M1 Acid Base Flashcards
Three mechanisms of regulating acid base balance
Buffering system
Respiratory compensation
Metabolic/renal compensation
Resp reguation of acid base 101
Lungs regulate CO2 that combines with H2O which forms H2CO3 - carbonic acid
H2 CO3
Carbonic acid
regulated by resp A/B system
What part of brain regulates Resp A/B balance
Medulla chemo receptors
Breathing faster/deeper - hyperventilation =
Breathing slower/shallower - hypoventilation =
CO2 elimination, increases pH
CO2 accumulation, decrease pH
Renal regulation of A/B balance
KIDNEYS key player
reabsorb or excrete acids or bases
can produce HCO3 bicarbonate
Carbonic acid
Bicarbonate
H2CO3 - acidic
HCO3 - basic
1 part carbonic acid =
20 parts bicarbonate
Kidney pH adjustments take ___ …
TIME
days to weeks
Normal Acid Base values
pH
PaCO2
HCO3
Pao2
Sao2
pH 7.35-7.45
PaCO2 45-35
HCO3 22-28
Pao2 80-100
Sao2 greater than %95
SpO2 -
Sao2 -
Pao2 -
SpO2 = oxygen saturation as measured by pulse oximeter
Sao2 = oxygen saturation as measured by blood analysis (e.g. a blood gas)
Pao2 = partial pressure of oxygen in the blood
ABG interpretation steps
classify pH
assess PaCO2
assess HCO3
determine compensation
total, partial, uncompensated
Respiratory acidosis
Decrease in rate of alveolar ventilation
pH less than 7.35
PaCO2 greater than 45mmHg
compensation = increase in HCO3
Respiratory acidosis causes
respiratory center depression
drug sedation/anesthesia
resp arrest
impaired ventilation/airway obstruction
Acidosis S/S CNS
Decrease in excitability
Drowsiness
Disorientation
Coma
restlessness
headache
Acidosis S/S cardiovascuar
Dysrhythmia
Decreased contractility
Hypotension
Resp alkalosis causes
Hypoxemia
Anemia
Fever
Dyspnea
Anger
S/S of alkalosis CNS/lytes/cardio
Increased excitability
numbness
tingling
confusion
blurred vision
Hypokalemia
Hypocalcemia
hypertension
Respiratory alkalosis renal compensation
HCO3 reabsorption drops
Metabolic acidosis 101
lab values
primary decrease in plasma bicarbonate
pH less than 7.35
HCO3 less than 22
Compensation = decrease in PaCO2
Metabolic acidosis causes
Loss of HCO3 - diarrhea
Decreased acid elimination - renal failure
Excess acid production -
Starvation
Diabetic/alcoholic ketoacidosis
Cardiac arrest
Sepsis
Shock
Metabolic alkalosis 101
lab values
Increase in bicarbonate in ECF (extracellular fluid)
pH greater than 7.45
HCO3 greater than 28
Compensatory increase in PaCO2
Metabolic alkalosis causes
Excess of base/loss of acid
Vomiting
GI suction
Alkali intake increase
med or diet
Furosemide diuretic
Methazolamide/acetazolamide and A/B balance
Carbonic anhydrase inhibitor
causes increase in metabolic acidity
Calcium carbonate antacids and A/B balance
Used to treat GERD
will lower pH
may result in metabolic alkalosis
Myasthenia gravis (MG)
Chronic autoimmune disorder
Antibodies destroy communication between nerves and muscle
Potassium and Acid Base Balance
Acidosis causes decreased K(+) secretion and increased reabsorption. SO, MORE K+
Alkalosis has the opposite effects, often leading to hypokalemia. SO, LESS K+
Increased anion gap indicates
Decreased anion gap indicates
Metabolic acidosis
Metabolic alkalosis
Normal anion gap range
8-12
Only thing the lungs control
CO2
Simple nursing intervention for hyperventilation
paperbag
CO2 is high
CO2 is low
Breathing slow and low, retaining
Breathing fast, blowing off
What is the anion gap
What does it represent
Values
Difference between all positively charged and negatively charged electrolytes
represents unmeasured phosphate sulfate and proteins that act as Acid Base buffers
8 to 12mEq/L
Reverse metabolic acidosis by giving
Sodium bicarbonate
When giving sodium bicarb to correct metabolic acidosis pt will become at risk of
why
cardiac arrest
potassium will shift back into cells resulting in hypokalemia
Diuretics like thiazide and furosemide can cause
This is due to
Metabolic alkalosis
Urination of lytes (potassium) and acids
Hypocalcemia symptoms
tingling in fingers/toes
dizziness
tetany
Why does metabolic alkalosis cause hypocalcemia
loss of H+ creates excess (-) ions, Ca++ binds to those and gets used up, creating hypocalcemia
Hypokalemia symptoms
heart palpitations
muscle weakness
prominent U waves
Why does metabolic alkalosis cause hypokalemia
Body holds on to H+ to correct issue.
Excess H+ replaces K+ and K+ gets excreted
This results in hypokalemia
Best way to narrow down cause of metabolic alkalosis
Urine chloride level
Carbonic anhydrase inhibitor med
MOA
Acetazolamide
enhance bicarbonate exertion
used for metabolic alkalosis
atelectasis
lung collapse
COPD causes
resp acidosis
When CO2 combines with water it becomes
Acidic
Acidic pt behavior =
alkalotic pt behavior =
lethargic
excitable
PT with Pulmonary embolism will first have resp alkalosis then acidosis why
first they hyperventilate due to panic, then the clot blocks off CO2 exchange sites
Only way to rid of CO2
exhalation
Can lungs fix them selves
NO, need kidneys to adjust
Kidneys control both
Hydrogen and bicarb
High anion gap =
accumulation of fixed acid
basic cause for metabolic acidosis
kidney failure
Atropine?
?
Do you even leave an unstable client?
NO, call rapid response.
do you ever push or mix potassium
NO
Common causes of metabolic acidosis
DKA
Renal Failure
Diarrhea
Resp acidosis S/S
confusion, disorientation, drop in LOC
Potassium and Resp Acidosis
Increase in K+
Treatment for resp acidosis
Oxygen vent or supplemental
bronchodilators, nebulizers
hydration
Respiratory acidosis and headaches
resp alkalosis and loc
Increase in CO2 dilates brain blood vessels
in resp alkalosis CO2 will drop which is why pt passes out
Resp alkalosis S/S
numbness
tingling
tinnitis
due to low calcium
loss of consciousness
Salicylate intoxication
causes which AB problem
Aspirin poisoning
Resp alkalosis
PaO2
normal range
Partial pressure or oxygen in arterial blood
How much PRESSURE oxygen exerts in blood
80-100mmHg
SaO2
Arterial oxygen SATURATION measured by pulse oximetry
95-100%
Allen test
Do PRIOR or taking blood gas
check radial and ulnar arterial flow before draw
In partial compensation, both CO2 and HCO3 levels are
Abnormal
In full compensation pH is
Normal
Biggest characteristics of ARDS
Ventilation problems
Refractory Hypoxemia
Surfactant
Liquid produced by alveoli to maintain function
No surfactant, no function
Most worrisome alarm on a ventilator
Low pressure
Drop in oxygenation
Basic assessment for ventilation
Auscultate all lobes for noise
If you cant fix the vent
Face mask pt and provide O2
Call for help
ARDS CXR will appear
White
ARDS ABGs will show a decrease in
O2 sat
Initial ABGs for ARDS will reveal resp
then
Alkalosis
Acidosis
FiO2
Fraction of inspired O2
Concentration of oxygen in gas mixture
room air is 21%
Best position for ARDS
Prone or up right
PEEP = _ = _
Vent = DECREASE IN CARDIAC OUTPUT
Due to ventilation and peep
Cardiac output will drop
this results in
Drop in BP
Drop in perfusion
Drop in urine output
Drop in LOC
Normal Cardiac output in L
4-6L/m
95% of all PE come from
Deep veins of legs
Different types of Thrombus
Blood clot
Lipid
Tumor
Amniotic sac (from baby)
Lipid thrombus is concern for first _h after long bone break
36
Other MAJOR site contributing to Thrombus development
Heart
A FIB specifically
If DVT suspected never do _ test
Homans
PLURAL FRICTION RUB =
Pulmonary Embolism
Cholesterol meds kill what organ
Liver
HIV tests
Elissa
Westernblot
PE can lead to right side heart failure T/F
True
D-dimers indicates only that
not
there is a clot
not a particular location
Best treatment for Hypoglycemia
DEXTROCE 50%
Anemia due to drop in kidney function
v in kidney function = _ = _
v in bone marrow = v in erythropoietin
Erythropoietin
Glycoprotein hormone
Produced by peritubular cells of kidney
Stimulates RBC production
v in RBC production can happen due to (GI)
Lack of iron
Lack of nutrition
Lack of erythropoietin
Livers major functions
4 of em
Detoxify body
Clotting
Metabolizes drugs
Synthesizes albumin
Aplastic anemia is also known as
Bone marrow aplasia
Aplastic anemia 101
body stops producing enough blood cells due to BONE MARROW damage
Aplastic anemia can happen due to
Birth defect
Poisoning - radiation, infection, medication
Diagnosing Aplastic anemia
Bone marrow biopsy
CBC
WBC
HnH
Treatment for aplastic anemia
Antithymocyte globulin ATG
Cyclosporins - immunosuppressant
Hemolytic anemia 101
RBC deformity
Intrinsic vs acquired hemolytic anemia
Something inside
Due to meds, treatment, developed condition
GI organ most impacted by CF
Pancreas
will become blocked and literally digest self
CF genome is autosomal
recessive
For tissue repair you need _ and _
Protein and Vit C
B1 =
B2 =
targets heart
targets lungs
1 heart 2 lungs
AKI = v in GFR =
HF = fluid overload =
Hyperkalemia
Hypokalemia
When not to give isotonic fluids
3 situations
HF
Renal failure
^BP
GFR numbers
90-100 idea
hospital wants greater than 60
Best Lab indicator of Renal Failure
Creatinine
Treating prerenal failure
Increase volume
give meds
Heart EF numbers
Want it to be greater than 50
less than 40 is HF
Mycin
vancomycin tobramycin S/S or toxicity
Ototoxicity
Nephrotoxicity
Peaks and trophs with mycin drugs
Check troph before giving
check peak 1h after
rhabdomyolysis 101
S/S
Kidney toxicity related to myoglobulin release from muscle injury
Dark urine (tea colored)
Glomerulonephritis big cause
moa
treat with
4 weeks after strep
PROTEINURIA
steroids
can bun and creatinine drop
NO
only normal or elevated
Big S/S of fat embolism
Petechia
NY Heart function classification
1-4
ok - worst
2-3lb increase in a week
HF
HF prevention BIGGEST MONITORING intervention
MONITOR WEIGHT DAILY
Right HF basic S/S
JVD
Liver pain
Clear breath sounds
Beta blockers block what system
what chemicals
Sympathetic
Epi Norepi
RAAS system most potent constrictor
converted at
ANGIOTENSIN II
Lungs
Nitro Directions
q5m for 3 doses
CALL EMS
B Blocker contraindications
COPD
Asthma
DIABETES - will mask symptoms
PT arrives at hospital
first 4 interventions
AONM
Aspirin
O2
Nitro
Morphine
Normal hematocrit
M
F
42-52
37-47
