Haemodynamic substantiation of surgical treatment of elderly patients with varicose trophic ulcers

The dissertation is devoted to the investigation of peripheral macrohaemodynamics and microcirculation of tissues of distal segments of the lower extremities in elderly patients with varicose trophic ulcers in order to substantiate the tactics of complex treatment. It examines the epidemiology of venous trophic ulcers, modern concepts of their development, the role of macro- and microhaemodynamic disturbances, tissue hypoxia, aseptic inflammation, haemorheological disorders, lipid peroxidation and the cytokine profile. On the basis of a comprehensive clinical and instrumental examination and a comparison of the results of conservative therapy and different types of phlebectomy, criteria are formulated for the selection of a radical surgical intervention and for predicting the time of ulcer healing in elderly patients.

The practical significance of the work is associated with the development of a pathogenetic surgical approach that makes it possible to eliminate venous hypertension in distal segments of the extremity regardless of the area of the ulcerative defect and the prevalence of lipodermosclerosis, as well as with the substantiation of a regimen of complex conservative therapy in the pre- and postoperative periods aimed at correcting ischaemic disturbances in the microcirculation system and arresting aseptic inflammation.

Relevance of the problem

Venous trophic ulcers occur in the countries of Europe in 1.01–2.13% of the population (Bogachev V.Yu., 2003; Baccaglini U., 2000; Jawien A., 2003; Moffatt C.J., Franks P.J., 2004). In the Russian Federation, venous trophic ulcers occur in more than 2.5–3.0 million people (Savel'ev V.S. et al., 2002). In the working population, venous trophic ulcers of varicose origin occur considerably less frequently (0.1%) than in elderly patients, and in more than half of them the ulcers fail to heal for between 1 and 5 years (Kirienko A.I. et al., 2004; Levy E. et al., 2000; Pina E. et al., 2005). The total cost of treatment of venous trophic ulcers is extremely high: the cost of treating one patient in Europe and the United States reaches 10,000 dollars, and in Russia — 150,000 rubles (Savel'ev V.S. et al., 2001; Splawinski J., 2000).

At present, researchers have no unanimous opinion on the haemodynamic significance of individual blood refluxes in ulcer formation, although a large number of studies have been devoted to the investigation of macrohaemodynamic factors of the development of trophic disturbances in chronic venous insufficiency (Oganesyan G.K., 2001; Shval'b P.G., 2002; Zolotukhin I.A. et al., 2006; Zamboni P. et al., 2000; Mekkes J.R. et al., 2003).

Changes in microcirculation of the soft tissues of the lower extremities are the main link in the realisation of pathophysiological disturbances in chronic venous insufficiency. However, active investigation of the state of microcirculation in patients with venous trophic ulcers has become possible only in recent years, which is primarily associated with the introduction into clinical practice of clinical and metric methods of investigation: measurement of tissue partial pressure of oxygen and laser Doppler flowmetry (Koshkin V.M. et al., 2004; Carpentier P.H., 2000).

Haemodynamic substantiation of the complex treatment of elderly patients with venous trophic ulcers of varicose origin will make it possible to approach the solution of this problem at a new qualitative level and will provide the opportunity to predict the time of healing of trophic ulcers.

Aim of the work

Investigation of peripheral macrohaemodynamics and microcirculation of tissues of distal segments of the lower extremities in chronic venous insufficiency in order to formulate the tactics of complex treatment of elderly patients with varicose trophic ulcers.

Objectives of the investigation

1. To assess changes in arterial and venous peripheral haemodynamics in elderly patients with varicose trophic ulcers in the horizontal position and in orthostasis.

2. To investigate the state of microcirculation of soft tissues of the extremities in patients with CVI C6 according to CEAP and to determine pathognomonic features of changes in microhaemodynamics during the development of venous trophic ulcers of varicose origin.

3. To study and compare indicators of lipid peroxidation and the profile of opposing cytokine pools in patients with and without venous trophic ulcers.

4. On the basis of changes in peripheral macro- and microhaemodynamics after performing different types of phlebectomy, to identify radical surgical interventions in elderly patients with varicose trophic ulcers.

5. To determine the features of the state of microcirculation of tissues of distal segments of the extremity and to assess the profile of opposing cytokine pools in the early postoperative period in elderly patients with venous trophic ulcers.

6. To compare the data of the assessment of microcirculation of tissues of the lower extremities and the opposing cytokine pools in the preoperative and postoperative periods with the results of surgical interventions in patients with venous trophic ulcers in order to determine criteria for predicting the time of ulcer healing.

Scientific novelty

1. The trigger mechanism of the development of varicose trophic ulcers is high venous hydrostatic pressure, but the transition from lipodermosclerosis of tissues (CVI C4–5 according to CEAP) to an open venous ulcer of varicose origin occurs as a result of microcirculatory disturbance in the soft tissues of the extremity, and not of an additional change in haemodynamics in the large main vessels.

2. As a result of the investigations carried out, it was revealed that a characteristic feature of changes in microcirculation in CVI C6 according to CEAP is local tissue hypoxia in the lower third of the leg, manifested by a significant decrease in tissue partial pressure of oxygen in the zone of trophic ulcers, despite an increase in blood flow in the microcirculatory bed. Changes in microcirculation of the skin and subcutaneous fat in this category of elderly patients are also of a general character, associated with haemorheological disturbances and detected in different segments of the extremities.

3. For the first time, indicators of lipid peroxidation and the antioxidant defence system were investigated in venous blood obtained from three zones of the vascular bed with different levels of oxygen saturation (including blood obtained from the great saphenous vein in the ulcer zone), and an assessment of indicators of aseptic inflammation in the zone of trophic ulcers was carried out on the basis of determination of the cytokine profile in venous blood.

4. Characteristic features of the state of microcirculation of tissues of the lower extremities were noted in patients with venous trophic ulcers with an aseptic inflammatory reaction in the periulnar zone.

5. In patients with venous trophic ulcers, especially in patients with preoperative depression of microcirculation and pronounced tissue hypoxia in the periulnar zone, the development of a local "reperfusion" syndrome in the early postoperative period, which prevents ulcer regeneration, was revealed and investigated.

Practical significance

1. As a result of the ultrasound investigations performed, different variants of the prevalence of blood refluxes in the venous system of the lower extremities, leading to the development of phlebohypertension in elderly patients with venous trophic ulcers, were revealed.

2. For a reliable assessment of the functional reserve of microcirculation during laser Doppler flowmetry and transcutaneous polarography, the use of post-ischaemic and positional tests, which should be performed on distal segments of the extremity with a trophic ulcer and on the other extremity in the lower third of the leg, was substantiated.

3. A pathogenetic surgical approach in the treatment of patients with trophic ulcers has been worked out, which makes it possible to eliminate venous hypertension in distal segments of the extremity regardless of the area of the ulcerative defect and the prevalence of lipodermosclerosis on the leg.

4. The issues of complex conservative treatment of this category of patients in the pre- and postoperative periods, aimed at the correction of ischaemic disturbances in the microcirculation system and the arrest of aseptic tissue inflammation, have been refined.

5. In comparing the data of the assessment of microcirculation of tissues of the lower extremities and the dynamics of opposing cytokine pools in the pre- and postoperative periods with the results of surgical interventions in patients with venous trophic ulcers, criteria were developed for predicting the time of ulcer healing.

Implementation of the results of the investigation

The results of the investigation have been applied in practice in the work of the Department of Hospital Surgery of the Medical Faculty, the Department of Vascular Surgery of the 1st City Clinical Hospital of Saratov, and the Department of Functional Diagnostics of the Regional Polyclinic of the Regional Clinical Hospital.

On the basis of the materials of the work, methodological recommendations have been published for interns, trainees of the Department of Surgery of the Faculty of Advanced Training and Professional Retraining of Specialists, as well as for physicians of departments of functional diagnostics and angiosurgeons, "Assessment and Correction of Microcirculatory Changes in Patients with Trophic Venous Ulcers" (2006).

Approbation of the work

The main propositions of the dissertation were reported and discussed at the international conference "Haemorheology and Microcirculation" (Yaroslavl, 2003); the scientific and practical conference "New Technologies in Surgery" (Saratov, 2003); the scientific and practical conference "Methods of Investigation of Regional Blood Circulation and Microcirculation in the Clinic" (Saint Petersburg, 2003); the scientific and practical conference "Methods of Investigation of Regional Blood Circulation and Microcirculation in the Clinic" (Saint Petersburg, 2004); the All-Russian scientific conference "Microcirculation in Clinical Practice" (Moscow, 2004); the fifth scientific and practical conference "Methods of Investigation of Regional Blood Circulation and Microcirculation in the Clinic" (Saint Petersburg, 2005); the II All-Russian scientific conference "Microcirculation in Clinical Practice" (Moscow, 2006); the city scientific and practical conference with the participation of federal specialists "Topical Issues of Phlebology" (Saratov, 2006).

Main propositions submitted for defence

1. The basis for the formation of venous trophic ulcers in elderly patients with CVI is phlebohypertension, which is detected in 86.2% of patients already in the horizontal position and leads to disturbances of microcirculation in the soft tissues of the extremity. Changes in microcirculation in elderly patients with venous trophic ulcers are both of a local ischaemic character, detected in tissues of distal segments of the extremity, and of a general character — due to disturbance of the haemorheological properties of the blood.

2. In response to pronounced local tissue hypoxia in the zone of a trophic venous ulcer, processes of free-radical lipid peroxidation are activated, leading to systemic exhaustion with the development of cytokine-mediated damaging action on tissues of distal segments of the extremity.

3. On the basis of data from ultrasound methods of investigation, which allow assessment of valvular insufficiency of the superficial, perforating and deep veins, a radical type of phlebectomy can be chosen in all elderly patients with venous trophic ulcers.

4. Complex conservative therapy for patients with venous trophic ulcers of varicose origin should be carried out both in the preoperative period and for 2–4 months in the postoperative period, even despite epithelialisation of the ulcer.

Publications

On the topic of the dissertation, 13 works have been published, of which 7 in central press.

Volume and structure of the dissertation

The dissertation consists of an introduction, 4 chapters, a discussion, conclusions, practical recommendations and a bibliography (106 domestic and 142 foreign authors). The total volume of the dissertation is 176 pages, of which the text occupies 135 pages of typewritten text. The dissertation contains 21 tab