Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Principles of Anesthesia I > E2 - Acid-Base Disorders > Flashcards

E2 - Acid-Base Disorders Flashcards

1
Q

In order to ensure optimal function of enzymatic function, acid-base balance is tightly regulated at what pH?

A
  • 7.35 to 7.45
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What causes acidemia?

A
  • Excess production of H+ (in relation to hydroxyl ions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What causes alkalemia?

A
  • Excess production of OH- (in relation to hydrogen ions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is known as the measured hydrogen concentration?

A
  • pH

The Power of Hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The stability of pH is managed by what three factors?

A
  • CO2 (enters/leaves the body via lungs)
  • HCO3 (enters/leaves the body via kidneys
    Via proximal tubule)
  • H+ (reabsorbed Via distal tubule and collecting duct)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the equation to calculate pH?

A

pH = 6.1 + log [serum bicarb/(0.03 x PaCO2)]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How can you tell if an acid-base disorder is a primary disorder with secondary compensation?
A. PaCO2 and HCO3 are equal
B. PaCO2 and HCO3 change in opposite direction
C. Both PaCO2 and HCO3 change in the same direction

A

C. Both PaCO2 and HCO3 change in the same direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How can you tell if an acid-base disorder is a mixed acid/base problem?
A. PaCO2 and HCO3 are equal
B. PaCO2 and HCO3 change in different direction
C. Both PaCO2 and HCO3 change in the same direction

A

B. PaCO2 and HCO3 change in different direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Acid/Base Disorder
pH: 7.34
PCO2: 48
HCO3: 24

A

Uncompensated Respiratory Acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the Acid/Base Disorder
pH: 7.58
PCO2: 38
HCO3: 29

A

Uncompensated Metabolic Alkalosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the Acid/Base Disorder
pH: 7.28
PCO2: 42
HCO3: 18

A

Uncompensated Metabolic Acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the Acid/Base Disorder
pH: 7.48
PCO2: 32
HCO3: 22

A

Uncompensated Respiratory Alkalosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

If your patient has normal lungs, what should their PaO2 be when they are on 60% FiO2?

A
  • PaO2: 240 to 300 mmHg

Normal range of PaO2: 80-100 mmHg
FiO2 of room air is 21%
FIO2 of 60% is about 3x of room air.
PaO2 will be between 240-300 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cardiovascular Consequences of Acidosis

A
  • Impaired contractility at pH 7.2
  • Decreased contractility
  • Decreased arterial blood pressure
  • Sensitive to re-entry dysrhythmias
  • Decrease threshold for V-fib
  • Decreased responsiveness to catecholamines at pH 7.1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nervous System Consequence of Acidosis

A
  • Obtundation
  • Coma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Pulmonary Consequences of Acidosis

A
  • Hyperventilation (d/t compensation, blowing off CO2)
  • Dyspnea
  • Respiratory Muscle Fatigue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Metabolism Consequence of Acidosis

A
  • Hyperkalemia (contributes to reentry dysrhythmias)
  • Insulin Resistance
  • Inhibition of anaerobic glycolysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define Respiratory Acidosis

A
  • An acute decrease in alveolar ventilation resulting in increase PaCO2
  • pH < 7.35
  • Caused by respiratory failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the causes of Respiratory Acidosis?

A
  • Drug-induced ventilatory depression
  • Permissive hypercapnia
  • Upper airway obstruction
  • Status asthmaticus
  • Restriction of ventilation (rib fx, flail chest)
  • Disorder of neuromuscular function
  • MH
  • PNA/ Pulmonary Edema, Pleural Effusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 causes of respiratory acidosis r/t anesthesia management?
A. excess bicarb administered
B. inadequate NMBD reversal
C. therapeutic hyperventilation
D. opioid excess
E. CO2 insufflation
F. consequence of pain

A

B. inadequate NMBD reversal
D. opioid excess
E. CO2 insufflation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the three categories that can cause Respiratory Acidosis?

A
  • Central ventilation control (neuro disorder/drug induced vent depression)
  • Peripheral ventilation control (neuromuscular disease)
  • VQ mismatch (Pneumonia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is a reason that a patient would have slow, shallow breathing ultimately leading to respiratory acidosis?
A. pneumothorax
B. atelectasis
C. sleep apnea
D. somnolence d/t residual opioids

A

D. somnolence d/t residual opioids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is a peripheral problem that would cause a patient to have rapid, shallow breathing ultimately leading to respiratory acidosis?
A. hemo/pneumothorax
B. bronchospasm
C. sleep apnea
D. residual opioid causing somnolence

A

A. hemo/pneumothorax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is a reason that a patient would have obstructed breathing ultimately leading to respiratory acidosis?
A. residual NM blockade
B. high spinal
C. bronchospasm
D. atelectasis

A

C. bronchospasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
In **acute** hypercarbia, if the PaCO2 increases by 10 mmHg, how much will the HCO3 increase for the system to be compensated? A. 3 mEq/L B. 10 mEq/L C. 1 mEq/L D. 5 mEq/L
C. for every 10 mmHg of PaCO2, bicarb should increase by **1 mEq/L** *10:1* in acute hypercarbia *10:3* in chronic hypercarbia ## Footnote *takes about 2-3 days for kidneys to increase bicarb levels in order to compensate*
26
In **chronic** hypercarbia, if the PaCO2 increases by 10 mmHg, how much will the HCO3 increase for the system to be compensated? A. 3 mEq/L B. 10 mEq/L C. 1 mEq/L D. 5 mEq/L
A. 3 mEq/L *10:3* in chronic hypercarbia *10:1* in acute hypercarbia ## Footnote This is prevalent in COPD patients
27
Upon arrival at the ICU, the patient has a PaCO2 of 80 mmHg. What is the expected HCO3 if this patient has compensated acute hypercapnia?
* 28 mEq/L Normal PaCO2 level: 40 mmHg Normal HCO3 level: 24 mEq/L PaCO2 of the patient is 80 mmHg PaCO2 increased by 40 mmHg For acute hypercapnia, ↑PaCO2 of 10 mmHg=↑HCO3- of 1 mEq
28
Upon arrival at the ICU, the patient has a PaCO2 of 80 mmHg. What is the expected HCO3 if this patient has compensated chronic hypercapnia?
* 36 mEq/L Normal PaCO2 level: 40 mmHg Normal HCO3 level: 24 mEq/L PaCO2 of the patient is 80 mmHg PaCO2 increased by 40 mmHg Chronic Hypercapnia: ↑PaCO2 10 mmHg=↑HCO3- 3 mEq HCO3- increase by 12 mEq/L Expected HCO3- = 24 + 12 = 36 mEq/L
29
What is the treatment for respiratory acidosis if hypercarbia is marked and CO2 narcosis is present? A. bolus some bicarb B. let them just breath off the CO2 C. sternal rub to make them hyperventilate D. mechanical ventilation
D. Mechanical Ventilation ## Footnote *plz*
30
What is the caution with reversing *chronic* hypercarbia with bicarb? A. Excessive bicarb will cause CNS irritability leading to seizures B. Excessive bicarb will cause more acidosis C. Excessive bicarb will cause metabolic alkalosis D. No caution: bolus that bicarb
A. Excessive bicarb will cause CNS irritability leading to seizures
31
Define Metabolic Acidosis.
a lowered blood pH signifying an **underlying condition** ## Footnote Metabolic Acidosis is secondary to an underlying disorder (*fix the problem to fix acidosis)*
32
How does the respiratory system fully compensate when someone is in metabolic acidosis? A. hyperventilating until pH gets back to normal range B. hypoventilating until pH gets back to normal range C. Respiratory compensation does not fully counter excessive acid production
C. Respiratory compensation does not fully counter excessive acid production
33
Metabolic Acidosis is associated with: select 2. A. alterations in transcellular ion pumps B. leftward shift of oxyHb dissociation curve C. increased ionized calcium D. decreased ionized calcium
A. alterations in transcellular ion pumps C. increased ionized calcium ## Footnote *and RIGHTward shift of oxyHb dissociation curve*
34
What direction will the Oxygen-Hemoglobin Dissociation Curve shift with Metabolic Acidosis?
Rightward Shift! Hb will have **decreased affinity** for O2 which allows *O2 to be released and available to the tissues*
35
What is your expected PaCO2 if your HCO3- is 12 mEq/L? A. 20 mmHg B. 22 mmHg C. 24 mmHg D. 26 mmHg
D. PaCO2 = 26 mmHg PaCO2 = (1.5 x HCO3-) + 8 = (1.5 x 12) + 8 = 26 mmHg ## Footnote *If PaCO2 is > 26 mmHg, compensation is INADEQUATE *
36
For every 1 mEq/L drop in base excess, PaCO2 should fall ______ mmHg.
For every 1 mEq/L drop in base excess, PaCO2 should fall **1.2 mmHg.** ## Footnote *Otherwise compensation inadequate!!*
37
What is the formula for determining the expected PaCO2 for someone in metabolic acidosis? A. PaCO2 = 1.5 x (HCO3- + 8) B. PaCO2 = (1.5 x HCO3-) + 8 C. PaCO2 = 1.5 + (HCO3- x 8) D. PaCO2 = (1.5 + HCO3-) x 8
B. PaCO2 = (1.5 x HCO3-) + 8 ## Footnote *KNOW THIS*
38
A normal anion gap __________. A. has a gain of chloride ions B. increases loss of bicarb C. maintains electrical neutrality D. has additional acids
C. maintains electrical neutrality *bicarb loss + chloride gain = neutral charges* ## Footnote *high anion gap has additional acids in extracellular space*
39
Bicarb loss is countered by the net gain of which ion? A. potassium B. sodium C. calcium D. chloride
D. Chloride ions ## Footnote *often called hyperchloremic acidosis*
40
Factors that cause metabolic acidosis with a normal anion gap.
* Sodium Chloride Infusion * Diarrhea * Early Renal Failure
41
What defines a high anion gap?
* Additional acid that is added to extracellular space * Acids dissociates into H+ that combine with bicarb to form carbonic acid that decrease available bicarb
42
Causes of high anion gap.
* Lactic Acidosis * Ketoacidosis * Renal Failure * Poisoning
43
What is the simple anion gap formula? What is the range of a simple anion gap?
* Sodium - (Chloride + Bicarb) * 12-14 mEq/L
44
What is the conventional anion gap formula? What is the range of a conventional anion gap?
* (Sodium + Potassium) - (Chloride + Bicarb) * 14-18 mEq/L
45
Anion Gap frequently ___________ (overestimates/underestimates) the extent of acid-base disturbances.
* Underestimates ## Footnote This is complicated by hypoalbuminemia and hypophosphatemia
46
How do you treat metabolic acidosis?
* Treat the cause!
47
Treatment for Metabolic Acidosis related to Ketoacidosis.
* Insulin and fluids
48
Treatment for Metabolic Acidosis related to Lactic Acidosis.
* Improve tissue perfusion
49
Treatment for Metabolic Acidosis related to Renal Failure.
* Dialysis
50
What are the parameters to treat metabolic acidosis with sodium bicarbonate?
* pH < 7.1 * HCO3- < 10 mEq/L
51
What are the negative effects of administering bicarb to someone with metabolic acidosis?
* Bicarb will react with H+ ion and generate CO2 which will diffuse intracellularly and decrease pH * In chronic metabolic acidosis, acute pH changes negate the right shift curve (Bohr effect) and cause tissue hypoxia ## Footnote The administration of IV NaHCO3 to treat metabolic acidosis should be reserved for the emergency treatment of select conditions
52
Formula for HCO3- Correction Dose
* Dose of Bicarb = 0.3 x Base Deficit x Wt (kg) ## Footnote Oftentimes, you would give half this dose and reassess
53
What happens to elective surgery if the patient experience acute metabolic acidosis?
* Surgery will be postponed
54
Anesthesia management considerations for urgent/emergent surgery with metabolic acidosis.
* Hemodynamic monitoring * Give Fluids * Monitor Cardiac Functions * Frequent Lab * Uphill battle, be honest with family members
55
Define Respiratory Alkalosis.
* An acute increased alveolar ventilation * Results in ↓ PaCO2 and pH > 7.45
56
What are the causes of Respiratory Alkalosis?
* Pregnancy * High Altitude (↑RR) * Salicylate overdose (asprin) * Iatrogenic hyperventilation (during perioperative period/ fear)
57
What are the symptoms of Respiratory Alkalosis?
* Decrease PaCO2 will cause vessel constriction * Lightheadedness * Visual disturbance * Dizziness
58
Respiratory Alkalosis will result in greater binding of calcium to ________.
* Albumin *Patient will be hypocalcemic.*
59
What are the signs and symptoms of hypocalcemia?
* Paresthesia, muscle spasm, cramp, tetany, circumoral numbness, seizures * Trousseau's sign * Chvostek's sign (Irritability on the facial nerve)
60
How many branches of the facial nerve are there? Name them :)
Five Branches: * Temporal * Zygomatic * Buccal * Mandibular * Cervical ## Footnote *Two Zebras Bit My Chicken*
61
Anesthesia management of respiratory alkalosis.
* Consider what is causing the hyperventilation (anxiety) * Consequence of Pain, Full Bladder, Agitation * Poor mechanical ventilation strategy * Therapeutic Hyperventilation
62
Define Metabolic Alkalosis.
* Marked increase in plasma bicarb usually compensated by an increase in CO2 * Renal or extrarenal causes * Net loss of H+ or a net gain of bicarb
63
What are other names for Metabolic Alkalosis?
* Volume depletion alkalosis * Volume overload alkalosis
64
What are the causes of Metabolic Alkalosis?
* Hypovolemia * Vomiting * NG suction * Diuretic Therapy * Bicarb administration * Hyperaldosteronism (Conn's ↑ Na+, ↓ K+)
65
Treatment for Metabolic Alkalosis?
* Treat the cause!
66
Treatment for Metabolic Alkalosis related to volume depletion.
* Saline fluid resuscitation
67
Treatment for Metabolic Alkalosis related to gastric loss.
* Proton Pump Inhibitors
68
Treatment for Metabolic Alkalosis related to loop diuretics.
* Potassium-sparing diuretics (Spironolactone)

Principles of Anesthesia I (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions