++
KEY CONCEPTS
The utility of a single serum creatinine measurement as an indicator of glomerular filtration rate (GFR) is limited in critical illness: The rate of creatinine production, and its volume of distribution, may be abnormal in the critically ill patient, and the serum creatinine concentration often does not accurately reflect GFR in the physiological disequilibrium of acute kidney injury (AKI).
Creatinine clearance measurement is the most accurate method available for clinically assessing overall kidney function.
The accumulation of morphine and meperidine metabolites has been reported to prolong respiratory depression in patients with kidney failure.
Succinylcholine can be safely used in patients with kidney failure in the absence of hyperkalemia at the time of induction.
Extracellular fluid overload from sodium retention, in association with increased cardiac demand imposed by anemia and hypertension, makes patients with end-stage kidney disease particularly prone to congestive heart failure and pulmonary edema.
Delayed gastric emptying secondary to kidney disease–associated autonomic neuropathy may predispose patients to perioperative aspiration.
Controlled ventilation should be considered for patients with kidney failure under general anesthesia. Inadequate spontaneous or assisted ventilation with progressive hypercarbia under anesthesia can result in respiratory acidosis that may exacerbate preexisting acidemia, lead to potentially severe circulatory depression, and dangerously increase serum potassium concentration.
Correct anesthetic management of patients with renal insufficiency is as critical as management of those with frank kidney failure, especially during procedures associated with a relatively high incidence of postoperative kidney failure, such as cardiac and aortic reconstructive surgery.
Intravascular volume depletion, sepsis, obstructive jaundice, crush injuries, and renal toxins, such as radiocontrast agents, certain antibiotics, angiotensin-converting enzyme inhibitors, and nonsteroidal antiinflammatory drugs, are major risk factors for acute deterioration in kidney function.
Kidney protection with adequate hydration and maintenance of renal blood flow is especially important for patients at high risk for AKI and kidney failure undergoing cardiac, major aortic reconstructive, and other surgical procedures associated with significant physiological trespass. The use of mannitol, low-dose dopamine infusion, loop diuretics, or fenoldopam for kidney protection is controversial and without proof of efficacy.
++
Acute kidney injury (AKI) is a common problem, with an incidence of up to 5% in all hospitalized patients and up to 8% in critical illness. Postoperative AKI may occur in 1% or more of general surgery patients, and up to 30% of patients undergoing cardiothoracic and vascular procedures. Perioperative AKI is a markedly underappreciated problem that greatly increases perioperative morbidity, mortality, and costs. It is a systemic disorder that can include fluid and electrolyte derangements, respiratory failure, major cardiovascular events, weakened immunocompetence leading to infection and sepsis, altered mental status, hepatic dysfunction, and gastrointestinal hemorrhage. It is also a major cause of chronic kidney disease. Preoperative risk factors for perioperative AKI include preexisting kidney disease, hypertension, diabetes mellitus, liver disease, sepsis, trauma, hypovolemia, multiple myeloma, and age greater than 55 years. The risk of perioperative AKI is also increased by exposure to nephrotoxic agents such as nonsteroidal antiinflammatory ...