Postoperative air leakage, - alveolo-pleural fistula, is one of the most frequent and insidious complications in thoracic surgery and the main limiting factor in the early discharge of patients from the hospital [1, 2, 3]. After performing the main stage of lung surgery, the frequency of intraoperative verification of air leakage can be 25-75% [4]. As a rule, intraoperatively verified air leakage when checking for aerostasis after performing the main stage of the operation is often combined (up to 70%) with hemostasis failure. In this regard, many surgeries in their practice apply additional measures to strengthen the area of damaged lung tissue, aimed at eliminating these two manifestations. At the same time, such methods as coagulation, mechanical clipping, and stitching are not always effective in the presence of an extensive bleeding surface.

In this regard, the development of new biocompatible materials and the creation of specialized biomedical products from them is becoming a leading area of research and production at the present time.

Technologies are being sought for the creation of bio-artificial materials and organs, which are systems of materials of artificial or biological origin, including cells of tissue organs, or stimulating the regeneration of the corresponding cells in the implantation zone. Resorbable materials with high biocompatibility are in high demand [5,6]. The implants being developed in surgery, starting with filaments and meshes to the most complex devices for organ replacement, are aimed at creating biologically compatible materials for surgery. They can be divided into groups depending on the type of materials used: the body's own biological tissues, blood preparations and their fractions, animal tissue processing products, and preparations based on natural artificial polymers.

To date, adhesive coatings have been widely used in surgical practice [7]. Their use is associated with the need to have special equipment in the operating room, and operating surgeons and staff must know the technique of mixing its components. The rapid polymerization of the prepared preparation and the occurrence of an adhesive process in the application area explain the restrained attitude of surgeons toward the widespread introduction of such adhesive compositions in abdominal and thoracic surgery [8].

One of the directions of the search for funds for local aero- and hemostasis was the use of collagen and gelatin. Gelatin sponges are produced abroad under the names "Spongostan", "Gelfoam", etc. [9]. The experience of using such drugs has shown mixed effectiveness, especially in cases of blood clotting disorders, as well as the danger of renewed bleeding. In addition, biological films have an antigenic property, stimulate tissue reactions, and lead to increased adhesion processes. With massive, profuse bleeding, it shifts and "washes away" from the wound surface. The drug does not adhere well to an uneven wound surface due to the rigidity of collagen fibres.

Substances used in clinical practice for local strengthening of the damaged lung area are often characterized by insufficient effectiveness and unidirectional effects. Many of these coatings are made of biological materials (animal or plant origin), which causes their high antigenicity as well as destruction during thermal sterilization.

Thus, effective and reliable aerostasis in cases of lung tissue damage is an urgent and unresolved problem in lung surgery. There is an urgent need to develop new implants that are easy to use and devoid of the disadvantages described above.

The ideological basis for this dissertation research was the possibility of developing a new method for ensuring the tightness of sutures in lung surgery, namely, reducing the risk of such manifestations as failure of aero- and hemostasis. It should be noted that the proposed method has no analogues since the biological implant is not applied superficially on top of the damaged lung tissue but is injected directly into the lung parenchyma in the area of damage. A total of 275 patients with various lung pathologies requiring surgical treatment were included in the study. All patients were divided into two groups. In the main group, 131 patients in 2022–2023 had a new method of sealing sutures after performing the main stage of lung surgery. The comparison group included 144 patients with lung pathology comparable to the main group, operated on from 2019 to 2021, in whom additional measures were taken during intraoperative verification to eliminate the insolvency of aero- and (or) hemostasis by traditional methods.

The study covered three medical institutions: State Institution "Republican Specialized Scientific and Practical Medical Center for Surgery named after academician V Vakhidov: Department of Lung and Mediastinal Surgery: 86 (59.7%) patients in the comparison group and 79 (60.3%) in the main group; Andijan Branch of the Republican Scientific Center for Emergency Medical Care: 31 (21.5%) and 28 (21.4%) patients, respectively; Ferghana Branch of the Republican Scientific Center for Emergency Medical Care: 27 (18.8%) and 24 (18.3%) patients. More than 90% of patients in both groups were between the ages of 21 and 60; men in the groups were 52.8% and 55.7%, and women were 47.2% and 44.3%.

The largest number of operations were performed for echinococcosis of the lungs in the comparison group 60 (41.7%) and in the main group 73 (55.7%). Next in number were patients with pulmonary bullous emphysema: 43 (29.9%) and 26 (19.8%) patients, respectively. Pancyric pleurisy was verified in 16 (11.1%) and 6 (4.6%) patients. In other cases, patients with focal lesions such as tuberculosis, hamartoma, fibrochondroma, lung abscess, cases of complicated residual cavities after echinococcectomy (hemoptysis, bronchial fistula, suppuration), as well as patients who underwent lobectomy for cystic hypoplasia of the lung lobe or bronchiectasis complicated by pneumofibrosis, were operated on.

All cases of benign oncopathologies were confirmed after surgery by histological examination. According to the localization of the pathological process, the distribution was as follows: in the comparison group, pathology in the left lung was in 64 (44.4%) patients, in the right in 80 (55.6%) patients, and in the main group, 62 (47.3%) and 69 (52.7%) patients, respectively. The incidence of lobe lesions was approximately the same for the upper and lower lobes, while pathology was localized on the right in the middle lobe in only 3 (2.1%) and 4 (3.1%) patients, respectively.

Taking into account the fact that the developed method can be used for both open and video thoracoscopy operations, these two types of interventions were included in the study groups, and for a more objective analysis in the chapters with the results of their own research, the analysis was also distributed according to this factor. Open surgeries were performed in 93 (64.6%) patients in the comparison group and in 87 (66.4%) patients in the main group. Video thoracoscopic interventions were performed in 51 (35.4%) and 44 (33.6%) patients, respectively. Among the range of open operations, echinococcectomy, excision and suturing of the lung bull(s), marginal resection, and lobectomy were performed. Echinococcectomy from the lungs, excision and suturing of lung bullae(s), marginal resection, and lobectomy also took place during video thoracoscopy interventions (Table 1).

Table 1: Distribution of patients by type of surgical treatment.

In the main group, seam sealing was performed according to the proposed method, which is characterized by the following technical features: The main stage of the operation is performed, and then a gel is prepared: 1.0 g of Hemoben powder is mixed with 30 ml of saline solution with continuous stirring for 1 minute and immediately typed into a syringe with an injection needle with a diameter of 25–30 G. To achieve local aero- and hemostasis in damaged or sutured lung tissue, a needle injection is performed at a distance of 5 mm from the edge of the damaged lung parenchyma, and then the needle is moved superficially at a depth of 5 mm at an angle of 30 ° from the periphery (injection site) towards the center of the wound surface while 0.5–1.0 ml of Hemoben gel is injected. This procedure is repeated 3–4 times, depending on the volume of the wound surface, until the gel completely imbibes the entire wound defect (Fig. 1).

Multispiral Computed Tomography. Swollen Bull of the Upper Lobe of the Left Lung

                Prepared gel with Hemoben preparation                                        Needle for injection                                  

View of a bloated bull                                                                        Excision of the bull

                                Puncturing of the damaged lung parenchyma                                 Gel infiltrated lung tissue                                               

Figure 1: Sealing of the damaged lung area after excision of the bull of the upper lobe of the left lung using a new technique.

After holding a pause of 2-3 minutes, the lung is straightened with the supply of an oxygen-air mixture on inspiration. When additional places of air intake appear, the procedure for introducing Hemoben gel is repeated, while the depth of introduction of Hemoben gel should also not exceed 5 mm.

To analyze the effectiveness of the proposed technique in the intraoperative period, after performing the main stage of the operation, which consisted of marginal resection, lobectomy (with an unexpressed interlobular gap), excision, and suturing of the bull bed, as well as after echinococcectomy with partial pericystectomy and suturing of the residual cavity, a gel was intraparenchymatically injected into the area of the lung tissue defect.

Initially, after the main stage of the operation, the condition of the aerostasis was assessed. The simplest method for estimating the intensity of air leakage is the Macchiarini scale, which evaluates the failure of aerostasis as follows:

0 – no leakage, no visible leakage;

1 – Easy leakage, counted bubbles;

2 – Moderate leakage, bubble jet;

3 – Severe leakage, fused bubbles [12].

In the comparison group, immediately after the main stage of the operation, leakage was absent in 84 (58.3%) of 144 patients, in the main group, it was absent in 71 (54.2%) of 131 patients. Mild leakage, which does not require additional measures to eliminate it, was verified in 36 (25%) and 37 (28.2%) patients, respectively. Moderate air discharge was found in 15 cases in both groups (10.4% and 11.5%), and severe leakage in 9 (6.3%) and 8 (6.1%) patients, respectively.

In both groups, the initial aerostasis failure occurred at approximately the same frequency. The air discharge, taking into account the operation option, differed slightly, while it was noted that after video thoracoscopy of operations, the percentage of moderate and severe insolvency was insignificantly higher (by 4-5%). In the comparison group, after open operations, moderate discharge was in 9 (9.7%) of the 93 interventions; in the main group, in 9 (10.3%) patients, severe leakage was detected in 5 cases (5.4% and 5.7%) (Fig. 2). There was no discharge in 57 (61.3%) and 49 (56.3%), and the first degree was determined in 22 (23.7%) and 24 (27.6%) patients. After video thoracoscopy of operations, moderate discharge was detected in 6 (11.8%) and 6 (13.6%) patients, respectively, and severe leakage was found in 4 (7.8%) and 3 (6.8%) patients. Discharge was absent in 27 (52.9%) and 22 (50%) patients, and the first degree was identified in 14 (27.5%) and 13 (29.5%) patients.

Figure 2: Intraoperative assessment of the intensity of air leakage (Macchiarini P, 1999) in open and video thoracoscopy interventions.

In the main group, intraparenchymal puncturing of the lung parenchyma was performed during this period according to the proposed method, after which a re-assessment of the degree of air leakage was carried out. After pricking, leakage was already absent in 110 (84%) patients, mild leakage was verified in 16 (12.2%), moderate discharge occurred in 3 cases (2.3%), and severe leakage was detected only in 2 (1.5%) patients.

Taking into account the operation option, a significant difference was also obtained in terms of the degree of air leakage. After open operations immediately after pricking, leakage was already absent in 74 (85.1%), mild leakage was verified in 10 (11.5%), moderate air discharge occurred in 2 cases (2.3%), and severe leakage was detected only in 1 (1.1%) patient (χ2 = 17.967; df = 3; p<0.001 in relation to the situation before pricking). After video thoracoscopy of operations, moderate and severe discharge was detected in 1 case (2.3%), there was no discharge in 36 (81.8%), and the first degree was identified in 6 (13.6%) patients.

Summarizing the assessment of the degree of air leakage in the comparison groups, the following can be noted: In the comparison group, the absence or insignificant leakage (0–1 degrees), which did not require additional measures to ensure adequate aerostasis, was noted in 120 (83.3%) cases; in the remaining 24 (16.7%) cases, air leakage corresponded to 2-3 degrees. In the main group, before gel injection, these indicators were distributed among 108 (82.4%) and 23 (17.6%) patients. After performing the proposed method, the 0-1 degree in this group was 96.2% (126 patients), and the 2-3 degree was determined only in 3.8% (5 patients). The significance of the difference to the main group after pricking was χ2 = 12.956; df = 1; p<0.001 relative to the comparison group, and χ2 = 12.007; df = 1; p<0.001 relative to the main group before pricking.

In the comparison group, after open operations, absence or insignificant leakage (0–1 degree) was noted in 79 (84.9%) cases; in the remaining 14 (15.1%) cases, air leakage corresponded to 2-3 degrees (to the main group after piercing: χ2 = 7,079; df = 1; p = 0.008). In the main group before gel pricking, these indicators were 73 (83.9%) and 14 (16.1%) patients (in the main group after pricking, χ2 = 7,888; df = 1; p = 0.005). After performing the proposed method, the 0-1 degree was 96.6% in this group (84 patients), and the 2-3 degree was determined only in 3.4% (3 patients). After videothoracoscopy of operations in the comparison group 0-1, the degree of leakage was established in 41 (80.4%) patients, in 10 (19.6%) – 2-3 degrees (to the main group after piercing - χ2= 4.856; df = 1; p=0.028). In the main group before pricking, these indicators were 35 (79.5%) and 9 (20.5%), respectively (for the main group after pricking, χ2 = 5,091; df = 1; p = 0.025). After pricking, grade 0–1 was identified in 42 (95.5%) and grade 2–3 in only 2 (4.5%) patients.

An equally important aspect of parenchymal organ surgery is the local hemostasis consistency factor. In our observations, an isolated or combined hemostasis disorder after performing the main stage of surgery in the comparison group was detected in 23 patients (16% of 144 patients), of which 14 (15.1%) cases during open operations and 9 (17.6%) cases after videothoracoscopy of operations, which, as a result, turned out to be significantly higher than in the main group after Hemoben injection: only 4 (3.1% of 131 patients; χ2= 12.930; df = 1; p<0.001), with open and videothoracoscopy operations in 2 cases (2.3% of 87 patients; χ2= 8.828; df = 1; p= 0.003 and 4.5% of 44 patients; χ2= 3.960; df = 1; p= 0.047). At the same time, before pricking, the frequency of detected inadequate hemostasis in this group was 16.8% (in 22 patients; reliability to the main group after pricking was -2 = 13.834; df = 1; p<0.001), including open interventions in 13 (14.9%) cases and videothoracoscopy operations in 9 (20.5%) cases. Accordingly, the proportion of consistent hemostasis in the groups was 84% (121 cases) in the whole comparison group, 82.4% (42) in video thoracoscopy operations, and 84.9% (79) in open operations. In the main group, 83.2% (109 patients), 79.5% (35) and 85.1% (74) of cases, respectively, before the use of the new method, and after pricking, 96.9% (127), 95.5% (42) and 97.7% (85).

After performing the main stage of the operation, depending on the type of suture, 10 cases (12.8% of 78 patients) of inadequate hemostasis were detected in the comparison group, 13 (19.7% of 66 patients) with hardware stitching, and in the main group after Hemobene piercing, these indicators were only 1 (1.4% of 69 patients; χ2= 6,838; df = 1; p= 0.009) and 3 (4.8% of 62 patients; χ2= 6,453; df = 1; p= 0.012) cases. Before pricking, in the main group, the frequency of detected inadequate hemostasis was 11.6% (in 8 patients) after manual suturing of a lung wound and 14 (22.6%) cases after hardware stitching. Accordingly, the proportion of consistent hemostasis in the groups was 87.2% (68 cases) in the comparison group after manual suture and 80.3% (53) with hardware stitching. In the main group, 88.4% (61 patients) and 77.4% (48) before using the new method, and 98.6% (68) and 95.2% (59) after pricking.

Analysis of the combined incidence of local hemo- and aerostasis insolvency (significant leaks) verified after the main stage of the intervention showed that aerostasis-only insolvency in the comparison group was identified in 13 (9.0%) cases, in the main group before Hemoben infiltration, in 14 (10.7%) cases, and after performing a new method, in 3 (2.3%). The failure of hemostasis alone was determined in 12 (8.3%), 13 (9.9%), and 2 (1.5%) patients, respectively. Combined failure of aero- and hemostasis in 11 (7.6%), 9 (6.9%), and 2 (1.5%) patients. Adequate aero- and hemostasis was 75% (108 patients in the comparison group; χ2= 20,158; df = 3; p<0.001 in relation to the main group after pricking), 72.5% (95 patients in the main group before pricking; χ2= 23,479; df = 3; p<0.001), and 94.7% (124 patients in the main group after applying the new method) (Table 2).

Table 2: Summary frequency of local hemo- and aerostasis failures (significant leaks) verified after the main stage of the intervention.

All cases of significant aero- and/or hemostasis insolvency identified intraoperatively required additional measures to eliminate them. The options for eliminating these manifestations could be isolated or combined. Additional U-shaped sutures were effectively performed in 10 (6.9%) cases in the comparison group and in 2 (1.5%) patients in the main group. With signs of failure of aerostasis from the needle injection, no additional treatment of this type of insignificant air discharge was carried out, but active aspiration was not activated in these patients for 1-2 days. These terms are enough for the wound surface of the lung to be covered with fibrin, after which active aspiration was connected, and, in the absence of discharge, the first drainage from the pleural cavity was removed after 3 days, the second after another 1-2 days. It should be noted that in virtually all cases, drainage of the pleural cavity was carried out by two drains, with the exception of small resection video thoracoscopy interventions, in which only one drainage was installed (in 6 patients in the comparison group and 7 patients in the main group).

In the comparison group, Hemoben powder was applied over the lung wound in 8 (5.6%) cases and in the main group in 3 (2.3%) cases to achieve effective aero- and hemostasis. This technique was previously proposed at the State Institution "Republican Specialized Scientific and Practical Medical Center for Surgery named after academician V. Vakhidov."  In fact, the method is effective, which has been proven in clinical studies. However, to achieve an acceptable result using this method, a parietal pleura sheet is required on top of the applied Hemoben powder to strengthen the suture line and adhesion. Hemoben powder created conditions for tight fixation of the pleura to the lung parenchyma, which provided additional strengthening of the suture line.

After performing marginal resection in the comparison group, in 2 (1.4%) cases, due to the inability to achieve aerostasis with U-shaped sutures (the latter erupted), lobectomy was forcibly performed with a good clinical result. Also, in 4 (2.8%) cases in the comparison group, chemical pleurodesis with iodinol solution was performed to achieve aerostasis by local treatment of the damaged lung area to initiate aseptic inflammation, followed by obliteration of the parenchymal fistula.

A combination of different methods to achieve aero- and hemostasis was performed in 12 (8.3%) cases in the comparison group and in 2 (1.5%) patients in the main group. U-shaped sutures and the application of Hemobene powder were most often combined.

Summarizing the primary studies on intraoperative verification of the effectiveness of the proposed method of achieving aero- and hemostasis in lung surgery, the following can be noted: The introduction of the Hemoben gel composition into the lung parenchyma in the area of tissue damage to a depth of 5 mm reduced the need for additional manipulations to eliminate these manifestations from 25% (in 36 of 144 patients in the comparison group) to 5.3% (only in 7 of 131 patients in the main group). Thus, the proposed technique does not take much time, is easy to perform, and is not expensive, since on average only 1 vial of Hemoben (1.0 g) is consumed per operation, while it allows increasing the proportion of primary (after performing the main stage of the operation) adequate aero- and hemostasis from 75% to 94.7% (χ2 = 20,092; df = 1; p<0.001).

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