Most medical practitioners are well aware that few procedures are truly risk-free. While this seems obvious in the case of things like surgeries, treatment isn't the only area of concern when it comes to patient outcomes. Certain diagnostic procedures may also pose risks, making it vital to understand how to mitigate the hazards and optimize the quality of treatment.
Urodynamic studies (UDS) are a prime example of how an overwhelmingly benign procedure nonetheless demands attention to detail and experienced oversight. Here's what to know about UDS, conditions like bacteriuria and urinary tract infections (UTIs), and commonplace risk reduction strategies like the use of prophylactic antibiotics.
Urodynamic Studies and Patient Risks
Urodynamic studies are detailed clinical investigations of the lower urinary tract. They're used to investigate and diagnose problems with the bladder and bowel, and they can help caregivers understand everything from urine retention and sphincter function to transient activity levels in individual muscle groups.
Urodynamic studies typically play a role in diagnosing, assessing, and treating diverse conditions, such as urinary incontinence, retention, and frequency. They are useful in the assessment and treatment process of conditions such as pelvic pain and pelvic organ prolapse (POP).
The versatility of urodynamic studies reflects the fact that tests come in many varieties that can be conducted to minimize invasiveness and discomfort to patients. Technological progress has also resulted in more precise testing procedures. All told, UDS testing is a highly capable method that provides urologists and primary caregivers with extremely valuable insights into patient conditions.
So what's the problem? Well, some studies have established possible links between UDS and bacteriuria, or the presence of bacteria in the urine.
During invasive UDS testing, a catheter is inserted into the bladder, typically through the urethra; however, there are times when other routes, such as a suprapubic tract or mitrofanoff to collect data used to assess bladder function. This can potentially result in tissue damage or the introduction of pathogens into a patient's urinary tract. For instance, one study from 1999 revealed that 7.9 percent of women faced bacteriuria following UDS, although it should be noted that most patients demonstrated asymptomatic infections.
More recent studies have further examined the problem to determine which patients might be at higher risk of developing UTIs or bacteriuria after UDS. A 2015 assessment found that although the incidences of bacteriuria and UTIs were similarly low (11.6 percent and 4.3 percent, respectively) patients with advanced POP or hypothyroidism had higher chances of developing bacteriuria. Also, those with BMIs over 30 faced higher risks of UTIs.
The State of UDS Risk Management
The 2015 study's intent wasn't just to identify risk factors for curiosity's sake. The researchers stated their goal was to help clinicians make better decisions when choosing which patients might be candidates for antibiotic therapy in association with their UDS tests.
Administering prophylactic antibiotics before or immediately after UDS is a common strategy for preventing UTIs. That said, not everyone is an optimal candidate for antibiotics.
In 2017, the Society of Urodynamics, Female Pelvic Medicine, and Urogenital Reconstruction (SUFU) recommendedagainst this course for a range of patients, including individuals lacking genitourinary anomalies and post-menopausal women. It also said clinicians should avoid using antibiotics with those whose clinical histories included:
- Diabetes,
- Recent hospitalizations,
- Obesity,
- Nutritional deficiencies,
- Cardiac valvular disease, or
- Previous genitourinary surgeries.
When it came to deciding which patients should receive antibiotics, SUFU advised this treatment for people with asymptomatic bacteriuria, those over the age of 70, immunosuppression sufferers, and individuals with elevated postvoid residual (PVR) – a sign of improper urinary retention. SUFU also recommended antibiotic prophylaxis for those who have certain medical devices, such as external urine collection devices or indwelling catheters.
So, the official prevailing guidance seems to be that the use of antibiotic prophylaxis should be decided on a case-by-case basis in line with known risk factors. But are clinicians really sticking to this? After all, SUFU's 2017 best practice policy statement was a reactionary effort driven by the already-widespread prevalence of UDS-driven antibiotic administration.
This state of affairs raises a big question: Could clinicians be doing harm by prescribing prophylactic antibiotics in conjunction with UDS and potentially exposing their patients to the subsequent development of antibiotic-resistant infections, allergic reactions, GI upset, or changes in vaginal and urethral flora? The answer isn't as clear as you might assume.
Exploring Research on the Potential Adverse Effects
One 2017 assessment attempted to prove the hypothesis that clinicians could reduce the incidence of UTIs after UDS by giving patients prophylactic antibiotics immediately preceding or following UDS. This analysis gauged a number of studies that compared the use of prophylaxis to placebos or no treatment, focusing on those conducted between 1966 and 2009.
After reviewing the data, the researchers found that the impacts of using antibiotics might be a mixed bag. For instance, although antibiotic prophylaxis was shown to lower the chances of the development of bacteriuria or hematuria (blood in urine) following UDS, the results didn't show that it had the same benefits for symptomatic UTIs. When it came to dysuria, fevers, and adverse reactions, the research uncovered no statistically significant difference between groups.
Ultimately, the researchers in this study seemed to err on the side of caution. Like SUFU, they recommended that the possible benefits of antibiotic prophylaxis should be judged against case-specific factors, like a patient's individual adverse effect likelihood, financial situation, and clinical history.
Another meta-analysis study, conducted in 2021, similarly underscored the value of a conservative approach to prophylaxis in UDS patients. This research encompassed results from thousands of patients across multiple randomized controlled trials and articles. Like the 2017 investigation, it sought to assess whether there were meaningful distinctions between patients that received placebos, no treatments, or antibiotic prophylaxis to prevent the development of UTIs after UDS.
So what did the study discover? On one hand, the team concluded that antibiotic prophylaxis could play a role in reducing asymptomatic bacteriuria as well as symptomatic UTI risk – without raising the likelihood of adverse events. This work also highlighted a few other important realities about the state of knowledge concerning this topic.
This meta-analysis exposed the fact that much of the existing literature suffers from poor methodological quality, such as failing to offer complete data or satisfactorily address potential biases. The meta-analysis itself failed to use research published in languages other than English and Italian, which could present a selective bias.
Apart from these limitations, the study ultimately concluded that antibiotic prophylaxis wasn’t a universally applicable solution, especially because global antimicrobial resistance of pathogens is on the rise. After comparing different types of antibiotic treatment, the researchers also advised that specific caregiving plans should be implemented based on regional data about resistance to antibiotics. It also noted that the problem probably won't be resolved decisively until larger studies take place.
Should Clinicians Use Antibiotics in Conjunction With UDS or Not?
UDS's role in diagnosing such a wide range of problems makes it imperative to understand how associated procedures like the administration of antibiotics might exacerbate or improve the situation. Although most analyses find that the majority of patients do well with prophylaxis in these situations, caregivers need to keep their eyes peeled for risk factors that might contraindicate such solutions.
UTIs may be among the most studied complications of invasive UDS, but the jury is still out on the specifics. For instance, the 2021 meta-analysis found that the incidence of asymptomatic or symptomatic acquired UTIs could be as low as 1.5 percent in some populations or as high as 36 percent in others. Researchers noted several challenges that might contribute to this discrepancy, like age differences, when urine samples were drawn, and even the way UDS and catheterization were performed.
The researchers also said that different studies varied in their definition of what constituted UTIs, which isn't surprising. According to the Alberta Medical Association, in populations like the elderly, chronic genitourinary issues, the high prevalence of asymptomatic bacteriuria, and other comorbidities can make it tough to diagnose UTIs properly.
Even if subsequent research confirms that the hazards of antibiotic treatment are minimal, it's important to remember that patients may have less tolerance for treatment when they believe it carries potentially frightening risks – like UTIs. Because UDS is a diagnostic tool, this hesitancy can potentially make it harder for caregivers to accurately assess what's going on with someone. It's not a bad idea to consider procedures that deliver essential insights while minimizing the odds that something might go awry.
Keeping up with the latest in UDS theory, best practices, and techniques is vital for clinicians that want to promote favorable patient outcomes. Luckily, urologists don't have to tackle this challenge alone.
Today's leading practitioners commonly outsource UDS testing to maintain high standards of care quality and provide full diagnostic services in accordance with prevailing industry wisdom. Many also rely on external training to keep their nurses well-informed on how to perform tests properly to minimize infection risks, reserving antibiotics for the patients who truly need them.
Does your practice need help with conducting safer, more effective diagnostic procedures? Talk to one of our experts about equipping your practice for comprehensive urodynamic testing.
References:
Bombieri, L., Dance, D. A., Rienhardt, G. W., Waterfield, A., & Freeman, R. M. (1999). Urinary tract infection after urodynamic studies in women: incidence and natural history. BJU international, 83(4), 392–395. https://doi.org/10.1046/j.1464-410x.1999.00924.x
Nóbrega, M. M., Auge, A. P., de Toledo, L. G., da Silva Carramão, S., Frade, A. B., & Salles, M. J. (2015). Bacteriuria and urinary tract infection after female urodynamic studies: risk factors and microbiological analysis. American journal of infection control, 43(10), 1035–1039. https://doi.org/10.1016/j.ajic.2015.05.031
Cameron, A. P., Campeau, L., Brucker, B. M., Clemens, J. Q., Bales, G. T., Albo, M. E., & Kennelly, M. J. (2017). Best practice policy statement on urodynamic antibiotic prophylaxis in the non-index patient. Neurourology and urodynamics, 36(4), 915–926. https://doi.org/10.1002/nau.23253
Foon, R., Toozs-Hobson, P., & Latthe, P. (2012). Prophylactic antibiotics to reduce the risk of urinary tract infections after urodynamic studies. The Cochrane database of systematic reviews, 10, CD008224. https://doi.org/10.1002/14651858.CD008224.pub2
Wu, X. Y., Cheng, Y., Xu, S. F., Ling, Q., Yuan, X. Y., & Du, G. H. (2021). Prophylactic Antibiotics for Urinary Tract Infections after Urodynamic Studies: A Meta-Analysis. BioMed research international, 2021, 6661588. https://doi.org/10.1155/2021/6661588