Critical Care

Question 1

What is compliance?

Answer 1

Change in volume divided by change in pressure

Question 2

What is CPP (cerebral perfusion pressure)? Normal values?

Answer 2

MAP - ICP

>70 mm Hg

Question 3

What is the substrate for lactate?

Answer 3

Pyruvate

Anaerobic pathway: pyruvate –> lactate by lactate dehydrogenase

Question 4

Fate of lactate

Answer 4

Converted into glucose in the liver (or kidney) via Cori cycle

Question 5

What is base deficit?

Answer 5

Indirect measurement of acidosis on ABG

Question 6

What is weakness of base deficit as an end point of resuscitation?

Answer 6

Nonspecific.

Resuscitation with normal saline causes hyperchloremic acidosis.

Question 7

What is currently the best end point of resuscitation?

Answer 7

Lactate

Question 8

Normal I:E ratio?

Answer 8

1:2

Question 9

What is RSBI?

Answer 9

RR/TV

>105 means likely to fail extubation

Question 10

Treatment of auto-PEEP?

Answer 10

Decrease RR
Decrease TV
Increase expiratory time

Question 11

Causes of hypoxia?

Answer 11

1. Decreased inspired oxygen
2. V/Q mismatch
3. Shunt
4. Decrease in barometric pressure (increased altitude)
5. Diffusion (pulmonary edema or ARDS)
6. Hypoventilation (airway obstruction)

Question 12

Three determinants of oxygen delivery?

Answer 12

1. CO
2. Hgb
3. O2 saturation of Hgb (SaO2)

Question 13

Why does giving too much blood decrease oxygen delivery?

Answer 13

Increases viscosity of blood

Question 14

What is the best marker of ventilation?

Answer 14

PaCO2 (on ABG)

Question 15

What 2 barriers constitute the alveolar-capillary barrier?

Answer 15

1. Microvascular endothelium

2. Alveolar epithelium

Question 16

What is the pathogenesis of the early acute phase of ARDS?

Answer 16

Breakdown of the alveolar-capillary barrier and accumulation of transudate fluid (protein filled) in the alveolar air sac

Question 17

Diagnostic definition of ARDS?

Answer 17

1. Timing - less than 1 week after insult
2. CXR - bilateral infiltrates
3. Noncardiogenic edema
4. P/F ratio < 300

Question 18

Mild, moderate, severe ARDS p/f?

Answer 18

200-300 = mild
100-200 = moderate
<100 = severe

Question 19

Acetazolamide MOA (carbonic anhydrase inhibitor)?

Answer 19

Diuretic
Removes bicarbonate in the urine
Use in metabolic alkalosis

Question 20

Milrinone MOA?

Answer 20

PDE III inhibitor
decreases breakdown of cAMP => increases intracellular levels of cAMP and calcium
positive inotrope
decreases afterload (SVR)
no net increase in myocardial oxygen consumption

Question 21

Isoproterenol MOA?

Answer 21

Beta 1 and 2 agonist
positive inotrope
increases HR (chronotropy)

Question 22

Esmolol MOA?

Answer 22

Beta adrenergic antagonist
short half life = 9 min
easily titrated

Question 23

Narcotic OD tx?

Answer 23

Narcan

Question 24

Benzo OD tx?

Answer 24

Flumazenil

Question 25

Calcium channel blocker OD tx?

Answer 25

Calcium

Question 26

Malignant hyperthermia tx?

Answer 26

Dantrolene

Question 27

Heparin reversal tx?

Answer 27

Protamine

Question 28

Phenergan-induced dystonia tx?

Answer 28

Benadryl

Question 29

Tylenol OD tx?

Answer 29

Acetylcysteine

Question 30

Beta-blocker OD tx?

Answer 30

Glucagon

Question 31

Brown recluse spider bite tx?

Answer 31

Dapsone

Question 32

Hydrofluoric acid burn tx?

Answer 32

Calcium gluconate

Question 33

Cyanide toxicity from burn inhalation injury?

Answer 33

1. Sodium nitrate | 2. Sodium thiosulfate

Question 34

What should tidal volume and plateau pressures be in patient with ARDS?

Answer 34

Tidal volume 4-6 mL/kg | Plateau pressures < 35

Question 35

Who needs ppx for UGIB in the ICU?

Answer 35

1. Patients intubated > 48 hr 2. Coagulopathic patients 3. Burn patients 4. Brain-injured patients 5. Patients with recent hx of PUD

Question 36

Duration of antibiotics for VAP?

Answer 36

8 days

Question 37

Does prone positioning increase oxygenation?

Answer 37

Yes

Question 38

Tx for Swan-Ganz pulmonary artery injury?

Answer 38

1. Deflate balloon 2. Withdraw catheter 3. Ipsi side down 4. Increase PEEP 5. Angioembolization

Question 39

Physiologic effect of increasing dead space ventilation?

Answer 39

Hypoxemia and hypercapnia

Question 40

Differential diagnosis for cause of increased trach secretions?

Answer 40

Infection | Fluid overload

Question 41

Expected PaO2 with the following SaO2: 1. 97% 2. 90% 3. 75% 4. 50%

Answer 41

1. 100 mm Hg 2. 60 3. 40 4. 26

Question 42

Antidote for nitroglycerin toxicity?

Answer 42

Methylene blue

Question 43

Half life of amiodarone?

Answer 43

52 days

Question 44

Types of shock?

Answer 44

Inadequate tissue perfusion Hypovolemic Cardiogenic (pump failure) Extracardiac obstructive (tension PTX, cardiac tamponade) Distributive (septic, neurogenic, and traumatic)

Question 45

Goal UOP? Adult Pediatric Peds < 2 yo

Answer 45

Adult: 0.5-1 mg/kg/hr Pediatric: 1 ml/kg < 2 yo: 1-2 ml/kg

Question 46

Markers of resuscitation

Answer 46

Lactate | Base deficit

Question 47

What is base deficit?

Answer 47

Amount of fixed base (or acid) that must be added to an aliquot of blood to restore the pH to 7.4 Normal: 2 to -2 Mild: -3 to -9 Severe: >-10 Has been shown to be superior to pH in assessing the normalization of acidosis after shock resuscitation

Question 48

Hemorrhagic shock: Class I, II, III, IV - Blood loss mL - Blood loss % - HR - BP - Pulse pressure - RR - UOP - Mental status

Answer 48

Class I: <750 mL/<15%/<100/Nml/Nml/Nml/>30/Nml Class II: 750-1500 mL/15-30%/>100/Nml/Dec/20-30/20-30/mildly anxious Class III: 1500-2000 mL/30-40%/>120/Dec/Dec/30-40/5-15/Anxious & confused Class IV: >2000 mL/40%/>140/Dec/Dec/>35/Minimal/confused & lethargic

Question 49

MC cause of cardiogenic shock?

Answer 49

Anterior wall MI - also common is PE, myocardial or pulmonary contusion

Question 50

Beck's triad

Answer 50

Muffled heart sounds JVD (elevated CVP) Hypotension Pulsus paradoxus

Question 51

CO2 embolus treatment?

Answer 51

Pause the pneumoperitoneum Left lateral decubitus position Aspirate out the air from a central line in the right atrium

Question 52

How to differentiate ARDS from cardiogenic pulmonary edema?

Answer 52

Measure PAWP with Swan Ganz | <18 mm Hg = non-cardiogenic, confirms ARDS diagnosis