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Chapter 37 ACUTE URINARY RETENTION268
15. Summarize the different neurogenic causes of AUR.
n
Upper motor neuron lesions: Lesions located in the spinal cord above the sacral
micturition center (L2 vertebral level, S2–S4 spinal segments) result in a spastic or
reflex bladder. Common causes are spinal cord trauma, tumor, and multiple sclerosis.
Lesions of the cerebral cortex (e.g., acute stroke, bleed) usually cause chronic loss of
bladder control and incontinence, except in the acute phase, when the lesions typically
produce AUR.
n
Lower motor neuron lesions: Lesions at the micturition center in the cauda equina
interrupt the sacral reflex arc and produce vesical dysfunction. There is loss of sensation of
bladder fullness leading to overstretch, muscle atony, and poor contraction. Large residuals
are common. The most common causes include spinal trauma, tumor, herniated
intervertebral disks, and multiple sclerosis.
n
Bladder afferent and efferent nerve dysfunction: Dysfunction in this pathway disrupts the
micturition reflex arc that is necessary for proper urination, causing AUR. Common causes
include diabetes mellitus, herpes simplex infection, and the postoperative state.
16. Name the most common complications of AUR.
Infection, hemorrhage, and postobstruction diuresis. All three are more common in patients
with chronic urinary retention.
17. What is autonomic dysreflexia/hyperreflexia, and what does it have to do with
AUR?
An abnormality of the autonomic nervous system seen in patients with long-standing
cervical or high thoracic spinal cord lesions (i.e., quadriplegics and high paraplegics). It is
caused primarily by unchecked reflex sympathetic discharge secondary to visceral or
somatic stimuli below the level of the spinal injury. This potentially life-threatening
syndrome includes severe paroxysmal hypertension, diaphoresis, tachycardia or
bradycardia, anxiety, headache, flushing, seizures, and coma. Morbidity has resulted from
cerebrovascular accident, subarachnoid hemorrhage, and respiratory arrest. One of the
most common precipitating stimuli is overdistention of the bladder (AUR) from a plugged
or kinked catheter. Therefore, it is always important to evaluate these types of patients for
potential Foley catheter problems.
18. What is postobstruction diuresis? How is it managed?
The inappropriate excretion of salt and water after relief of urinary obstruction. Patients with
abnormal renal function or chronic urinary retention are most susceptible. A physiologic
diuresis is normal because the kidneys excrete the overload of solute and volume retained
while obstructed. If urine output persists at high levels, significant fluid and electrolyte
abnormalities may develop. Any patient who exhibits a continuous diuresis after clinical
euvolemia is reached requires hospitalization for hemodynamic monitoring and fluid and
electrolyte repletion.
19. Who can I send home? Who needs admission? Can I remove that catheter?
Most patients with AUR caused by an obstruction require Foley catheterization with
continuous drainage. Reliable patients in good health and without signs of serious systemic
infection are candidates for careful outpatient management with a leg bag and timely urologic
follow-up. The use of prophylactic antibiotics in these patients is controversial. Patients with
new neurogenic causes, severe infection, systemic toxicity, or any lesion that may need
surgical intervention require hospital admission. Some younger patients with pharmacologic
urinary retention may have the catheter removed after decompression. The causative
medication should be discontinued, and the patient should be discharged with instructions to
return if symptoms recur. If the catheter is removed, it is prudent to be sure that patients can
void on their own prior to discharge from the ED.
Chapter 37 ACUTE URINARY RETENTION 269
CONTROVERSY
20. I have heard that gradual emptying of the distended bladder best helps to
prevent complications. Is this true?
Traditionally, the medical literature has recommended gradual emptying of the obstructed,
distended bladder to decrease the risk of hematuria, hypotension, and postobstructive
diuresis. The validity of this practice has long been questioned and inadequately studied.
Recently, however, one study reviewed all of the available literature for each of these
complications and compared quick, complete decompression with gradual emptying. Their
review revealed that, although hematuria, transient hypotension, and postobstructive diuresis
occasionally do occur after rapid emptying of the bladder, they are rarely of any clinical
significance and do not require any treatment. The recommendation is that gradual,
incremental bladder decompression is unnecessary.
WEBSITE
Urinary obstruction: www.emedicine.com
BIBLIOGRAPHY
1. Curtis LA, Dolan TS, Cespedes RD: Acute urinary retention and urinary incontinence. Emerg Med Clin North
Am 19:591–619, 2001.
2. Emberton M, Anson K: Acute urinary retention in men: an age old problem. BMJ 319:1004–1005, 1999.
3. Fitzpatrick JM, Kirby RS: Management of acute urinary retention. BJU Int 97:16–22, 2006.
4. Kahler J, Harwood-Nuss AL: Selected urologic problems. In Marx J, Hockenberger R, Walls R, et al, editors:
Rosen’s emergency medicine: concepts and clinical practice, ed 5, St. Louis, 2006, Mosby, pp 1572–1606.
5. Kaplan SA, Wein AJ, Staskin DR, et al: Urinary retention and post-void residual urine in men: separating truth
from tradition. J Urol 180:47–54, 2008.
6. Krassioukov A, Warburton DE, Teasell R, et al: A systematic review of the management of autonomic
dysreflexia after spinal cord injury. Arch Phys Med Rehabil 90:682–695, 2009.
7. Nyman MA, Schwenk NM, Silverstein MD: Management of urinary retention: rapid vs. gradual decompression
and risk of complications. Mayo Clin Proc 72:951–956, 1997.
8. Rosenstein D, McAninch JW: Urologic emergencies. Med Clin North Am 88:495–518, 2004.
9. Selius BA, Subedi R: Urinary retention in adults: diagnosis and initial management. Am Fam Physician
77:643–650, 2008.
10. Wolf SJ: Urinary incontinence and retention. In Wolfson A, Linden C, Luten RC, et al, editors: Harwood-Nuss’
Clinical practice of emergency medicine, ed 4, Philadelphia, 2005, Lippincott-Raven, pp 443–448.
270
URINARY TRACT INFECTION: CYSTITIS,
PYELONEPHRITIS, AND PROSTATITIS
CHAPTER 38
Sara M. Krzyzaniak, MD
1. Define the terms relevant to the spectrum of urinary tract infection (UTI).
n
Bacteriuria: The presence of bacteria anywhere in the urinary tract. Significant
bacteriuria is defined as .10
5
colony-forming units (CFU) per mL of urine.
n
Cystitis: Significant bacteriuria with bladder mucosal invasion, characterized by
dysuria, urgency, frequency, and sometimes suprapubic discomfort. This term is
often used interchangeably with UTI in clinical practice.
n
Pyelonephritis: Infection of the renal parenchyma and collecting system,
characterized by flank pain, fever, and significant bacteriuria
n
Urethritis or acute urethral syndrome: The clinical syndrome of dysuria, frequency,
and urgency in the absence of significant bacteriuria
n
Prostatitis: A chronic or acute syndrome of prostatic inflammation that presents with
a wide range of symptoms
KEY POINTS: CHARACTERISTICS OF CYSTITIS
1. Dysuria
2. Frequency
3. Urgency
4. Suprapubic discomfort
5. Significant bacteriuria
2. What are the most common causes of UTI?
Escherichia coli is the most common pathogen. Staphylococcus saprophyticus is the
second most common. In immunocompromised or chronically ill patients and in
complicated UTI, Pseudomonas and many members of the Enterobacteriaceae family,
such as Klebsiella, Proteus, and Enterobacter, are commonly involved. Proteus and
Klebsiella predispose to stone formation and grow more frequently in patients with
calculi. Remember these organisms by the mnemonic SEEK PP.
3. What is asymptomatic bacteriuria?
The presence of greater than or equal to 10
5
uropathogens/mL on voided midstream
urine from an asymptomatic patient. When two consecutive specimens contain the same
organism at this concentration, the probability of true bacteriuria rises to 80% to 95%.
4. When should asymptomatic bacteriuria be treated?
n
Pregnancy: associated with 20% to 40% risk of developing symptomatic UTI,
including pyelonephritis. Pyelonephritis during pregnancy is associated with increased
risk of prematurity and low birth weight.
n
Preoperatively: treating urologic surgical patients prior to surgery decreases the risk
of postoperative complications, including bacteremia.
Chapter 38 URINARY TRACT INFECTION: CYSTITIS, PYELONEPHRITIS, AND PROSTATITIS 271
n
There is no evidence to support the treatment of asymptomatic bacteriuria in catheterized
patients or in the elderly; this results in development of resistant pathogens.
5. List the differential diagnoses of dysuria.
n
Infectious: Cystitis, urethritis (gonococcal versus nongonococcal), pyelonephritis,
epididymitis, prostatitis, vulvovaginitis
n
Structural: Calculi, neoplastic lesions
n
Traumatic: Blunt trauma, sexual intercourse or assault, chemical irritants, allergy
6. When should a pelvic examination be done in a female patient with dysuria?
Whenever there is a suspicion that the cause is not a classic UTI. Clinical situations include
external dysuria suggestive of vulvovaginitis, low abdominal pain or bilateral flank pain to rule
out pelvic inflammatory disease, any history of trauma or chemical irritant, and any patient at
high risk for a sexually transmitted disease or sexual abuse. Any patient who fails to respond
to empirical antibiotic therapy for cystitis or who has a negative urinalysis or cultures with a
suspected UTI should have a pelvic examination.
7. What is a routine urinalysis?
There is no standardization of what constitutes a routine urinalysis in the literature. The definition
of significant bacteriuria depends on the relatively costly and slow results of urine culture. Many
screening tests have been evaluated to try to detect UTI earlier and to predict negative cultures,
reducing the number of full urine cultures ordered. These screening tests include the following:
n
Pyuria: The measurement of white blood cells (WBC) in the urine, commonly by
microscopic examination of centrifuged urine sediment and quantification of WBCs per
high-power field (HPF). More than five WBCs/HPF is abnormal.
n
Microscopic evaluation for bacteria: Variable techniques include examination of unstained
and Gram-stained specimens of centrifuged and uncentrifuged urine. Standardization of
this technique is poor, and it is an insensitive test because pathogens in quantities less
than 10
4
CFUs/mL are difficult to find by this technique.
n
Epithelial cells: Estimates of epithelial cells per HPF are used mainly to estimate perineal
contamination of midstream specimens. Although epithelial cells can be derived from
anywhere in the urinary tract, their presence on urinalysis is usually from vaginal epithelial
cells and suggests contamination.
n
Leukocyte esterase: An enzyme found in neutrophils. This test depends on the ability of
any leukocytes present to convert indoxyl carboxylic acid to an indoxyl moiety. When
positive, it is suggestive of but not confirmatory for pyuria.
n
Nitrite: Produced from nitrate by nitrate reductase, an enzyme present in gram-negative
bacteria. To be positive, the bacteria must act on the urine for 6 hours, making a first-voided
morning specimen necessary for optimal testing. It is a specific but not sensitive test for UTI.
8. What is the utility of urinalysis and urine dipsticks in the diagnosis of UTI?
The reported sensitivities, specificities, and likelihood ratios for the previously mentioned
screening tests vary widely in the literature. The pretest probability of cystitis in a population
of patients presenting with any symptoms of dysuria, frequency, or urgency has been
estimated to be approximately 70%. Estimates of screening test sensitivities and specificities
vary so much that the predictive value of a positive test ranges from 75% to 99%, and the
predictive value of a negative test ranges from 40% to 99%. Evidence suggests that urinalysis
and dipstick testing done under practice conditions are not as reliable as when done under
research protocol conditions. As a result, it may be sensible to continue to develop clinical
guidelines involving the empiric treatment of uncomplicated UTI, limiting the use of screening
tests to only patients with low-to-moderate pretest probability estimates.
9. When should I order a urine culture?
A urine culture generally is not required to treat presumptively uncomplicated cystitis in
women. Most clinicians recommend a culture with sensitivities in suspected pyelonephritis
Chapter 38 URINARY TRACT INFECTION: CYSTITIS, PYELONEPHRITIS, AND PROSTATITIS272
because of the potential for serious sequelae if an inappropriate antibiotic is used. All cases of
potentially complicated UTI should also have a urine culture done.
10. What is the difference between complicated and uncomplicated UTI?
A complicated infection is associated with any neurologic, structural, or comorbid condition
that increases the risk for acquiring infection and subsequently reduces the efficacy of
standard treatment regimens. Factors that predispose to a complicated UTI include structural
abnormalities (e.g., calculi, urinary catheters, stents, prostatic infection, and urinary diversion
procedures), metabolic or hormonal abnormalities (e.g., diabetes or pregnancy),
vesicoureteral reflux, immunocompromise, recent urinary tract instrumentation, male gender,
extremes of age (the elderly, young children), unusual pathogens, recent antibiotic use or
failed treatment for UTI, and presence of symptoms for longer than 7 days. It can be argued
that true uncomplicated UTIs occur only in nonpregnant, healthy women with no neurologic or
structural dysfunction, with 80% of UTIs falling into this group.
KEY POINTS: CHARACTERISTICS OF COMPLICATED UTIS
1. Structural or neurological abnormality
2. Immunocompromised host
3. Recent instrumentation
4. Failed treatment
5. Male gender or extremes of age
6. Stone or obstructive pathology
11. How should acute, uncomplicated cystitis be treated?
The causative agents are quite predictable, and treatment should be tailored to the specific
bacterial sensitivities and patterns of resistance identified at each institution. The Infectious
Diseases Society of America (IDSA) has recommended that a 3-day regimen of trimethoprim-
sulfamethoxazole (TMP-SMX) be standard therapy for acute uncomplicated cystitis.
Fluoroquinolones, such as ofloxacin, levofloxacin, or ciprofloxacin, for 3 days are considered
to have similar effectiveness as TMP-SMX but are considerably more expensive. Also, in an
effort to postpone emergence of resistance to these drugs, the IDSA does not recommend
them as initial empirical therapy except in regions with known resistance to TMP-SMX of
greater than 10% to 20% among uropathogens. Nitrofurantoin for 7 days or a single dose of
fosfomycin may become more useful as resistance to TMP-SMX increases.
12. What is the ideal length of treatment for uncomplicated, symptomatic cystitis?
Multiple studies have examined ideal length of treatment for uncomplicated, symptomatic
cystitis. Regimens from 1 to 14 days have been investigated. Most studies recommend a
course of antibiotics ranging from 3 to 6 days. This includes elderly women and children.
13. Explain the role of adjunctive treatment with phenazopyridine.
Phenazopyridine (Pyridium) acts as a topical analgesic for the urinary tract and can help
relieve the dysuria associated with symptomatic UTIs. Patients should be advised that it will
turn body secretions/excretions orange, including their urine and tears. Dosing is 200 mg
three times daily after meals for 48 hours.
14. How should acute, uncomplicated pyelonephritis be treated?
The IDSA recommends 14 days of antimicrobial therapy for young, nonpregnant women with
normal urinary tracts. In mild cases, oral fluoroquinolones are considered the first choice for
Chapter 38 URINARY TRACT INFECTION: CYSTITIS, PYELONEPHRITIS, AND PROSTATITIS 273
outpatient treatment of pyelonephritis (e.g., ciprofloxacin 500 mg every 12 hours, levofloxacin
250 mg daily, or ofloxacin 200–300 mg every 12 hours). TMP-SMX for 14 days is an
inexpensive option, but because of increasing antibiotic resistance to this agent in
pyelonephritic strains, the IDSA recommends it be used only if the organism is known to be
susceptible. In patients with a contraindication to fluoroquinolones, alternatives include
cefixime 400 mg daily and cefpodoxime proxetil 200 mg every 12 hours for 14 days. A single-
dose parenteral antibiotic (gentamicin or ceftriaxone) followed by any of the aforementioned
regimens is an acceptable alternative.
KEY POINTS: CHARACTERISTICS OF PYELONEPHRITIS
1. Fever
2. Flank pain
3. Costovertebral angle tenderness
4. Significant bacteriuria
15. Which patients with pyelonephritis should be admitted?
Admission should be strongly considered for patients who are unable to maintain oral
hydration or take oral medications and patients with uncertain social support or concern about
compliance. Other indications include immunocompromise, severe illness with extreme pain,
or marked debility. There is increasing evidence that some subsets of complicated
pyelonephritis can be treated successfully on an outpatient basis. Pregnant patients at less
than 24 weeks’ gestation who are hemodynamically stable have been treated safely as
outpatients if they can be reached easily by phone and are likely to be compliant with
medication and follow-up. Another reasonable option is 24-hour observation for intravenous
hydration and antibiotics with subsequent discharge home on a 10- to 14-day course of
appropriate antibiotics with close follow-up.
16. When should emergency imaging of the urinary tract be obtained in acute
pyelonephritis?
If the patient remains febrile for more than 72 hours on appropriate antibiotic therapy,
computed tomography (CT) or ultrasound should be considered to rule out obstruction and
renal or perinephric abscess. Contrast-enhanced CT scans provide the highest sensitivity for
identifying abscess, obstruction, and acute inflammation.
KEY POINTS: FACTORS THAT MAY REQUIRE ADMISSION
FOR PATIENTS WITH PYELONEPHRITIS
1. Pregnancy
2. Severe illness
3. Inability to maintain oral hydration
4. Uncertain social support/compliance
5. Complicated UTIs
Chapter 38 URINARY TRACT INFECTION: CYSTITIS, PYELONEPHRITIS, AND PROSTATITIS274
KEY POINTS: DURATION OF ANTIBIOTIC TREATMENT
FOR UNCOMPLICATED DISEASE
1. Cystitis: 2-4 days
2. Pyelonephritis: 14 days
3. Prostatitis: At least 30 days
17. How does treatment change for cases of complicated UTI?
n
Duration: A longer course of 7 to 10 days should be prescribed.
n
Pregnancy: Appropriate antibiotic choices include amoxicillin, cephalexin, or nitrofurantoin.
TMP-SMX should not be used in the first two trimesters. Duration is 3 days for
asymptomatic bacteria, otherwise treat as per recommendations for complicated UTIs.
18. What are the signs and symptoms of acute bacterial prostatitis?
The presentation can be dramatic and usually includes frequency, urgency, dysuria, and some
obstructive voiding symptoms in greater than 80% of patients. Other common complaints
include fever (60%), rigors, myalgias, and perineal discomfort (38%). Some patients also
complain of low back pain or rectal pain. The prostate is warm, swollen, and extremely tender.
19. How is acute prostatitis managed?
The pathogen usually can be isolated from voided urine. Prostatic massage and urethral
catheterization should be avoided because they are painful and may precipitate bacteremia.
Severely ill patients should be admitted and treated with intravenous antibiotics. An
aminoglycoside-penicillin derivative combination is often used. Less severely ill patients
respond well to oral fluoroquinolones or TMP-SMX. In one study, more than 95% of cultured
organisms were sensitive to aminoglycosides, cephalosporins, ciprofloxacin, and imipenem as
opposed to 83% sensitivity to TMP-SMX. The duration of therapy should be at least 30 days
to prevent chronic bacterial prostatitis. Supportive measures include hydration, nonsteroidal
anti-inflammatory drugs, sitz baths, and stool softeners. If urinary retention is a problem,
suprapubic aspiration or suprapubic catheter placement is recommended.
20. Name the most common cause of recurrent UTI in men.
Chronic bacterial prostatitis.
21. What are the signs and symptoms of chronic bacterial prostatitis?
This is a syndrome of relapsing subacute illness characterized by mild symptoms of
frequency, urgency, and dysuria. Other symptoms may include back pain, scrotal or perineal
pain, voiding dysfunction, hematospermia, and painful ejaculation. Fever and rigors should not
occur. Symptoms must be present for more than 3 months. Examination is highly variable and
may be normal. A premassage and postmassage of the prostate urinalysis generally should be
done and show repeated postmassage bacteriuria with the same organism.
22. How is chronic bacterial prostatitis treated?
Treatment is difficult with poor cure rates and frequent relapse. Several studies report initial
treatment success with TMP-SMX. However, in the event of failure, prolonged treatment
(2–3 months) with fluoroquinolones is recommended. Recalcitrant infection may require
long-term, low-dose therapy or resection of the prostate. Referral to a urologist generally is
recommended, if possible, before treatment with antibiotics. a
1
-blocking agents show some
promise for relief of symptoms and prevention of recurrence.
Chapter 38 URINARY TRACT INFECTION: CYSTITIS, PYELONEPHRITIS, AND PROSTATITIS 275
ACKNOWLEDGMENT
The editors gratefully acknowledge the contributions of Nicola E.E. Schiebel, MD, and Gayle
Braunholtz, MD, authors of this chapter in the previous edition.
BIBLIOGRAPHY
1. Gupta K, Scholes D, Stamm WE: Increasing prevalence of antimicrobial resistance among uropathogens
causing acute uncomplicated cystitis in women. JAMA 281:736–738, 1999.
2. Lummus WE, Thompson I: Prostatitis. Emerg Med Clin North Am 19:691–707, 2001.
3. Lutters M, Vogt-Ferrier NB: Antibiotic duration for treating uncomplicated, symptomatic lower urinary tract
infections in elderly women. Cochrane Database of Systematic Reviews 2008, Issue 3. Art. No.: CD001535.
DOI: 10.1002/14651858.CD001535.pub2.
4. Nicolle L, Bradley S: Infectious Diseases Society of America guidelines for the diagnosis and treatment of
asymptomatic bacteriuria in adults. Clin Infect Dis 40: 643–654 2005.
5. Patterson TF, Andriole VT: Detection, significance, and therapy of bacteriuria in pregnancy. Infect Dis Clin
North Am 11:593–608, 1997.
6. Sheets C, Lyman JL: Urinalysis. Emerg Med Clin North Am 4:263–280, 1986.
7. Stamm WE: Measurement of pyuria and its relation to bacteriuria. Am J Med 75:53–58, 1983.
8. Stevermer JJ, Easley SK: Treatment of prostatitis. Am Fam Physician 15:3025–3026, 2000.
9. Sultana RV, Zalstein S, Cameron P, et al: Dipstick urinalysis and the accuracy of the clinical diagnosis of
urinary tract infection. J Emerg Med 1:13–19, 2001.
10. Warren JW, Abrutyn E, Hebel JR, et al: Guidelines for antimicrobial treatment of uncomplicated acute bacterial
cystitis and acute pyelonephritis in women. Clin Infect Dis 29: 745–758, 1999
11. Winkens RAG, Leffers P, Trienekens TAM: The validity of urinary examination for urinary tract infections in
daily practice. Fam Pract 12:290–293, 1995.
276
CHRONIC RENAL FAILURE AND DIALYSIS
CHAPTER 39
Allan B. Wolfson, MD
1. Isn’t renal failure just another genitourinary disorder?
No. Chronic kidney disease (CKD) is a complex multisystem disorder. The absence of
renal function has obvious consequences for the regulation of total body fluid and
electrolyte balance, limiting the ability to handle fluid and electrolyte loads. CKD also
results in subtle metabolic abnormalities, such as glucose intolerance and lipid
disturbances. Renal failure is associated with numerous end-organ effects, ranging from
pericarditis to renal osteodystrophy, that compromise comfort and normal function.
2. What are the special concerns in patients with renal failure?
Iatrogenic illness is one important consideration, whether arising from
overadministration of fluids or from drug toxicity. Because the effects of renal failure on
drug metabolism and disposition are often complex, it is always advisable to check
recommended dosage adjustments for patients with CKD before administering or
prescribing medications. Even apparently innocuous drugs, such as antacids and
cathartics, may cause morbidity and mortality if used improperly. Patients with CKD
have complications both from the underlying disease that caused renal failure and from
complications of dialysis therapy. They have a limited capacity to respond to infection,
trauma, or other intercurrent illnesses.
3. How is hemodialysis performed?
In hemodialysis, the patient’s blood is brought into contact with a semipermeable
artificial membrane, on the other side of which is a chemically balanced aqueous dialysis
solution. Metabolic waste and electrolytes flow from the patient’s blood into the
dialysate, and other substances (e.g., calcium) may flow from the dialysate into the
blood, acting to normalize blood chemistries. To achieve adequate total body clearances
over the time available for hemodialysis, a high blood-flow rate is necessary. This
requires the cannulation of large vessels or, for long-term dialysis, the creation of an
artificial vascular access site that can be used repeatedly. Hemodialysis typically is
performed for 3 to 5 hours, three times per week.
4. How is peritoneal dialysis (PD) performed?
The patient’s peritoneal membrane serves as the semipermeable barrier between the
blood (in the peritoneal capillaries) and a balanced dialysate solution. The latter is
introduced into the patient’s peritoneal cavity and allowed to dwell for a period of hours
before being drained and replaced. An osmotic gradient is created by using a dialysate
with high concentrations of glucose that, through osmosis, pulls water from the
intravascular space into the dialysate, acting to correct volume overload. For patients
with CKD on chronic ambulatory peritoneal dialysis (CAPD), about 2 L of dialysate
dwells continuously within the peritoneal cavity. It is exchanged for fresh dialysate in a
sterile fashion by the patient four times a day. In another type of peritoneal dialysis,
termed automated peritoneal dialysis (APD) or continuous cycling peritoneal dialysis
(CCPD), exchanges are performed by an automatic cycling machine. For both types,
special peritoneal access is required in the form of a surgically implanted Teflon catheter
(Tenckhoff catheter), through which dialysate is infused and drained.
Chapter 39 CHRONIC RENAL FAILURE AND DIALYSIS 277
5. What is the most common problem relating to the vascular access device in
the ED?
Thrombosis should be suspected when patients report loss of a pulse or thrill in the vascular
device. More often, they present to the ED when there has been a problem establishing
adequate flow during a hemodialysis session. The only intervention necessary is a prompt call
to a vascular surgeon. An angiogram defines the nature and extent of the obstruction and
delineates anatomic lesions, allowing the surgeon to revise or replace the access.
6. How do I diagnose and treat a vascular access infection?
Infection is obvious when the patient presents with signs of inflammation localized to the
access site. The difficulty is that many patients present only with fever and without specific
localizing signs. A useful rule of thumb in such instances is to assume that an endovascular
access infection is present and to treat accordingly. After blood cultures are obtained, patients
typically can be sent home after one dose of an appropriate antibiotic, provided that they look
well and are reliable for follow-up. A single dose of vancomycin, 1 g intravenously, is the
treatment of choice because most infections are staphylococcal and the drug’s duration of
action is 5 to 7 days in CKD. Vancomycin is not hemodialyzable, and its major toxicity is to
the kidneys. If gram-negative infection is suspected, a third- or fourth-generation
cephalosporin, aztreonam, or an aminoglycoside should be added to the regimen. Careful
follow-up should be arranged with the patient’s dialysis nurse or physician.
7. When can the vascular access device be used for giving intravenous (IV)
infusions or for drawing blood?
Hemodialysis patients are instructed never to allow their blood pressure to be taken in the arm
with the vascular access site or to allow their blood to be drawn or IV fluids to be infused
through the vascular access. This is to protect the access device, which is truly the patient’s
lifeline. Occasionally, however, there is no reasonable alternative but to use the access device
for blood drawing or IV lines. In these situations, cautious use of the vascular access device is
permissible, provided that certain guidelines are followed.
When using the access site to draw blood, a tourniquet should not be used. At most, one
finger can be used to tourniquet the vein lightly. The presence of a thrill should be
documented before and after the procedure. The area should be cleaned thoroughly with a
topical antiseptic, and sterile technique should be observed. Care should be taken not to
puncture the back wall of the vessel, and after the puncture, firm but nonocclusive pressure
should be applied to the site for several minutes to ensure that extravasation does not occur.
Obvious aneurysms should not be punctured.
When using the vascular access for an IV line, similar precautions should be observed.
Because the vessel is under arterial pressure, a pressure bag or, preferably, an automated
infusion device is an absolute requirement (certainly when infusing medications).
8. How is PD-associated peritonitis diagnosed?
Peritonitis associated with PD occurs about once per year in even the most fastidious and
well-motivated patients. In contrast to other types of peritonitis, it tends to be mild clinically,
and most patients can be managed without hospital admission. PD-associated peritonitis is
caused most commonly by gram-positive organisms, which are thought to be introduced
KEY POINTS: PROBLEMS WITH VASCULAR ACCESS DEVICES
1. Thrombosis
2. Hemorrhage
3. Infection (often inapparent)