Respiratory emergencies (Conner) Flashcards
Muscles of inspiration
- Diaphragm most imp
- contraction:
- abdominal contents move caudally and ventrally
- chest cavity increases in volume in craniocaudal direction
- ribs lifted
- contraction:
- External intercostals
- contraction
- pulled cranially and ventrally
- contraction
- Scalene: accessory moscle of inspiration
- Sternomastoids: pull sternum cranially
- Alae nasi: nasal flare
During normal breathing abdomen
- DOES move
- abdominal muscles not involved in normal breathing
Muscles of expiration
- Not emplyed during normal tidal breathing
- Elastic properties of lung & chest wall
- recoil to equilibrium
- When needed
- adbominal wall contraction
- inc intraabdominal pressure
- pushes diaphragm cranially
Labored breathing
Def
- Outward signs of breathing difficulty
- often includes engagement of accessory muscles of inspiration and/or expiration
Dyspnea
def
- Sensation of breathlessness
- patient in trouble and panicking
Tachypnea
def
Increased respiratory rate
Orthopnea
Def
- Positional increases in difficulty
- vet patients often extend head, and neck, abduct elbows
Rapid localization of problem
- Upper respiratory
- problems on inspiration
- Lower airway
- problems on expiration
- Parenchymal
- increased effort during all phases
- Pleural space
- short, shallow breathing
*combinations are common
Minimize stress in cats
- don’t scruff
- hands off is better
- minimize stress
Approach to respiratory distress
Oxygen
- Doesn’t always help
- doesn’t hurt
- method of delivery may induce stress
- Oxygen cage
- Mask/flow by
- Hood
- Nasal cannula
Approach to respiratory distress
Sedation
- Dyspnea is stressful
- Ideal sedative
- rapid onset
- multiple routes admin
- minimal cardiac/resp effects
- reversible
- Butorphanol
- 0.1-0.3 mg/kg IV or IM
- repeat if needed
Three keys to approaching resp distress
TQ
- Minimize stress
- Oxygen
- Sedation
Contraindications for oxygen
- If your patient is on fire
If all else fails
- Sedate and intubate
- reduces stress and work of breathing
- Short-term solution to facilitate diagnostics
- May need to continue with mechanical ventilation
*Better to intubate a living patient than a dead patient that just suffered resp distress
Diagnostics
Initially
- Brief physical exam
- visual inspect
- brief auscultation
- (T)PR
- mm
- Take step-by-step approach
- Give patient lots of breaks
Diagnostics
When patient more calm and stable
- Full physical exam
- Blood sample
- Imaging
- thoracic rads
- Fluoroscopy
- echocardiography
- bronchoscopy
- comuted tomography
Rule #1 of diagnostics in respiratory cases
Don’t kill your patient to get diagnostics
-that’s a necropsy!
Common upper airway dz
- Lar par
- Tracheal collapse
- foreign bodies
- polyps
- brachycephalic airway syndrome
Lower airway disease
- Feline bronchial disease (asthma)
- Chronic bronchitis
Parenchymal disease
Primary Cardiac Disease
- Very young and very old
- small breed dogs
- Maine coon cats
- Presence of murmur or arrhythmia
- history of cough (dog)
*TX WITH LASIX (FUROSEMIDE)
Parenchymal Disease
Non-cardiac dz
- any age or breed
- history of vomiting or recent anesthesia
- coughing
- cats or dogs
- severe concurrent dz
*TX with Bronchodilators: these can exacerbate heart failure
Cats with heart dz don’t
cough
Radiographs
Get good at differentiating heart failure from parenchymal dz
Big left atrium
On rads what will tel you it’s heart dz instead of pulmonary dz?
- Pulmonary arteries and veins
- A, B, V: artery, bronchus vein
- Is artery distended compared to vein
3 Radiographic lung patterns
- Alveolar dz: gunk in alveoli
- looks like tree in the snowstorm in winter
- primary parenchyal problem
- Airway dz: thickening of airways
- looks linke tramlines and donuts
- Interstial pattern
- white noise one
- Alveolar pattern
Pleural space disease
- Pleural effusion
- Pneumothorax
- Diaphragmatic hernia
Radiographs of pleural space disease
- lose ability to see vasculature
- lose ability to see airways
- rounded lungs
Pleural space disease
Thoracic wall disease
- Neurologic disease
- Muscular disease
- Orthopedic disease
*Harder to recognize, don’t look dyspnic, can’t become orthopnic
Tetraparetic dog with inc abdominal effort and open mouth breathing
- Hypoventilating
- get a blood gas to confirm high CO2 (normal 40, 50 high)
- Then intubate and breath for him
- because of his high CO2 and respiratory paralysis
Labored breathing cat, short in all phases (restricted breathing)
Short and shallow breathing, lung sounds quiet bilaterally
- Tap the chest (can do diagnostic tap)
- pneumo-go higher in chest
- fluid-go more ventral on chest
5 month old male lab mix hit by car
Severe resp distress probs severe pulmonary contusions (diffuse, alveolar pattern)
- Knock him out and intubate him
- Maybe dump him…if lots of fluid/blood in airways
- this may not work when alive b/c of resistance
