General Principles

Anticoagulant and antiplatelet medications save lives in typical settings by preventing embolic stroke, pulmonary emboli, coronary thrombosis, and more.  But these therapies in the surgical setting risk major or catastropic bleeding.  The goal of managing these medications around the time of surgery is to minimize the risk of serious bleeding while minimizing the risk of being off these medications.  Management is guided by considering the risk of bleeding in surgery compared to the risk to the patient while on reduced or discontinued medication.  The general approach is to be off blood-thinning medications for a relatively short amount of time to permit safe surgery and then resume when wounds are hemostatic and bleeding risk has fallen.
 
For warfarin, this generally involves stopping 5-7 days before surgery.  During the time when the patient is off warfarin, the highest clot-risk patients are placed on a "bridging heparin" to maintain anticoagulation until just before surgery, while lower-risk patients receive no bridging.
 
For aspirin and clopidogrel (and other P2Y12 inhibitors), discontinuation depends on the indication of use.  When used for primary prevention (CAD, CVA, PVD), risk of thrombosis is so low that the agent is simply discontinued 5, 7, or 10 days before surgery.  However, when used in combination (DAPT) after PCI, the risk of thrombosis off medication(s) is higher and warrants careful consideration of risk and benefit of continuing both agents, delaying surgery, cutting back to one agent temporarily, or discontinuing both.
 
For DOAC's, the half-lives of these medications is short enough that bridging anticoagulation with heparin is generally not necessary.  The PAUSE trial protocol is currently the best (and possibly the only) evidence-based guidance on handling DOAC's perioperatively.
 
The best most current guidance on periprocedural management of anticoagulants and antiplatelet agents can be found in the external apps and websites offered in this app.  Go read about the details pertinent to your patient at hand.