Chapter 62: Respiratory Distress

Question 1

Suggests HF is the cause of Dyspnea

Answer 1

S3 gallop or pulmonary venous congestion/ interstitial edema (especially with concomitant cardiomegaly) on chest
radiograph

Question 2

Most immediate Life-Threatening Causes of Dyspnea

Answer 2

Upper airway obstruction: angioedema, hemorrhage
Tension pneumothorax
Pulmonary embolism
Neuromuscular weakness: myasthenia
gravis, Guillain-Barré syndrome,
botulism
Fat embolism

Question 3

Hallmark of significant right-to-left shunting

Answer 3

failure of arterial oxygen levels to increase in response to supplemental oxygen

Question 4

Acute compensatory mechanisms for hypoxemia

Answer 4

1. Inc minute ventilation
2. Pulmonary arterial vasoconstriction decreases perfusion to hypoxic alveoli
3. Sympathetic tone increases and improves oxygen delivery by increasing cardiac output –> Inc HR

Question 5

Chronic compensatory mechanisms for hypoxemia

Answer 5

1. Inc RBC cell mass and decreased tissue oxygen demands
2. displays polycythemia and change in body habitus (Pulmonary cachexia)

Question 6

acute compensatory mechanisms are always activated when Pao2 reaches what value

Answer 6

60 mm Hg (8 kPa)

Question 7

Compensatory mechanisms for hypoxemia fail when PaO2 falls below what value?

Answer 7

20 mm Hg (2.67 kPa) = Central depression of respiration

Question 8

True or False: Cyanosis, the blood or tissue discoloration associated with a lowered arterial oxygenation saturation, is a sensitive or specific indicator of hypoxemia

Answer 8

FALSE

Question 9

Level of PaCO2 that can cause cardiovascular collapse

Answer 9

Acute elevations of PaCO2 >100 mmm Hg

Question 10

Hallmark of acute bronchitis

Answer 10

Productive cough

Question 11

Acute causes of cough

Answer 11

Upper respiratory infection: rhinitis, sinusitis, pertussis
Lower respiratory tract infection: bronchitis, pneumonia
Allergic reaction
Asthma
Environmental irritants
Transient airway hyperresponsiveness
Foreign body

Question 12

Reduces coughing in patients with acute bronchitis

Answer 12

Naproxen

Question 13

Tx for intractable coughing paroxysms in the ED

Answer 13

4 mL of 1% or 2% preservative-free lidocaine (40 or 80 milligrams) by nebulization.

Question 14

Only drug that is US FDA approved for intractable hiccups

Answer 14

Chlorpromazine 25-50 mg IV; repeat in 2-4 hrs if needed

Maintenance dose: 25-50mg PO 3-4 times a day

Question 15

TRUE or FALSE: The detection of cyanosis is subjective and is not a sensitive indicator of the state of arterial oxygenation

Answer 15

TRUE

cyanosis is determined by the absolute amount of deoxygenated hemoglobin in the blood

Question 16

pleural fluid required to be detectable in CXR

Answer 16

150-200ml

Question 17

limit therapeutics Thoracentesis to what amount?

Answer 17

1000ml - 1500 L
(drainage of larger volumes are associated with reexpansion pulmonary edema)

Question 18

A significant pleural effusion is
large enough to produce a pleural fluid strip ___ wide on lateral
decubitus radiographic views or by US.

Answer 18

> 10 mm

Question 19

examples of Transudative causes of Pleural effusion

Answer 19

common: Heart Failure
Less common: Cirrhosis with ascites, Peritoneal Dialysis, Nephrotic Syndrome

Question 20

Detection of exudative pleural effusion
* Light criteria for pleural exudate: 1 or more of the following present:
* Pleural fluid/serum protein ratio of ___
or
* Pleural fluid/serum LDH ratio __
or
* Pleural fluid LDH greater than ____ of the upper limit for serum LDH

Answer 20

Detection of exudative pleural effusion
* Light criteria for pleural exudate: 1 or more of the following present:
* Pleural fluid/serum protein ratio >0.5
or
* Pleural fluid/serum LDH ratio >0.6
or
* Pleural fluid LDH greater than two thirds of the upper limit for serum LDH

Question 21

A pleural fluid pH of ___ predicts development of empyema or persistence and indicates need for thoracostomy tube drainage.

Answer 21

pH <7.10 predicts development of emphyema or indicates need for thoracostomy drainage