LAUSR

AKI is one of the most common and severe complications in severely burned patients. However, it’s aetiology, risk factors, clinic course, treatment and prognostic is still not very clear. The aim of the study was to analyse of incidence, clinic course and risk factors of the Acute Renal Injury (AKI) after massive burn injuries. 33 patients (pts); 11 (33,3%) females, 33 (66,7%) males; admitted to the hospital due to severe burn injury (total body surface area TBSA ≥15%) were involved in the study from 01.01.2017 till 30.06.2019. Mean age of the group was 48,3 (±18,8) years. Patients admitted to the hospital later than 72 hours after injury were excluded from the project. Mean time-period from the injury to the admission time was 2,1 (±0,9) hours. Mean injured skin surface was 42,2 (±18,1%) of the TBSA, the 3rd degree of burn was confirmed at 21 (63,6%) pts, respiratory tract was injured at 23 (69,7%) pts. None of the pts presented symptoms of chronic kidney disease before the injury. Basic life parameters, diuresis and chosen biochemical parameters (i.e. renal function) were measured at each patient once daily from admission till 7th day. Additionally the concentration of chosen novel AKI biomarkers (CystatinC, Neutrophil gelatinase-associated lipocalin, Kidney injury molecule-1, Interleukin-6 and 18, Insulin-like growth factor-binding protein 7, Tissue inhibitors of metalloproteinases 1÷4) were also measured in urine and blood sample during each first 3 day of hospitalisation and compared with the standard renal function parameters. Mean time of the 1st measurement was 44,7(±17,7), the 2nd - 70,8 (±19,2) and 3rd - 94,8 (±19,2) hours after injury. AKI criteria were as follows: decrease in glomerular filtration rate (GFR) of less than 60 ml/min at admission, decrease in GFR of more than 75% compared to baseline, decrease in the daily diuresis of less than 500 ml/24 hours. The medium hospitalisation time was 28,1(±21,5) days. During observation time, clinical and biochemical symptoms of AKI were confirmed in 20 pts (60,6%). 8 (24,2% of all, 40,0% with AKI) required renal replacement therapy RRT: 37,5% (3 pts) - intermitted haemodialysis, 25,0% (2 pts) - continuous veno-venous haemodiafiltration and 37,5% (3 pts) – both methods. AKI developed usually in 3rd day of hospitalisation (maximum in 19th) and RRT usually started at the 8th day (maximum at 20th). The overall mortality was 48,5% (16 pts), 70,0% (14 pts) with AKI and 87,5% (7 patients) in RRT group. Death usually occurred at the 19(±15) day after injury. 2 (12,5%) pts died from hemodynamic disorders in first 7 days, in 59 and 120 hour respectively. There were 14 (87,5%) pts in the group of late mortality (more than 7 days after injury), mean time of death was 24,5 (±15) days, in 57,1% connected with severe infection. The major causes of death in all were: cardiac arrest 14 (87,5%), cardiovascular failure 8 (50,0%), burn/septic shock 5 (37,5%), or respiratory failure 2 (12,5%) pts. The confirmed risk factors of AKI and mortality were injury more than 15% of TBSA, 3rd degree of burn injury age >65 years old, hemodynamic instability demanding catecholamine (p<0,05). AKI was also confirmed as an independent risk factor of mortality (p=0,004). The early analysis suggest potentially benefit of using novel biomarkers AKI in the clinic practise with superiority over standard AKI parameters (the final results of collected data analysis are still in progress). AKI is a frequent and important problem in severely burned patients. The occurrence of AKI significantly worsens the prognosis for survival. It is predicted by such factors as injury more than 15% of TBSA, 3rd degree of burn injury, older age and hemodynamic instability. Assessment of renal function, including novel AKI biomarkers, is an important prognostic factor after thermal injury and should be routine evaluated during treatment of burned patient.