Acute kidney injury in the intensive care unit

Abstract

Background. The paper analyzes the frequency of acute kidney injury (AKI) in critically ill patients. Materials and methods. In 2014–2018, a total of 317 patients with the signs of AKI were admitted to the anesthesiology and intensive care unit of Danylo Halytskyi Lviv National Medical University (clinical bases: Lviv Regional Clinical Hospital and Lviv Municipal Emergency Hospital). AKI in 121 patients was caused by sepsis, in 56 cases, it was accompanied by acute destructive pancreatitis, in 84 patients, it occurred after cardiosurgical interventions, and in 56 persons, AKI was caused by nephrotoxic poisons. The technology of renal replacement therapy (RRT), namely low flow continuous veno-venous hemodiafiltration (multiFiltrate device, multiFiltrateKit1 acoustic system by Fresenius) was applied in 64 patients (2016–2018). In 253 individuals, we used intermittent hemodialysis. The dose of the latter was calculated by Kt/V formula. The diagnosis of AKI was made by the Acute injury criteriа (KDIGO) developed and published by the team of researchers in 2012. These criteria included the level of blood creatinine and the urine flow rate. Nephron involvement was evaluated using furosemide stress test: the drug was injected at a dose of 1–1.5 mg/kg. The increase of diuresis above 200 ml indicated the presence of blood flow in the region of proximal convoluted tubule. The opposite case served as a predictor of ARI progression and one of the indications for RRT application. Results. Infusion therapy remains one of the main instruments in terms of influence on homeostasis of patients. It eliminates volemic, metabolic, electrolyte and other disturbances of homeostasis in critically ill patients. Additionally, the excessive intravascular volume of iatrogenic origin causes the complications and the increase of surgical lethality. In our opinion, the inadequate infusion therapy is caused, on the one hand, by the absence of ideal medication and, on the other, by the lack of proper control of physiological and biochemical parameters which are influenced by infusion media and difficulty of their comprehensive evaluation. The volume of infusion therapy was selected for each patient by the indirect evaluation of the cardiac output (esCCO technology by Nihon Kohden). Nutritional therapy is known as another important intensive care technique applied during the RRT. The procedure of RRT as well as other surgical interventions is accompanied by catabolism activation. Its effect is caused by both diffusion mass transfer and the loss of nutrients with effluent, and by the activation of complement and kinin system. The experts of ASPEN (2009) and ESPEN (2016) think that the patients with AKI can be administered standard medications for nutritional therapy according to the recommendations on the protein and calorie requirement for the critically ill patients. However, in case of the development of certain metabolic and electrolyte disorders, as well as continuous RRT, it is necessary to consider the application of special mixtures for the parenteral and enteral nutrition of patients with AKI. Conclusions. We have not found any significant difference in the decrease of lethality depending on RRT technology. However, it is worth taking into account that continuous veno-venous hemodiafiltration has less negative influence on hemodynamics (this is particularly important for critically ill patients). Moreover, this technology is much more maneuvering (“the device is delivered to the patient” and not otherwise). This technology of RRT shows good results in the correction of water balance in patients with AKI and allows performing nutritional therapy in this category of patients to the full extent.