Infusion techniques for peripheral arterial thrombolysis

Area of Science:

• Vascular Surgery
• Interventional Radiology
• Pharmacology

Background:

• Acute limb ischaemia (ALI) is a critical condition caused by arterial blockage, potentially leading to irreversible damage and amputation if not treated promptly.
• Thrombolysis, using fibrinolytic drugs to dissolve blood clots, is a less invasive treatment option for ALI compared to surgery.
• This review is an update of a 2004 analysis, focusing on comparing different infusion techniques for fibrinolytic agents in ALI management.

Purpose of the Study:

• To compare the effectiveness of various infusion techniques used during peripheral arterial thrombolysis for treating patients with acute limb ischaemia.
• To evaluate outcomes such as limb salvage, amputation rates, mortality, vessel patency, and complications associated with different thrombolytic delivery methods.

Main Methods:

• Systematic search of multiple databases (Cochrane Vascular, CENTRAL, MEDLINE, Embase, CINAHL) and clinical trial registries up to October 2020.
• Inclusion of all randomized controlled trials (RCTs) comparing fibrinolytic infusion techniques for ALI.
• Assessment of risk of bias using the Cochrane 'Risk of bias' tool and certainty of evidence using GRADE. Due to heterogeneity, results were reported narratively, not via meta-analysis.

Main Results:

• Nine RCTs with 671 participants were included, assessing various techniques like intravenous (IV) vs. intra-arterial (IA) delivery, high-dose vs. low-dose, and continuous vs. forced infusion.
• Evidence certainty was very low to low due to study limitations, heterogeneity in populations, and outcome measures.
• Intra-arterial (IA) infusion showed higher likelihood of complete vessel patency (OR 13.22) compared to intravenous (IV) infusion, though with increased minor bleeding risk.
• High-dose and forced-infusion techniques reduced thrombolysis duration but were associated with more minor bleeding complications.

Conclusions:

• Insufficient evidence exists to support one thrombolytic regimen over another for improving amputation-free survival, amputation rates, or mortality in ALI.
• While IA infusion may enhance vessel patency, high-dose and IV regimens might increase risks of cerebrovascular accident (CVA) and major bleeding.
• Thrombolysis can be considered for marginally threatened limbs, but caution is advised for non-limb-threatening ischaemia due to potential risks.