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enal failure is a condition in which the kidneys fail
to remove metabolic end products from the blood
and regulate the fluid, electrolyte, and pH balance of the
extracellular fluids. The underlying cause may be renal
disease, systemic disease, or urologic defects of nonrenal
origin. Renal failure can occur as an acute or a chronic
disorder. Acute kidney injury is abrupt in onset and
often is reversible if recognized early and treated appro-
priately. In contrast, chronic kidney disease is the end
result of irreparable damage to the kidneys. It develops
slowly, usually over the course of a number of years and
often requires dialysis therapy or transplantation.
Acute Kidney Injury
Acute kidney injury (AKI), formerly known as acute
renal failure, represents an abrupt decline in kidney func-
tion, resulting in an inability to maintain fluid and elec-
trolyte balance and excrete nitrogenous wastes.
1–7
Acute
kidney injury is a common threat to seriously ill persons,
in whom it is associated with a high rate of adverse out-
comes, with mortality rates ranging between 25% and
80% depending on the cause and clinical status of the
patient.
1
This high mortality rate probably reflects the
facts that AKI is often seen in elderly persons and that
it is frequently superimposed on other life-threatening
conditions, such as trauma, shock, and sepsis.
Acute renal injury is commonly defined as an abrupt
(within 48 hours) reduction in kidney function based
on an increase in serum creatinine level, a reduction in
urine output, and the need for dialysis, or a combination
of these factors. The range of clinical manifestations can
vary from mild to severe, based on the degree of rise in
creatinine levels and decrease in urine output.
Types of Acute Kidney Injury
Acute kidney injury can be caused by several types of
conditions, including a decrease in blood flow without
R
Acute Kidney
Injury and
Chronic Kidney
Disease
26
C h a p t e r
Acute Kidney Injury
Types of Acute Kidney Injury
Prerenal Injury
Postrenal Injury
Intrarenal Injury
Diagnosis and Treatment
Chronic Kidney Disease
Diagnostic Measures
Clinical Stages
Clinical Manifestations
Fluid, Electrolyte, and Acid–Base Disorders
Cardiovascular Complications
Gastrointestinal Disorders
Disorders of Mineral Metabolism
Hematologic Complications
Immunologic Disorders
Neuromuscular Complications
Sexual Dysfunction
Skin Disorders
Treatment
Conservative Medical Management
Dietary Management
Medication Management
Dialysis and Transplantation
Chronic Kidney Disease in Children and Elderly
Persons
Chronic Kidney Disease in Children
Chronic Kidney Disease in Elderly Persons
