Respiratory Distress Flashcards
What muscles are important for INSPIRATION?
- diaphragm ** (most impt)
- external intercostals
- accessory muscles: sternohyoid/scalene, sternomastoids, alae nasi
what is the function of the diaphragm during inspiration?
when the diaphragm contracts, the abdominal contents are moved caudally and ventrally. The chest cavity volume INCREASES and the pressure DECREASES. The ribs are lifted.
what is the function of the external intercostal muscles during inspiration?
when contracted, ribs are pulled cranially and ventrally.
T/F: The muscles of expiration are employed during normal tidal breathing
false – they are passive and not emplyed during normal tidal breathing
Expiration involves the diaphragm simply relaxing and the elastic properties of the lung and chest wall leading to recoil back to equilibrium.
when necessary (during distress/dyspnea), what muscles aid in expiration?
abdominal wall contraction leads to an increase in intra-abdominal pressure which pushes the diaphragm cranially and results in expiration. (volume of thoracic cavity decreases, so pressure increases)
_________ is outward signs of breathing difficulty
labored breathing
_________ is the sensation of breathlessness
dyspnea
__________ is positional increases in diffculty breathing
orthopnea
If a patient is having trouble on inspiration, where can you generally localize the problem to?
upper airway
If a patient is having trouble on expiration, where can you generally localize the problem to?
lower airway
If a patient is having increased effort during all phases of breathing, where can you generally localize the problem to?
parenchymal
If a patient is having short, shallow breaths, where can you generally localize the problem to?
pleural space
What are the THREE things to do when presented with a patient having respiratory difficulties?
- minimize stress
- oxygen supplementation
- sedation (bc dyspnea is stressful) with butorphanol IV (rapid onset, multiple routes of admin, minimal cardiac or resp effects, and reversible)
if all else fails, heavily sedate/induce and intubate (reduces stress and work of breathing and facilitates diagnostics)
What is a part of the “brief” physical exam for a patient in respiratory distress?
- visual inspection
- brief auscultation
- TPR
- mucous membrane assessment
give patient lots of breaks in between if necessary
Once a patient that presented for respiratory distress is calmer and stable, what diagnostics could you perform to get a better understanding of the underlying cause?
- full physical exam
- blood sample
- imaging – thoracic xrays, fluoroscopy, echocardiography, bronchoscopy, CT, ultrasound
what are upper airway diseases that can cause respiratory distress?
- laryngeal paralysis
- tracheal collapse
- foreign body
- polyps (cats)
- brachycephalic airway syndrome
what are 3 lower airway diseases that can cause respiratory distress?
- chronic bronchitis
- asthma
- eosinophilic bronchopneumonia
what are parenchymal diseases that can cause respiratory distress?
- pneumonia
- pulmonary edema
When assessing a patient who has all breathing phases affected (meaning parenchymal disease is most likely the cause), how can you differentiate between cardiac versus non-cardiac causes and provide therapy based on the difference?
history, signalment, and triage
if its CHF, the patient would be tachycardic and hypothermic
if its lung problem, the patient would have a normal HR and normal temp most likely.
once you’ve distinguished between the 2, you can give furosemide, bronchodilators, or steroids based on the most likely problem.
what is a characteristic radiographic feature for congestive heart failure?
pulmonary venous distention
(also left atrial enlargement)
what are radiographic findings that point you more towards a bronchial disease as opposed to heart disease causing respiratory difficulty?
bronchial pattern – donuts and rail road tracks.
what are pleural space diseases that can cause a patient to present with short, shallow breaths?
- pleural effusion
- pneumothorax
- diaphragmatic hernia
how can you definitively diagnose and treat a pleural effusion and/or pneumothorax?
thoracocentesis
How can you diagnose thoracic wall disease in patients with atypical signs of respiratory distress?
blood gas – high CO2
Thoracic wall disease can be things like neuro disease, muscular disease, or orthopedic disease that causes the patient to be unable to show typical signs of respiratory distress.
A high CO2 is supportive of a patient who is hypoventilating.
