Cardiothoracic surgery Flashcards
what graft vessel is usually used in a coronary artery bypass graft ?
saphenous vein
what are the 2 most serious complications of a coronary artery bypass graft?
Death
Stroke
what is the lifespan if bioprosthetic valves?
10 years
what is the downside of mechanical valves compared with bioprosthetic?
require lifelong anticoagulation with warfarin
what is the INR target range for mechanical valves
2.5 – 3.5
what are 3 major complications of mechanical heart valves?
Thrombus formation
Infective endocarditis
Haemolysis causing anaemia
what is a pericardial effusion?
where excess fluid collects within the pericardial sac
what is pericardial tamponade?
pericardial effusion is large enough to raise the intra-pericardial pressure. This increased pressure squeezes the heart and affects its ability to function
name 2 causes of a transudative effusion?
Congestive heart failure
Pulmonary hypertension
Name 3 exudative causes of pericardial effusion
Infection e.g. HIV, TB
Autoimmune e.g. Lupus, RA
Injury to pericardium e.g. post MI, trauma
Uraemia secondary to renal impairment
Cancer
Medications e.g. methotrexate
what are some symptoms of chronic pericarditis?
Chest pain
Shortness of breath
A feeling of fullness in the chest
Orthopnoea (shortness of breath on lying flat)
what are signs on examination of pericardial effusion?
Quiet heart sounds
Pulsus paradoxus (an abnormally large fall in blood pressure during inspiration, notably when palpating the pulse)
Hypotension
Raised JVP
Fever (with pericarditis)
Pericardial rub (with pericarditis)
what is the investigation of choice for pericardial effusion?
echocardiogram
what is the management of a pericardial effusion ?
Drainage -? needle pericardiocentesis, surgical drainage
Tx underlying cause
what are the 3 layers of the aorta?
intima, media and adventitia
what is a false aneurysm?
(or pseudoaneurysm) occur when the inner two layers (intima and media) rupture and there is dilation of the vessel, with the blood only being contained within the outer (adventitia) layer of the aorta.
what are some symptoms of thoracic aortic aneurysms?
Chest or back pain
Trachea or left bronchus compression may cause cough, shortness of breath and stridor
Phrenic nerve compression may cause hiccups
Oesophageal compression may cause dysphagia (difficulty swallowing food)
Recurrent laryngeal nerve compression may cause a hoarse voice
Name 3 subtypes of non-small cell lung cancer
Adenocarcinoma
Squamous cell carcinoma
Large-cell carcinoma
what type of lung cancer is responsible for paraneoplastic syndromes?
small cell lung cancer
what are the presenting features of lung cancer?
Shortness of breath
Cough
Haemoptysis
Finger clubbing
Recurrent pneumonia
Weight loss
Lymphadenopathy – often supraclavicular
what are some findings on chest xray that are suggestive of lung cancer?
Hilar enlargement
Peripheral opacity – a visible lesion in the lung field
Pleural effusion – usually unilateral in cancer
Collapse
State 3 causes of pneumothorax
Spontaneous
Trauma
Iatrogenic, for example, due to lung biopsy, mechanical ventilation or central line insertion
Lung pathologies such as infection, asthma or COPD
what is the 1st line investigation for a pneumothorax?
erect chest xray
what is used to detect a pneumothorax that is too small to see on CXR?
CT thorax
what is the management of a pneumothorax with no shortness of breath and less than a 2cm rim of air on the chest x-ray?
No treatment is required as it will spontaneously resolve
Follow up in 2 – 4 weeks is recommended
what is the management of a pneumothorax with shortness of breath and/or more than a 2cm rim of air on the chest x-ray?
Aspiration followed by reassessment
When aspiration fails twice, a chest drain is required
what are the landmarks of the triangle of safety?
The 5th intercostal space (or the inferior nipple line)
The midaxillary line (or the lateral edge of the latissimus dorsi)
The anterior axillary line (or the lateral edge of the pectoralis major)
state 2 key complications of chest drains
Air leaks around the drain site (indicated by persistent bubbling of fluid, particularly on coughing)
Surgical emphysema (also known as subcutaneous emphysema) is when air collects in the subcutaneous tissue
what are the signs of a tension pneumothorax?
Tracheal deviation away from side of the pneumothorax
Reduced air entry on the affected side
Increased resonance to percussion on the affected side
Tachycardia
Hypotension
what is the immediate management of a tension pneumothorax?
Insert a large bore cannula into the second intercostal space in the midclavicular line
what are the most common indications for a lung transplant?
Chronic obstructive pulmonary disease (COPD)
Pulmonary fibrosis
Cystic fibrosis
Pulmonary hypertension