Tourniquet in knee surgery.
The tourniquet is a surgical device composed of a round pneumatic cuff in which air at high pressure can be inflated with an automatic programmable pump to avoid bleeding and technical impediment. Comprehensive searches of Medline, Cochrane and Google Scholar databases were performed for studies regarding tourniquet application in arthroscopic and open surgery of the knee. The methodological quality of each study was evaluated using the Coleman methodology score (CMS). The use of a tourniquet does not lead to significant increase in the risk of major complications, and there is no difference in clinical outcome in the medium term. The inflated cuff does prevent intraoperative blood loss, but hidden blood loss is not avoided completely. There is a statistically significantly higher occurrence of deep vein thrombosis in patients who undergo surgery with tourniquet, but the clinical relevance of this finding is uncertain. The heterogeneity in terms of inflating pressure and duration of application of tourniquet in the single studies makes it very difficult to compare the outcomes of different investigations to draw definitive conclusions. Standardization of pressure and application time of the cuff could allow a comparison of the data reported by the trials. Better study methodology should be also implemented since the mean CMS considering all the reviewed articles was 57.6 of 100. More and better designed studies are needed to produce clear guidelines to standardize the use of tourniquet in knee procedures.