Regional anesthesia for orthopedic procedures: What orthopedic surgeons need to know

Table 1 American Society of Regional Anesthesia guidelines for anticoagulant and antiplatelet drugs

Medication	Minimum time between last dose of medication and neuraxial injection or catheter placement	Minimum time after nerve/neuraxial cathether placement and administration of drug	Minimum time between last dose of drug and cathether removal	Minimum time between neuraxial injection or cathether removal and administration of drug
Anticoagulants for venous thromboembolism prophylaxis
Enoxaparin (Lovenox); prophylaxis, once daily	12 h	≥ 12 h	≥ 12 h	4 h
Enoxaparin (Lovenox); prophylaxis, b.i.d.	12 h	Contraindicated while catheter in place		4 h
Heparin SQ; prophylaxis; low-dose, b.i.d. and t.i.d.	4-6 h	Immediately	4-6 h	Immediately
Heparin SQ; prophylaxis; higher-dose, b.i.d. and t.i.d.	12 h and assessment of coagulation status	Safety of indwelling catheters has not been established for doses > 5000 Units SQ or total daily dose > 15000 Units SQ. Risk/benefit assessment required		Immediately
Dalteparin (Fragmin); prophylaxis, once daily	12 h	≥ 12 h	12 h	4 h
Anticoagulants at therapeutic doses
Heparin IV; full Dose	4-6 h and normal coagulation status	1 h, with close monitoring	4-6 h and normal coagulation status	1 h
Heparin SQ; therapeutic dose	24 h and assessment of coagulation status	Contraindicated while catheter in place		Immediately
Enoxaparin (Lovenox); therapeutic dose	24 h, consider checking anti-factor Xa level	Contraindicated while catheter in place		4 h
Apixaban (Eliquis)	72 h	Contraindicated while catheter in place		6 h
Rivaroxaban (Xarelto)	72 h	Contraindicated while catheter in place		6 h
Warfarin (Coumadin)	5 d and normal INR	Variable instructions regarding management of catheter		Immediately
Anti-platelet medications
NSAID’s	No restrictions, may increase risk of bleeding
Aspirin	No restrictions, may increase risk of bleeding
Plavix	5-7 d	24 h postoperatively; catheter may be maintained for 1-2 d due to delayed antiplatelet effect		Immediately if no loading dose given
Ticlodipine (Ticlid)	10 days	24 h postoperatively; catheter may be maintained for 1-2 d due to delayed antiplatelet effect		Immediately if no loading dose given
Ticagrelor (Brillinta)	5-7 d	Contraindicated while catheter in place		Immediately if no loading dose given

NSAID: Non-steroidal anti-inflammatory drug.