Table 28.

—[Section 5.4] Summary of Findings: Fondaparinux vs IV UFH for Initial Anticoagulation of Acute PE^a-c,79

Outcomes	No. of Participants (Studies), Follow-up	Quality of the Evidence (GRADE)	Relative Effect (95% CI)	Anticipated Absolute Effects
				Risk With UFH	Risk Difference With Fondaparinux (95% CI)
Mortality	2,213 (1 study), 3 mo	Moderated,e due to imprecision	RR 1.20 (0.82-1.74)	43 per 1,000	9 more per 1,000 (from 8 fewer to 32 more)
Recurrent VTE	2,213 (1 study), 3 mo	Moderated,e due to imprecision	RR 0.75 (0.51-1.12)	50 per 1,000f	13 fewer per 1,000 (from 25 fewer to 6 more)
Major bleeding	2,213 (1 study), 3 mo	Moderated,e due to imprecision	RR 0.85 (0.49-1.49)	23 per 1,000g	4 fewer per 1,000 (from 12 fewer to 11 more)

The basis for the assumed risk (eg, the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). Working group grades of evidence are as follow: High quality, further research is very unlikely to change our confidence in the estimate of effect; moderate quality, further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate; low quality, further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate; very-low quality, we are very uncertain about the estimate. See Table 1 and 3 legends for expansion of abbreviations.

^aAll patients had acute, symptomatic, hemodynamically stable PE.

^bFondaparinux (5.0, 7.5, or 10.0 mg in patients weighing < 50, 50 to 100, or > 100 kg, respectively) SC once daily given for at least 5 days and until the use of VKAs resulted in an INR > 2.0.

^cUFH continuous IV infusion (ratio of the activated partial thromboplastin time to a control value of 1.5-2.5) given for at least 5 days and until the use of VKAs resulted in an INR > 2.0.

^dAllocation was concealed. Patients, providers, and data collectors were not blinded. Outcome adjudicators were blinded; 0.6% of randomized patients were lost to follow-up. Not stopped early for benefit.

^eCI includes values suggesting no effect and values suggesting either benefit or harm; relatively low number of events.

^fSixteen fatal VTE in fondaparinux group and 15 fatal VTE in UFH group.

^gFourteen patients in the fondaparinux group and 12 patients in the LMWH group had a major bleeding event during the initial period (6-7 d). Of these, one in the fondaparinux group and one in the UFH group were fatal.