STUDY - Technical - New Dacian's Medicine
Oliguria
(Classical / Allopathic Medicine)
A
cardinal sign of renal and urinary tract disorders,
oliguria is clinically defined as urine output of fewer
than 400 ml per 24 hours. Typically, this sign occurs
abruptly and may herald serious - possibly
life-threatening - hemodynamic instability. Its causes can
be classified as prerenal (decreased renal blood flow),
intrarenal (intrinsic renal damage), or postrenal (urinary
tract obstruction); the pathophysiology differs for each
classification. (See Causes of oliguria.)
HISTORY:
Ask the patient about his usual daily voiding pattern, including frequency and amount. Ask when he first noticed changes in this pattern or in the color, odor, or consistency of his urine. Ask him if he experiences pain or burning during urination.
Note the patient's normal daily fluid intake.
Ask the patient if has had recent episodes of diarrhea or vomiting that might cause fluid loss. Explore associated complaints, especially fatigue, loss of appetite, thirst, dyspnea, chest pain, or recent weight gain.
Review the patient's medical history for renal or cardiovascular disorders, recent traumatic injury or surgery associated with significant blood loss, and recent blood transfusions.
Ask the patient if he has been exposed to nephrotoxic agents, such as heavy metals, organic solvents, anesthetics, or radiographic contrast media.
Obtain a drug history, including prescription and over-the-counter drugs, herbal remedies, and recreational drugs. Also, ask the patient about alcohol intake.
Ask the patient about his usual daily voiding pattern, including frequency and amount. Ask when he first noticed changes in this pattern or in the color, odor, or consistency of his urine. Ask him if he experiences pain or burning during urination.
Note the patient's normal daily fluid intake.
Ask the patient if has had recent episodes of diarrhea or vomiting that might cause fluid loss. Explore associated complaints, especially fatigue, loss of appetite, thirst, dyspnea, chest pain, or recent weight gain.
Review the patient's medical history for renal or cardiovascular disorders, recent traumatic injury or surgery associated with significant blood loss, and recent blood transfusions.
Ask the patient if he has been exposed to nephrotoxic agents, such as heavy metals, organic solvents, anesthetics, or radiographic contrast media.
Obtain a drug history, including prescription and over-the-counter drugs, herbal remedies, and recreational drugs. Also, ask the patient about alcohol intake.
Causes
of oliguria
Oliguria associated with a prerenal or postrenal cause is usually reversible with treatment; it may lead to intrarenal damage if untreated. However, oliguria associated with an intrarenal cause is usually more persistent and may be irreversible.
Prerenal causes: Bilateral renal artery occlusion; Bilateral renal vein occlusion; Cirrhosis; Heart failure; Hypovolemia; Sepsis
Intrarenal causes: Acute glomerulonephritis; Acute pyelonephritis; Acute tubular necrosis; Chronic renal failure; Toxemia of pregnancy
Postrenal causes: Benign prostatic hyperplasia; Bladder neoplasm; Calculi; Retroperitoneal fibrosis; Urethral stricture
Oliguria associated with a prerenal or postrenal cause is usually reversible with treatment; it may lead to intrarenal damage if untreated. However, oliguria associated with an intrarenal cause is usually more persistent and may be irreversible.
Prerenal causes: Bilateral renal artery occlusion; Bilateral renal vein occlusion; Cirrhosis; Heart failure; Hypovolemia; Sepsis
Intrarenal causes: Acute glomerulonephritis; Acute pyelonephritis; Acute tubular necrosis; Chronic renal failure; Toxemia of pregnancy
Postrenal causes: Benign prostatic hyperplasia; Bladder neoplasm; Calculi; Retroperitoneal fibrosis; Urethral stricture
PHYSICAL
ASSESSMENT:
Take the patient's vital signs, and weigh him.
Assess the patient's overall appearance for edema.
Palpate both kidneys for tenderness and enlargement, and percuss for costovertebral angle tenderness. Inspect the flank area for edema or erythema.
Auscultate the heart and lungs for abnormal sounds and the flank area for renal artery bruits.
Obtain a urine sample, and check for abnormal color, odor, or sediment. Use reagent strips to test for glucose, protein, and blood. Measure specific gravity.
Take the patient's vital signs, and weigh him.
Assess the patient's overall appearance for edema.
Palpate both kidneys for tenderness and enlargement, and percuss for costovertebral angle tenderness. Inspect the flank area for edema or erythema.
Auscultate the heart and lungs for abnormal sounds and the flank area for renal artery bruits.
Obtain a urine sample, and check for abnormal color, odor, or sediment. Use reagent strips to test for glucose, protein, and blood. Measure specific gravity.
SPECIAL
CONSIDERATIONS:
Oliguria may result from drugs that cause decreased renal perfusion (diuretics), nephrotoxicity (aminoglycosides and chemotherapeutic agents), urine retention (adrenergic and anticholinergic agents), or urinary obstruction associated with precipitation of urinary crystals (sulfonamides and acyclovir).
Oliguria may result from drugs that cause decreased renal perfusion (diuretics), nephrotoxicity (aminoglycosides and chemotherapeutic agents), urine retention (adrenergic and anticholinergic agents), or urinary obstruction associated with precipitation of urinary crystals (sulfonamides and acyclovir).
PEDIATRIC
POINTERS:
In the neonate, oliguria may result from edema or dehydration. Major causes include congenital heart disease, respiratory distress syndrome, sepsis, congenital hydronephrosis, acute tubular necrosis, and renal vein thrombosis.
Common causes of oliguria in children between ages 1 and 5 are acute post-streptococcal glomerulonephritis and hemolytic-uremic syndrome. After age 5, the causes of oliguria are similar to those in adults.
In the neonate, oliguria may result from edema or dehydration. Major causes include congenital heart disease, respiratory distress syndrome, sepsis, congenital hydronephrosis, acute tubular necrosis, and renal vein thrombosis.
Common causes of oliguria in children between ages 1 and 5 are acute post-streptococcal glomerulonephritis and hemolytic-uremic syndrome. After age 5, the causes of oliguria are similar to those in adults.
AGING
ISSUES:
In elderly patients, oliguria may result from the gradual progression of an underlying disorder or from overall poor muscle tone secondary to inactivity, poor fluid intake, or infrequent voiding attempts.
In elderly patients, oliguria may result from the gradual progression of an underlying disorder or from overall poor muscle tone secondary to inactivity, poor fluid intake, or infrequent voiding attempts.
PATIENT
COUNSELING:
Depending on the cause of the oliguria, tell the patient to restrict fluids to between 600 and 1,000 ml more than the patient's urine output for the previous day. Explain to the patient that he needs to follow a diet low in sodium, potassium, and protein.
Depending on the cause of the oliguria, tell the patient to restrict fluids to between 600 and 1,000 ml more than the patient's urine output for the previous day. Explain to the patient that he needs to follow a diet low in sodium, potassium, and protein.
Bibliography:
1. Rapid Assessment, A
Flowchart Guide to Evaluating Signs & Symptoms, Lippincott
Williams & Wilkins, 2004.
2. Professional Guide to
Signs and symptoms, Edition V, Lippincott
Williams & Wilkins, 2007.
3. Guide to common symptoms,
Edition V, McGraw - Hill, 2002.