Surgery versus thrombolysis for initial management of acute limb ischaemia.

Background: Both peripheral arterial thrombolysis and surgery can be used in the management of peripheral arterial ischaemia. Much is known about the indications, risks, and benefits of thrombolysis. However, whether thrombolysis works better than surgery for initial management of acute limb ischaemia remains unknown. This is the second update of the review first published in 2002.

Objectives: To determine whether thrombolysis or surgery is the more effective technique in the initial management of acute limb ischaemia due to thromboembolism.

Search Methods: For this update, the Cochrane Vascular Information Specialist (CIS) searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE Ovid, Embase Ovid, CINAHL, AMED, and clinical trials registries up to 7 May 2018.

Selection Criteria: All randomised controlled studies comparing thrombolysis and surgery for initial treatment of acute limb ischaemia.

Data Collection And Analysis: We independently assessed trial quality and extracted data. Agreement was reached by consensus. We performed analyses using odds ratios (ORs) and 95% confidence intervals (CIs).

Main Results: We identified no new studies for this update. We included five trials with a total of 1292 participants; agents used for thrombolysis were recombinant tissue plasminogen activator and urokinase. Trials were generally of moderate methodological quality. The quality of evidence according to GRADE was generally low owing to risk of bias (lack of blinding), imprecision in estimates, and heterogeneity.Trial results showed no clear differences in limb salvage, amputation, or death at 30 days (odds ratio (OR) 1.02, 95% confidence interval (CI) 0.41 to 2.55, 4 studies, 636 participants; OR 0.97, 95% CI 0.51 to 1.85, 3 studies, 616 participants; OR 0.59, 95% CI 0.31 to 1.14, 4 studies, 636 participants, respectively), and we rated the evidence as low, low, and moderate quality, respectively. Trial results show no clear differences for any of the three outcomes at six months or one year between initial surgery and initial thrombolysis. A single study evaluated vessel patency, so no overall association could be determined (OR 0.46, 95% CI 0.08 to 2.76, 20 participants; very low-quality evidence). Evidence of increased risk of major haemorrhage (OR 3.22, 95% CI 1.79 to 5.78, 4 studies, 1070 participants; low-quality evidence) and distal embolisation (OR 31.68, 95% CI 6.23 to 161.07, 3 studies, 678 participants; very low-quality evidence) was associated with thrombolysis treatment at 30 days, and there was no clear difference in stroke (OR 5.33, 95% CI 0.95 to 30.11, 5 studies, 1180 participants; low-quality evidence). Participants treated by initial thrombolysis had a greater reduction in the level of intervention required, compared with a pre-intervention prediction, at 30 days (OR 9.06, 95% CI 4.95 to 16.56, 2 studies, 502 participants). None of the included studies evaluated time to thrombolysis as an outcome.

Authors' Conclusions: There is currently no evidence in favour of either initial thrombolysis or initial surgery as the preferred option in terms of limb salvage, amputation, or death at 30 days, six months, or one year. Low-quality evidence suggests that thrombolysis may be associated with higher risk of haemorrhagic complications and ongoing limb ischaemia (distal embolisation). The higher risk of complications must be balanced against risks of surgery in each individual case. Trial results show no statistical difference in stroke, but the confidence interval is very wide, making it difficult to interpret whether this finding is clinically important. We used GRADE criteria to assess the quality of the evidence as generally low. We downgraded quality owing to risk of bias, imprecision, and heterogeneity between included studies.