Akutno bubrežno oštećenje (ABO) je bitan klinički čimbenik, poglavito u bolesnika koji se liječe u jedinici intenzivnog liječenja. Prema mnogim studijama, predstavlja ključni čimbenik rizika smrtnosti, neovisno o demografskim karakteristikama ispitanika i težini bolesti. Pojavnost i smrtnost vezano uz taj klinički entitet variraju pa se zbog toga javila potreba za primjenjivim klasifikacijskim sustavom koji bi pomoga u postavljanju dijagnoze, standardizaciji definiranja jačine bubrežnog oštećenja te prognozi ishoda. Tako je 2004. godine utvrđena RIFLE (Risk-Injury-Failure-Loss-End-stage renal disease, engl.), a 2007. AKIN (Acute Kidney Injury Network, engl.) podjela ABO. U kliničkim jedinicama za liječenje kroničnog zatajivanja srca, hipervolemija (koja se u literaturi obično naziva dobivanje na težini) se uzima kao biljeg srčane dekompenzacije. Početak liječenja kontinuiranim metodama nadomještanja bubrežne funkcije poboljšava preživljenje u tih bolesnika na način da se prevenira akumulacija tekućine u organizmu te posljedična hipervolemija. Prevencija, a ne samo ispravak hipervolemije, bi trebala biti indikacija za početak liječenja vantjelesnim kontinuiranim metodama za uklanjanje viška tekućine,
neovisno o potrebi za klirensom određenih molekula. Oligurija je definirana proizvodnjom urina manjom od 0,3 ml/kg/sat u najmanje 24 sata. Svaka odgoda liječenja oligurije može dovesti do ABO te je stoga njeno rano prepoznavanje izuzetno važno.
Bolesnici u jedinicama intenzivnog liječenja s oliguričnim ABO su izloženi povećanom riziku neravnoteže tjelesne tekućine zbog sustavne upale, smanjenog onkotskog tlaka plazme te povećane kapilarne permeabilnosti. Osim toga, posebice su izloženi riziku za razvoj hipervolemije te je zbog toga restriktritvana strategija unosa tekućine u tih bolesnika prijeko potrebita kad god je to moguće.Acute kidney injury (aki) is an important clinical issue, especially in the setting of critical care. it has been shown in multiple studies to be a key independent risk factor for mortality, even after adjustment for demographics and severity of illness. there is wide agreement that a generally applicable classification system is required for aki which helps to standardize estimation of severity of renal disfunction and to predict outcome associated with this condition. that’s how rifLe (risk-injury-failure-Loss-end-stage renal disease), and akiN (acute kidney injury Network) classifications for aki were found in 2004 and 2007, espectively. in the clinical setting of heart failure, a positive fluid balance (often expressed in the literature as weight gain) is used by disease management programs as a marker of
heart failure decompensation. oliguria is defined as urine output less than 0,3 ml/kg/h for at least 24 h. since any delay in treatment can lead to a dangerous progression of the aki, early recognition of oliguria appears to be crucial. critically ill patients with oliguric aki
are at increased risk for fluid imbalance due to widespread systemic inflammation, reduced plasma oncotic pressure and increased capillary
leak. these patients are particulary at risk of fluid overload and therefore restrictive strategy of fluid administration should be used. objective, rapid and accurate volume assessment is important in undiagnosed patients presenting with critical illness, as errors may
result in interventions with fatal outcomes. the historical tools such as physical exam, and chest radiography suffer from significantlimitations. as gold standard, radioisotopic measurement of volume is impractical in the acute care enviroment. Newer technologies
offer the promise of both rapid and accurate bedside estimation of volume status with the potential to improve clinical outcomes. Blood assessment with bioimpendance vector analysis, and bedside ultrasound seem to be promising technologies for this need
