alkalosis, respiratory acidosis
  • burns

109
Hypochloremia
  • Signs/symptoms
  • Shallow respirations
  • Decreased BP
  • Tetany, hyperexcitability

110
Chloride
  • Drugs that ? levels
  • Cortisone
  • Estrogen
  • Anti-inflammatory
  • Drugs that ? levels
  • Bicarbonate
  • diuretics

111
ESSENTIAL ANIONS
  • Bicarbonate (HCO3- )
  • Principle Ion of the Buffering System
  • Controlling pH levels of the body
  • ECF

112
Bicarbonate (HCO-3)
  • Normal range 135-145 mEq/L
  • Intracellular
  • Renal component of acid/base balance
  • Binds H ions to form carbonic acid in the
    process of buffering metabolic acidosis caused by
    anaerobic metabolism and lactic acid production

113
Bicarbonate
  • Carbonic acid rapidly crosses into cells causing
    a worsening of intracellular hypercarbia (too
    much carbon) and acidosis which depresses
    myocardial and cerebral function
  • Bicarbonate crosses into cells more slowly

114
Sodium Bicarbonate
  • Medical indications for NaHCO3
  • Late in cardiac arrest after defib, CPR, ET,
    oxygenation/ventilation and at least 2
    administrations of epinephrine
  • Overdose with tricyclic antidepressants (binds
    Na channels)
  • Alkalinize urine in drug overdoses

115
Sodium Bicarbonate
  • Effects of administration
  • Fluid retention (cardiovascular)
  • Tissue necrosis at IV site (skin)
  • Can cause metabolic alkalosis (electrolyte)

116
Sodium Bicarbonate
  • IMPORTANT NOTE
  • Do not mix NaHCO3- with calcium agents as it will
    precipitate
  • Monitor for fluid overload
  • Crackles
  • Pink, frothy sputum
  • Peripheral edema

117
Fluid and Electrolyte Imbalance
  • There comes a point where the body (especially
    the kidney) can no longer maintain
    interrelationships of fluids and electrolytes
    essential to normal function resulting in
    imbalance
  • Your job is to prevent further imbalance by
    recognizing the s/s AND knowing what therapy to
    administer

118
Problems with Fluids and Electrolytes
  • Result from
  • Volume disturbance (too much/too little)
  • Irregularities in transportation of fluid (CHF,
    shock)
  • Ratio of fluid and electrolytes imbalanced
    (acidosis, alkalosis)
  • Shifts of fluid to the wrong places
    (edema/ascites)

119
SEMIPERMEABLE MEMBRANES
  • Cell membrane which allows passage of certain
    substances and restricts the passage of others.
  • Allows
  • Oxygen, Carbon Dioxide, Water
  • Restricts
  • Proteins, Glucose

120
Only capillaries have walls thin enough to let
solutes pass through.
121
Colloids vs. Crystalloids
  • Colloids
  • Contains proteins or high molecular weight
    (large) molecules
  • salt-poor albumin, dextran
  • Crystalloids
  • Primary compounds used in pre-hospital
  • Lactated Ringers, Normal Saline, D5W

122
COLLOID SOLUTIONS
  • Advantages
  • Requires less solution to replace vascular volume
  • Maintains colloid oncotic pressures
  • Effective as volume expanders
  • Disadvantages
  • More expensive
  • Pulmonary complications
  • Allergic reactions
  • Interference with platelet function
  • Renal complications

123
CRYSTALLOIDS
  • Advantages
  • Inexpensive
  • Readily available
  • Causes no allergic reactions
  • No infectious disease transmission
  • Effective volume expanders
  • Cleared by lymphatics
  • Disadvantages
  • Need large amounts of solution to replace
    vascular volume
  • 3 to 1 ratio -adult
  • 20 cc/kg peds

124
Were going to be especially interested in three
spaces.
Where do we put fluid?
Intracellular space
Interstitial space
Intravascular space
Via intravenous catheters
125
TONICITY
(Concentration of molecules)
  • ISO Same
  • Hyper More
  • Hypo Less

tonic
Number of molecules
tonic
tonic
126
Tonicity
  • The degree of concentration (osmolarity) of a
    solution depends on the amount of solutes
    (particles) dissolved in water
  • Tonicity controls movement of water across the
    membrane

127
Tonicity
Cell
Interstitial
128
Isotonic (Iso means same right?)
Cell
Interstitial
129
TONICITY
  • HYPERTONIC -- A state where a solution has a
    higher solute concentration on one side of a
    semipermeable membrane compared to the other side.

Cell
Interstitial
Intravascular
130
Cell
Interstitial
131
TONICITY
  • HYPOTONIC -- A state where a solution has a lower
    solute concentration on one side of a
    semipermeable membrane compared to the other side.

Cell
Interstitial
Intravascular
132
Cell
Interstitial
133
Hypotonic Hypertonic
Cell
Interstitial
134
What is the tonicity of these?
Cell
Interstitial
135
?
?
Cell
Interstitial
136
Water and Electrolyte Distribution
  • One of the forces that govern the movement of
    water/electrolytes is passive transport
  • Passive transport moves substances down their
    concentration gradient through the appropriate
    transport proteins

137
Passive Transport
  • Osmosis
  • Diffusion
  • Facilitated Diffusion
  • PASSIVE TRANSPORT MEANS NO ATP ENERGY IS
    REQUIRED FOR MOVEMENT
  • Ex fish that swim with the current

138
OSMOSIS The movement of water across a
semipermeable membrane from an area of relatively
lower solute concentration to an area of
relatively higher solute concentration.
Cell
Interstitial
139
Osmosis
  • Water moves along the concentration gradient from
    an area of low solute concentration to an area of
    high solute concentration to achieve equilibrium
  • The force that makes the water move is called the
    osmotic pressure

140
Osmosis
141
Osmotic Pressure
  • The amount of pressure required to stop osmosis
    and water moving across the semipermeable membrane

142
Osmosis
  • How are patients affected by osmosis?
  • Increased ICP due to cerebral edema
  • Give manitol as a hypertonic solution as the
    particles will pull water
  • Diabetic ketoacidosis (DKA)
  • Increased glucose make plasma hypertonic to
    interstitial fluid
  • Fluid moves from interstitial space to vascular
    space

143
Osmosis
  • How are patients affected by osmosis?
  • Can experience dehydration acidosis
  • Give infusions of normal saline (isotonic) to
    dilute the plasma and rehydrate interstitial
    compartment

144
DIFFUSION The movement of solutes across a
semipermeable membrane from an area of relatively
greater solute concentration to an area of
relatively lower solute concentration.
Cell
Interstitial
145
Diffusion
  • Spontaneous process that distributes molecules
  • Molecules continually are in motion and collide.
    The collisions cause molecules to change
    direction and spread out until they are uniformly
    distributed

146
Diffusion
  • Move down the concentration gradient because they
    diffuse from regions of higher concentration to
    lower concentration
  • Solutes move more slowly than water
  • Ex O2 and CO2 in the lungs

147
And now for something Completely Different!
  • Lets take a few minute break, then come back.

148
CHF vs. COPD
  • We are seeing a lot of this in narratives lately
  • Patient exhibiting difficulty breathing with
    wheezes. Patient given Albuterol via nebulizer,
    no change in condition.

149
CHF vs. COPD
  • Then as we read further, we see information like
    this
  • Patients BP 160/100. Patient hx CHF/pulmonary
    edema/left-side heart failure. Patient EKG
    atrial fibrillation. Patient meds lasix,
    Cardizem, coumadin.

150
RED FLAGS!!!
  • History of CHF/pulmonary edema and/or afib
  • High blood pressure
  • Trouble breathing
  • Noisy lungs

151
Consider CHF!
  • Red flags indicate high suspicion for CHF, NOT
    COPD
  • Nebulized albuterol is not going to help.
  • Will just raise heart rate and work heart further
  • Might help a tiny bit if the patient has
    co-morbid COPD or asthma, but not much
  • You can always throw an in-line neb on the CPAP
    if you suspect a bit of COPD too.

152
But remember CHF is not a respiratory issue
  • Congestive heart failure and pulmonary edema are
    cardiac issues.
  • Need a cardiac solution
  • Your go-tos
  • CPAP
  • Nitro
  • Lasix and Morphine with medical control approval
  • CPAP and nitro are miracle-workers in CHF!

153
Then why do we hear wheezing?
  • In the field, occasionally hard to differentiate
    between wheezes and crackles/rales.
  • Wheezes are musical
  • More common during expiratory phase
  • Crackles, well, crackle (and pop and click and
    bubble)
  • More common during inspiratory phase

154
Online!
  • If you have a moment, Google lung sounds. Its a
    great way to learn the difference!
  • An example of a good lung sound site
  • http//www.stethographics.com/main/physiology_ls_i
    ntroduction.html

155
Strip O the Month
  • Asystole/PEA

156
Asystole (Cardiac Standstill)
  • Asystole is a total absence of ventricular
    electrical activity
  • There is no ventricular rate or rhythm, no pulse,
    and no cardiac output
  • Some atrial electrical activity may be evident
  • P-wave asystole

157
Asystole ECG Characteristics
158
Asystole Causes
  • Pulmonary embolism
  • Acidosis
  • Tension pneumothorax
  • Cardiac tamponade
  • Hypovolemia
  • Hypoxia
  • Heat/cold (hypothermia/hyperthermia)
  • Hypokalemia/hyperkalemia (and other electrolytes)
  • Myocardial infarction
  • Drug overdose/accidents (cyclic antidepressants,
    calcium channel blockers, beta-blockers, digoxin)

PATCH-4-MD
PATCH-4 MD
159
Asystole Intervention
  • Confirm the absence of a pulse
  • Perform immediate CPR
  • Confirm the rhythm in two leads
  • Consider possible causes of the rhythm
  • Pharm Epinephrine 110,000 1mg IV/IO
  • No More Atropine!!!

160
Pulseless Electrical Activity (PEA)
  • Pulseless electrical activity is a clinical
    situation, not a specific dysrhythmia
  • Formerly called electromechanical dissociation
    (EMD)

161
Pulseless Electrical Activity
  • PEA exists when organized electrical activity
    (other than VT) is present on the cardiac
    monitor, but the patient is pulseless

162
PEA Causes
  • Pulmonary embolism
  • Acidosis
  • Tension pneumothorax
  • Cardiac tamponade
  • Hypovolemia (most common cause)
  • Hypoxia
  • Heat/cold (hypothermia/hyperthermia)
  • Hypokalemia/hyperkalemia (and other electrolytes)
  • Myocardial infarction
  • Drug overdose/accidents (cyclic antidepressants,
    calcium channel blockers, beta-blockers, digoxin)

PATCH-4-MD
163
PEA Intervention
  • Begin CPR
  • Search aggressively for possible cause(s) of the
    situation
  • Often finding the right H or T can solve PEA
    quickly
  • Most common cause hypovolemia
  • Pharm Epinephrine 110,000 IV/IO
  • No More Atropine!!!

164
  • Questions?
  • If you are watching live, type into text box.
  • Otherwise, feel free to email afinkel_at_silvercross.
    org or call 815-300-7425
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