Pulmonary embolus, while waiting for EMS

    A patient was sent home 10days ago s/p partial small bowel resection for crohns disease, she sudden start experiencing Shortness of breath, blood pressure 80/40, oxygen level 89% on room air, the physician suspect massive pulmonary embolus, while waiting for EMS to arrive the physician assistant place an EKG on the patient which reveals Right Ventricular Strain A. Explain why large pulmonary embolus interferes with oxygenation B. Explain why large pulmonary embolus causes right ventricular strain