Background. Intraoperative hypothermia develops spontaneously due to trauma, surgical intervention and anesthesia as a result of a violation of the conformity of heat production to heat loss and suppression of the compensatory thermoregulatory response. Intensive care for polytrauma should be aimed at the triad of death: hypothermia, acidosis and coagulopathy, the main links in the pathogenesis of polytrauma. Deterioration of microcirculation due to hypovolemia, direct injury, traumatic coagulopathy, intravascular sludge and endothelial damage disrupts tissue perfusion. Tissue hypoxia, in turn, switches the metabolism to glycolysis and leads to the development of lactic acidosis. Development of hypothermia with polytrauma causes cardiac rhythm disturbance, cardiac output decrease, coagulopathy and displacement of the oxyhemoglobin dissociation curve to the left, which aggravates the severity of acidosis, and, as a result, increases the severity of the state and the level of mortality of such patients. Temperature is one of the most important factors determining the coagulation cascade, and since temperature-sensitive plasma esterase reactions, like the functional activity of platelets, are inhibited by hypothermia, it is not surprising that coagulopathy is the final part of triad of death. It should be emphasized that this occurs in conditions of blood loss, i.e. the initial loss of coagulation factors and the additional development of dilutional coagulopathy associated with infusion therapy to correct hypovolemia causing a pooling of coagulation factors initially at a low level. The purpose of the work was to study the effectiveness of the method for correcting intraoperative hypothermia by means of forced-air warming device in patients with polytrauma. Materials and methods. Twenty patients with polytrauma who underwent urgent surgical interventions were examined. They were divided into 2 groups: group I (n = 10) persons who were actively heated by the WarmAir 135 (CSZ) system with the use of blankets for warming in the operating room — the FilteredFlo 248; group II — control group (n = 10), convection warming wasn’t used. The temperature of the core of the body (Tco) was studied: initially, after 30, 60 minutes and at the end of the operation. The following indices were calculated: minimum (Tmin) and maximum (Tmax) temperature, average temperature (Ta), temperature range (Tr = Tmax – Tmin). Results. When analyzing the initial level of core body temperature at the time of admission to the operating room, there were no significant differences between the groups of patients (P = 0.420). In group I, hypothermia with Tco < 36 °С was detected in 20 % of patients, and in group II — in 10 %. In all patients with polytrauma and urgent surgical interventions, there was a clinically significant intraoperative hypothermia. At the stage of 60 minutes of the intraoperative period, Tco was significantly higher in group I (35.38 ± 0.28 °С) compared with group II (34.70 ± 0.39 °С) (p < 0.05). A significantly higher level of mean Tco in group I (35.53 ± 0.66 °С) was revealed in comparison with group II (34.67 ± 1.74 °С) (p < 0.05). The temperature range, which is the difference between the maximum and minimum Tco, was significantly lower in group I of patients (1.36 ± 0.74 °С) versus group II (4.55 ± 1.11 °С) (p < 0.05). When calculating the maximum decrease in body core temperature in group I with convection heating, this indicator was 13.6 °С, compared with 42.1 °С in group II of patients, which indicated the development of clinically significant intraoperative hypothermia in patients with polytrauma without convection heating. It should also be noted that in both study groups, the maximum increase in Tco was equal to zero, since the value of minimal Tco corresponded to Tco at the end of the surgical intervention. Thus, in patients with severe polytrauma who need urgent surgical interventions, clinically significant hypothermia developed in the intraoperative period influencing the links of homeostasis on the basis of the vicious circle of the polytrauma pathogenesis — the triad of death (acidosis, coagulopathy and hypothermia). It should be emphasized that unintentional hypothermia leads to the development of many complications that arise directly during hypothermia, and no less serious during the recovery of normal thermoregulation. Conclusions. Using forced-air warming device in the intensive care does not allow to reach the initial values of Tco, effectively preventing the progression of hypothermia aggravation and ensuring the maintenance of temperature homeostasis in critically ill patients with polytrauma.
perioperative hypothermia; forced-air warming device; polytrauma; anesthesiology; intensive care
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