From the Guidelines
Seek immediate medical attention if you have not produced urine for 16 hours, as this is a medical emergency that requires prompt evaluation. This condition, called anuria, indicates severe kidney dysfunction or a complete blockage in the urinary tract. According to the most recent and highest quality study 1, anuria can be a sign of acute kidney injury (AKI) or chronic kidney disease (CKD), both of which require immediate medical attention to prevent further complications.
Causes of Anuria
The causes of anuria can be categorized into three main groups: prerenal, renal, and postrenal. Prerenal causes include impaired blood flow to the kidneys, such as hypotension, hypovolemia, or decreased cardiac output. Renal causes include diseases that damage the renal parenchyma, such as vasculitis, acute tubular necrosis, or glomerulonephritis. Postrenal causes include obstruction of the urinary tract, such as ureteral or bladder obstruction.
Evaluation and Treatment
At the hospital, healthcare providers will likely insert a urinary catheter to check for obstruction, perform blood tests to assess kidney function, and conduct imaging studies like ultrasound to identify the cause. Treatment depends on the underlying cause but may include intravenous fluids, removal of obstructions, dialysis in severe cases, or medications to improve kidney function. As stated in the study 1, earlier detection of AKI by laboratory or clinical parameters allows earlier intervention and probably increased chance of prevention or amelioration.
Importance of Prompt Evaluation
Prolonged anuria can lead to dangerous electrolyte imbalances, fluid overload, and buildup of toxins in the bloodstream. The kidneys normally filter waste products and maintain fluid balance, so complete cessation of urine output indicates a serious disruption to this vital function that requires professional medical intervention. As noted in the study 1, patients with AKD may have signs directly referable to the kidney or have associated nonkidney manifestations, and evaluation and management of AKD depends on clinical context, local resources, and local health care systems.
Key Takeaways
- Anuria is a medical emergency that requires prompt evaluation and treatment.
- The causes of anuria can be categorized into prerenal, renal, and postrenal causes.
- Evaluation and treatment of anuria depend on the underlying cause and may include intravenous fluids, removal of obstructions, dialysis, or medications to improve kidney function.
- Prompt evaluation and treatment are crucial to prevent further complications and improve patient outcomes.
From the FDA Drug Label
In patients at high risk for radiocontrast nephropathy, furosemide can lead to a higher incidence of deterioration in renal function after receiving radiocontrast compared to high-risk patients who received only intravenous hydration prior to receiving radiocontrast. Reversible elevations of BUN may occur and are associated with dehydration, which should be avoided, particularly in patients with renal insufficiency Furosemide may decrease arterial responsiveness to norepinephrine Furosemide can increase the risk of cephalosporin-induced nephrotoxicity even in the setting of minor or transient renal impairment There are case reports of patients who developed increased BUN, serum creatinine and serum potassium levels, and weight gain when furosemide was used in conjunction with NSAIDs.
The cause of anuria (absence of urine output) for 16 hours, indicating potential impaired renal function, may be due to several factors, including:
- Dehydration: associated with reversible elevations of BUN 2
- Nephrotoxicity: increased risk with concomitant use of certain drugs, such as cephalosporins, cyclosporine, or NSAIDs 2, 2
- Deterioration in renal function: particularly in patients at high risk for radiocontrast nephropathy 2
- Electrolyte imbalance: hypokalemia, hypomagnesemia, or hypocalcemia, which can occur with furosemide therapy 2, 2
- Concomitant use of other medications: such as angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, or lithium, which can lead to severe hypotension and deterioration in renal function 2
From the Research
Causes of Anuria
The absence of urine output for 16 hours, also known as anuria, can be caused by various factors related to impaired renal function. Some of the possible causes include:
- Decrease in glomerular filtration rate due to decreased renal blood flow or renal perfusion pressure 3
- Neurohormonal factors and functional changes that influence diuresis and natriuresis in critically ill patients 3
- Structural, medication/toxicologic, neurologic, or infectious etiologies that can cause acute urinary retention 4
- Acute kidney injury (AKI) due to decreased renal perfusion, drug-induced, contrast-associated, postoperative, or sepsis-associated AKI 5
Diagnosis and Management
Diagnosis of the underlying cause of anuria is crucial for appropriate management. This can be done through:
- Medical record review, thorough history and physical examination, urinary and blood tests, renal imaging, and renal biopsy 5
- Intensive monitoring of urine output to detect acute kidney injury and improve outcomes 6
- Loop diuretic challenge to predict the need for dialysis in patients with stage 3 acute kidney injury 7
Possible Etiologies
Possible etiologies of anuria include: