Effect of locally injected autologous platelet-rich plasma on second intention wound healing of acute full-thickness skin defects in dogs.

OBJECTIVES: Second intention wound healing may be impaired by wound and host factors and thus more advanced therapies are required for a fast and satisfactory outcome. Platelet-rich plasma (PRP), rich in growth factors and cytokines essential for tissue repair, could improve wound healing. The purpose of this experimental study was to evaluate the effect of locally injected autologous PRP on second intention healing of acute full-thickness skin defects in dogs. METHODS: Three 2 x 2 cm full-thickness skin defects were created bilaterally on the dorsolateral area of the trunk of six Beagle dogs. The wounds of one randomly selected side received PRP treatment, whereas the contralateral wounds were left untreated (controls). Wound healing was evaluated by planimetry, laser-Doppler flowmetry measurements of tissue perfusion, and histologically. RESULTS: The rate of wound healing did not differ significantly between the two groups. Tissue perfusion was significantly higher in the PRP-treated group (p = 0.008) compared to controls on day 10. Histological evaluation revealed a trend towards greater collagen production and a significantly better collagen orientation (p = 0.019) in PRP-treated wounds on day 20. CLINICAL SIGNIFICANCE: Locally injected autologous PRP does not accelerate the healing process, but increases tissue perfusion and may promote the formation of organized collagen bundles in acute full-thickness skin defects in dogs.

Locally injected autologous platelet-rich plasma enhanced tissue perfusion and improved survival of long subdermal plexus skin flaps in dogs.

OBJECTIVES: Distal flap necrosis remains a major complication in subdermal plexus (random) skin flaps. Platelet-rich plasma (PRP) has been shown to improve the survival of ischemic random skin flaps in rats. The objective of this study was to evaluate the effect of locally injected autologous PRP on the survival of long (5:1 length-to-width ratio) subdermal plexus skin flaps in dogs. METHODS: A 2x10 cm subdermal plexus skin flap was created bilaterally on the abdominal wall of six Beagle dogs. One randomly selected side received 2.5 ml of fresh auto-logous PRP injected evenly between sutures underneath the flap, whereas the other side was left untreated (control). Skin flap survival was evaluated macroscopically, histologically and by laser-Doppler flowmetry measurements of tissue perfusion. RESULTS: Flap percentage survival on day 10 (96.3% versus 74.5%; p = 0.046) and tissue perfusion (p <0.036) were significantly higher in PRP-treated flaps compared with controls. Histologically, there was less oedema in PRP-treated flaps compared to controls (p = 0.01), whereas collagen production and angiogenesis did not differ significantly between the two groups. CLINICAL SIGNIFICANCE: The use of locally injected autologous PRP increases tissue perfusion and improves the survival of long subdermal plexus skin flaps in dogs.

The wash-out technique in the management of delayed presentations of extravasation injuries.

Late presentation of extravasation injuries from chemotherapeutic agents is not uncommon. Twenty-four patients with extravasation injuries presented with upper limb extravasation but without any skin necrosis between the second and the fourteenth day following injury day. We flushed out the infiltrated area with 300-500 ml of normal saline through multiple stab incisions. All 24 patients responded well to the procedure and no further complications occurred. The average time for the complete healing of the wounds was 15 days. All the patients were able to continue their chemotherapy treatment without delay. Patients were followed up for a mean period of 13 months. They all recovered with no functional deficit and only mild scarring. Early recognition and immediate treatment of extravasation injuries are of paramount importance. In cases with no evidence of skin necrosis, a delayed wash-out procedure appears to be very effective in removing the extravasated drug and minimizing further tissue damage.