Oncologic Emergencies

Question 1

What is Cardiac Tamponade?

Answer 1

A life threatening emergency that occurs when excessive fluid or blood is in the pericardial sac. This leads to an increase pressure that compromises the heart’s ability to fill and pump. CO and overall systemic perfusion then decreases, leading to hemodynamic instability.

Question 2

How do you differentiate pericardial effusion and cardiac tamponade?

Answer 2

Pericardial effusion:
- Anatomic diagnosis
- Accumulation of fluid within the pericardial sac
- Usually develop overtime, which allows the heart time to adjust or compensate
- Has no hemodynamic consequence
Cardiac Tamponade:
- Physiologic diagnosis
- Excessive fluid accumulation in the pericardial sac
- Condition usually develops quite rapidly so the heart does not have time to adjust, and can lead to hemodynamic instability
- Severity depends on:
o How fast the fluid is accumulating
o How stretchable is the pericardium muscle

Question 3

Who is most at risk of cardiac tamponade?

Answer 3

Those with cancers that can infiltrate or metastasize to the heart (lung ca, breast ca, Hodgkins and Non-Hodgkins Lymphoma, Leukaemia) these pts are at high risk for develop Malignant Pericardial Effusions (MPE) and cardiac tamponade because the tumour can impede the lymphatic and venous pathway, which prevents the reabsorption of the serous fluid in the pericardial space. In addition, a tumour is very vascular and can easily bleed, which will expedite the development of cardiac tamponade.
- Radiation therapy > 4000 cGy, to the chest wall or chest area. Radiation rays can cause fibrosis to the heart membrane
- Medications that are cardiotoxic: anthracycline drugs, 5-FU, trastuzumab, anticoagulants. These can all increase someone’s risk of developing cardiac tamponade and MPE.
- Others: any trauma to the chest, myocardial infarction as it damages the heart muscle and makes it less plyable, pericarditis
- Kidney failure reduces the body’s ability to remove waste from the blood causing all kinds of electrolyte and protein imbalance that triggers fluid to accumulate in the pericardial space, hypothyroidism