What Is Straight Catheterization: Procedure and Uses

Straight catheterization is the brief insertion of a thin, flexible tube through the urethra into the bladder to drain urine, followed by immediate removal once the bladder is empty. Unlike an indwelling (Foley) catheter, which stays in place for hours or days with a small balloon holding it inside, a straight catheter goes in and comes out within minutes. This “in-and-out” approach is one of the most common procedures in clinical medicine, used after surgery, during hospital stays, and as a long-term self-care routine for people who cannot fully empty their bladders on their own.

How the Procedure Works

The basic steps are straightforward, whether performed by a nurse, a doctor, or the person themselves. The area around the urethral opening is cleaned, a lubricant is applied to the catheter tip, and the catheter is gently advanced through the urethra until urine begins to flow. Once the bladder is drained, the catheter is slowly withdrawn. The entire process takes a few minutes in most cases. A study comparing bladder-volume measurement methods found that catheterization averaged about five minutes per event, ranging from roughly two to eleven minutes depending on the patient and circumstances.¹

For women, the catheter passes through a short urethra directly into the bladder. For men, the catheter must travel through a longer urethra that curves around the prostate gland, which is why adequate lubrication and a gentle technique matter. The reported incidence of urethral injury during catheterization in males is roughly 13 per 1,000 procedures, with common causes including poor technique, insufficient lubrication, and inflating a balloon before the catheter is properly positioned (a concern specific to indwelling catheters, not straight ones).²

When and Why Straight Catheterization Is Used

The procedure serves two broad purposes: measuring how much urine the bladder holds after someone tries to void (called post-void residual measurement) and relieving urinary retention when someone physically cannot empty their bladder. The specific situations vary widely.

Post-operative retention: After surgery, especially procedures involving the pelvis or lower limbs, anesthesia and pain medications can temporarily shut down normal bladder function. A study of elderly women who developed urinary retention after hip-fracture surgery found that intermittent catheterization two or three times daily restored normal voiding in ten of eleven patients, and the researchers concluded it was safer and more practical than leaving a catheter in place during rehabilitation.³
Neurogenic bladder: People with spinal cord injuries, spina bifida, multiple sclerosis, or other neurological conditions often lose the ability to sense bladder fullness or coordinate the muscles needed for urination. For many of these individuals, straight catheterization performed several times a day becomes a permanent part of life.
Acute retention in the hospital: A clinical panel published in JAMA Network Open developed volume-based guidelines for when catheterization is appropriate. For patients experiencing symptoms like pain or pressure, intermittent straight catheterization was deemed appropriate at lower bladder volumes than placing an indwelling catheter. For patients without symptoms, catheterization of any kind was considered inappropriate when bladder volume was below 400 mL, while volumes of 500 mL or more warranted drainage.⁴
Urine specimen collection: When a clean-catch urine sample is not possible or reliable, a quick straight catheterization provides a sterile specimen directly from the bladder for culture or testing.

How It Compares to an Indwelling Catheter

The indwelling Foley catheter, which stays inside the bladder and drains continuously into a bag, became widely available in the 1930s and opened up long-term bladder management for both men and women.⁵ It remains indispensable in certain situations, such as critically ill patients who need precise urine output monitoring. But for many people, intermittent straight catheterization is preferred because it allows the bladder to fill and empty in a more natural cycle, avoids the constant foreign body sitting inside the bladder, and gives the person more freedom between catheterizations.

A comparison study found that infection rates at any single visit were the same for both approaches, about 8% of patients using indwelling catheters and 8% using intermittent catheterization showing a urinary tract infection at the time of assessment.⁶ That may seem surprising given the common belief that indwelling catheters carry higher infection risk, but the indwelling-catheter group in that study was also older and sicker on average. In older women recovering in rehabilitation settings, intermittent catheterization and indwelling catheters have shown similar success rates for regaining normal voiding and similar rates of bacteria in the urine, but researchers have noted that the presence of an indwelling catheter can hinder rehabilitation and affect quality of life in ways that intermittent catheterization does not.⁷

Quality-of-life research reinforces this preference. A review of neurogenic-bladder patients found that those who performed self-catheterization tended to report higher overall quality of life than those relying on other bladder management methods, with normal urination combined with self-catheterization yielding the best outcomes.⁸

Infection Risk and What Drives It

Urinary tract infections are the main complication of any catheterization method, and they remain a significant concern for people who catheterize regularly. In a study of spinal cord injury patients performing intermittent catheterization, about two-thirds were eventually placed on preventive treatment for recurrent symptomatic infections, and roughly a quarter had three or more positive urine cultures in a single year.⁹ That paints a realistic picture: intermittent catheterization lowers infection risk compared with a catheter that never leaves, but it does not eliminate it.

Research into what increases infection risk has identified several practical factors. In community-dwelling spinal cord injury patients in China, risk factors included difficulty inserting the catheter, frequent urinary incontinence, switching to other bladder-emptying methods, and reusing catheters.¹⁰ In children with neurogenic bladder, starting catheterization late, doing it too infrequently, and having underlying anatomical issues like vesicoureteral reflux all raised the odds of febrile infections.¹¹ The takeaway from these studies is that technique, timing, and frequency matter at least as much as the catheter itself.

Clean Technique Versus Sterile Technique

In a hospital, catheterization is typically performed with sterile gloves, sterile equipment, and antiseptic cleaning. But when people catheterize themselves at home multiple times a day, full sterile technique is impractical. The standard home approach is “clean” technique: washing hands thoroughly, using a clean (not necessarily sterile) catheter, and lubricating before insertion. A study comparing clean and sterile intermittent catheterization in a nursing home setting found no significant differences between the two groups in the number of infections, the time until the first infection, the types of bacteria cultured, or the cost of antibiotic treatment.¹² Clean technique has been the accepted standard for home use since the 1970s, and the evidence continues to support its safety.

Catheter Types and Why They Matter

Not all straight catheters are the same. The basic uncoated catheter requires the user to apply a separate lubricant before insertion. Hydrophilic-coated catheters come with a built-in slippery surface that activates with water, creating a lubricated layer along the entire length. A third option is a pre-lubricated catheter that comes ready to use in a sealed package.

The coating makes a measurable difference. A randomized crossover trial found that hydrophilic-coated catheters produced less friction during withdrawal, caused less microscopic bleeding, and were less painful than gel-lubricated uncoated catheters. About 93% of participants in that study preferred the hydrophilic option.¹³ A broader scoping review confirmed that hydrophilic catheters caused discomfort in about 30% of users compared with 55% for uncoated catheters, and the smoother surface reduced the risk of micro-trauma to the urethral lining.¹⁴

Catheters also come in different lengths and French sizes (a measure of diameter). Women can typically use shorter catheters, while men need standard-length ones. Pediatric sizes are smaller in diameter. Getting the right size matters: too small and urine drains slowly; too large and insertion is uncomfortable.

Managing Pain and Discomfort

Straight catheterization is uncomfortable for most people, especially the first few times. In clinical settings, the question of whether lidocaine gel (a numbing agent) helps has been studied in different populations with mixed results. A randomized trial in adult women found that lidocaine gel significantly reduced pain compared with plain lubricant: about 62% of women in the lidocaine group reported any pain versus 81% in the plain-gel group, and pain scores were roughly half as high.¹⁵

The picture is different in young children. A randomized trial found that 2% lidocaine gel did not meaningfully reduce pain scores during bladder catheterization compared with standard lubricant, likely because the distress of the procedure itself overwhelms any local numbing effect.¹⁶ For children, distraction techniques and having a calm, experienced caregiver perform the procedure tend to matter more than the choice of lubricant.

For people who self-catheterize daily, comfort typically improves with practice. The first week is usually the hardest, and many people report that within a few weeks the process becomes routine, especially with hydrophilic catheters that minimize friction.

Catheterization in Children

Children with spina bifida and other causes of neurogenic bladder are one of the largest groups who depend on regular intermittent catheterization. A scoping review identified key barriers and facilitators for these families. Barriers included pain, stigma and fear, inaccessible public restrooms, difficulty obtaining the right catheter sizes, and limited quality of initial training. Facilitators that made the routine more manageable included starting catheterization early in infancy, consistent follow-up with healthcare providers, family and community support, good-quality initial teaching, and the use of lubricants.¹⁷

One of the practical milestones for children on long-term catheterization is learning to do it themselves. A study of children with spina bifida found that 76% learned to perform catheterization independently, at an average age of about 8 years, with a range from roughly 5 to 15 years old.¹⁸ Gaining independence in this skill is a significant moment for the child’s self-confidence and participation in school and social activities. Parents and clinicians often work together to build the child’s competence gradually, starting with having the child help with setup and cleaning before progressing to full self-catheterization.

Adaptive Devices for People With Limited Hand Function

Self-catheterization requires a surprising amount of dexterity: opening a package, gripping a thin flexible tube, guiding it into place, and managing clothing, all while positioned on a toilet or in a wheelchair. For people with spinal cord injuries at the cervical level (who have limited or absent hand function), this can seem impossible without help. Fortunately, a range of adaptive tools exist. These include catheter handle grips designed for specific levels of hand function, leg spreaders with mirrors for better visualization, labial spreaders to help women access the urethra, and clothing retractors or adaptive garments.¹⁹

One example is a device called the HouseHold, designed specifically for men with tetraplegia. In a study, all participants were able to perform every step of catheterization independently within five minutes on their very first attempt using the device. At one-month follow-up, all but one continued using it, with the exception being someone who regained enough hand function to manage without it.²⁰ These tools are not widely known, and many people with limited hand function are never told about them, so bringing them up with an occupational therapist or urologist is worth doing.

Using Bladder Scanners to Reduce Unnecessary Catheterization

Every catheterization carries some risk of infection or discomfort, so skipping it when the bladder is not actually full is a practical win. Portable ultrasound bladder scanners allow a nurse or the person themselves to check bladder volume in under a minute without inserting anything. A study found that the BladderScan device gave accurate measurements of post-void residual urine in all subjects tested, averaging about 45 seconds per scan compared with roughly five minutes for catheterization. The researchers concluded that scanning first could meaningfully reduce the frequency of catheterization, saving time, discomfort, and healthcare costs.¹ In hospitals, bladder scanners are now standard in many post-surgical units precisely for this reason: if the scan shows less than 300 to 400 mL of urine, catheterization can be safely deferred.

The Cost and Environmental Side of Catheter Use

For people who catheterize four to six times a day, catheter supply becomes a major logistical and financial consideration. In many countries, single-use catheters are the standard recommendation, meaning an individual might go through well over a thousand catheters per year. A cost-effectiveness analysis found that combining reusable catheters with single-use ones (rather than using single-use exclusively) saved roughly £1,350 per patient per year with no meaningful difference in health outcomes.²¹ Another review confirmed that single-use catheters are more expensive and have a greater environmental footprint than reusable alternatives.²²

The environmental numbers are striking. Assuming five catheterizations a day across the population that uses them, single-use catheters generate an estimated 85 million pounds of waste per year in the United States alone, filling the equivalent of 80 Olympic swimming pools. The most common catheter materials, primarily PVC and silicone, show little to no degradation once they reach a landfill.²³ Despite this, and despite the economic data favoring a mixed approach, single-use remains the dominant recommendation in many healthcare systems, largely because regulatory and reimbursement structures favor disposable products. In low-resource settings around the world, catheter reuse is the norm out of necessity, and studies in those contexts have not shown the feared spike in infections, though cleanliness of the reuse process is critical.²⁴

Learning Self-Catheterization

The prospect of catheterizing yourself for the first time is daunting for most people. The training usually happens with a continence nurse or urologist who walks you through the anatomy, demonstrates the technique on a model, and then guides you through your first self-catheterization in a clinical setting where help is immediately available. Most people can perform the procedure independently after one to three supervised sessions, though comfort and confidence build over weeks.

Positioning varies by preference and physical ability. Some people catheterize sitting on the toilet, others while lying in bed, and wheelchair users may develop their own adapted positions. Women sometimes use a mirror initially to locate the urethral opening until they can do it by feel. Men need to hold the penis at a specific angle to straighten the urethral path. None of this is intuitive at first, and it is completely normal to need several attempts. The key message that experienced continence nurses emphasize is that it gets easier, and the anxiety of anticipation is almost always worse than the procedure itself.