Catheter related problems due to an indwelling urinary catheter (IUC) have existed as long as urinary catheters have been utilized. This section will review IUC complications: infectious complications such as (symptomatic bacterial infection, cystitis, pyelonephritis, urosepsis, and epididymitis), catheter blockage (due to calculi, biofilms, and encrustations), catheter related malignancy, hematuria, stones, urethral stricture and fistula from urethral injury, traumatic hypospadias, and periurethral urine leakage.
Catheter-associated UTIs (CAUTIs)
One of the most common and severe complication that occurs with urinary catheters is a UTI, referred to as a “catheter-associated urinary tract infection” or CAUTI. A Extraluminal.pngCAUTI can lead to urosepsis and septicemia, Infections are common because urethral catheters inoculate organisms into the bladder and promote colonization by providing a surface for bacterial adhesion and causing mucosal irritation. The presence of a urinary catheter is the most important risk factor for bacteriuria. Most bacteria causing CAUTI gain access to the urinary tract either extraluminally or intraluminally.
Extraluminal contamination may occur as the catheter is inserted, by contamination of the catheter from any source. Extraluminal contamination is thought to also occurby microorganisms ascending from the perineum along the surface of the catheter. Most episodes of bacteriuria in catheterized women are believed to occur through the extraluminal entry of organisms. Fecal strains contaminate the perineum and urethral meatus, and then ascend to the bladder along the external surface to cause bacteriuria, catheter biofilm formation, and encrustation. Intraluminal contamination occurs by ascent of bacteria from a contaminated catheter, drainage tube, or urine drainage bag.
Microorganisms can migrate up the catheter into the bladder within 1 to 3 days.
At least 66% of CAUTIs result from extraluminal contamination, whereas 34% are a result of the intraluminal route.
There are three catheter-associated entry points for bacteria:
the urethral meatus, with the introduction of bacteria occurring on insertion of the catheter,
the junction of the catheter-bag connection, especially when a break in the closed catheter system occurs, or
the drainage port of the collection bag.
All 3 of these mechanisms involved in the pathogenesis of colonization and infection of the urinary tract combine to make CAUTI very difficult to prevent in individuals with urinary catheters in place for longer than 2 weeks.
Bacteriuria
Bacteriuria (bacteria in the urine) usually occurs in most patients who have a catheter in place for 2 to 10 days. A large number and a variety of types of organisms are present in the periurethral area and in the distal part of the
Other factors that increase the risk of bacteriuria include the presence of residual urine because of inadequate bladder drainage in the bladder (urine stasis promotes bacterial growth), ischemic damage to the bladder mucosa through overdistention, mechanical irritation from the presence of a catheter, and biofilm formation on the catheter intraluminal surface.
Once a catheter is placed, the daily incidence of bacteriuria is 3 to 10%. Between 10% and 30% of patients who undergo short-term catheterization (i.e., 2 to 4 days) develop bacteriuria and are asymptomatic. Between 90% and 100% of patients who undergo long-term catheterization develop bacteriuria.
About 80% of nosocomial UTIs are related to urethral catheterization; only 5 to 10% are related to genitourinary manipulation. The presence of potentially pathogenic bacteria and an indwelling catheter predisposes to the development of a nosocomial UTI. The bacteria may gain entry into the bladder during insertion of the catheter, during manipulation of the catheter or drainage system, around the catheter, and after removal.
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Catheter-Associated Urinary Tract Infections
A CAUTI is the most common nosocomial infection in hospitals and nursing homes, comprising more than 40% of all institutionally acquired infections.
CAUTIs are considered complicated UTIs and are the most common complication associated with long-term catheter use.
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A CAUTI is more likely to occur in women than men; because of the shorter female urethra and because of the urethra’s close proximity to the anus, bacteria have a shorter distance to travel.
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11 сен 2024
