Journal of Experimental and Clinical Surgery

The aim of the study was to investigate cytological features of healing processes in patients with soft tissue phlegmons using programmed sanitation technologies.
Materials and methods. The study involved 245 patients with purulent phlegmon of soft tissues of various localizations. The patients were randomized into two groups. The patients of the main group (n=127) were exposed to programmed sanitation with AMP-01 device in the postoperative period. After the phlegmon opening and surgical treatment, tubular drains were installed into the wound cavity, the wound was sutured tightly, and the drains were removed through separate incisions and connected to the device. The device was used to detect the parameters of sanitation (speed, time, volume during injection or aspiration). The patients of the comparison group (n=118) received conventional local treatment after surgery. The dynamics of the healing processes of purulent wounds was assessed by the cytological examination findings of the material taken during surface or puncture biopsy. 
Results. A higher rate of cellular reactions was registered in patients of the main group. There was a statistically significant faster decrease in degenerative forms of neutrophils, higher values of the regenerative-degenerative index (p<0.001) indicating an acceleration of the relief of the inflammatory process. In addition, in patients of the main group, the appearance of macrophages and fibroblasts (p<0.001) was statistically significantly observed at an earlier time, which evidenced a higher rate of proliferative processes; on the 9th day of the postoperative period the cytological picture corresponded to the regenerative type of cytograms. In patients of the comparison group, a prolonged inflammation and regeneration phase was recorded.
Conclusion. Cytological examination of smears in patients with soft tissue phlegmons exposed to programmed sanitation revealed a higher rate of cellular reactions, which contributed to a reduced inflammation phase and accelerated wound reparative processes.

Introduction. Liver resection remains the main trend in the treatment for primary and metastatic liver tumors and provides better overall and disease-free 5-year survival compared with conservative treatment options. Extensive liver resection is accompanied by the risk of post-resection liver failure. There is currently no absolute algorithm for determining the prognosis of post-resection liver failure. One of the ways to find new approaches to assessing the prognosis and diagnosing post-resection liver failure is bioimpedance analysis of the liver.
The aim of the study was to assess the effect of hepatic blood flow occlusion on changes in the electrical impedance of the liver and spleen.
Materials and methods. The study involved 20 male Wistar rats weighed 180-270 g. In the first series, experimental animals underwent occlusion of the hepatic blood flow for 15 minutes, and then underwent reperfusion (n=10). In the second series, occlusion of the hepatic blood flow was carried out for 90 minutes (n=10). Under general anesthesia, a median laparotomy was performed, followed by the application of a vascular clip to an analogue of the hepatoduodenal ligament, followed by clamping of the bile duct, hepatic artery and portal vein for 15 minutes in the first series and 90 minutes in the second series of the experiment. Invasive bioimpedansometry of the liver was performed using an original device for measuring the impedance of biological tissues BIM-II (RF patent No. 2366360). The data obtained were analysed at a frequency of 2 kHz, the hepatosplenic index (HSI) was calculated as the ratio of the average electrical impedance of the liver to the average electrical impedance of the spleen.
Results. The 1st series of experiments. After applying the clips to the hepatoduodenal ligament analogue, the value of the electrical impedance of the liver parenchyma at a frequency of 2 kHz did not change and amounted to 2.3 (2.11; 3.1) kΩ versus 2.34 (2.05; 2.81) kΩ registered before manipulation. The median spleen impedance decreased statistically significantly from 2.7 (2.07; 3.5) kΩ to 1.63 (1.47; 2.04) kΩ (p <0.05). After 15-minute occlusion of the hepatic blood flow, the electrical impedance of the liver parenchyma statistically significantly increased by 1.47 times and amounted to 3.98 (2.64; 4.59) kΩ. The median value of spleen impedance was 1.86 (1.52; 2.23) kΩ, and was statistically significantly lower (p<0.05) than before the clip application. After reperfusion, the liver impedance decreased to 3.11 (2.06; 5.11) kΩ, and the spleen impedance was 2.08 (1.53; 2.55) kΩ, while both parameters were statistically significantly different from the initial values. The dispersion coefficient D2kHz/20kHz of the liver statistically significantly increased to 2.10 (1.67; 2.58) 15 minutes after the clip application relative to the parameters before vascular exclusion – 1.71 (1.44; 2.08) and immediately after clamping analogue of the hepatoduodenal ligament – 1.60 (1.46; 2.11). After reperfusion, the dispersion coefficient D2kHz/20kHz of the liver parenchyma did not differ from the initial values and amounted to 1.79 (1.52; 2.29). The dispersion coefficient D2kHz/20kHz of the spleen decreased significantly immediately after occlusion of the hepatic blood flow from 1.54 (1.28; 1.71) to 1.36 (1.20; 1.62) and was at the corresponding level, including that after reperfusion. Fifteen minutes after the clip application, the dispersion coefficient D2kHz/20kHz of the spleen was statistically significantly lower than the values of D2kHz/20kHz of the liver (p<0.05) – 1.42 (1.19; 1.6) versus 2.1 (1.67; 2.58). Before vascular exclusion of the liver, the median HSI was 0.89 (0.72, 1.11). After the clip application, the HSI parameter statistically significantly increased to 1.43 (1.28; 1.95) due to a decreased electrical impedance in the spleen parenchyma. After 15-minute ischemia, HSI statistically significantly increased to 2.01 (1.26; 2.68), and after reperfusion it remained at a level higher than the initial level. 
The 2nd series of experiments. Before vascular exclusion, the electrical impedance of the liver parenchyma of experimental rats was 2.39 (1.8, 2.57) kΩ. After 15 minutes, the electrical impedance increased significantly to 3.2 (3.08; 3.32) kΩ, which was consistent with the results of the previous experiment. After 30, 45, 60 and 90 minutes, the impedance values of the liver parenchyma did not change and were increased if compared with the initial level. The coefficient of the electrical impedance dispersion of the liver increased statistically significantly after 15-minute ischemia and remained at a high level until the end of the experiment. After the clip application, the HSI parameter statistically significantly increased after 15 minutes and remained at a level higher than the initial level in 30 minutes, 45 minutes, 60 minutes, 90 minutes of ischemia.
Conclusions. After vascular exclusion of the liver, interrelated changes in the electrical impedance of the liver and spleen occurred within 15 minutes. These processes are mainly associated with changes in blood supply to the studied organs and ischemia effects.

Solitary fibrous tumor (SFT) is a rare neoplasm of mesenchymal origin characterised by NAB2 and STAT6 genes fusion. SFT occurs in one of 300.000 patients who seek medical attention. Incidence rate of liver SFT is unavailable due to a minor number of existing observations. In most cases, diagnosis of SFT is incidental. Yet, in 5% of cases, it manifests as paraneoplastic syndromes. Differential diagnosis using CT and MRI is complicated due to unspecific pattern of the neoplasm. This paper presents a clinical case of a 58-year-old patient who applied for a consultation at A.V. Vishnevsky National Medical Research Center of Surgery. Due to non-specificity, the laboratory and instrumental examination findings did not allow making a correct diagnosis at the preoperative stage. Histological examination findings helped to finally diagnose solitary fibrous tumor. Based on the data obtained, we can draw a conclusion about the imperfection of existing diagnostic options and the need to identify specific criteria for solitary fibrous tumor diagnosis.

As a research task, the authors attempted to assess factors affecting the results of the experiment involving laboratory animals in the perioperative period and the modes of their action. The perioperative period has a significant impact on the state of organ systems, in particular, and on the vital activity of the organism, as a whole. This paper describes the key points having an impact on successful surgical interventions. Particular attention is paid to the main groups of factors that affect the severity of perioperative complications - hypoxia, hypothermia, the use of pharmacological drugs, the human factor, the preparation of the animal for surgery, as well as the choice of anesthesia and the method of its administration. One of the reasons leading to the death of the operated animal is the failure of the sutures in the area of surgical intervention, which is often caused by the action of endogenous microorganisms in the area of the operation. The scientific novelty of the study lies in a systematic approach to the examined material accumulated as a result of numerous studies. Based on the results obtained, a list of groups of factors, their influence on the body, and ways to eliminate their role in the occurrence of perioperative complications was determined.