A single blind randomised controlled trial of the impact on patient-reported pain of arm elevation versus exsanguination prior to tourniquet inflation

Abstract

Aims: The aim of this study was to compare the pain caused by the application of a tourniquet after exsanguination of the upper limb with that occurring after simple elevation.

Patients and methods: We used 26 healthy volunteers (52 arms), each of whom acted as their own matched control. The primary outcome measure was the total pain experienced by each volunteer while the tourniquet was inflated for 20 minutes. This was calculated as the area under the pain curve for each individual subject. Secondary outcomes were pain at each time point; the total pain experienced during the recovery phase; the ability to tolerate the tourniquet and the time for full recovery after deflation of the tourniquet.

Results: There was a significant difference in the area under the pain curves in favour of exsanguination (mean difference 8.4; 95% confidence interval (CI) 3.0 to 13.7, p = 0.004). There was no difference between the dominant and non-dominant arms (mean difference -0.2; 95% CI -23.2 to 22.8, p = 0.99). The area under both recovery curves were similar (mean difference 0.7; 95% CI -6.0 to 4.6, p = 0.78). There was no statistical difference in recovery time, the actual mean difference being 30 seconds longer in the elevation group (p = 0.06).

Conclusion: Many orthopaedic and plastic surgery procedures are done under local anaesthetic or regional block where a bloodless field and a motionless patient are essential. Optimising patient comfort during surgery with the tourniquet inflated is thus a priority. This study is useful in that it compares two common methods of preparation of the upper limb prior to tourniquet inflation and which have not previously been compared in this context. Following on the results of this study, we can confidently conclude that exsanguinating the upper limb before inflating a tourniquet is more comfortable than simply elevating the arm for patients undergoing a procedure under local or regional block, both during the procedure and in the recovery phase.

Take home message: Exsanguination rather than elevation is recommended in order to minimise patient discomfort and optimise the surgical field.

Keywords: elevation; exsanguination; pain; pain score; tolerance; tourniquet; upper limb surgery.