Lecture 23 11/8/24

Question 1

What is dyspnea?

Answer 1

subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity

Question 2

What are the signs of resp. distress?

Answer 2

-increased resp. rate
-increased resp. effort
-orthopnea/shortness of breath
-open mouth breathing
-cyanosis
-stridor

Question 3

What are the characteristics of resp. distress in the ER?

Answer 3

-common cause of presentation
-life threatening
-patient and owner both in distress

Question 4

What are the causes of resp. distress?

Answer 4

-hypoxemia resp. failure
-hypercapnic resp. failure

Question 5

What are the hallmarks of hypoxemia?

Answer 5

-PaO2 less than 80 mmHg
-SpO2 less than 95%

Question 6

What are the normal values for PaO2 and SpO2?

Answer 6

-PaO2 between 80 and 100 mmHg
-SpO2 greater than 95%

Question 7

What are the life threatening values for PaO2 and SpO2?

Answer 7

-PaO2 less than 60 mmHg
-SpO2 less than 90%

Question 8

What are the two forms of oxygen in the blood?

Answer 8

-dissolved in blood/PaO2
-carried by hemoglobin/SpO2 or SaO2

Question 9

What are the characteristics of pulse oximetry?

Answer 9

-differential absorption of infrared light by oxygenated and deoxygenated hemoglobin
-red and infrared wavelengths of light used
-oxygenated hemoglobin absorbs more infrared light

Question 10

What are the two types of pulse ox probes?

Answer 10

-transmissive probe
-reflectance probe

Question 11

What are the characteristics of a transmissive pulse ox probe?

Answer 11

-most commonly used
-can be placed on lip. tongue, pinna, toe webbing, prepuce, or vulva
-challenging in awake patients

Question 12

What are the characteristics of a reflectance pulse ox probe?

Answer 12

-often better tolerated
-must be used over a bony surface
-placed at the tail base, rib, metacarpal area, or metatarsal area

Question 13

What can affect pulse ox?

Answer 13

-ambient light
-peripheral vasoconstriction
-darkly pigmented skin
-hypothermia/hypoperfusion
-anemia
-tachycardia
-hyperbilirubinemia

Question 14

What are the limitations of pulse ox?

Answer 14

-poorly tolerated in awake patients
-must be over an area of pulsatile blood flow
-patient’s HR must match pulse ox reading
-abnormal Hb species
-carboxyhemoglobin
-methemoglobin

Question 15

What are the characteristics of arterial blood gas?

Answer 15

-gold standard
-technically challenging and painful
-need special equipment to run samples

Question 16

Which arterial sites are used to collect samples for arterial blood glass?

Answer 16

dogs:
-dorsal pedal
-femoral
-coccygeal
-sublingual
-dorsal auricular
cats:
-femoral

Question 17

What is measured on an arterial blood gas?

Answer 17

-PaO2
-SaO2
-PaCO2
-pH

Question 18

What are the characteristics of cyanosis?

Answer 18

-gray/blue discoloration of mucous membranes
-requires 5 mg/dL of deoxygenated hemoglobin to be visualized
-visualization can be affected by anemia, room lighting, and visual acuity

Question 19

What can cause respiratory failure?

Answer 19

-failure to ventilate
-failure to maintain airway
-failure to oxygenate

Question 20

What are the causes of hypoxemic resp. failure?

Answer 20

-pneumothorax
-hemothorax
-pleural effusion
-pneumonia
-pulmonary edema
-pulmonary contusions
-pulmonary thromboembolism

Question 21

What are the characteristics of hypercapnic resp. failure?

Answer 21

-can be due to failure of the resp. center, diaphragm, intercostal muscles, or by airway obstruction
-results in partial pressure of CO2 (PaCO2) greater than 60 mmHg

Question 22

What are the causes of hypercapnic failure?

Answer 22

-head trauma
-cervical spine disease
-lower motor neuron diseases
-laryngeal paralysis
-upper airway obstruction
-flail chest

Question 23

What are the characteristics of oxygen?

Answer 23

-most important therapeutic drug
-widely available
-relatively inexpensive
-FiO2 of 21% in room air
-FiO2 of 100% in medical oxygen

Question 24

What are the characteristics of medical oxygen?

Answer 24

-can cause oxygen toxicity
-may administer a lower conc. depending on route utilized
-should be humidify if used for more than a few hours

Question 25

What are the characteristics of flow-by oxygen?

Answer 25

-provides 25-40% oxygen -flow rate of 2 to 3 L a minute -well tolerated -can be used during initial patient treatment

Question 26

What are the characteristics of mask oxygen?

Answer 26

-requires tight fitting mask held to patient's face -can provide 50-60% oxygen with high oxygen flow rates -poorly tolerated

Question 27

What are the characteristics of nasal oxygen?

Answer 27

-unilateral or bilateral -easily placed -can provide 30-70% FiO2 -50 to 150 ml/kg/min

Question 28

Which tools can be used for oxygen administration?

Answer 28

-e-collar -intratracheal oxygen -nasal cannula -oxygen cage -intubation

Question 29

What are the characteristics of sedation?

Answer 29

-alleviates anxiety -excellent for cases with upper airway distress -may be used with caution with lower airway disease

Question 30

Which medications and admin routes are used for sedation?

Answer 30

butorphanol or acepromazine given IV, IM, or SQ

Question 31

How is stress minimalized in animals undergoing resp. distress?

Answer 31

-minimize handling -complete exam in stages -wait to perform major diagnostics until patient is stable -keep patient in quiet areas

Question 32

What is thoracocentesis used for?

Answer 32

-relieve pleural effusion -relieve pneumothorax -diagnostic tool/fluid collection

Question 33

What are the characteristics of intubation?

Answer 33

-ascertains patent airway -provides immediate control of oxygenation and ventilation -life saving -done when patient is in overt resp. distress

Question 34

What are the steps of tracheostomy?

Answer 34

-place patient in dorsal recumbency -make a midline incision -blunt dissection on midline -incision into trachea -stay sutures placed around dorsal and ventral aspects -insert tube

Question 35

Why do temporary tracheostomies require 24 hour nursing care?

Answer 35

-prone to obstruction with mucus -cleaning needed around stoma site -cuff needs deflated/reinflated every 4 hours

Question 36

What are the characteristics of cricothyrotomy?

Answer 36

-incision made into cricothyroid membrane --tracheostomy or ET tube is inserted directly into incision -faster than tracheostomy -less tissue dissection than tracheostomy

Question 37

What are the characteristics of TFAST?

Answer 37

-focused assessment with sonography for trauma -assess two sites on thorax -assess chest tube site and pericardial site

Question 38

Which sites are assessed with a Vet BLUE ultrasound?

Answer 38

-cranial -middle -perihilar -caudal

Question 39

What are the characteristics of thoracic radiographs?

Answer 39

-always indicated in any animal with trauma -can be used to assess for diaphragmatic hernia and pneumothorax

Question 40

What is the minimum data base?

Answer 40

-PCV -total solids -blood glucose -lactate

Question 41

Which advanced diagnostics are done in patients with resp. distress?

Answer 41

-CBC -chem -electrolytes -urinalysis

Question 42

Which diagnostics are done as indicated in resp. cases?

Answer 42

-bronchoscopy/tracheoscopy -thoracic CT -abdominal rads -abdominal ultrasound