I also expect that you won't be out long on anticoagulants. I'd think a bigger issue is your foot's ability to handle swimming and walking with all the gear.
Post-op anticoagulant therapy is not unusual in orthopedic procedures although much of the literature focuses on major surgeries involving the pelvis and lower limbs rather than the ankle or foot. Furthermore, without pre-operative DVT therapy, incidence rates range about 40-60% or higher for the former procedures and 4% or less for the latter. Among the contributors to increased thrombotic risk are surgical materials and drugs, transfusions, complications and technique, and post-op immobility.
Generally in post-surgery situations, low-molecular weight heparin (LMWH) anticoagulants (e.g. enoxaparin) are preferred because these have lower bleeding risk than "regular" anticoagulants and, although an injection is involved, can be administered on an out-patient basis. For major orthopedic procedures, the usual course of LMWH anticoagulants is a week to 12 days. Followup, usually oral non-LMWH, anticoagulants could be prescribed for possibly weeks or months, especially when there's persistent immobility or other risk factors for DVT. Oral LMWH preparations have had a spotty record (e.g. ximelagatran) but quite recently, newer formulas have been grinding toward FDA approval (e.g. rivaroxaban).
Along with platelets, immediate measures for clotting status are PT (prothrombin) and PTT (partial thromboplastin time) rates. (There's a ton of other blood components, proteins, and minerals which support clotting but these two are basic indicators.) INR (International Normalised Ratio) is a calculated measure of clotting time, based on a patient's baseline PT. Generally, desired normal values are in the range of 10-13sec for PT, 25-40sec for PTT, and while under anticoagulant therapy, 2-3 for INR (i.e. double or triple PT times above baseline).
