Pulmonary Embolism in Cardiac Arrest

Pulmonary embolisms present with a broad variety of symptoms from chest pain to shortness of breath, and even fevers. Common exam findings include tachypnea and tachycardia. Risk factors include recent surgery, trauma, prolonged immobility, active cancer, birth control pills or hormone replacement therapy, or a history of prior embolism. 

Definitions

• Acute: Occuring with immediate symptoms
• Subacute: Presenting with days or weeks or occlusion
• Chronic: develops pulmonary hypertension overtime
• Massive: High risk embolism with hypotension, hemodynamically unstable, and potentially causing right heart failure and obstructive shock. 
• Submassive: Right ventricular dysfunction but stable. 
• Saddle: Embolism at the bifurcation of the main pulmonary artery. 
• Subsegmental: Occlusion of smaller vessels which is most likely to cause necrosis 

Pulmonary Embolism is the Arresting Patient

Patients who arrest with a strong suspicion of pulmonary embolism may be treated with TPA. Bedside ultrasound should be used to help rule out alternative causes, such as tamponade or aortic dissection. Bedside ultrasound should also be used to evaluate for right heart strain prior to TPA. 

The initial dose of TPA in a cardiac arrest varies depending on what study is being evaluated. Some doses include an initial bolus of 10-15mg of TPA followed by an influsion of 85-90mg over an hour. Local protocol calls for a single bolus of 50mg over 2 minutes in cardiac arrest. This should be followed by at least 15-20 additional minutes of CPR to allow for TPA to circulate. A second dose could be considered. 

Current data shows that there is no difference in outcome when comparing patients who do and do not receive TPA during cardiac arrest. The same data also does not show increased risk of severe bleeding when comparing these populations. Undifferentiated cardiac arrest is NOT an indication for TPA.