Suprapubic bladder aspiration with or without ultrasound guidance

Evidence-based clinical practice guideline for management of urinary tract infection and primary vesicoureteric reflux

We present updated, evidence-based clinical practice guidelines from the Indian Society of Pediatric Nephrology (ISPN) for the management of urinary tract infection (UTI) and primary vesicoureteric reflux (VUR) in children. These guidelines conform to international standards; Institute of Medicine and AGREE checklists were used to ensure transparency, rigor, and thoroughness in the guideline development. In view of the robust methodology, these guidelines are applicable globally for the management of UTI and VUR. Seventeen recommendations and 18 clinical practice points have been formulated. Some of the key recommendations and practice points are as follows. Urine culture with > 104 colony forming units/mL is considered significant for the diagnosis of UTI in an infant if the clinical suspicion is strong. Urine leukocyte esterase and nitrite can be used as an alternative screening test to urine microscopy in a child with suspected UTI. Acute pyelonephritis can be treated with oral antibiotics in a non-toxic infant for 7-10 days. An acute-phase DMSA scan is not recommended in the evaluation of UTI. Micturating cystourethrography (MCU) is indicated in children with recurrent UTI, abnormal kidney ultrasound, and in patients below 2 years of age with non-E. coli UTI. Dimercaptosuccinic acid scan (DMSA scan) is indicated only in children with recurrent UTI and high-grade (3-5) VUR. Antibiotic prophylaxis is not indicated in children with a normal urinary tract after UTI. Prophylaxis is recommended to prevent UTI in children with bladder bowel dysfunction (BBD) and those with high-grade VUR. In children with VUR, prophylaxis should be stopped if the child is toilet trained, free of BBD, and has not had a UTI in the last 1 year. Surgical intervention in high-grade VUR can be considered for parental preference over antibiotic prophylaxis or in children developing recurrent breakthrough febrile UTIs on antibiotic prophylaxis.

Point-of-care ultrasound for non-vascular invasive procedures in critically ill neonates and children: current status and future perspectives

Point-of-care ultrasound (POCUS) has been established as an essential bedside tool for real-time image guidance of invasive procedures in critically ill neonates and children. While procedural guidance using POCUS has become the standard of care across many adult medicine subspecialties, its use has more recently gained popularity in neonatal and pediatric medicine due in part to improvement in technology and integration of POCUS into physician training programs. With increasing use, emerging data have supported its adoption and shown improvement in pediatric outcomes. Procedures that have traditionally relied on physical landmarks, such as thoracentesis and lumbar puncture, can now be performed under direct visualization using POCUS, increasing success, and reducing complications in our most vulnerable patients. In this review, we describe a global and comprehensive use of POCUS to assist all steps of different non-vascular invasive procedures and the evidence base to support such approach.

CONCLUSION

There has been a recent growth of supportive evidence for using point-of-care ultrasound to guide neonatal and pediatric percutaneous procedural interventions. A global and comprehensive approach for the use of point-of-care ultrasound allows to assist all steps of different, non-vascular, invasive procedures.

WHAT IS KNOWN

• Point-of-care ultrasound has been established as a powerful tool providing for real-time image guidance of invasive procedures in critically ill neonates and children and allowing to increase both safety and success.

WHAT IS NEW

• A global and comprehensive use of point-of-care ultrasound allows to assist all steps of different, non-vascular, invasive procedures: from diagnosis to semi-quantitative assessment, and from real-time puncture to follow-up.

Strengthening the success rate of suprapubic aspiration in infants by integrating point-of-care ultrasonography guidance: A parallel-randomized clinical trial

BACKGROUND

Urinary tract infection (UTI) is a common disease in childhood. A sterile collection of urine samples using suprapubic aspiration (SPA) and bladder catheterization (BC) is helpful for rapid and accurate diagnosis of UTI in infants. With the advent of point-of-care ultrasound (POCUS), the use of ultrasound by non-radiologists at the patient's bedside, great advancement has been noticed in various medical fields. Considering the importance and advantages of using POCUS in the physical examination and guiding procedures, the authors aimed to compare urine sampling's success rate by SPA, BC, and POCUS guided SPA (POCUS-SPA) in infants performed by three pediatricians.

MATERIALS AND METHODS

This study is a randomized clinical trial conducted on 114 neonates and infants with suspected UTI admitted to 17-Shahrivar children's hospital from April 2017 to September 2019. Neonates and infants were randomly assigned to three groups of BC, SPA, and POCUS-SPA. The primary outcome was the success of sampling defined by obtaining 1cc of urine in each method. The secondary outcome was assessing the pain level.

RESULTS

Results showed that the POCUS-SPA had the highest success rate in urine sampling, and a statistically significant relation was noted among the three groups (P = 0.0001). From 38 patients in each group, 37 patients of POCUS-SPA (97.4%), 34 patients of BC (89.5%), and 23 patients of SPA (60.5%) had a successful sampling. Most of the patients in all three groups experienced severe pain.

CONCLUSIONS

In the current study, results showed that the POCUS-SPA significantly increased the success rate of urine sampling and most of the patients in all three groups had severe pain. Based on the shortage of access to radiologists in emergency setups, it seems that the POCUS-SPA by the pediatricians can be one of the most appropriate and applicable diagnostic methods in infants with UTI.

Urine collection methods and dipstick testing in non-toilet-trained children

Urinary tract infection is a commonly occurring paediatric infection associated with significant morbidity. Diagnosis is challenging as symptoms are non-specific and definitive diagnosis requires an uncontaminated urine sample to be obtained. Common techniques for sampling in non-toilet-trained children include clean catch, bag, pad, in-out catheterisation and suprapubic aspiration. The pros and cons of each method are examined in detail in this review. They differ significantly in frequency of use, contamination rates and acceptability to parents and clinicians. National guidance of which to use differs significantly internationally. No method is clearly superior. For non-invasive testing, clean catch sampling has a lower likelihood of contamination and can be made more efficient through stimulation of voiding in younger children. In invasive testing, suprapubic aspiration gives a lower likelihood of contamination, a high success rate and a low complication rate, but is considered painful and is not preferred by parents. Urine dipstick testing is validated for ruling in or out UTI provided that leucocyte esterase (LE) and nitrite testing are used in combination.

How to… collect urine samples from young children

Urine samples are commonly collected from young children to diagnose or exclude urinary tract infections, but collection from precontinent children is challenging. Each collection method has advantages and limitations. Non-invasive methods (urine pads, bags, clean catch) are convenient but can be time-consuming and are limited by sample contamination. Voiding stimulation methods (bladder-lumbar stimulation, Quick-Wee) can expedite clean catch collection. Invasive methods (catheter, suprapubic aspiration) can be more reliable, but require expertise to perform and cause pain for the child. This article reviews each collection method, and describes collection procedures, indications and strategies to optimise success and reduce contamination.

Liquid gold: the cost-effectiveness of urine sample collection methods for young precontinent children

BACKGROUND

Urinary tract infection (UTI) is a common childhood infection. Many febrile children require a urine sample to diagnose or exclude UTI. Collecting urine from young children can be time-consuming, unsuccessful or contaminated. Cost-effectiveness of each collection method in the emergency department is unknown.

OBJECTIVE

To determine the cost-effectiveness of urine collection methods for precontinent children.

METHODS

A cost-effectiveness analysis was conducted comparing non-invasive (urine bag, clean catch and 5 min voiding stimulation for clean catch) and invasive (catheterisation and suprapubic aspirate (SPA)) collection methods, for children aged 0-24 months in the emergency department. Costs included equipment, staff time and hospital bed occupancy. If initial collection attempts were unsuccessful subsequent collection using catheterisation was assumed. The final outcome was a definitive sample incorporating progressive dipstick, culture and contamination results. Average costs and outcomes were calculated for initial collection attempts and obtaining a definitive sample. One-way and probabilistic sensitivity analyses were performed.

RESULTS

For initial collection attempts, catheterisation had the lowest cost per successful collection (GBP£25.98) compared with SPA (£37.80), voiding stimulation (£41.32), clean catch (£52.84) and urine bag (£92.60). For definitive collection, catheterisation had the lowest cost per definitive sample (£49.39) compared with SPA (£51.84), voiding stimulation (£52.25), clean catch (£64.82) and urine bag (£112.28). Time occupying a hospital bed was the most significant determinant of cost.

CONCLUSION

Catheterisation is the most cost-effective urine collection method, and voiding stimulation is the most cost-effective non-invasive method. Urine bags are the most expensive method. Although clinical factors influence choice of method, considering cost-effectiveness for this common procedure has potential for significant aggregate savings.

Genitourinary Procedures

Emergency medicine providers may encounter serious GU conditions that need rapid diagnosis and early intervention to avoid severe life- and limb-threatening complications. A fundamental knowledge of several key procedural interventions is incredibly important to optimal patient outcomes.

Success rate of BladderScan-assisted suprapubic aspiration

OBJECTIVE

Suprapubic aspiration (SPA) is the gold standard for obtaining uncontaminated urine specimens in young febrile children. The use of real-time ultrasound (RTUS) has been shown to increase the success rate of SPA. The BladderScan (BSUS) Verathon(®) is an alternative portable ultrasound device designed to provide automated measurement of bladder volume. Although simple and requiring minimal training, there are no data on the success rate of SPA using the device.

METHODS

An audit of current SPA practice using BSUS in the ED of a tertiary referral children's hospital was conducted. We assessed the success rate of SPA to obtain urine and correlate with BSUS readings and techniques.

RESULTS

Sixty SPAs (mean age 5.0 months) were observed over an 8-month period between August 2009 and March 2010. The audit showed an overall success rate of 53% (32/60) [95% confidence interval 41-66%]. Success rates were 63%, 32%, 82% and 63% for the largest BSUS readings of 0-9 mL (n = 8), 10-19 mL (n = 25), 20-29 mL (n = 11) and 30+ mL (n = 16), respectively, or 39% at <20 mL and 70% at ≥20 mL (P = 0.02).

CONCLUSION

The success rate of SPA in 'real-life' non-standardised clinical practice was low at 53% overall. The BSUS-assisted SPA success rate was higher in patients with readings ≥20 mL. These rates are lower than success rates reported using RTUS. Parameters for using BSUS to assist SPA should be established.

Assessing bladder volumes in young children prior to instrumentation: accuracy of an automated ultrasound device compared to real-time ultrasound

OBJECTIVES

Automated bladder ultrasound (ABUS) devices are portable and designed to provide automated measurement of bladder volume. They are simple and require minimal training compared to conventional real-time ultrasound (RTUS). Their most common application in the acute pediatric setting is to assess bladder volumes prior to performing invasive urine collection such as suprapubic aspiration (SPA) in children younger than 2 years of age. However, data on ABUS in young children are limited. The aim of this study was to assess the repeatability and accuracy of one type of ABUS, the BladderScan, in measuring of bladder volume in children aged 0 to 24 months when compared with RTUS.

METHODS

Healthy children aged 24 months and younger were scanned twice, 1 hour apart, using ABUS and RTUS. ABUS readings were performed by two senior pediatric emergency physicians who both completed three readings for each child. The measurements were repeated using a second ABUS machine in case of machine variability. RTUS measurements were performed by a pediatric sonographer who was blinded to the ABUS results. ABUS and RTUS measurements were compared by Bland-Altman analysis to determine the repeatability coefficient (repeatability) and the limits of clinical agreement (accuracy).

RESULTS

Bladder volume measurements were performed on 61 children aged 0 to 24 months (31 males; mean ± SD = age 11 ± 6.2 months; range = 0 to 24 months) using both the ABUS and the RTUS. There was wide variation between ABUS and RTUS measurements. The repeatability coefficient within ABUS readings was 20 mL. By Bland-Altman analysis, the 95% limits of agreement between ABUS and RTUS were -31 to +19 mL. ABUS also detected no values between 0 and 10 mL.

CONCLUSIONS

This study showed poor repeatability and accuracy in bladder volume measurements using BladderScan ABUS when compared to RTUS. The ABUS method does not appear to be a reliable method for assessing bladder volumes in children aged 0 to 24 months prior to bladder instrumentation.

A comparative study on bacterial cultures of urine samples obtained by clean-void technique versus urethral catheterization

Contamination during urine collection causes difficulty in diagnosing infantile urinary tract infection (UTI). Though considered a gold-standard, suprapubic aspiration is traumatic and not always successful. Catheterization and clean void technique were often preferred but their relative usefulness has not been compared.

OBJECTIVES

To compare the culture results of clean void urine (CVU) and catheter urine (CathU) from children below 2-years old known to have no UTI. We tested whether the false-positive rates of CVU were significantly different from that of CathU.

METHODS

Paired CVU and CathU samples were collected from asymptomatic children admitted for micturiting cystourethrogram, and tested for leucocytes and nitrite, and bacterial culture using standard laboratory methods.

RESULTS

Culture results for 98 children (82 boys, 16 girls; aged 6 +/- 4.3 months) were analysed. Analysis by presence/absence of growths showed good agreement between CVU and CathU for boys (Kappa 0.42) but poor for girls (Kappa 0.18). When analysed by colony counts, agreement was poor with CVU yielding more counts than CathU (Kappa 0.1 for boys and 0.04 for girls). If all mixed growth results were considered as contaminants, the false positive rates for CathU and CVU were similar whether the cut-off was defined as 10(3), 10(4) or 10(5)/mL. If mixed growth was believed to cause UTI, CathU produced less false-positive rates than CVU, though both rates were unacceptably high.

CONCLUSION

In uncircumcized boys, both CVU and CathU were prone to contamination. Though the contaminating bacterial counts were lower in CathU culture, the false-positive rates were high with the lower cut-off CFUs. Contrary to previous recommendations, CathU should be interpreted similar to CVU to avoid false positive diagnosis of UTI.

Novel applications of ultrasound in pediatric emergency medicine

A new field, termed emergency ultrasound (EUS), has recently been established. The past decade saw rapid development in the field of EUS in adult patients, especially as performed by emergency medicine physicians. Ultrasound imaging offers several advantages over traditional radiographic techniques, many of which are especially relevant to patients in the pediatric emergency department. Recent literature has documented increased use of EUS for pediatric patients. This review will examine basic principles of ultrasound relevant to pediatric emergency medicine physicians. Emphasis will be placed on understanding the instrument and its limitations. In addition, we will review recent developments in this field. It is our goal that the reader will gain an understanding of the strengths and limitations of this instrument and will therefore be in a position to plan their own program in EUS in pediatrics. Furthermore, it is hoped that this review will serve as an impetus for innovative research, to refine and extend the indications of this modality to benefit patients in the pediatric emergency department.

Suprapubic bladder tap aspiration in an elderly female

Suprapubic bladder aspiration is a rarely used technique for obtaining urine samples in the adult Emergency Department (ED). We report a case of an elderly woman in whom suprapubic aspiration (SPA) was safely performed using bedside ultrasound guidance. More conventional urine collection methods were precluded by the constraint on positioning imposed by the patient's flexion contractures. Ultrasound-guided SPA is a safe technique, that probably should be employed more frequently in the adult ED.

Diagnosing symptomatic urinary tract infections in infants by catheter urine culture

BACKGROUND

Diagnosing infantile urinary tract infection (UTI) is difficult due to contamination during urine collection. Catheterization is convenient but diagnostic criteria (colony-forming units per millilitre (CFU/mL)) is controversial, especially in uncircumcised males.

OBJECTIVES

To study the value of catheter urine cultures in terms of likelihood ratios (LRs), sensitivity, specificity, positive and negative predictive values of different CFU/mL in uncircumcised boys and girls.

METHODS

Infants aged 1-18 months who had catheter urine cultures from July 1999 to June 2002 were reviewed to decide if they had symptomatic UTI (group A) or not (group B). Urinary tract infection was confirmed if patients had a positive urine culture plus acute fever, pyuria, positive leucocyte esterase and nitrite tests and good response to antibiotics, with pyelonephritic evidence on early dimercaptosuccinic acid (DMSA) scans in doubtful cases. Group B included infants with negative urine culture results, and those with positive results but were asymptomatic and admitted for micturating cystourethrogram.

RESULTS

Nine hundred and fifty-two patients were studied (492 boys, 460 girls; 212 in group A, 740 in group B). No single cut-off CFU/mL has high sensitivity and specificity to simultaneously diagnose and exclude UTI. The CFU counts of 100-10(3), 10(3)-10(4), 10(4)-10(5) and >10(5) were associated with LRs of 0.11, 0.45, 1.52 and 20.5, respectively in uncircumcised boys, and with LRs of 1.39, 2.49, 8.95 and 18.8, respectively in girls. The LR for mixed growths was 0.21.

CONCLUSION

Unlike suprapubic tap urine, catheter urine culture has to be interpreted against the clinical context or pretest probability and in terms of probability. In the scenario of a febrile infant where the pretest probability of UTI was about 5%, UTI was highly likely if counts exceeded 10(5)/mL, and unlikely if counts were below 10(4)/mL in uncircumcised boys. In female infants, UTI was highly likely if counts were >10(4) CFU/mL, but lower counts could not exclude UTI.

Procedural applications of ultrasound

Many invasive procedures are now safer and more efficient with the use of ultrasound guidance. As emergency physicians continue to develop skills in sonography, new applications of this technology will continue to impact the practice of emergency medicine.

Use of ultrasound to improve the safety of postgraduate training in obstetrics and gynaecology

Supervised clinical work is perhaps the most valuable component of postgraduate training and has a long-term impact. Senior clinicians not only take the responsibility of teaching and supervising junior doctors but also most of them take the consequences of any clinical failures or mistakes associated with the training. Despite the introduction of simulators and computer-assisted learning, practice on real patients is still required to learn many skills in obstetrics and gynaecology. Training must be safe, because trainees or trainers must not put our patients at risk as part of the process of learning to heal others. Ultrasound can be used to demonstrate and guide several procedures that have been performed 'blindly' in the past. This technology can reduce the risks associated with training and supervision of junior doctors.