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PNV - Banter and General Comments, page-7780

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    I’m not surprised. There have been numerous published case studies and studies which suggest that time to delamination and grafting may take longer with BTM, either by necessity or by choice.

    Doctors in Cleveland, Ohio have published a couple of retrospective studies that compared outcomes in wound healing between BTM and CCS (Integra). One was is soft tissue wound healing (97 patients over a 5 year period). They noted significantly shorter time to skin grafting in the Integra group but attributed this to the fact that BTM was stable for a longer period of time. Clear advantages they found for BTM were lower rates of skin graft loss (with need for secondary procedures) and much cheaper cost.

    This study demonstrates similar rates of definitive wound closure and complications between CCS and BTM, with significantly lower rates of skin graft loss and need for secondary procedures in patients treated with BTM. Although the time to skin grafting was significantly shorter in the CCS group, this was not the result of more rapid incorporation or vascularization of the CCS but rather that BTM anecdotally has a longer window of time in which the substrate is stable before delamination of the sealing layer occurs and skin grafting is performed.



    Dr Kyle Chepla, a plastic surgeon in Cleveland, Ohio, states that one of the reasons he likes BTM better than other products is because he can leave it on “forever”. He explains that in the past, with other products, he was always worried about getting to graft as soon as possible because he was worried about losing the matrix.


    A recently published case report by plastic surgeons in Leicester, England, describes use of BTM in an extravasation injury to the foot and ankle. In this instance, Covid forced surgeons to wait 59 days before delamination could take place.

    Ordinarily, SSG can be applied to the BTM in the wound once there has been sufficient integration of the granulation tissue from the wound bed, which is typically around 3 weeks. In this patient, we feel clinically, application of SSG would have been appropriate from around 3 weeks after application of BTM. Unfortunately, return to theatre was delayed due to limited theatre access due to the COVID-19 pandemic. On day 59, the patient returned to theatre for delamination of the BTM, curettage debridement and application of a meshed split-thickness skin graft. Owing to the biodegradable nature, there was no issue with the delay to SSG application. By the time the patient returned to theatre, the BTM was fully integrated and even had some overgranulation.


    Dr Blome-Eberwein, from the Lehigh Valley Burn Center in Allentown, Pennsylvania, says that she has left the BTM for up to two and a half months but that it could be left even longer if necessary. In contrast, she has described Integra and other biologics “melting” (i.e disintegrating), resulting in loss of the matrix.


    In the paper published following the CE Mark burns trial, which was discussed here yesterday, it was also noted that time to skin grafting with BTM took longer than times reported in published studies of Integra.

    In the setting of major burn injuries, mean duration from application of BTM to skin grafting in this study was 31.9 days. Approximately four weeks seems to be necessary prior to delamination and grafting. However, extent of burn injury, patient medical status and donor site availability for autologous grafting may have also contributed to timing of delamination and grafting, and BTM may have been assessed as integrated at an earlier time.

    The two-stage approach and four weeks delay in permanent wound closure is arguably a disadvantage of BTM. However, with forward planning and strategic application of this matrix, this delay is actually an advantage when donor sites are inadequate in the major burn setting. The BTM acts as an effective wound temporiser whilst donor sites heal and become available for further re-cropping. Delamination and grafting has been previously delayed up to 47 days after BTM application [3]. This provides flexibility for the surgeon and the ability for the treatment course of individual patients to be taken into consideration, rather than being driven by the characteristics of the device. It also highlights the importance of patient selection.


    Finally, the esteemed Professor John Greenwood is of the view that earlier skin grafting in the case of major burns is deleterious rather than beneficial.

    We realised that, if graft applied over BTM five weeks after graft applied to debrided burn is softer, more elastic and cosmetically superior, and not just in the short term but also after several years, then early grafting is not only unnecessary, it is deleterious.
    The shift in our major burn protocol was immediate….


    Previously, we had harvested autograft as early as possible to commence definitive wound closure. This coincided with the patient being at their sickest and physiologically most vulnerable.

    Early grafting resulted in longer initial surgeries and prolonged anaesthesia. The patient’s wounds were iatrogenically expanded, adding further early physiological insult. The postoperative pain and patient status created the tendency for them to remain on the intensive care unit longer.


    Various different views, but clearly there are many surgeons who don’t perceive earlier grafting to necessarily be an advantage.
 
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