Changes

==Introduction==

==Introduction==

Pulmonary thromboembolism describes the '''occlusion of pulmonary vessels by a clot'''. It has usually arisen from the systemic venous circulation, embolises to the pulmonary circulation and causes obstruction of the arterial supply to an area of the lung. This results in '''ventilation perfusion mismatch''' occuring where there are areas of the lung which continue to be ventilated but do not receive adequate blood supply. This can result in '''severe hypoxia''' and marked signs of respiratory distress if the area of underperfused but ventilated lung is large.

Pulmonary thromboembolism describes the '''occlusion of pulmonary vessels by a clot'''. It has usually arisen from the systemic venous circulation, embolises to the pulmonary circulation and causes obstruction of the arterial supply to an area of the lung. This results in '''ventilation perfusion mismatch''' occurring where there are areas of the lung which continue to be ventilated but do not receive adequate blood supply. This can result in '''severe hypoxia''' and marked signs of respiratory distress if the area of underperfused but ventilated lung is large.

It can lead to pulmonary hypertension and result in pleural effusion.

It can lead to [[Pulmonary Hypertension|pulmonary hypertension]] and result in pleural [[:Category:Effusions|effusion]].

'''Causes''' of pulmonary thromboembolism include:

'''Causes''' of pulmonary thromboembolism include:

:'''Cardiac disease''': ''[[Dirofilaria immitis]]'', [[Dilated Cardiomyopathy|dilated cardiomyopathy]], [[Mitral Valve Dysplasia|chronic mitral valve insufficiency]], [[Endocarditis|endocarditis]]

:'''Cardiac disease''': ''[[Dirofilaria immitis]]'', [[Dilated Cardiomyopathy|dilated cardiomyopathy]], [[Mitral Valve Dysplasia|chronic mitral valve insufficiency]], [[Endocarditis|endocarditis]]

:'''Neoplasia''': lymphosarcoma, bronchoalveolar carcinoma, pancreatic carcinoma

:'''Neoplasia''': [[lymphosarcoma]], bronchoalveolar carcinoma, pancreatic carcinoma

:'''[[Disseminated Intravascular Coagulation]]'''

:'''[[Disseminated Intravascular Coagulation]]'''

:'''Sepsis'''

:'''Sepsis'''

==Clinical Signs==

==Clinical Signs==

Usually '''non-specific'''.  

Clinical signs are usually '''non-specific'''. There may be an acute onset of '''respiratory distress''', with increased depth, rate and effort of breathing. Patients may also present with an acute onset of signs of [[Heart Failure, Right-Sided|'''right sided heart failure''']] due to the sudden increase in pulmonary vascular resistance.

There may be signs of an '''underlying disease''' such as [[Hyperadrenocorticism|Cushing's]] or intestinal disease.

 

 

There may be signs of an '''underlying disease''' such as Cushing's or intestinal disease.

==Diagnosis==

==Diagnosis==

Diagnosis is '''difficult ante-mortem'''.

Diagnosis is '''difficult ante-mortem'''.  

'''History and clinical signs''' are usually vague and non-specific.

'''History and clinical signs''' are usually vague and non-specific.

This primarily involves '''treating the underlying cause'''.

This primarily involves '''treating the underlying cause'''.

'''Supportive care''' includes oxygen supplementation, strict cage confinement and careful parenteral fluid therapy..

'''Supportive care''' includes oxygen supplementation, strict cage confinement and careful parenteral [[:Category:Fluid Therapy|fluid therapy]].

'''Anticoagulant therapy''' should be considered in severe cases to prevent extension of the clot within the pulmonary circulation.

'''Anticoagulant therapy''' should be considered in severe cases to prevent extension of the clot within the pulmonary circulation. '''Heparin''' has a rapid onset and short-term effects.

'''Heparin''' has a rapid onset and short-term effects.

'''Fibrinolytic therapy''' is very expensive and lacks selectivity, but includes drugs such as streptokinase, urokinase and tissue plasminogen activator.

'''Prognosis''' is poor to guarded in cats and dogs. Recurrence is possible, especially if the cause has not been resolved.

'''Prognosis''' is poor to guarded in cats and dogs. Recurrence is possible, especially if the cause has not been resolved.

Boswood, A. (2010) '''Pulmonary parenchymal disease''' ''RVC Student Notes''

Boswood, A. (2010) '''Pulmonary parenchymal disease''' ''RVC Student Notes''

[[Category:To Do - Helen]]

 

[[Category:To Do - Review]]

[[Category:Respiratory Diseases - Dog]]

[[Category:Vascular Diseases - Dog]]

[[Category:||Expert Review - Small Animal]]

[[Category:Cardiovascular System - Vascular Pathology]]