RU2847956C1 - Method for treating infected wounds that are difficult to heal using platelet-rich plasma (prp) - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, in particular to purulent surgery, and can be used to treat infected, difficult-to-heal wounds using platelet-enriched plasma. The wound is cleaned, after which autotransplantation is performed by irrigating the wound surface with PRP no later than 10 minutes after its collection. Then, aloe extract and amorphous hydrogel are applied sequentially to the entire surface of the wound, repeating the procedure every three days for 28 days.

EFFECT: prevention of autotransplant dehydration by forming the necessary concentration of fibrinogen, fibronectin, and vitronectin in the wound and ensuring cell adhesion to the connective tissue and epithelial matrix.

1 dwg, 1 ex

Description

The invention relates to medicine, specifically surgery, and concerns the treatment of difficult-to-heal infected wounds. Treatment of such wounds is complicated by numerous factors, including their etiology, development, and the nature of the inflammatory and reparative processes. In surgical practice, purulent wound infections account for a significant proportion (35-45%), including in outpatient settings.

In recent years, platelet-rich plasma (PRP) has become widely used to treat chronic infected wounds. This technique promotes localized improvement in the biological condition of tissues. PRP is internationally recognized as an effective modern treatment method. Small doses of platelet-rich plasma contain significant concentrations, 2-8 times higher than those of intact whole blood. This material is widely used in regenerative medicine because it accelerates cell division and differentiation and promotes tissue restructuring in the wound area. Furthermore, fibroblast synthesis is enhanced, significantly improving the healing processes necessary for complete tissue regeneration. Furthermore, platelet-rich plasma is known to reduce inflammation caused by wound infection through cytokines. Autologous transplantation of these cells improves the survival of newly formed regenerates by normalizing the structure of the basement membrane.

However, using this method in infected wounds is not very effective. Numerous studies have shown that one of the reasons for this ineffectiveness is the changing microflora of purulent infections with increasing antibiotic resistance, the development of secondary immunodeficiencies, and widespread allergy in the population. Modern antibacterial drugs often have low resistance to precipitation and aggregation, which can lead to their inactivation upon contact with wound secretions. Furthermore, they can cause allergic reactions and are highly toxic to human cells, forcing clinicians to expand their arsenal of treatment methods and tools.

Therefore, the need to develop new antiseptic and biomodeling agents, their combinations, as well as to study their impact on the microbial composition of the wound and healing time becomes obvious.

A method for treating trophic ulcers uses autologous platelet-rich components (patent no. 1170912, September 28, 2012). To obtain platelet-rich plasma, 6 ml of the patient's blood are collected in sterile tubes containing 1 ml of 3.8% sodium citrate solution. The tubes are centrifuged for 10 minutes at 3000 rpm, after which the blood separates into three layers. The middle layer is collected in a separate sterile tube and used for ulcer treatment.

The disadvantage of this method is that with a single centrifugation in this mode, the concentration of platelets in the layer remains below 1,000,000/μl, which is insufficient to activate regenerative processes in the wound, and the applied platelet-rich plasma (PRP) dehydrates on the wound surface of ulcers.

A known method for treating chronic wounds (patent no. 2627814, August 11, 2017) involves covering the wound with a bioplastic membrane and securing it with sutures. A catheter is inserted under the membrane for daily administration of platelet-rich plasma obtained from the patient's blood. A disadvantage of this method is the high traumatic nature of the membrane, as it requires suturing, and the membrane's lack of antimicrobial properties.

A known method for treating chronic ulcers of various etiologies (patent for invention No. 2543344 dated February 27, 2015) uses autologous serum obtained from 20-25 ml of pre-centrifuged blood. The edges and base of the wound are injected with autologous serum, and a protein-platelet clot is applied to the wound surface. The procedure was repeated up to 20 times at two-day intervals. The disadvantages of this method include the fact that such repeated administration of autologous serum with dressings disrupts the integrity of granulation tissue, increasing the risk of wound infection. Furthermore, although the dressing prevents the preparation from drying out, it lacks antimicrobial activity, which can lead to infectious complications in the wound.

A known method for enhancing the antimicrobial activity of liquid aloe vera extract (patent no. 2796814, dated May 29, 2023) involves layering aloe extract and hydrosorb gel. However, this method does not stimulate reparative healing and serves only as a preparatory step for treating infected wounds to prevent dehydration of the product.

The purpose of this invention is to increase the effectiveness of treatment of difficult-to-heal soft tissue defects.

To achieve this goal, a method for treating infected, difficult-to-heal wounds using platelet-rich plasma (PRP) has been developed, the objectives of which are:

1. To modernize the method of treating infected, difficult-to-heal soft tissue defects;

2. Accelerate and improve the formation of regenerates in soft tissue defects;

3. To resolve issues of dehydration of platelet-rich plasma (PRP) from the wound surface to avoid complications;

4. Develop a technical method for applying a combination of platelet-rich plasma (PRP) and drugs to the wound, thereby reducing the indications for reconstructive interventions.

The method is performed as follows. First, 10 ml of blood is collected from the patient's peripheral vein and centrifuged for 15 minutes at 4000 rpm. The liquid portion of the plasma is then placed in a sterile tube without a stabilizer and centrifuged again at 3500 rpm for 15 minutes, yielding up to 2 ml of platelet-rich plasma. The non-viable edges of the wound are then excised, and debridement, if present, is performed. The platelet-rich plasma is applied uniformly over the entire wound by irrigation no later than 10 minutes after its collection, followed by layered application of aloe extract (336 mg/ml) and amorphous Hydrosorb gel over the entire soft tissue defect to protect the plasma from dehydration of the autograft. The procedure of administering platelet-rich autoplasma with layered application is repeated every three days for 28 days.

This effect is achieved because platelet-rich plasma promotes the creation of a sufficient concentration of biologically active substances in the affected tissue: fibrinogen, fibronectin, and vitronectin, which act as cellular adhesion molecules for the connective tissue matrix and epithelium. Other proteins found in alpha granules include platelet factor 4 (PF4), interleukin-1, platelet-derived angiogenesis factor, platelet-induced endothelial growth factor, insulin-like growth factor (IGF-1), and thrombospondin-1, which enhance healing.

The combination of platelet-rich plasma (PRP), aloe extract, and Hydrosorb gel exhibits antimicrobial activity through cytokines, growth factors, and proteolytic enzymes of the plasminogen group, which are found in platelet-rich plasma (PRP), providing a source of biologically active substances. Layered application of Hydrosorb gel and aloe extract prevents dehydration of the autograft from the surface of a soft tissue defect that is difficult to heal, a key advantage, as it allows the plasma to exert its reparative properties for longer by reducing its antimicrobial activity.

Clinical example.

Patient H., 62, was admitted on August 28, 2023, as an emergency patient with an infected trophic ulcer. She had suffered from trophic ulcers for 1.5 years, and the infection had developed within the last 5 days. Her comorbidities included hypertension and grade 2 obesity. Despite courses of rheological therapy and the use of a wide range of dressings, the ulcer continued to increase in size, and the patient developed constant, debilitating pain in the ulcer area. Upon examination, the patient's condition was moderate, and the ulcers measured 3.5 x 2.5 cm on the left leg and 3 x 1.5 cm on the right leg, with uneven depths of up to 3 mm each and jagged edges. At the ulcer base, there were sparse, flaccid granulations and areas of necrosis covered with fibrin, with moderate purulent discharge. The patient underwent a duplex ultrasound scan of the lower extremity vessels, which revealed no pathology in the major arteries or veins. She underwent a course of topical treatment for ulcers on her right and left shins. The procedure involved staged dressing changes every 3 days. Initially, the defects in the shin area were irrigated with PRP autologous plasma, followed by a layer of aloe extract, followed by a continuous layer of Hydrosorb gel, followed by application of an aseptic dressing and elastic bandage. This topical treatment had a gentle, anti-traumatic effect on the wound surface and surrounding skin, promoting optimal healing and epithelialization of the wounds. By the third week, the patient noted a persistent reduction in pain in the area of the skin defects, and by the eighth week, pain had completely disappeared, along with ulcer epithelialization. Blood pressure remained normal throughout the treatment. One month after the treatment, the patient showed no signs of pain, swelling, or other complications, and the ulcers on her right and left shins had completely healed, forming a permanent scar (Fig. 1). She was examined 12 months later. She has no complaints.

Claims (1)

A method for treating infected, difficult-to-heal wounds using platelet-rich plasma (PRP), including wound debridement, characterized in that autotransplantation of PRP is performed no later than 10 minutes after its receipt and autotransplantation is carried out by irrigating the wound surface with PRP, followed by sequential application of aloe extract with a density of 336 mg/ml and amorphous hydrosorb gel over the entire surface of the wound to the treated surface, repeating the procedure every three days for 28 days.