Which dressing do donor site wounds need?: study protocol for a randomized controlled trial

Donor site wounds after split-skin grafting are rather 'standard' wounds. At present, lots of dressings and topical agents for donor site wounds are commercially available. This causes large variation in the local care of these wounds, while the optimum 'standard' dressing for local wound care is unclear. This protocol describes a trial in which we investigate the effectiveness of various treatment options for these donor site wounds. A 14-center, six-armed randomized clinical trial is being carried out in the Netherlands. An a-priori power analysis and an anticipated dropout rate of 15% indicates that 50 patients per group are necessary, totaling 300 patients, to be able to detect a 25% quicker mean time to complete wound healing. Randomization has been computerized to ensure allocation concealment. Adult patients who need a split-skin grafting operation for any reason, leaving a donor site wound of at least 10 cm2 are included and receive one of the following dressings: hydrocolloid, alginate, film, hydrofiber, silicone dressing, or paraffin gauze. No combinations of products from other intervention groups in this trial are allowed. Optimum application and changes of these dressings are pursued according to the protocol as supplied by the dressing manufacturers. Primary outcomes are days to complete wound healing and pain (using a Visual Analogue Scale). Secondary outcomes are adverse effects, scarring, patient satisfaction, and costs. Outcome assessors unaware of the treatment allocation will assess whether or not an outcome has occurred. Results will be analyzed according to the intention to treat principle. The first patient was randomized October 1, 2009. This study will provide comprehensive data on the effectiveness of different treatment options for donor site wounds. The dressing(s) that will prevail in effectiveness, satisfaction and costs will be promoted among clinicians dealing with such patients. Thus, we aim to contribute a well-designed trial, relevant to all clinicians involved in the care for donor site wounds, which will help enhance uniformity and quality of care for these patients. http://www.trialregister.nl, NTR1849. Date registered: June 9, 200

Differential predictors of acute post-surgical pain intensity after abdominal hysterectomy and major joint arthroplasty

Author's personal copyBACKGROUND Psychological factors have a significant role in post-surgical pain, and their study can inform pain management. PURPOSE The aims of this study are to identify psychological predictors of post-surgical pain following abdominal hysterectomy (AH) and major joint arthroplasty (MJA) and to investigate differential predictors by type of surgery. METHOD One hundred forty-two women undergoing AH and 110 patients undergoing MJA were assessed 24 h before (T1) and 48 h after (T2) surgery. RESULTS A predictive post-surgical pain model was found for AH and MJA yielding pre-surgical pain experience and pain catastrophizing as significant predictors and a significant interaction of pre-surgical optimism and surgery type. Separate regression models by surgery type showed that pre-surgical optimism was the best predictor of post-surgical pain after MJA, but not after AH. CONCLUSIONS Findings highlight the relevance of psychological predictors for both surgeries and the value of targeting specific psychological factors by surgery type in order to effectively manage acute post-surgical pain.Supported by a project grant (PTDC/SAU-NEU/108557/2008) and by a PhD grant (SFRH/BD/36368/2007) from the Portuguese Foundation of Science and Technology, COMPETE, and FEDE

Skin impedance is not a factor in transcutaneous electrical nerve stimulation effectiveness

Carol GT Vance,1 Barbara A Rakel,1,2 Dana L Dailey,1 Kathleen A Sluka1,2 1Department of Physical Therapy and Rehabilitation Science, University of Iowa Carver College of Medicine, 2University of Iowa, College Nursing Iowa City, IA, USA Objective: Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological intervention used to manage pain using skin surface electrodes. Optimal electrode placement is unclear. We hypothesized that better analgesia would occur if electrodes were placed over sites with lower skin impedance. Optimal site selection (OSS) and sham site selection (SSS) electrode sites on the forearm were identified using a standard clinical technique. Methods: Experiment 1 measured skin impedance in the forearm at OSS and SSS. Experiment 2 was a crossover design double-blind randomized controlled trial comparing OSS-TENS, SSS-TENS, and placebo TENS (P-TENS) to confirm differences in skin impedance between OSS and SSS, and measure change in pressure pain threshold (PPT) following a 30-minute TENS treatment. Healthy volunteers were recruited (ten for Experiment 1 [five male, five female] and 24 for Experiment 2 [12 male, 12 female]). TENS was applied for 30 minutes at 100 Hz frequency, 100 µs pulse duration, and “strong but nonpainful” amplitude. Results: Experiment 1 results demonstrate significantly higher impedance at SSS (17.69±1.24 Ω) compared to OSS (13.53±0.57 Ω) (P=0.007). For Experiment 2, electrode site impedance was significantly higher over SSS, with both the impedance meter (P=0.001) and the TENS unit (P=0.012) compared to OSS. PPT change was significantly greater for both OSS-TENS (P=0.024) and SSS-TENS (P=0.025) when compared to P-TENS. PPT did not differ between the two active TENS treatments (P=0.81). Conclusion: Skin impedance is lower at sites characterized as optimal using the described technique of electrode site selection. When TENS is applied at adequate intensities, skin impedance is not a factor in attainment of hypoalgesia of the forearm in healthy subjects. Further investigation should include testing in patients presenting with painful conditions. Keywords: transcutaneous electrical nerve stimulation, pain, impedance, electrode site selectio

Development of a method to maximize the transcutaneous electrical nerve stimulation intensity in women with fibromyalgia

Carol GT Vance,1 Ruth L Chimenti,1 Dana L Dailey,1 Katherine Hadlandsmyth,2 M Bridget Zimmerman,3 Katharine M Geasland,1 Jonathan M Williams,4 Ericka N Merriwether,1,5 Li Alemo Munters,4 Barbara A Rakel,6 Leslie J Crofford,4 Kathleen A Sluka1 1Department of Physical Therapy and Rehabilitation Science, The University of Iowa Carver College of Medicine, Iowa City, IA, USA; 2Department of Anesthesia, College of Medicine, University of Iowa, Iowa City, IA, USA; 3Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA, USA; 4Department of Medicine/Rheumatology & Immunology, Vanderbilt University, Nashville, TN, USA; 5Department of Physical Therapy, New York University, New York, NY, USA; 6College of Nursing, University of Iowa, Iowa City, IA, USA Introduction: Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacological intervention clinically used for pain relief. The importance of utilizing the adequate stimulation intensity is well documented; however, clinical methods to achieve the highest possible intensity are not established. Objectives: Our primary aim was to determine if exposure to the full range of clinical levels of stimulation, from sensory threshold to noxious, would result in higher final stimulation intensities. A secondary aim explored the association of pain, disease severity, and psychological variables with the ability to achieve higher final stimulation intensity. Methods: Women with fibromyalgia (N=143) were recruited for a dual-site randomized controlled trial – Fibromyalgia Activity Study with TENS (FAST). TENS electrodes and stimulation were applied to the lumbar area, and intensity was increased to sensory threshold (ST), then to “strong but comfortable” (SC1), then to “noxious” (N). This was followed by a reduction to the final stimulation intensity of “strong but comfortable” (SC2). We called this the Setting of Intensity of TENS (SIT) test. Results: There was a significant increase from SC1 (37.5 mA IQR: 35.6–39.0) to SC2 (39.2 mA IQR: 37.1–45.3) (p<0.0001) with a mean increase of 1.7 mA (95% CI: 1.5, 2.2). Linear regression analysis showed that those with the largest increase between SC1 and N had the largest increase in SC2–SC1. Further, those with older age and higher anxiety were able to achieve greater increases in intensity (SC2–SC1) using the SIT test. Conclusion: The SC2–SC1 increase was significantly associated with age and anxiety, with greater mean increases associated with older age and higher anxiety. Thus, although all patients may benefit from this protocol, older women and women with elevated anxiety receive the greatest benefit. Keywords: pain, transcutaneous electrical nerve stimulation, TENS, fibromyalgia, dosag