Division of Pediatric Urology, Department of Pediatric Surgery, Montreal Children's Hospital, McGill University, Montreal, Quebec, Canada.
Division of Urology, Department of Surgery, Jewish General Hospital, McGill University, Montreal, Quebec, Canada.
J Pediatr Urol. 2023 Oct;19(5):541.e1-541.e7. doi: 10.1016/j.jpurol.2023.07.004. Epub 2023 Jul 21.
Little is known about the effect of catheterization during pressure-flow studies (PFS) on voiding efficiency in children. Our objective was to determine the effect of urethral catheterization on Qmax and flow index (FI) during PFS compared to the free flow of uroflowmetry (UF).
We retrospectively reviewed 63 consecutive children who underwent UF and PFS at our center on the same day (2019-2022). Voiding data was available for 46 patients. Patients first underwent a UF with full bladder, then PFS after urethral catheter insertion. Patients with urethral pathologies (n = 6), on clean intermittent catheterization (CIC) (n = 2) and with major comorbidities (n = 2) were excluded. Indications for UF/PFS were LUTS, recurrent UTIs, incontinence or neurosurgical pre-operative evaluation. Data was collected from the UF and the PFS and compared using paired t-test. The idealized Qmax and flow index (FI) were calculated for UF and PFS using the formulas described by Franco et al.: Male Qmax = 11.26 + 0.0701(TBC [total bladder capacity]) - 0.0000513(TBC); Female Qmax = 10.723 + 0.073(TBC) - 0.0000423(TBC), FI = Actual Qmax/Expected Qmax (Franco and et al., 2016; Franco et al., 2018; Franco and et al., 2016).
Median age was 7 years old (IQR 5-11). Twenty-one (40%) patients were male and 32 (60%) patients were female. Of the 53 patients, 3 boys and 4 girls (n = 7; 13%) were unable to void with the catheter in place during PFS but able to void after its removal. Of the remaining 46 cases, the Qmax during PFS was 5 mL/s slower than the Qmax recorded on the UF without catheter, representing a decrease of 29% (12.3 vs 17.3 mL/s; p < 0.0001). The impact of urethral catheter during PFS was more important in males vs females (Qmax decreased by 7.7 vs 3.3 mL/s, or 45 vs 19%). The mean FI during PFS was 44%, which was a 30% reduction compared to the 74% FI obtained with UF (p < 0.00001). In males, the FI decreased by 37% on PFS, whereas it decreased 26% in females, similar to the Qmax decrease.
Voiding efficiency, as assessed by Qmax and FI, is decreased during PFS compared to uroflow studies. Our data documents for the first time the impact of urethral catheterization on pediatric voiding efficiency. Abnormal flow rates and elevated PVRs should be used to guide patient management only if obtained by uroflow. Prospective validation comparing free flow with PFS studies will help characterize the impact of urethral catheter relative to bladder pathology, age, gender and catheter size used.
关于在压力-流率研究（PFS）期间行导尿对儿童排尿效率的影响知之甚少。我们的目的是确定与尿流率（UF）自由流相比，PFS 期间导尿对最大尿流率（Qmax）和流量指数（FI）的影响。
我们回顾性分析了 2019 年至 2022 年在我院同一天接受 UF 和 PFS 的 63 例连续患儿。46 例患者有完整的排尿数据。患者首先进行完全膀胱充盈的 UF，然后在插入尿道导管后进行 PFS。排除有尿道病变（n=6）、清洁间歇性导尿（CIC）（n=2）和主要合并症（n=2）的患者。UF/PFS 的指征为 LUTS、复发性尿路感染、尿失禁或神经外科术前评估。使用配对 t 检验比较 UF 和 PFS 中的数据。使用 Franco 等人描述的公式为 UF 和 PFS 计算理想的 Qmax 和 FI：男性 Qmax=11.26+0.0701（TBC[总膀胱容量]）-0.0000513（TBC）；女性 Qmax=10.723+0.073（TBC）-0.0000423（TBC），FI=实际 Qmax/预期 Qmax（Franco 等人，2016 年；Franco 等人，2018 年；Franco 等人，2016 年）。
中位年龄为 7 岁（IQR 5-11）。21 名（40%）患者为男性，32 名（60%）患者为女性。在 53 名患者中，3 名男孩和 4 名女孩（n=7；13%）在 PFS 期间无法在放置导尿管的情况下排尿，但在取出导尿管后可以排尿。在其余 46 例中，PFS 期间的 Qmax 比无导尿管 UF 记录的 Qmax 慢 5ml/s，减少了 29%（12.3 vs 17.3 ml/s；p<0.0001）。在男性中，导尿管对 PFS 的影响大于女性（Qmax 分别减少了 7.7 和 3.3 ml/s，或 45%和 19%）。PFS 期间的平均 FI 为 44%，与 UF 获得的 74% FI 相比，减少了 30%（p<0.00001）。在男性中，PFS 期间 FI 减少了 37%，而女性 FI 减少了 26%，与 Qmax 减少相似。
与尿流率研究相比，PFS 期间排尿效率，以 Qmax 和 FI 评估，会降低。我们的数据首次记录了导尿对儿科排尿效率的影响。只有在通过尿流获得时，异常流速和升高的 PVR 才应用于指导患者管理。比较自由流与 PFS 研究的前瞻性验证将有助于描述尿道导管相对于膀胱病理、年龄、性别和使用的导管大小的相对影响。
