Table 2.

—[Section 1.2] Structured Clinical Questions

Section	Population	Intervention and Comparator	Outcomes	Available Methodology
Patients receiving warfarin therapy
2.1	Patients receiving warfarin therapy who require an elective surgery or invasive procedure	In patients who require warfarin interruption before surgery to attain normal or near-normal INR at surgery, stopping warfarin 5-6 d before surgery vs stopping warfarin < 5 d before surgery	Hemostasis at time of surgery (INR)	Observational studies
2.2		In patients with warfarin interruption before surgery, resuming warfarin 12-24 h after surgery (evening of or next day) and when there is hemostasis vs resuming warfarin > 24 h from surgery	Hemostasis at time of surgery	Observational studies
2.3		INR testing to monitor anticoagulant effect of warfarin before and after surgery vs no testing	Hemostasis at time of surgery (aPTT, antifactor Xa)	Observational studies
2.4	Need for bridging anticoagulation during perioperative warfarin interruption	Bridging anticoagulation with heparin/LMWH vs no bridging	Stroke, other systemic embolism, major hemorrhage	Observational studies
	Patients considered at high risk for perioperative thromboembolism
	Patients considered at moderate risk for perioperative thromboembolism	Bridging anticoagulation with heparin/LMWH vs no bridging	Stroke, other systemic embolism, major hemorrhage	Observational studies
	Patients considered at low risk for perioperative thromboembolism	Bridging anticoagulation with heparin/LMWH vs no bridging	Stroke, other systemic embolism, major hemorrhage	Observational studies
2.5	Patients having minor dental, skin, or eye procedures	Continuing warfarin and coadministering an oral prohemostatic drug vs stopping warfarin 5-6 d before the procedure without administering a prohemostatic drug	ATE or VTE, major hemorrhage	RCTs, observational studies
	Patients receiving warfarin therapy and having a minor dental procedure
	Patients receiving warfarin therapy and having a minor skin procedure	Continuing warfarin around the time of the procedure vs stopping warfarin 5-6 d before the procedure	ATE or VTE, major hemorrhage	RCTs, observational studies
	Patients receiving warfarin therapy and having cataract procedure	Continuing warfarin around the time of the procedure vs stopping warfarin 5-6 d before the procedure	ATE or VTE, postoperative bleeding	RCTs, observational studies
Patients receiving antiplatelet therapy
3.4	Patients receiving antiplatelet therapy and having minor dental, skin, or eye procedure	Continuing antiplatelet drugs around the time of the procedure vs stopping antiplatelet drugs 7-10 d before procedure	Myocardial ischemia, postoperative bleeding	Observational
3.5	Patients receiving antiplatelet therapy and having elective noncardiac surgery	Continuing antiplatelet drugs around the time of the procedure vs stopping antiplatelet drugs 7-10 d before noncardiac surgery	Myocardial ischemia, postoperative bleeding	RCTs, observational studies
3.6	Patients receiving antiplatelet therapy and having elective CABG surgery	Continue antiplatelet drugs around the time of surgery vs stopping antiplatelet drugs 7-10 d before CABG	Myocardial ischemia, postoperative bleeding	Observational studies
3.7	Patients with a coronary stent receiving antiplatelet therapy and having elective surgery	In patients with a bare-metal coronary stent who require surgery within 6 wk of stent placement or patients with a drug-eluting coronary stent who require surgery within 6 mo of stent placement, continuing antiplatelet drugs around the time surgery vs stopping antiplatelet drugs 7-10 d before surgery	Myocardial ischemia, postoperative bleeding	Observational studies
Patients receiving heparin bridging anticoagulation
4.2	Patients who are receiving bridging anticoagulation with therapeutic-dose IV UFH	Stopping UFH 4-6 h before surgery vs stopping UFH closer to surgery	Postoperative bleeding	Observational studies
4.3	Patients who are receiving bridging anticoagulation with therapeutic-dose SC LMWH	Administering the last preoperative dose of LMWH ~24 h before surgery vs administering the last preoperative dose of LMWH ~12 h before surgery	Postoperative bleeding	Observational studies
4.4	Patients who are receiving bridging anticoagulation with therapeutic-dose SC LMWH	Resuming therapeutic-dose LMWH ≤ 24 h after surgery vs resuming LMWH > 24 h after surgery	Postoperative bleeding	Observational studies
	Having surgery associated with high bleeding risk
	Having surgery associated with low to moderate bleeding risk	Resuming therapeutic-dose LMWH ≤ 24 h after surgery vs resuming LMWH > 24 h after surgery	Postoperative bleeding	Observational studies

aPPT = activated partial thromboplastin time; ATE = aterial thromboembolism; CABG = coronary artery bypass graft; INR = international normalized ratio; LMWH = low-molecular-weight heparin; RCT = randomized controlled trial; SC = subcutaneous; UFH = unfractionated heparin.