Surgery versus thrombolysis for acute limb ischaemia: initial management.

BACKGROUND: Peripheral arterial thrombolysis has become established as a useful adjunct in the management of peripheral arterial ischaemia. Much has been learnt about indications, risks and benefits using this technique, although data from randomised controlled studies is not extensive. The optimal initial management of the acutely ischaemic leg needs to be determined.

OBJECTIVES: To determine if surgery or thrombolysis is the preferred option in the initial treatment of acute limb ischaemia.

SEARCH STRATEGY: The search strategy was that adopted by the Cochrane Review Group on Peripheral Vascular Diseases. Additionally, reference lists of papers resulting from this search were reviewed.

SELECTION CRITERIA: All randomised studies comparing thrombolysis and surgery in the management of acute limb ischaemia.

DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted independently by all three reviewers.

MAIN RESULTS: Patients with acute lesions of less than seven days duration had a significantly increased survival at one year for patients having thrombolysis, compared to those undergoing initial surgery [84% v 58%, p=0.01; Odds ratio (95% CI) 0.28 (0.13,0.63)] largely associated with a reduced level of in-hospital cardio-pulmonary complications (Ouriel 1994). Lesions less than 14 days duration fared better with initial lysis with a reduced amputation and reduced death rate at six months [15.3% v 37.5%; p=0.001; Odds ratio (95%CI) 0.29 (0.12,0.72)] (STILE 1994), compared to initial surgery. Analysis of the same trial at one year however revealed that native vessel thromboses had a more favourable outcome with initial surgery, largely due to continuing ischaemia in the lytic group [64% v 35%; p<0.0001; Odds ratio (95%CI) 3.26(1.96,5.52)] (Weaver 1996). Bypass graft thromboses less than 14 days old treated with initial thrombolysis were shown to have a reduced amputation rate (15% v 47%; p=0.05). However, overall, one year results revealed that thrombolysis of thrombosed grafts was associated with a higher level of continued ischaemia [73% v 50%; P=0.010; Odds ratio (95%CI) 2.72(1.27,5.80)] (Comerota 1996).

REVIEWER'S CONCLUSIONS: A universal initial treatment with either surgery or thrombolysis cannot be advocated on the available evidence. There is no overall difference in limb salvage or death at one year between initial surgery and initial thrombolysis. Thrombolysis may however be associated with a higher risk of ongoing limb ischaemia, and a higher overall risk of haemorrhagic complications including stroke. The higher risk of complications needs to be balanced against the risks of surgery in the individual patient.