ABGs

Question 1

Normal pH

Answer 1

7.35-7.45

Question 2

Normal PaCO2

Answer 2

35-45
- resp parameter

Question 3

Normal HCO3

Answer 3

24-29
- metabolic parameter
- calc on the ABG OR on a chem panel as a serum CO2

Question 3

Primary event

Answer 3

What causes the A/B imbalance
- hypovent, hypervent, vom

Question 4

Primary disorder

Answer 4

What results from the primary event
- resp acidosis, met acidosis, etc

Question 5

Metabolic imbalance

Answer 5

Problem of bicarb and kidneys
- chx in H+ or bicarb ions

Question 6

Arterial blood gas labs

Answer 6

• pH (7.35-7.45)
• PaCO2 (partial pressure of CO2 in artery)
• HCO3 (calculated value)

Question 7

Venous blood gas values

Answer 7

• pH (7.31-7.41)
• PvCO2 (partial pressure of CO2 in vein)–41-51
• HCO3 (calculated value)

Question 8

Basic metabolic panel (BMP) aka chem panel labs

Answer 8

Serum CO2 = HCO3 level (24-29)

Question 9

Respiratory imbalance

Answer 9

• H2CO3 changes secondary to resp alterations (lungs)
• resp problem in nature
• inc/dec in CO2
• change in ventilation

Question 10

ROME

Answer 10

Respiratory Opposite, Metabolic Equal

Question 11

Metabolic alkalosis

Answer 11

• too much bicarb or not enough carbonic acid
• pH inc, PaCO2 neutral, HCO3 inc
• excess intake of bicarb or alka seltzer, prolonged vom, NG suction, diuretics
• causes hypokalemia causing H+ to shift out the ICF and K into cell

Question 12

Metabolic alkalosis CM

Answer 12

• CNS over-excitability
• Confusion
• Tremors
• Muscle cramps
• Paresthesias:
• tingling of fingers and toes,
  perioral
• Coma
• N/V/D
• Resp depression

Question 13

Respiratory alkalosis

Answer 13

H2CO3 deficit in ECF
- caused by hyperventilation like anxiety attack, inc metabolic demand like sepsis, meds, hypoxia, PE or lung disease, CNS lesions, ventilator, head injury
- pH inc, PaCO2 dec, HCO3 neutral

Question 14

Respiratory alkalosis CM

Answer 14

• CNS over-excitability
• Tachypnea
• Light headedness
• Confusion, blurred vison
• Paresthsia -Numbness of hands and
  feet, perioral
• Hyperactive reflexes, seizures
• Coma

Question 15

Tx for respiratory alkalosis

Answer 15

Nonrebreather, dec RR, calm pt

Question 16

Respiratory acidosis

Answer 16

• excess H2CO3 (excess H+)
• hypoventilation, OD, not breathing enough, anesthesia, narcotics, head injury, pain, pulmonary dx, liver fail, airway obs

Question 17

What would you not do to tx resp acidosis?

Answer 17

sodium bicarb; instead, ventilate

Question 18

Respiratory acidosis CM

Answer 18

• hypoventilation
• dyspnea
• respiratory distress
• shallow respirations
• H/A, restlessness,
  confusion
• tachycardia,
  arrhythmias
• LOC, stupor, coma

Question 19

Acute vs chronic resp acidosis labs

Answer 19

Acute: pH dec, PaCO2 inc, HCO3 neutral
Chronic: pH neutral, HCO3 inc

Question 20

Metabolic acidosis

Answer 20

• HCO3 deficit in ECF (excess acids added or bicarb lost)
• pH dec, PaCO2 neutral, HCO3 dec
• Caused by fistulas, renal failure, DM, DKA type 1, lactic acidosis, prolonged diarrhea (relative inc acid d/t dec HCO3), starvation (ketosis), shock, cardiac arrest

Question 21

Metabolic acidosis CM

Answer 21

• CNS
• Lethargy, drowsiness
• Confusion
• Tremors, muscle cramps
• Paresthesias:
• Tingling of fingers or toes,
  perioral
• Hypotension
• Hyperkalemia
• Deep breathing
• Kussmaul respirations (DKA)
• Fruity Odor Breath (DKA)

Question 22

Steps of interpreting ABGs

Answer 22

1. Acid or base problem
2. Look at CO2 (if opp, resp prob)
3. Look at bicarb
4. Look at compensation

Question 23

If uncompensated…

Answer 23

pH is normal

Question 24

If partially compensated…

Answer 24

pH is abnormal, both other numbers are abnormal

Question 25

If compensated, pH…

Answer 25

Is normal but others are abnormal

Question 26

If corrected…

Answer 26

All normal; doesn’t always occur (COPD)