Acid/Base

Question 1

Allen’s test

Answer 1

before an arterial blood gas test, looks at indicators for acid/base imbalance

Question 2

Hydrogen Ions (H+)

Answer 2

vital to life

expressed as pH

pH of 7 is neutral, small is acidic

low concentration in body

circulate as carbonic acid (H2CO3) = (CO2+H2O) (fixed)
(governed by lungs)

circulate has nonvolatile for of hydrogen and organic acids (governed by kidneys)

Question 3

Acids

Answer 3

Produced as end products of metabolism

create muscle aches (build up of lactic acid - anaerobic glycolysis)

Contain H+ ions (lower pH scale)

Strength of acid determined by # of H+ ions

Fewer H+ = weaker acid, or form weak base

Lungs to bulk of work in acid /base balance, kidneys fine tune

RR increase, removal of metabolic acids (CO2)

Question 4

Bases

Answer 4

Contain NO H+ ions at all, but they accept H+ ions from acids: will neutralize or decrease strength of the base or form weak acid

HCO3- Bicarb is most important base

Question 5

pH and Acids in the blood

Answer 5

Blood pH 7.34-7.45

reflects H+ ion concentration, greater concentration, the lower the pH, the more acidic the blood

the lower the H+ the higher the pH and the more alkalotic the blood

Acids form from metabolic activity (Duh)

Question 6

Regulation on Blood pH: Blood Buffers

Answer 6

Buffer: A weak acid/base that can combine with strong acid/base to minimize changes in pH

goal: to try and fix what the body sense is wrong, keep blood pH in normal range

MAJOR buffer systems:
(Intracellular)
-Potassium-Hydrogen ion exchange (in and out of cell)

/\ H+ > H+ moves into cells & K+ moves out
\/ H+ > H+ moves out of cells & K+ moves in

(Extracellular)
Protein buffers, hgb (80%)
Albumin and plasma globulins (20%)

Bicarbonate buffer: most important

phosphate buffer: 2nd most

bone buffer

Question 7

Buffers: Regulatory systems for H+ concentration in blood

Answer 7

Fast acting

immediate protection against changes in H+ ion concentration

Function to keep pH within narrow limits of stability

Absorb or release H+ as needed

transport to carry H+ ions to lungs

Once primary buffer systems react, they are consumed, body less able to manage correcting pH in blood. so MORE stress, less of ability to compensate.

Question 8

Intracellular buffer system: Potassium

Answer 8

Alkalosis: cells release H+ ions into blood to increase acidity of blood and combat alkalosis. K moving into cell and the K level goes down

Blood: HIGH H+, HIGH pH

End result: Normal pH (bc HIGH H+) but low serum K level

Acidosis: body protects itself from acid state by moving H+ ions into the cell and K moves out to make room for H+ ions. H+ and the K level goes up

Blood: HIGH H+ and LOW pH

End Result: LOW H+ , Normal pH, HIGH serum K

Question 9

Major buffer systems: Extracellular Fluid

Answer 9

Hemoglobin System* (80% of extracellular buffer system)

• in RBCs
• maintains acid/base balance
• Chloride exchange with Bicarbonate*** in response to level of O2 in the blood

for each Chloride ion that leave, a Bicarb enters and visa versa

Anion exchange for Anion

Low pH, more acidic: Bicarb OUT, Cl IN = low serum chloride aka HYPOCHLOREMIA

High pH, more basic: Bicarb IN, Cl OUT = high serum chloride aka HYPERCHLOREMIA

Question 10

Plasma Proteins system and Calcium example

Answer 10

Albumin/ Globulins - responsible for wound healing, oncotic pressure

functions with LIVER (made in liver) can vary H+ ions in protein

ex: Total calcium, unbound calcium, bound calcium

UNBOUND = Ionized calcium (metabolic active) can give s/s but bound cannot give s/s bc not metabolic active

Low Ca is lower threshold for firing nerves, tingling

Question 11

Phosphate buffer system

Answer 11

Present in cells and body fluids

especially active in kidneys

(acts like bicarb) clears spare H+ Ions in order to bring pH to normal range

Question 12

Major Buffer system: Carbonic acid / Bicarbonate system

Answer 12

Carbonic acid: IN THE LUNGS

its the only acid the lungs can breathe out (Co2) and water (H20)

Bicarbonate system: KIDNEYS

whole system maintains pH of 7.4 with

20:1 ratio
bicarb:carbonic acid
(when ratio out of sync - buffer systems kick in)

Carbonic acid concentration controlled by excretion of Co2 by lungs, RR will change to control this

Bicarbonate concentration selectively retain or secrete bicarb in response to body needs

DKA - produces ketoacids, deplete bicarb and make more carboinc acid, this increases RR and give kusmal respirations

Question 13

Carbonic Anhydrase

Answer 13

Carbonic acid dissociates with help of enzyme Carbonic Anhydrase

HIGH acid: HIGH RR and Depth

BASE: LOW RR and low depth

Carbonic acid is volatile bc it is in gas form (continual buffer regulation required in lungs)

Question 14

Lungs

Answer 14

2nd defense (1st blood buffer) with respirations and depth rate

Alkalosis: pH goes up, and RR and depth go DOWN, to neutralize excess bicarb

in Acidosis: pH goes down and RR and depth go UP to blow off acids

Question 15

Activation of Lungs

Answer 15

reversible in controlling excess or deficit

take 10-30 seconds to occur (really fast)

Question 16

Kidneys

Answer 16

Final correction of Acid/Base disturbances. Rental excretion of acids and alkali occur more slowly

takes hours or days

in acidosis: pH goes down and excess H+ secreted into tubules and combine with buffers for excretion in urine

in alkaosis: pH is UP and bicarb ions move into tubules combine with Na and are excreted into urine

Question 17

Renal excretion of Acid

Answer 17

selective regulation of bicarb in kidneys: 3 ways

• kidney restore bicarb by release of H+ ion and holding bicarb
• extra H+ ions excreted in urine AS phosphoric acid
• alteration of amino acids in renal tubules, and diffuses into ammonia and is excreted in urine

takes HOURS to DAYS

end result is fine tuning we need

Question 18

Ratio of buffer system

Answer 18

Fixed ratio of HCO3 (base) to H2CO3 (acid) 20:1

increase base: 30:1
result: HIGH blood pH, alkalosis

decrease base: 13:1
result: LOW blood pH, acidosis

Question 19

BMP*

Answer 19

Basic Metabolic Panel

**CO2 from VENOUS blood is actually a measure of HCO3 (Bicarb) **

High value = alkalosis
low value = acidosis

Question 20

Metabolic Acidosis

Answer 20

Total concentration of buffer base is lower than normal with a relative increase in H+ concentration

occurs as a result of losing too many bases and holding too many acids without sufficient bases

lose base with severe diarrhea

gain acid with DKA

Question 21

Causes: Metabolic Acidocis

Answer 21

DKA (#1 reason) - can be life threatening. Not enough insulin, glucose builds up in system (not in cell) so cell function goes to fat metabolism, ketones build up, makes person acidotic. Bicarb becomes exhausted, increase RR and depth

Renal insufficiency/ Failure:
results from the inability of kidneys to metabolize proteins and remove acids as a result of protein metabolism. Bicarb cannot sustain. PT needs to be on dialysis.

Carbohydrates: not enough O2 for proper burning of Carbs, glucose and water. Lactic acid builds up, lactic acid acidosis

Question 22

Causes: Metabolic Acidocis Pt II

Answer 22

Excessive ingestion of Aspirin:
causes increase in H+ concentration

Severe Diarrhea: loss of base leads to acidosis.

Malnutrition: improper nutrients causes fat catabolism leading to build of up ketones and acids

High Fat diet: too much rapid accumulation of waste products leading to ketone and acids (Ex: Atkins Diet)

Question 23

Anion Gap

Answer 23

Lab that describes concentration of unmeasured anions

only look at for metabolic acidosis. Do they have too much acid or loss of base

elevation results from accumulation of acids (unmeasured anions of acids)

LOW AG result from:
Low in unmeasured anion or
High in unmeasured cation

Question 24

High Anion gap vs Low Anion Gap

only applicable with acidosis

Answer 24

HIGH:
high acids
excessive production of metabolic acids
-DKA, starvation, Alcoholic intoxication
-Aspirin poisoning , rental Failure

NORMAL: 
low bicarb, low base
loss of intestinal secretions
diarrhea, pancreatic fistulas
- renal losses, tubular acidosis
-HYPOaldosteronism 
-increased CL levels

Question 25

Assessment of metabolic acidosis

Answer 25

In attempt to blow off extra CO2 and compensate for acidosis, hyperpnea and Kussmaul respirations (high RR and depth) headache, vomiting, diarrhea, fruity smelling breath, twitching, mental dullness**, drowsiness, stupor, coma, convulsions

Question 26

Manifestations of metabolic acidosis

Answer 26

Neutral: weakness, lethargy, malaise, confusion, stupor, coma cardio: decrease HR, dysrhythmias, vasodilation GI: Anorexia, abdominal pain Skeletal: Bone disease Skin: Flushed warm dry COMPENSATION: RR and depth INCREASE (Kussmaul) Hyperkalemia Acid Urine: increase in ammonium in urine

Question 27

intervention of metabolic acidosis

Answer 27

determine cause maintain airway asses LOC for CNS depression Monitor electrolytes maintain I&O, assist with fluids safety for confusion and coma administer IV, isotonic saline, 5% dextrose ect monitor K carefully

Question 28

intervention of metabolic acidosis PT II

Answer 28

In DKA - GIK mechanism - insulin given so K can go into cell with K. Decreases ketoacidosis monitor for circulatory collapse, moving lots of fluids. make sure they have enough fluid to maintain BP in Renal failure: dialysis may be sued to remove protein and waste products. maintain better diet to lessen acidosis.

Question 29

metabolic acidosis treatment

Answer 29

monitor patients at risk (DM, sepsis, shock) ``` monitor BP and RR monitor ABGs Monitor K+ levels Administer sodium bicarbonate cardiac monitor for low serum K+ levels ``` correct underlying cause of acidosis administer IV fluids with lactase for lactic acidosis: IV fluids and O2 for renal fluid, drug OD or poisoning: Dialysis Chronic: Increase Carbs and decrease Fat

Question 30

Metabolic Alkalosis

Answer 30

Kidneys deficit of carbonic acid and decrease in hydrogen ion concentration results from accumulation base or loss of acid without a comparable loss of base in body fluids pH>7.45

Question 31

Metabolic Alkalosis Causes

Answer 31

Malfunction of metabolism, leading to increased amount of basic solution in the blood and decrease in available acids in blood Can happen with: Ingestion of excess sodium bicarbonate (more base in blood) THAT LEADS TO Excessive vomiting (leads to loss of acids)

Question 32

Metabolic Alkalosis Causes Pt. II

Answer 32

Also gastrointestinal suctioning: most common cause IN HOSPITALS Diuretics - wash out Hydrogen and potassium ions. Increases Bicarb Hyperaldosteronism - increases tubular sodium reabsorption, Hydrogen ions leave Massive blood transfusion - Citrate anticoagulant used for storage of blood is metabolized to bicarb

Question 33

Metabolic Alkalosis Etiologies

Answer 33

Excess gain on bicarb (alka-seltzer) TPN - for ppl who cannot maintain nutritional status orally. Has acetate, not good solutions with lactate, or citrate NaHCO3 in CPR Loss of acid, increased bicarb vomiting, bulimia potassium deficit volume contraction (loss of fluids, diuretic therapy) mechanical ventilation, respiratory acidosis

Question 34

Metabolic Alkalosis Assessment

Answer 34

In an attempt to compensate, RR and depth go down to conserve CO2 ``` nausea vomiting diarrhea numbness and tingling restlessness and twitching hypokalemia hypocalcemia sinus tachycardia dysrhythmias ```

Question 35

Metabolic Alkalosis Manifestation

Answer 35

Neural: association with hypocalcemia confusion convulsion paraesthesia Cardio: hypotension dysrhythmias Compensation: RR and depth decrease urine ph increase

Question 36

Metabolic Alkalosis Treatment

Answer 36

Monitor patients at risk (GI fluid loss) Monitor Vs (respiration rate and depth) correct underlying cause supply Cl to enable renal reabsorption of NaCl MONITOR CARDIAC for hypocalcemia Teach: new method for indigestion

Question 37

Respiratory Acidosis

Answer 37

lower pH and High PaCO2 Too much acid, too little base total concentration of buffer base is lower than normal, but increased Hydrogen concentration due to defective function in the lungs or changes in normal respiratory patterns due to secondary problems anything that obstructs airway can cause respiratory acidosis

Question 38

Respiratory Acidosis Causes

Answer 38

Hypoventilation - not breathing effectively (ex. drug OD) Co2 is retained and H ions increase leading to acid state. carbonic acid is retained and Ph goes down can cause infection dude to inflammation and bacterial agents. Airways can become obstructed meds: sedatives, narcotics, anesthetics depress respiratory center lead to hypoventilation

Question 39

Respiratory Acidosis Causes pt II

Answer 39

Pneumonia - secretions obstruct airway passages, limits gas exchange (common cause) Atelectasis - excessive mucus production , infection drainage, collapse of alveolar sacs, decreased respiration Brain trauma - too much pressure of respiratory center of brain emphysema - part of COPD, loss of avelolar sacs, more energy to breathe in and out, increased Co2 Asthma, Bronchitis, Pulmonary Edema, Bronchiectasis

Question 40

Respiratory Acidosis Etiologies

Answer 40

``` Acute** VERY TROUBLESOME lung disease acute pulmonary edema aspiration atelectasis pneumothorax pneumonia depression of respiration center narcotic OD head injury ``` ``` Chronic conditions: Chronic bronchitis Asthma cystic fibrosis COPD ``` ``` Chest wall and respiratory muscles: Obesity post op pain abdominal ro thoracic incisions Abdominal distention (bowel obstruction) ```

Question 41

Respiratory Acidosis Assessment

Answer 41

``` in attempt to compensate, RR and depth increase** headache mental status change confusion drowsiness restless visual disturbances diaphoresis cyanosis hyperkalemia rapid and irregular pulse, dysrhythmias ```

Question 42

Respiratory Acidosis Manifestations

Answer 42

``` Neural: Dilation of cerebral vessels fullhead headache behavior changes confusion depression paranoia tremors paralysis stupor coma ``` SKIN: warm and flushed Head is tachy Respiratory: dyspnea and cyanosis Compensation: Acid Urine

Question 43

Respiratory Acidosis Interventions

Answer 43

``` Maintain airway improve ventilation administer o2 semi-fowlers turn, cough, breath deep hydrate suction if necessary TCDB - turn cough deep breath ``` NEVER USE SEDATIVE

Question 44

Respiratory Alkalosis

Answer 44

pH is high, Co2 is low (hyperventilation - panic attack) deficit of carbonic acid and decrease in hydrogen ion concentration results from accumulation of base or from loss of acid without a comparable loss of base in the body fluids

Question 45

Respiratory Alkalosis Cause

Answer 45

conditions that cause over stimulation of respiratory system (hyperventilation - panic attack) blowing off too much co2 Hysteria - often neurogenic in nature, can lead to vigorous breathing Over ventilation by mechanical ventilators ( ventilated TOO quickly)

Question 46

Respiratory Alkalosis Causes Pt II

Answer 46

condition that increase metabolism Pain or brain trauma Salicylates - aspirin poisoning , causes hyperventilation Hypoxia - causes respiratory stimulation with result of carbonic acid deficit

Question 47

Respiratory Alkalosis Etiologies

Answer 47

``` Excessive ventilation anxiety hypoxemia high fever Excessive mechanical vent (same as causes) ``` Pregnancy (increased sensitivity to Co2)

Question 48

Respiratory Alkalosis assessment

Answer 48

initial hyperventilation and respiratory stimulation will cause abnormal rapid respiration***RR and depth go down to compensate ``` headache Mental status changes vertigo lightheaded paresthesias hypokalemia hypocalcemia tetany convulsions ```

Question 49

Respiratory Alkalosis Manifestations

Answer 49

``` cerebral vasoconstriction (head fog) ``` neuromuscular irritability - hypocalcemia - electrolyte imbalances cardio: dysrhythmias hyperventilation GI epigastric pain

Question 50

Respiratory Alkalosis

Answer 50

``` manage anxiety maintain airway control breathing rebreather mask monitor monitor electrolyte values emotional support ``` administer calcium gluconate for tetany if necessary

Question 51

Obtaining an Arterial Blood Gas Specimen

Answer 51

``` get Vs determine if they have arterial line do allens test asses factors impacting results prepare heparinized syringe emotion support pressure to puncture for 5 min label specimen and put on ice document ``` COPD is different - careful bc the co2 sensors are worn out, respond to low o2, so giving o2 can shut down respiratory system

Question 52

Major forms of acid/base imbalances

Answer 52

primary imbalance: acute condition or chronic condition cause of the problem compensated imbalances: respiratory compensated by renal system** metabolic compensated by the respiratory** combined imbalance: both respiratory and metabolic both acidic or basic, both of everything

Question 53

Analyzing blood gas resutls

Answer 53

1. look at ph (up -alkolosis, down -acidosis) 2. look at PCO2, 3. look at bicarb (does it correspond with pH? if so, metabolic imbalance) 4. remember compensation has occurred is ph is in normal range, if not , look at respiratory and metabolic indicators)

Question 54

Acid base imbalances summary

Answer 54

Respiratory acidosis: In respiratory acidosis, the pH is down In respiratory acidosis, the PCO2 is up Respiratory alkalosis In respiratory alkalosis, the pH is up In respiratory alkalosis, the PCO2 is down ---------------------- Metabolic acidosis: In metabolic acidosis, the pH is down In metabolic acidosis, the HCO3 is down Metabolic alkalosis: In metabolic alkalosis, the pH is up In metabolic alkalosis, the HCO3 is up

Question 55

Compensation: pH within normal limits

Answer 55

Respiratory acidosis & respiratory alkalosis: When compensation has occurred, the pH will be within normal limits The blood gas result reflects partial compensation if the HCO3 is abnormal The blood gas result reflects an uncompensated condition if the HCO3 is normal ______________- Metabolic acidosis & alkalosis: When compensation has occurred, the pH will be within normal limits The blood gas result reflects partial compensation if the PCO2 is abnormal The blood gas result reflects an uncompensated