Does exercise influence burn-induced inflammation: A cross-over randomised controlled feasibility trial.

BACKGROUND: Burn injuries trigger a greater and more persistent inflammatory response than other trauma cases. Exercise has been shown to positively influence inflammation in healthy and diseased populations, however little is known about the latent effect of exercise on chronic inflammation in burn injured patients. The aims of the pilot study were to assess the feasibility of implementing a long duration exercise training program, in burn injured individuals including learnings associated with conducting a clinical trial in COVID-19 pandemic. METHODS: Fifteen participants with a burn injury between 5-20% total body surface area acquired greater than a year ago were randomised in a within-subject designed study, into one of two conditions, exercise-control or control-exercise. The exercise condition consisted of six weeks of resistance and cardiovascular exercises, completed remotely or supervised in a hospital gym. A comprehensive outcome measurement was completed at the initial, mid and end point of each exercise and control condition. To determine the success of implementation, the feasibility indicator for the data completeness across the comprehensive outcome battery was set at 80%. RESULTS: Half (49%) of eligible participants in the timeframe, were recruited and commenced the study. Six participants withdrew prior to completion and a total of 15 participants completed the study. Eight participants were randomised to the exercise-control and seven to the control exercise group. Five participants trained remotely and seven did supervised training. Three participants completed a mix of both supervised and remote training initiated due to COVID restrictions. Outcome measures were completed on 97% of protocolised occasions and 100% of participants completed the exercise training. CONCLUSIONS: Conducting a long duration exercise training study on burn injured individuals is feasible using the described methods. The knowledge gained helps improve the methodology in larger-scale projects. Insights into the impact of COVID-19 on this clinical trial and success enhancing adaptations for the researcher, research practice and the participant, are presented.

An objective measure for the assessment and management of fluid shifts in acute major burns.

BACKGROUND: Major burns are life threatening. Fluid resuscitation is required for survival to maintain intravascular volumes and prevent hypovolemic shock. Bioimpedance spectroscopy (BIS) has been recognised as a potential method of monitoring fluid shifts after burn and in other disease states. The aims of this study were to examine the reliability of BIS across different dressing conditions and electrode positions, establish the influence of Acticoat™ on BIS variable measures and determine the validity of whole-body BIS to assess net fluid shift in the presence of moderate to major burns. METHODS: An observational longitudinal cohort study was conducted from December 2014 to February 2016. Patients with over 15% total body surface area (TBSA) burns and injury less than 48 h were enrolled in the study. BIS triplicate measures were collected in an open wound and with an ActicoatTM dressing (at 5 half hour intervals). Standard and alternate electrode placements were utilised for the reliability analysis and standard placement only for determining the validity of BIS in moderate to major burns. The ImpediMde SFB7 was used to collect whole-body and segmental BIS measures. Stata statistical software, release 14 was utilised to analyse all results. Descriptive analyses were performed and were reported using the means and standard deviations (SD). RESULTS: BIS-repeated measures established BIS raw resistance (R), and predicted volume variables were reliable in any condition (intra-class correlation coefficient (ICC) 0.996-0.999, 95% confidence intervals (CI) 0.996-0.999) without a systematic difference. Acticoat™ dressings significantly influenced all BIS-predicted volumes (p ≤ 0.01) as determined by multilevel mixed effects (MLME) linear regression analysis. Validity of BIS was demonstrated by resistance variables significantly decreasing with increasing net ionic fluid shift and increased TBSA (severity of injury) and calculated fluid volumes increasing with increasing net fluid shift and TBSA. BIS resistance also decreased with time as oedema reduced. For clinical use, a calculator was developed to adjust BIS variables when an Acticoat™ dressing is in situ, thus facilitating BIS variable change estimates in real time, with dressings intact. CONCLUSION: BIS may be used clinically to monitor fluid volume change in major acute burns.

Monitoring wound healing in minor burns-A novel approach.

Assessment of minor burn wound closure is predominately determined by visual inspection and clinical specialist assessment, which remains largely a subjective analysis and results may vary depending on the clinician's experience. Bioimpedance spectroscopy (BIS) is an instrument that has a demonstrated ability to objectively monitor the wound healing process in various patient populations but has not yet been used in acute burn wounds. The aim of the pilot study was to examine whether the BIS technique is a valid measure of wound healing. Localised BIS resistance and phase angle triplicate measures, of minor limb burns, were collected on two serial occasions. Circumference limb measures were taken at the localised burn site to determine a truncated limb volume. Proportional-odds ordered logistic regression analyses determined resistance at zero frequency (R0, indicative of edema) and resistance of total body fluid (Rinf) were significantly associated with healing after adjustment for the influence of surgery. A one unit increase in R0 and Rinf increased the odds of wound healing by 6% and 5% respectively (p<0.01). Phase angle at 50kHz and Ri were not significantly associated with the markers of the wound healing process. Spearman's correlation determined there was a significant association between a healing wound and limb segment volume (ml) (rho -0.30, p<0.01). BIS is a technique, which has the potential to monitor the progress of wound healing.

Bioimpedance spectroscopy: A technique to monitor interventions for swelling in minor burns.

The control of edema in burn injured patients is a priority as it can impede the wound healing process. Bioimpedance spectroscopy (BIS) has been identified as a method of swelling assessment that has merit after burns. The aim of this study was to examine the reliability and validity of BIS in the measurement of localised burn wound edema across (1) different dressing conditions (no dressing, non silver and silver dressings) and (2) three electrode positions. BIS resistance (R) was hypothesised to be inversely proportional to fluid (edema) volume. BIS was collected in triplicate for all conditions of interest. BIS repeated measures demonstrated excellent concordance for all BIS resistance variables (R0, Ri, Rinf) (intraclass correlation coefficient=0.999-1.00, 95% confidence intervals 0.999-1.00) without a systematic difference. Multilevel mixed effects linear regression analysis examined the effect of electrode position and dressing condition on BIS resistance variables. R0, Ri and Rinf significantly increased with decreasing localised limb segment volume (p≤0.01). Resistance was significantly (1) reduced when a silver dressing was in situ (p<0.01) and (2) increased when a non-silver dressing was insitu (p<0.01). There was a significant interaction between each dressing condition and localised limb segment volume (p<0.01). An algorithm was developed to adjust resistance values when a silver dressing is in use. BIS may be used clinically to monitor localised changes in burn wound edema.

Addressing the Barriers to Bioimpedance Spectroscopy Use in Major Burns: Alternate Electrode Placement.

Bioimpedance spectroscopy (BIS) is a method used to assess body composition and fluid distribution. As a technology for measurement of fluid shifts during acute burn resuscitation, there are potential barriers to its use due to the location of wounds. This study aimed to determine whether alternate electrode positions were a suitable alternative compared to standardized (manufacturer) positions in moderate to large size burns for the measurement of BIS resistance and fluid changes. BIS measurements were collected in standard and alternate electrode placements and in an open wound and Acticoat™ dressing condition. A percentage difference greater than 5% between each standard and alternate placement BIS measurements was deemed clinically significant. Chi-square tests determined there were no significant differences (P = .097-.96) between the standard and alternate electrode placements for whole body and limb segment BIS in both dressing conditions. Only whole body BIS resistance variables and extracellular fluid volumes were interchangeable in both dressing conditions and upper limb segmental measures were interchangeable in an open wound only. The differences between measurements of other BIS variables across the conditions were not acceptable or deemed not clinically acceptable without adjustment. The results showed that for moderate to large burn injuries clinicians can use whole body and upper limb segmental BIS variables to monitor changes in fluid shifts with alternate electrode placements where wounds preclude standardized placement within specified dressing conditions.

Nanocrystalline silver dressings significantly influence bioimpedance spectroscopy measurements of fluid volumes in burns patients.

Bioimpedance spectroscopy (BIS) is a tool utilized in health care to investigate body composition and fluid distribution. Limited research has addressed the clinical use of BIS in burns. This study aimed to examine the effects of silver dressings on BIS measurements in burns patients. BIS measurements were collected during two dressing conditions: no dressing (ND), and; Acticoat™ dressing (AD). Wilcoxon sign-ranks tests determined if there were any significant differences in BIS measures between the dressing conditions. Multilevel mixed-effects linear regressions examined the effect of %TBSA and body mass on BIS variables across the dressing conditions. The mean age of the patients (n=31) was 34.90 years; with a median TBSA of 15%. There was a significant increase in extracellular fluid (ECF) (p<0.001), intracellular fluid (ICF) (p<0.001) and total body water (TBW) (p<0.001) when AD was in place. There were significant interactions between dressing condition, %TBSA and body mass, whereby the difference in ECF, ICF and TBW between the ND and AD conditions were increased as %TBSA and body mass increased. Algorithms were developed subsequently to adjust BIS outputs for use when AD is in place. Clinician's may continue to use BIS in real-time using the predictive algorithms established during this study.