Effects of transcutaneous electrical nerve stimulation on pain, walking function, respiratory muscle strength and vital capacity in kidney donors: a protocol of a randomized controlled trial.

BMC Nephrology 2013; 14: 7.

Aims
To assess the effects of transcutaneous electrical nerve stimulation (TENS) on pain, walking function, respirator muscle strength and vital capacity in kidney donors.

Interventions
Participants will be administered with active TENS + analgesics for one hour or placebo TENS + analgesics.

Participants
74 living kidney donors to undergo nephrectomy performed by two approaches: lumbotomy and the subcostal route.

Outcomes
The primary outcome includes pain intensity and the secondary outcomes are respiratory muscle strength, vital capacity and walk function.

Follow-up
Immediately after the one hour TENS.

CET Conclusions
This protocol describes a study of the use of transcutaneous electrical nerve stimulation (TENS) in kidney donors. TENS has been shown to reduce pain and respiratory complication rates in other types of surgery, and the authors hypothesise that it may also help in the post-operative period following donor nephrectomy. A study of this nature is not easy to design. The authors have attempted to blind and placebo-control using a dummy TENS machine that delivers current that rapidly decreases to zero after the device is switched on. Clearly if the donors have knowledge that TENS delivers a continuous sensation during treatment, then they will be able to ascertain their study group (although this is perhaps unavoidable). One aspect that is not well controlled is the concomitant use of analgesia – patients will be allowed “prescription pain medication” although this is not described in further detail. The use of analgesia may vary between groups and as such should be included as a secondary outcome. It should also be noted that the proposed duration of treatment is only one hour – this may not be long enough to demonstrate a clinically significant difference in pain over the longer postoperative course. Previous studies have utilised TENS for 24-48 hours postoperatively, and perhaps a series of treatments over the first one or two post-operative days would be more appropriate.

Quality notes
Protocol - quality assessment is not appropriate.

Trial registration
Registro Brasileiro de Ensaios Clinicos (ReBEC) – RBR-8xtkjp

Funding source
Non-industry funded