Adequate perfusion of tissues is a prerequisite for satisfactory healing of wounds, in particular in the case of fractures of the foot and Achilles tendon injuries. The high rate of wound healing process disorders, infections and pseudo-arthrosis reflects on restrictions often present in microcirculation in the area of injury. This is due to a limited anatomical vascular circulation of the tarsal bones as well as resulting tissue damage (dislocation, haemorrhage, oedema, contamination etc.) and is furthermore influenced by individual patient factors and surgically-related trauma.
The use of hyperbaric oxygen therapy in treatment and follow-up treatments is therefore considered as very promising because of its many positive effects. However, little is known on the precise impact of HBO on microcirculatory parameters.
In order to evaluate the circulation of blood in the foot and the influence of hyperbaric oxygen on microcirculation, it is intended to prepare the mapping of specific measurement points of a healthy foot.
By using the O2C unit (laser Doppler / white light spectroscopy: “oxygen to see”; LEA Medizintechnik GmbH), measurements are intended on the microcirculatory parameters of 40 healthy volunteers. Items to be considered are the oxygen saturation of haemoglobin, relative haemoglobin numbers, relative blood flow and blood flow velocity. A special area of interest are anatomically defined segments of the calcaneus and the talus, the Achilles tendon and soft tissue areas, which need to be incised for common calcaneus access paths (lateral L-incision, Palmer, McReynolds). The study makes use of a surface probe (2 mm and 8 mm depth) and a deep probe (15 mm depth). In total 31 measuring points are recorded on the right foot.
The objective is to identify standard values for microcirculation based on a series of native measurements. This will then provide the basis for future early detection of threatening or existing wound complications in order to allow therapy. In addition, limits would be available to help identify the best access path for surgical intervention on a case-by-case basis.
In order to be in the position to investigate the influence of HBO treatment on microcirculation (initially on volunteers, later on patients), a second series is planned directly after HBO treatment (90 minutes at 1.4 bar hyperbaric pressure).
Contact: PD Dr. med. M. Knobe, Klinik für Unfallchirurgie Uniklinik RWTH Aachen