The percentage of body area burnt is considered a key tool in the management of patients with burns. Curently, there is no general consensus on which method of estimation is the most effective in pre-hospital care.
This literature review was conducted in 2016 to identify the most accurate methods of burn size calculation for the pre-hospital environment. The author carried out a systematic search of three large databases (MEDLINE, AMED and CINAHL) using well-specified search terms. The clearly presented search strategy section includes a table identifying the number of results for each search, which culminates in a total of 6535 papers. These were then further assessed against inclusion/exclusion criteria which ultimately eliminated all of these papers.
The author subsequently altered the search strategy to include all text fields on EBSCOhost, MEDLINE and COCHRANE, and used structured hand searching and citation tracking of publications and journals, as well as validation studies for new technology and non-burn specific papers relevant to assessment of percentage body areas. The search was further widened by removing the restriction on publication date and from this, 14 papers were deemed clinically relevant.
The author undertook a thematic analysis (however the actual process is not documented in the core paper) and four key themes emerged from this activity.
Theme 1: ‘Palm surface DOES NOT equate to 1% of total body surface area’
There was uncertainty between operators whether the digits should be included, or not, with the palm when calculating surface area. The review concluded that palmar surface area excluding digits does not equate to 1% of total body surface area, but more accurately represents 0.5% of total body surface area; whereas palm plus digits represents 0.8% but this may need to be adjusted for gender and/or obese patients.
Theme 2: ‘Expertise and experience greatly increase accuracy although can be further improved with clinical aids’
Overall, the papers indicated that experience and expertise greatly increase accuracy of estimating extent of burns by visual methods. However, it is identified that the use of charts or smart phone apps by both novices and experts can improve accuracy even further.
Theme 3: ‘Lund and Browder is currently accepted as the gold standard for assessment’
The review reinforced that Lund and Browder charts are still the ‘gold standard’ in terms of burns assessment, providing an accurate method of estimating surface area. However, it is shown to be time-consuming and with limited relevance to pre-hospital staff, whereas Wallace's Rule of Nines is simpler, quicker and accurate (within 3% of Lund and Bower) for pre-hospital purposes.
Theme 4: ‘Computer-aided calculation can greatly increase accuracy’
Availability of relevant computer-aided assessment tools is increasing but clearly there is room for more research to assess their efficacy. Early research on use of iPhone apps show a decreased assessment time and increased confidence and accuracy in inexperienced clinicians, however, no validation data was available.
Overall, this is a relevant and useful paper for ambulance clinicians. However, the author recognises that this review focuses solely on external body surface area and that consideration should be given to internal injuries.
Conclusions from the review indicate that using the patient's palm including digits multiplied by 0.8 may be appropriate for assessing minor burns as this is quick and easy to implement, and this may be more useful for inexperienced clinicians. It was recommended that Wallace's Rule of Nines be used for larger burns due to its ease of use and familiarity in the pre-hospital environment. The author identifies that further research is needed into this area with some consideration as to whether this tool should be incorporated into UK Ambulance Services Clinical Practice Guidelines Pocket Book to further increase clinicians' familiarity with this approach. With growing dependence on technology, research is needed on the accuracy and use of smart phone apps due to the lack of current validation data.
Current recommendations in the 2016 UK Ambulance Services Clinical Practice Guidelines advocate the use of Wallace's Rule of Nines for adult patients (not suitable for children under 14 years of age due to different body proportions to those of an adult) or Lund and Browder; and the Lund and Browder Paediatric Chart or other local guidelines for children under 14 (Association of Ambulance Chief Executives and the Joint Royal Colleges Ambulance Liaison Committee, 2016). Overall, it is interesting to note that there is a dearth of studies examining pre-hospital clinicians' competence and confidence estimating or calculating burn size, emphasising the need for further research into this important area of pre-hospital care.