He believed the future success of his catheter method would come from his theory, in which bacteria were not the only source for infection. Lapides believed that stagnant urine in the bladder could cause very painful bladder infections and UTIs. In addition, he also believed overextension of the bladder with incorrect catheters could also lead to such infections. Despite being widely criticized by many urologists, he persisted with his idea.
Eventually, his technique became the leading method to treat prevalent and chronic diseases, such as urine retention or neurogenic bladder. Up until the late s, insurance companies would only reimburse 4 catheters a month. This was as annoying — and gross — as it sounds. Millions of people around the United States alone had to wash their catheters dozens of times, in order to keep insurance costs low. As one would expect, UTIs and other grueling diseases present from excessive and unsanitary catheter usage soared across the United States.
However, due to the introduction of more cost-effective materials, insurance companies, particularly Medicare, were able to increase reimbursement from 4 catheters a month to catheters a month. This fold increase in the reimbursed catheters provided less infection, discomfort, and worry. Before Foley, Frenchmen Malecot and de Pezzar laid the groundwork with their "four-winged" and "mushroom" models. Before them , Jean Reybard inflated a bladder bag to create the "grandfather" of retained devices.
Catheterization was deemed safe and acceptable, largely because of the antiseptic principles advocated in by Glasgow's Joseph Lister. While skeptics, including some urologists, scoffed at swabbing surfaces prior to procedures, today urologists insist on absolute disinfection to prevent microorganisms from infecting the urinary tract.
Well into the early s, chronic sufferers from bladder outlet obstruction self-catheterized—like Franklin's brother—with concealed catheters they carried on them in hatbands, canes or umbrellas.
But would Listerian procedures be crucial in treating patients with permanent abnormal bladder function? Post-World War II urologists faced that question on a grand scale as ex-soldiers with unprecedented spinal cord injuries returned home as a new catheter population.
These paralyzed patients needed more than occasional treatment for calculi, prostatic obstructions or urethral inflammation. They were treated with catheter drainage of their dysfunctioning bladders. For decades, urologists advocated sterile intermittent techniques because of potential bacteria. But only when University of Michigan urologist Jack Lapides introduced clean intermittent self-catheterization in did it come to light that germs were not the only cause of urinary tract infections UTIs , but that persistent stagnant urinary residuals were also culprits.
Lapides also showed that intermittent catheterization, even if not done in totally sterile conditions, was still safer than an indwelling catheter. The main events in the chronology of the recorded development of the urinary catheter are identified in Table 1. Before the widespread introduction of the Foley catheter [ 14 ] in the s, catheterization was almost exclusively for the treatment of urinary retention in the male.
The early catheters some examples are shown in Figure 1 were usually rigid and they were designed—to the extent that they were designed at all—for intermittent catheterization.
Figure 2 shows what was involved, although most sufferers presumably would have preferred a greater degree of privacy. Urinary retention was—and is—rare in women. Urinary incontinence was not a medical emergency: it was left as a personal embarrassment for men and women alike, who generally adopted their own idiosyncratic methods of coping with the disability.
The indwelling Foley catheter, however, made both short- and long-term catheterization feasible for both males and females and this opened up a new era in the management of urinary retention and incontinence.
Urinary catheterization in the middle ages [ 17 ]. The urinary tract system Figure 3 produces, stores and excretes urine from the body. Urine from the kidneys is transported via the ureters to the bladder. Three sets of muscles control the flow of urine from the bladder via the urethra. The internal sphincter is formed by the involuntary smooth muscle of the bladder wall, located at the base of the bladder where it joins the urethra. The external sphincter which surrounds the proximal part of the urethra is formed by striated muscle and is, thus, under voluntary control.
Third, the pelvic floor muscles act as a sling to support the bladder and urethra and provide additional control. Urine flow is initiated by the voluntary relaxation of the external sphincter muscle which, by reflex action, triggers contraction of the bladder muscle and opening of the internal sphincter. In the normal urinary tract, the regular flushing of the urethra as the bladder empties helps to impede the ascending infection of the tract by the bacteria that normally colonize the periurethral skin.
Any bacteria that manage to migrate into the bladder are also washed out during micturition. In addition, the bladder is lined by urothelial cells coated with a glycosaminoglycan mucin, which provides a surface resistant to the adherence of bacteria. Bacterial adherence, when it does occur, initiates invasion of the urothelium. This activates microbial-sensing proteins in the superficial umbrella cells, triggering the host defences with a cascade of cellular and molecular effectors to eliminate the bacteria [ 18 ].
In people with impaired bladder function, whether retention or incontinence, a safe and reliable system is required to collect and contain the urine, whether for short- or long-term use. In those males and females for whom the method is feasible, clean intermittent self-catheterization is the optimal procedure to manage urinary retention [ 19 ].
This mimics normal bladder function, allowing the bladder to fill and periodically to empty completely, thus minimizing the risk of infection. Although some find the procedure uncomfortable and distasteful, with practice clean intermittent self-catheterization is usually quite easy to perform. Whilst observing a high standard of cleanliness, the patient inserts a flexible catheter typically a plastic tube, with drainage eyes adjacent to its rounded closed tip into the urethra until urine starts to flow, drains the urine directly into a toilet bowl or into a suitable container for later disposal and withdraws the catheter when the flow ceases.
The procedure needs to be repeated six or seven times a day, depending on the volume of residual urine. In the UK, catheters tend to be used only once, but randomized controlled trials are being undertaken to assess whether multiple uses of the same catheter might be acceptable. In a study of adults 68 male, female , seven were unable or unwilling to adopt the technique, but, for the remainder, the mean infection rate was only one per 14 patient-months [ 20 ].
In patients for whom clean intermittent self-catheterization is not possible, an indwelling catheter has to be used. Depending on the clinical indication, the duration of catheterization may be short- or long-term. A long-term urinary catheter is defined as one that is in place for more than 30 days. For male patients with urinary incontinence, one possibility for short- or long-term use is the external or condom catheter.
This consists of a sheath that fits snuggly over the penis and which has a tube at its tip to transport urine to a collection bag, which may be strapped to the leg and emptied periodically. Although this is superficially an attractive approach, it does have several significant disadvantages.
Moreover, the nursing time required for condom catheter care is considerable [ 23 ]. In summary, the condom catheter is far from satisfactory in the management of male urinary incontinence; it does, however, have a useful application in the non-invasive measurement of bladder pressure [ 24 ]. The eponymous indwelling balloon-retained catheter Figure 4 now in worldwide use was conceived by the American urologist Frederic Foley nearly 80 years ago to provide continuous urinary drainage and to control bleeding while haemostasis occurs, following transurethral prostatectomy [ 14 ].
It soon became apparent, however, that the use of the Foley catheter was a solution to the general problems of urinary retention and incontinence. A typical Foley catheter. This catheter is size 16 Fr. The catheter has two channels. When the catheter has been inserted, the retaining balloon is inflated with sterile water from a syringe via the inflation connector and one of the channels.
The inflation connector incorporates a valve to prevent the sterile water from escaping when the syringe is detached. The other channel allows the free flow of urine from the drainage eye to the drainage funnel. To remove the catheter, the retaining balloon is first deflated by withdrawing the water from it with a syringe, which opens the valve in the inflation connector when it is attached. The design of the Foley catheter is simple.
As shown in Figure 4 , the catheter typically has two channels, the drainage channel for the passage of urine and the inflation channel, to allow the balloon at the end of the catheter to be inflated with sterile water from a syringe, to retain the catheter within the bladder. The smooth rounded tip of the catheter extends beyond the balloon and one or more eye-holes are cut in the tube adjacent to the tip to allow urine to drain.
Bladder drainage may be performed by passing a Foley catheter through the natural urethral passage termed transurethral catheterization or by creating an artificial track between the lower abdominal wall and the bladder suprapubic catheterization , as shown in Figure 5. Transurethral catheterization is the simpler and safer approach. Passage of a catheter can be painful and, in the male, the curvature of the urethra introduces a risk that its tip may cause damage [ 25 ].
The main problem with suprapubic catheterization is the risk of perforating the bowel on insertion of the guidance cannula [ 26 ]. Guidelines on minimizing morbidity associated with suprapubic catheter usage have been published by the British Association of Urological Surgeons [ 27 ]. The Foley catheter, introduced a Urethrally and b Suprapubically. In both cases, the bladder is shown to be draining continuously into a urine collection bag attached to the leg: this bag can be emptied when necessary by opening a valve.
Alternatively, the bladder can be drained intermittently if a catheter valve is inserted into the drainage funnel of the catheter. The normal practice is to use the smallest catheter compatible with good drainage [ 28 ]: 12—16 Fr is usually adequate and only rarely is a catheter larger than 18 Fr necessary.
The main problem with latex is its cytotoxicity: for instance, in the s, an epidemic of severe urethral strictures was recorded in patients as the result of using latex catheters.
The cause was traced to cellular toxicity due to eluates from rubber [ 29 ]. Latex catheters are now usually coated with silicone elastomer to reduce this risk [ 30 ].
Many modern catheters are made entirely of silicone elastomer and hydrophilic coatings are used to provide a slippery surface to reduce friction [ 31 ].
Silicone catheters are not only non-allergenic, but they also have superior resistance to kinking and better flow properties in comparison with latex catheters [ 32 ]. Emphasis has also been placed on the need for a smooth surface to the catheter and the drainage eyes [ 33 ]. Rough surfaces encourage the deposition of bacterial biofilm and sharp edges to the drainage eyes can cause bleeding from the urethral lining when the catheter is introduced or withdrawn.
Some catheter research over the last few years has focused on the development of antiseptic and antimicrobial coatings, with the aim of reducing the incidence of catheter-associated urinary tract infections [ 34 ], so far with negligible success [ 35 ] see also Section 6d.
Thus, a randomized controlled trial performed to compare the ability and cost-effectiveness of an antiseptic- and antimicrobial-impregnated catheter vs a standard coated catheter to minimize the risk of catheter-associated urinary tract infection revealed no evidence of benefit [ 36 ]. Indeed, in an earlier randomized clinical trial, infection actually increased with a silver-impregnated catheter [ 37 ].
Some Foley catheters have a third channel, which can be used to infuse saline or other irrigating fluid into the bladder: this may be useful when there is a likelihood that blood clots may form in the bladder, perhaps as the result of post-operative bleeding. There is also a commercially-available catheter that has two balloons at the end of the catheter. The balloon at the tip is intended to reduce the risk of trauma to the urothelium; the drainage eyes perforate a short section of catheter between the two balloons, the proximal of which serves as the retention device.
A possible disadvantage of the dual-balloon catheter is that it may trap more urine in the bladder at the end of drainage, thus increasing the risk of bladder infection. Kunin, published a comprehensive indictment of the Foley catheter, 51 years after its introduction into clinical practice [ 38 ]. Having acknowledged that the Foley catheter is indispensable in modern clinical practice to provide temporary relief of urinary retention, a dry environment for incontinent or comatose patients and an accurate measurement of urinary output in those who are seriously ill, his intervention added momentum to the publication of major contributions covering virtually every aspect of the subject.
For an adverse event to be considered to be serious , it should either: have led to a death; or have led to a serious deterioration in health that either resulted in life-threatening illness or injury or permanent impairment of a body structure or body function, or required in-patient hospitalization or prolongation of existing hospitalization or resulted in medical or surgical intervention to prevent life-threatening illness or injury or permanent impairment of a body structure or a body function; or led to foetal distress, foetal death or a congenital abnormality or birth defect [ 39 ].
The principal adverse events—some of which are serious—for which the Foley catheter is responsible are as follows:. The flow of urine through an indwelling catheter may be continuous or intermittent. The introduction of a Foley catheter without a valve results in continuous drainage and, thereby, suppresses the normal process by which the build-up of bacteria is inhibited by periodic flushing.
Periodic flushing is usually facilitated by a manually-operated pinch or rotary valve. By raising the height of the drainage tubing leading from the catheter to a few centimetres above the level of the bladder, the bladder fills to the corresponding hydrostatic pressure before a syphon is formed that empties the bladder, after which the cycle is repeated.
Although this is a marked improvement and urethral damage can be avoided by suprapubic catheterization [ 42 ], tidal drainage is seldom used nowadays, possibly because of the level of nursing care required.
Bacteria can invade the bladder by migrating along the inside and the outside of the catheter. Urinary tract infection necessitates the use of antibiotics, which are all too frequently untested against the specific bacteria and consequently often prove to be ineffective until the right one is found by a process of trial and error. This adds to the cost of clinical management, as well as being a burden for patients and carers. The use of antibiotics to control catheter-induced infections contributes significantly to the development of resistant strains, about which the World Health Organization WHO has expressed grave concern [ 43 ].
The WHO referred in particular to seven bacteria: the first of these, Escherichia coli , is strongly associated with urinary tract infections. The second bacterium in the list, Klebsiella pneumonia , which is also found in urinary tract infections, was similarly resistant. In view of the increasingly serious threat to global public health identified by the WHO, the present pervasive lack of interest in research aimed at finding a better alternative to the Foley catheter is both disturbing and inexcusable.
This sump of residual urine is likely to be infected, so that uninfected urine descending from the kidneys will also rapidly become infected, resulting in chronic infection of the bladder. Invasion of the bladder by urease-producing bacteria, particularly Proteus mirabilis , results in the conversion of urea in the urine into ammonia [ 35 ]. The consequential increase in the alkalinity of the urine causes phosphates to nucleate out of solution, forming crystals of struvite magnesium ammonium phosphate and hydroxyapatite an hydroxylated form of calcium phosphate in which some of the phosphate groups are replaced by carbonate.
Increasing fluid intake with citrate-containing drinks increases the pH at which crystals form in the urine [ 45 ] and there is evidence [ 46 , 47 ] that this could be used to control the rate at which catheter encrustation occurs.
The nucleation of struvite and hydroxyapatite crystals on the biofilm on the catheter resulting from the activity of the bacterial urease causes encrustation to form around and within the catheter, blocking the drainage eyes and the lumen and preventing the flow of urine Figure 6.
This is a medical emergency that not only can be excruciatingly painful for the patient, but that also and more importantly requires a rapid response usually the replacement of the blocked catheter if permanent damage to the bladder and the kidneys due to ureteric reflux caused by the high bladder pressure is to be avoided.
These problems are exacerbated if associated with bladder spasm [ 48 ]. Moreover, it is apparent that some patients are more likely to block their catheters than others [ 49 ] blockers tend to have urine that is more alkaline, which is consistent with other observations.
A section through a Foley catheter that has become blocked during use by the formation of struvite. The smaller patent lumen is the channel for the inflation and deflation of the retaining balloon. It has been reported that, in cases of Proteus mirabilis infection, the necessity for antibiotics might be avoided by adding the biocide triclosan to the sterile water used to inflate the balloon of the Foley catheter. This appears to prevent the rise in urinary pH that drives biofilm formation and catheter blockage [ 50 ], presumably by leaching into the urine.
It is disappointing, however, that exposure to triclosan has also been shown to encourage the development of resistant strains of Proteus mirabilis , so this does not hold out much promise as a long-term solution [ 51 ]. The crystals of struvite resulting from Proteus mirabilis infection act as nuclei for stone formation within the bladder [ 52 ]. Bladder stones entrap Proteus mirabilis bacteria and, thus, maintain the infection. Recurrent blockage of a catheter raises a high suspicion that bladder stones may be present.
Endoscopic transurethral techniques are used to remove bladder stones: fragmentation by crushing litholapaxy , shock-wave ultrasound or laser probes may be required to break them into particles small enough to be washed out of the bladder through the urethra.
Insertion into the urethra of a hard unyielding catheter, with its balloon and its protruding tip perforated by drainage eyes, transforms the natural process of intermittent drainage. When the drainage valve at the distal end of the catheter is opened, the low viscous drag of the catheter allows the urine to flow rapidly, driven by both the collapsing bladder and the negative pressure of the hydrostatic column to the open end of the catheter.
Request Free Samples. Carr, H. Diokno, A. J Endourol 7 2 : Mattelaer, J. Nacey, J. Curious about intermittent catheterization as an option for draining your bladder? Learn more about the benefits with our latest blog. The Advent of Sterile Catheterization Overall, catheterization was a safe procedure.
The Latest Catheter Technology Today, advancements in catheter technology are leaps and bounds ahead of where we were even just 20 years ago at the cusp of the new century.
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