Renal Function and Failure Overview

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Questions and Answers

What defines anuria?

Complete absence of urine production (correct)

Increased urine production

Production of less than 300 ml of urine per day

Excretion of normal urine volume

Which of the following is a prerenal cause of acute renal failure?

Hypovolaemia (correct)

Angiotensin-converting enzyme inhibitors

Contrast media

Myoglobinuria

Which conditions can lead to oliguria?

Excreting more than 300 ml of urine per day

Dehydration and excessive sweating (correct)

Sepsis from any cause

Chronic renal failure

What role does hypoxia play in renal function?

It impairs renal function Signup and view all the answers

Which of the following substances is known to be nephrotoxic?

Aminoglycosides Signup and view all the answers

What is a common obstructive cause of acute renal failure?

Calculi Signup and view all the answers

What condition is associated with myoglobinuria?

Crush syndrome Signup and view all the answers

What is a likely consequence of incompatible blood transfusion?

Renal failure with myoglobinuria Signup and view all the answers

Which of the following is a renal cause of acute renal failure?

Drug toxicity Signup and view all the answers

What is a likely cause of unilateral renal colic?

Non-function of the contralateral kidney Signup and view all the answers

Which condition can lead to obstruction of the ureters?

Retroperitoneal fibrosis Signup and view all the answers

What can cause crystalluria in patients receiving chemotherapy?

Inadequate allopurinol treatment Signup and view all the answers

Which sign may indicate a prerenal cause of reduced urine output?

Increased specific gravity of urine Signup and view all the answers

What imaging technique can show ureteric dilatation in suspected obstruction?

Ultrasonography Signup and view all the answers

Which characteristic is NOT associated with progressing to chronic renal failure?

Increased kidney size on imaging Signup and view all the answers

What is the first phase in the progression of renal failure caused by acute tubular necrosis?

Oliguria phase Signup and view all the answers

What should be assessed to rule out prerenal causes of reduced urine output?

Fluid balance chart Signup and view all the answers

Which drug class is associated with the cause of crystalluria?

Sulphonamide medications Signup and view all the answers

Which factor is essential to check when a voided urine sample cannot be obtained?

Catheterization of the bladder Signup and view all the answers

What is the primary purpose of a percutaneous nephrostomy?

To drain urine and pus from an obstructed kidney Signup and view all the answers

What imaging technique is used to guide the insertion of a J-stent?

Retrograde ureterogram under fluoroscopic control Signup and view all the answers

Which step involves the use of a guide wire during the J-stent insertion procedure?

Rail-roading the stent Signup and view all the answers

What is a potential complication of having a J-stent in place?

Infection and encrustation Signup and view all the answers

Why is open surgery for nephrostomy considered rare?

Minimally invasive methods are available Signup and view all the answers

What is the purpose of curling the ends of the J-stent to form a J-shape?

To secure the device against migration Signup and view all the answers

What is the initial management aimed at restoring in patients with hypovolaemia or sepsis?

Circulating volume deficit Signup and view all the answers

What medication may improve cardiac efficiency in patients with hypovolaemia?

Dopamine Signup and view all the answers

When urine production is not restored, what medication can be given, albeit with nephrotoxicity concerns?

Furosemide Signup and view all the answers

What is the aim for central venous pressure in management?

7–9 cmH2O Signup and view all the answers

What characterizes the oliguric phase of renal failure?

Hyperkalaemic acidosis Signup and view all the answers

Why is careful monitoring and management of fluid and electrolyte requirements necessary during the diuretic phase?

Heavy loss of sodium and potassium Signup and view all the answers

What treatment may become necessary if rising serum potassium levels are detected?

Hemodialysis Signup and view all the answers

What is a potential adverse effect of using mannitol in patients?

Circulatory overload Signup and view all the answers

What phase of acute kidney injury may last up to 6 weeks?

Diuretic phase Signup and view all the answers

What should be administered with extreme care to avoid circulatory overload when oral or enteral feeding is not possible?

Parenteral nutrition Signup and view all the answers

What is a key aspect of general nursing care for seriously ill or comatose patients?

Meticulous recording of fluid balance Signup and view all the answers

Which therapy is specifically indicated for patients experiencing significant uraemic symptoms?

Renal replacement therapy Signup and view all the answers

What is a potential disadvantage of acute peritoneal dialysis?

It can introduce infection into the peritoneum Signup and view all the answers

What technique is used to keep lines patent between sessions of haemodialysis?

Heparin solution Signup and view all the answers

What treatment is recommended for obstructive renal failure when surgery is too risky?

External drainage using a nephrostomy Signup and view all the answers

How does haemofiltration compare to haemodialysis?

It causes less haemodynamic upset Signup and view all the answers

What method is used for fluid drainage in acute peritoneal dialysis?

Running sterile dialysis fluid into the peritoneal cavity Signup and view all the answers

Which of the following patients would require non-nephrotoxic antibiotics?

Patients at risk of generalized infection Signup and view all the answers

What is a common nursing measure to prevent pressure sores in immobile patients?

Regular turning and care of pressure areas Signup and view all the answers

What complication might occur with uncontrolled hyperkalaemia?

Altered states of consciousness Signup and view all the answers

Study Notes

Anuria and Oliguria

Anuria refers to the complete absence of urine production.
Oliguria occurs when urine output is less than 300 ml per day.

Renal Blood Flow

Kidney function and urine production hinge on oxygenated blood perfusion.
Reduced renal blood flow or hypoxia can impair kidney function.

Types of Renal Failure

Renal failure is classified into three categories:
- Prerenal: Caused by factors affecting blood flow to the kidneys.
- Renal: Caused by damage to the kidney itself.
- Postrenal: Resulting from obstruction in the urinary tract.

Prerenal Causes

Hypovolemia: Inadequate fluid intake or excessive water loss from dehydration, vomiting, diarrhea, burns, or sweating.
Blood loss: Acute loss often due to trauma or surgery.
Sepsis: Gram-negative septicemia can lead to shock and renal impairment, particularly in immunocompromised individuals.
Cardiogenic shock: Can result from myocardial infarction-related dysarhythmia or pulmonary embolus, reducing cardiac output.
Anesthesia: Hypotension can occur following epidural or spinal anesthesia.
Hypoxia: Prolonged hypoxia from various causes may occasionally lead to renal impairment.

Renal Causes

Nephrotoxic Drugs: Aminoglycosides, cephalosporins, diuretics, NSAIDs, and ACE inhibitors may lead to renal failure.
Poisons: Certain toxins can harm renal function.
Contrast Media: Can induce renal failure in dehydrated patients with pre-existing issues.
Eclampsia: Early pre-eclampsia recognition prevents nephrotoxic effects.
Myoglobinuria: Associated with crush syndrome post-trauma.
Incompatible Blood Transfusion: May result in renal failure.
Disseminated Intravascular Coagulation (DIC): Often follows major sepsis or blood transfusions.

Postrenal Causes

Calculi: Common cause of acute obstruction leading to anuria; may accompany renal colic.
Pelvic Malignancy: Tumors from bladder, prostate, cervix, ovary, or rectum may obstruct ureters.
Surgery: Ureters may be accidentally damaged during pelvic surgeries.
Retroperitoneal Fibrosis: May lead to ureteric obstruction.
Bilharzia: Schistosomiasis can cause ureteric fibrosis and potentially lead to bladder cancer.
Crystalluria: Rarely associated with sulphonamide medications; can occur in chemotherapy patients.

Clinical Assessment

Determine if urine is produced through catheterization if necessary; assess urine specific gravity and appearance for casts or myoglobinuria.
Identify potential prerenal causes through clinical examination and vital signs assessment.
Check for ureteric obstruction via ultrasonography; plain abdominal radiographs for calculi.
Review recent drug administration for potential nephrotoxic agents.
Evaluate for chronic renal failure progression via ultrasound and clinical signs.

Management and Treatment Phases

Acute tubular necrosis progresses through:
- Oliguria Phase: Initial management focuses on restoring circulating volume and correcting tissue hypoxia.
- Diuretic Phase: Typically occurs from the 8th to 10th day; glomerular filtration resumes first.
- Recovery Phase: Not all patients will fully recover; some may require renal replacement therapy.

Supportive Care

Nutritional Support: Administer parenteral nutrition cautiously to avoid overload.
Infection Prevention: Increased infection risk necessitates routine cultures and use of non-nephrotoxic antibiotics.
Fluid Balance Monitoring: Essential for patients; meticulous recording is crucial, especially for seriously ill patients.

Renal Replacement Therapies

Peritoneal Dialysis: Performed if no recent abdominal surgery; involves using the peritoneum for dialysis.
Hemodialysis: Life-saving if performed through a catheter placed in a large vein, but may cause fluid balance fluctuations.
Hemofiltration: Similar to hemodialysis but with less cardiovascular instability.
Obstructive Renal Failure Management: May require drainage via nephrostomy or stent placement if surgical intervention is not viable.

Surgical Interventions

Percutaneous Nephrostomy: Involves catheter insertion for urinary drainage under ultrasound guidance.
J-Stent Insertion: A procedure to drain urine into the bladder using fluoroscopic guidance.
Open Surgery: Rare in the presence of advanced minimally invasive techniques.

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Description

This quiz covers key concepts related to renal function, including definitions of anuria and oliguria, as well as the classifications of renal failure: prerenal, renal, and postrenal. Explore the importance of renal perfusion and the impact of hypoxia on kidney function.