Cyanosis in Dogs
Cyanosis is a medical condition characterized by blue colored skin and mucous membranes, which occurs as the result of inadequate amounts of oxygenated hemoglobin -- the molecule which carries oxygen to the body tissues -- or due to hemoglobin abnormalities.
Unfortunately, dogs that are suffering from cyanosis caused by advanced lung/airway disease and severe heart disease have a poor long-term prognosis.
Symptoms and Types
- Heart murmur
- Crackles heard when listening to the lungs
- Muffled heart sounds
- Harsh sounds upon inhalation
- Honking cough
- Difficulty breathing
- Cyanotic, cool, pale, painful, swollen limbs lacking a strong pulse
- Weakness
- Posterior (hind limb) paresis or paralysis
Causes
Originating in the Respiratory System
- Larynx (voice box): can be due to paralysis (acquired or congenital); collapse; spasm; swelling; trauma; cancer; chronic inflammatory disease
- Trachea: can be due to collapse; neoplasia; foreign body; trauma; underdevelopment
- Lower airway: can be due to pneumonia (viral, bacterial, fungal, allergic, mycobacteria, aspiration); chronic swelling of the bronchioles; allergies, asthma; chronic dilation of the bronchioles; cancer; foreign body; parasites; bruising of the lungs; swelling due to inhalation, snake bite, electric shock; near drowning
- Pleural space: may be due to air in the chest cavity; infectious (bacterial, fungal); pus in the chest cavity; blood in the chest cavity; cancer; trauma
- Chest wall, or diaphragm: may be related to congenital defects such as hernia around the heart or through the diaphragm (when an organ pushes through the wall, or enclosure that normally contains it); trauma (diaphragmatic hernia, fractured ribs); neuromuscular disease
Originating in the Cardiovascular System
- Congenital defects
- Acquired disease: may be linked to mitral valve (left side of heart valve between atrium and ventricle) disease; disease of heart muscle
- Fluid collection around the heart: due to cancer or unknown causes
- Clogging of lung blood vessels with a clot
- Pulmonary hypertension: unknown origin (idiopathic); right-to-left cardiac shunts (blood is diverted to another pathway)
- Peripheral blood vessel disease
Originating in the Neuromusculoskeletal System
- Brain-stem dysfunction: due to brain swelling; trauma; bleeding; cancer; drug-induced depression of the respiratory center
- Spinal cord dysfunction: may be due to swelling; trauma; vertebral fractures; disk slippage
- Neuromuscular dysfunction: may be caused by overdose of paralytic drugs; tick paralysis; botulism; coonhound paralysis
Methemoglobinemia
- Methemoglobin (metHb) binds to water molecules rather than oxygen molecules
- Elevated concentrations of methemoglobin in the red blood cells leads to tissue hypoxia due to reduced oxygen carrying capacity of blood
- Congenitally acquired NADH-methaemoglobin reductase (NADH-MR) deficiency: deficiency of an intracellular reductive enzyme, which helps keep methemoglobin at levels of less than two percent, preventing cyanosis
- May be linked to ingestion of oxidant chemicals: acetaminophen, nitrates, nitrites, phenacetin, sulfonamides, benzocaine, aniline dyes, dapsone
atrium
The superior chamber in an animal's heart.
ingest
To take food in by mouth
asthma
An allergic disorder that results in difficulty breathing.
enzyme
A substance that causes chemical change to another
hernia
The condition of having a part of a body part protruding through the tissue that would normally cover it
lavage
Irritating tissue with a great deal of some type of fluid
paresis
A type of paralysis that may be only slight; affects the way that an animal is able to move
pleura
The membrane that lines the inside of a lung
trocar
A type of needle-like tool that is used to puncture a cavity and draw out fluid or air
bronc
A horse who has not been broken; a wild horse.
lysis
The breakdown of something or the destruction of something, biologically speaking
vat
Term used to refer to a large tub or container used to hold liquids; may be used to dip animals into.
pus
A product made of fluid, cell waste, and cells
ion
An atom that has a positive or negative charge
ark
A term usually used in the context of care for rabbits; a little structure with a ridged roof that may be used to house rabbits.
otic
Anything having to do with the ear
nag
A type of horse that does not belong to a particular breed
ova
The word for female eggs
hypoxia
Less oxygen than normal in the blood
dilation
The widening of something
hypertension
High blood pressure
mitral valve
The fold of membrane found between the left atrium and left ventricle
radiograph
A record of body structures using an x-ray
idiopathic
Relating to a disease of unknown origin, which may or may not have arisen spontaneously
neuromuscular
The area found between the muscles and the endings of the nerves
pleural space
The area between the folds of the pleura; airtight
thoracocentesis
The puncturing of a hole in the wall of the chest as a means of drawing out fluid or air
mucous membrane
A special type of tissue that exudes mucus
intracellular
Inside the cell
urinalysis
An in-depth examination of the properties of urine; used to determine the presence or absence of illness
hemoglobin
The protein that moves oxygen in the blood
aspirate
a) inhaling b) getting out fluid or gas by the act of sucking.
thoracic
Pertaining to the chest
electrocardiograph
A tool that is used to create a record of the electrical activity in the myocardium
vertebra
A bone in the spinal column
diaphragm
The muscle in the abdomen that aids in breathing
ventricle
a) A cavity in certain animals b) Term refers to a rear chamber in the heart or a cavity in the brain
pulmonary
Pertaining to the lungs
prognosis
The prediction of a disease’s outcome in advance
trachea
The windpipe; it carries air from the bronchi to the mouth
