The New Approach to the Diagnostics and Treatment of Endogenous Intoxication in Patients with Burn Injury

Background: The main causes of mortality in patients with burn injury are the development of systemic inflammatory process, multiple organ failure and septic complications. The aim of the research: Improvement of diagnostic and therapeutic approaches to the detection and elimination of endogenous intoxication in patients with burn injury. Materials and methods: The main study group consisted of 19 patients and the comparison group—of 10 patients with burn injury. 92 blood serum (BS) samples of the patients of the main group were tested, using the method of fluorescence spectroscopy (MFS). The advanced therapeutic tactics were proposed for the patients of both groups. The control group consisted of 40 healthy individuals (donors). BS of these patients was also tested using MFS. Results: Patients with burn injury have endogenous intoxication in their blood. The effective concentration of albumin is reduced in patients with burn injury due to the blockage of albumin binding centers by bacterial metabolism products. Fluorescence spec-tra (FS) of BS in patients with burn trauma and donors were obtained and investigated. Based on MFS results, an improved treatment regimen using infusion of albumin solution was proposed. Conclusions: An improved tech-nique for the management of patients with burn injury is based on the use of MFS for the diagnostic blood test, bacterioscopic ex-amination), ultrasonographic


Introduction
According to WHO, the problem of burn injury is currently one of the most global in the field of health care. It is estimated, that up to 180,000 burn deaths occur annually in the world, most of which occur in low-and middle-income countries, including Africa, South and East Asia. The mortality rate of infant patients with burn injuries is over 7 times higher in low-income countries than in highly developed countries. Burn injury is one of the main causes of morbidity, leading to prolonged hospitalization, distortion and disability, and is often accompanied by stigma and rejection. This is especially true for patients with head and neck burns [1] [2]. Therefore, the problem of burn injury causes a number of serious economic, social and psychological problems and requires the development of effective methods of medical and social rehabilitation of patients.
Despite the introduction into medical practice the modern achievements of resuscitation, the latest methods of intensive care, the incidence of multiple organ failure, septic complications and mortality among patients with common burns remain quite high [3]. The main factors of mortality are the development of systemic inflammatory process, multiple organ failure and infectious complications [3]. The fraction of deaths from burn disease in the stage of burn shock is 23% -39%, in the stage of acute burn toxemia-35% -42%, and in the stage of septicotoxemia-25% -30%.
At the same time, a number of important theoretical and practical problems remain studied insufficiently. Also, the controversial are the issues about the radicality of early surgical interventions in patients with head and face burns, the extent and time of their performance, the means of plastic wound closure and the correction of general homeostasis disorders. The role of local and general disorders, characterizing the severity of traumatic injury, is also described insufficiently.
Therefore, the problem of recovery and survival of patients with burn injury is currently very relevant, important and not enough resolved. Therefore, many scientific researchers are devoted to this problem. However, insufficient attention was focused on assessing the prognosis for the development of purulent-septic complications in patients with burn injury and for their early diagnosis capabilities, especially monitoring and treatment.
In order to develop the pathogenetic approach of diagnosis, monitoring, management of the treatment process and prognosis, it is promising to use physical research methods, in particular MFS. Its high diagnostic value, accuracy and sensitivity makes it possible to build the concept of diagnostics, monitoring and elimination of endogenous intoxication in patients with burn trauma, which International Journal of Clinical Medicine will significantly improve the survival and recovery of patients with burn injury.

Literature Review
The immediate cause of lethality in patients with severe burns is purulent-septic complications, which appear from damage of many organs and systems during the development of severe burn disease and septicotoxemia. Fatal complications are caused not by immediate burn injury, but by the body's reactive response to a thermal stimulus. It is based on the implementation of the local and then a generalized inflammatory response, mediated by the number of proinflammatory cytokines. Delay in the provision of intensive care in the stage of burn shock, delay in surgical repair of the skin, failure to identify and to neutralize microbial agents with the use of antimicrobial agents without local action also play a significant role in this process.
Burn necrotic scab is a source of infection and intoxication, so it should be removed as soon as possible, before the development of severe endogenous intoxication [3]. Therefore, the concept of early surgical necrectomies of burn wounds with their primary plasticity is rational, as well as the development of means for the prevention and treatment of wound infection, the restoration of anatomical structures and non-surgical correction in the postoperative period [1] [2]. However, the mechanism of the formation of endogenous intoxication in patients with burn injury was not fully established yet. There is no thorough understanding of the pathogenetic changes, that occur in burn injury, which does not allow to form an effective treatment strategy.
It should be noted, that because of presence of endogenous intoxication, conformational changes of the albumin BS molecules occur due to their interaction with toxins [4] [5]. Within the MFS, the excitation of BS was performed at a wavelength of 280 nm, which corresponds to the excitation region of human serum albumin.
Pathologically altered albumin causes changes in the fluorescence spectrum of the BS, which we detect within our research. This method allows to record these changes 24 -48 hours before the onset of pronounced clinical manifestations [6].
It was successfully used for the early diagnosis of sepsis (patent of Ukraine N˚76953) [7] and postpartum purulent-inflammatory diseases (patent of Ukraine N˚33472) [8]. In scientific publications [9] [10], we tested the use of MFS for the diagnosis of endogenous intoxication in patients with burn injury, taking into account similar mechanisms of its formation in sepsis and burn injury, despite various etiological factors.
The aim of the research is to improve the diagnostic and therapeutic approach to the detection and elimination of endogenous intoxication in patients with burn injury.

Data and Methodology
The clinical base of the research was the burn department of Lviv's Communal International Journal of Clinical Medicine

Data Source
In the framework of this research, we investigated and analyzed the main factors, including clinical data, classification of burns, depending on the etiological factor, area and depth of lesion, localization, laboratory examination data (general blood test, general analysis of urine, biochemical blood test, bacterioscopic examination), ultrasonographic examination, MFS.

Research Results
During our research, we analyzed clinical data, results of laboratory, instrumen-   Table 1. Spectral-fluorescence parameters (fluorescence intensity (I F ) and the position of the maximum fluorescence band (λ max )) of blood serum of patient 1.  In Figure 2, there are depicted the results of studies in the dynamics of fluorescence spectra, and in Table 2 (Table 2).
During the continuation of treatment (massive infusion therapy and 100 ml of 20% albumin solution on the 13 th of July), slight changes in the spectral-fluorescence characteristics of BS were recorded. After the cancellation of treatment, the patient's condition gradually stabilized (on the 24 th of July I F = 0.87 r.u.) ( Table 2) and he was discharged from the hospital on the 24 th of July, 2015 in satisfactory condition.
In a slightly different scenario, there was a change in the spectral-fluorescence characteristics of the BS of the next patient with burn injury, with a burn surface area 40%. The results of the study of FS of this patient are depicted in Figure 3, and in Table 3     Further in dynamics on the 15 th of July, 2015 there was an increase in the fluorescence band of the patient's BS (I F = 1.05 r.u., Table 3), which cannot be interpreted as absolute hypoproteinemia, which typically causes a decrease in the fluorescence concentration quenching inherent in transient fluorescence [11].
Thereafter, there was a gradual decrease in the fluorescence intensity of the BS to The results of FS of BS of two more patients with burn injury are depicted on Figure 5 and Figure 6. The corresponding results for the spectral-fluorescence characteristics for their BS are presented in Table 5 and Table 6. They were International Journal of Clinical Medicine      Table 6. Spectral-fluorescence parameters (fluorescence intensity (I F ) and the position of the maximum fluorescence band (λ max )) of blood serum of patient 6. with burn area 32% there was a significant volume of infusion therapy (more than 2 liters daily), so the fluorescence intensity was higher than 1 (curves 5.1 and 5.2). This is consistent with the results of the in vitro study [11]. As the volume of infusion therapy decreased, the fluorescence intensity began to decrease replenish the complete albumin in the patient's body, capable of performing its functions [12].
After the cancellation of the infusion of 10% albumin solution, the fluorescence intensity continued to decrease to I F = 0.78 r.u. (curve 5.4), despite continued antibiotic therapy and antibiotic replacement. Against the background of continued treatment, the following improvement of the patient's condition was noted (curves 5.5 and 5.6), and the fluorescence intensity after completion of the treatment at the time of discharge from the hospital was I F = 0.97 r.u. FS of BS of the next patient is depicted on Figure 6. The area of the burn surface of this patient was 28%. The volume of infusion therapy of this patient did not differ significantly from the corresponding volume of the previous patient, but the fluorescence intensity of his BS was low (curve 6.1 I F = 0.41 r.u., curve 6.2 I F = 0.37 r.u.). His condition was much more severe, than the condition of the previous patient. During further treatment, including effective antibiotic therapy, as well as infusion of 10% albumin solution (6 th , 10 th , 15 th , 18 th of July, 2017), the fluorescence intensity began to increase from 0.46 r.u. (curve 6.3) up to 0.95 r.u. (curve 6.7). After that, the patient was discharged from the hospital in satisfactory condition.
Thus, we successfully used MFS for patients of the main group to diagnose endogenous intoxication and monitor their condition. The behavior of spectral-fluorescent characteristics of the BS of patients of different severity was under study. Standard treatment regimens were improved. It is noteworthy, that infusions of albumin solution were provided in case the patients felt worse. This ensured a successful treatment process and proper control. We took into account the treatment process under the control of MFS and formed a comparison group of 10 patients, who were treated without supervision within the MFS. But in case of the negative clinical dynamics of the patient's condition, we adjusted the treatment process by including infusions of albumin solution. In all cases, a positive effect was observed due to the changes of treatment tactics. All the patients, 60% of whom were in serious condition, were discharged from the hospital in satisfactory condition after the successful completion of their treatment.
The comparison group consisted of patients with burn injuries of first-and second-degree burns (type A and B), who was hospitalized at the stage of burn shock in the burn department of Lviv's Communal Clinical Hospital No 8 in 2019-2020. The area of burnt surfaces of patients in the comparison group ranged from 10% to 35%. 60% of the patients in the comparison group were admitted to the hospital in serious condition, and 40% of the patients were in moderate condition. Now we can focus on a few clinical cases. A 38-year-old patient's occupational injury was treated in the hospital from the 30 th of August to the 13 th of November, 2019. At the time of admission, the patient's condition was serious. The main diagnosis was second-degree (type A and B) flame burn of 35% of the head, neck, back and both upper limbs, second-degree burn shock. The patient had a fever and endogenous intoxication. The general blood test revealed leukocytosis with the increased number of rod granulocytes and the in-International Journal of Clinical Medicine ries. The experience and skills, gained by using this method, have contributed greatly to the improvement of treatment tactics for severe patients with burn injuries, whose treatment was carried out without the use of MFS. At the same time, further thorough research is very important to improve the diagnosis and treatment tactics, especially during severe purulent-inflammatory diseases, like sepsis.

Conclusions
Using the method of fluorescence spectroscopy, at the first time, spectral-fluorescence characteristics of blood serum were obtained for the patients with