Screening of a microcirculatory bed in the dynamics of reparation of experimental extensive full-layer skin wounds

Abstract

Purpose of the study. The aim of our study was to determine the intensity of microcirculation in the area of ​​healing of a full-thickness wound in the skin of the frontal region of rats, to predict the speed and nature of the regenerative process using the Doppler method of regenerate tissues.

Materials and methods. The experiment was performed on 10 white outbred adult rats, which under ether anesthesia in the frontal area of ​​the front of the head were applied standard full-thickness skin wounds with an area of ​​100 mm2, which averaged 6% of the body area. A Doppler study of the microcirculation in the wound area was carried out using a Minimax – Dopler-K ultrasonic computerized instrument with a sensor operating at 25 MHz. The state of microcirculation was determined automatically using the software of the device.

Results. It is shown that the data of Doppler studies are fully correlated with the microscopic picture and the indices obtained with morphometry, which may indicate a qualitative change in the structures in the regenerate zone and the dependence of the wound healing rate on the blood flow intensity in the microvasculature. After 5 days, a significant number of microvessels and various cellular elements of tissue and hematogenous origin are found in the newly-formed granulation tissue, for 10 days the number of vessels increases, ensuring trophism of full-thickness skin regenerate, and then their regular reduction occurs. By 15 days, the defect area is completely covered by an even layer of the newly formed epithelium, under which there is a connective tissue scar component, in which the vessels are few, they are mostly located closer to the hypodermis, but they have a significant diameter and length, which is reflected in the increase in both linear and volumetric blood flow velocity.

Conclusion. The data of linear and volumetric blood flow rates in the microcirculatory bed of spontaneously regenerating wounds made it possible to identify indicators of the total cross section of microvessels and the amount of blood entering the regenerate area, which can be used to assess the nature of the effects of various stimulants of healing as a control. Doppler study allows to evaluate the course of all stages of the reparative process, to monitor the state of the microvasculature in the area of ​​the regenerate in the screening mode, to predict and correct the healing process .