Acute Kidney Injury in the Intensive Care Unit

Abstract

Acute kidney injury (AKI) is defined as an abrupt decrease in glomerular filtration rate (GFR). Incidence varies from 20% to as high as 70% in critically ill patients. Classically, AKI has been divided into three broad pathophysiologic categories: prerenal AKI, intrinsic AKI, and postrenal (obstructive) AKI. The clinical manifestations of AKI vary among a wide range of symptoms and metabolic abnormalities. A sudden decrease in GFR will result in rising concentrations of solutes in the blood, which are normally excreted by the kidneys. Recently, new urinary and serum biomarkers have gained a place in the diagnosis, classification, and prognosis prediction of AKI. The best treatment for AKI is prevention. Patients with prerenal azotemia should have intravascular volume deficits corrected and cardiac function optimized. Obstructive (postrenal) kidney disease is treated by mechanical relief of the block. The primary management of acute interstitial nephritis is discontinuation of the inciting agent. Renal replacement therapy (RRT) has emerged as a supportive mechanism rather than just as a lifesaving measure. Continuous techniques are preferable in treating critically ill patients, although every modality has its benefits, indications, and contraindications.

Determining the Incidence of Acute Kidney Injury Using the RIFLE Criteria in the Medical Intensive Care Unit in a Tertiary Care Hospital Setting in Pakistan

“…Whereas the incidence of AKI in the general population is considered to be low, its incidence in hospitalized patients is much greater, and in ICU patients, it can be as much as 50% [21-24]. With the introduction of classification systems, such as AKIN and RIFLE, the incidence of AKI has increased, partly because of increased identification, so much so that up to 70% of ICU patients have been reported to have some sort of AKI or renal dysfunction [25]. AKI has a mortality rate of 20%-90% [26].…”

Outcome of Acute Kidney Injury (AKI) Patients in the Intensive Care Unit of Enam Medical College & Hospital During the Period of July 2018 to May 2019

“…AKI usually presents with a wide range of signs and symptoms 9 which may include abnormal laboratory findings without clinical symptoms, fluid overload, hyperkalemia, hyponatremia, hypocalcemia, hypercalcemia, hyperphosphatemia, hypomagnesemia, hyperuricemia, metabolic acidosis, anemia, bleeding diatheses, increased risk of infection, multi-organ dysfunction including cardiovascular dysfunction, respiratory failure, gastrointestinal complications, and neurological disorder.…”

“…Sudden decrease in glomerular filtration rate (GFR) represents with an increase in serum urea and creatinine (usually 1−2 mg/dL/day), Urine output less than 400−500 mL/day or less than 20 mL/hour in a high-risk patient in the absence of volume depletion indicates the presence of AKI. 9 The common causes of AKI are ischemia, hypoxia and nephrotoxicity which cause vasoconstriction, endothelial damage, activation of inflammatory process, low renal blood flow and decreased GFR. However, a prolonged decrease in renal perfusion causes irreversible ischemic damage leading to ischemic AKI.…”

Acute Kidney Injury at ICU: Review Article

“…Upper tract obstruction refers to obstructions that occur above the bladder. Upper tract blockage requires bilateral occlusion or unilateral obstruction in the presence of a single working kidney (10) . Cases with obstructive disease may exhibit anuria, normal or increased urine volume, or fluctuating urinary outflow obstruction with durations of anuria intermixed with flow of urine when renal pelvis pressure increases and overwhelms the obstruction.…”