question: Dear Doctor,  My son was operated for Arthroscopic ACL Reconstruction right knee using quadrupled hamstring using Biotransfix System. He has been experiencing palpitations, feeling of heart pounding fast, dizziness , short of breath associated with palpitations and a feeling of chest pressure.He is also having a low grade fever. His BP is 90/60 and his pulse rate is 113.  The doctor has suspected Pulmonary Embolism.  Kindly let me know what immediate action has to be taken and what are the risk factors he is facing.. I am eagerly waiting for your reply. Pl. oblige and cooperate.