Intermittent catheterization (IC), considered the gold standard for bladder management for individuals with spinal cord injury (SCI) with sufficient dexterity, is usually performed using hydrophilic (HPC) or non-hydrophilic (non-HPC) catheters. Considering the lack of evidence on whether HPCs or non-HPCs are more efficient with respect to time required for bladder management, our aim was to compare both types of catheters regarding time needed to perform IC and user satisfaction.

This pilot cross-over randomized controlled trial (RCT) was approved by the local ethics ethics committee, while conforming to the Declaration of Helsinki and adhering to the CONSORT guidelines. 
The objective of this study is to compare both catheters regarding their time requirement for IC and participant satisfaction. The inclusion criteria were as follows: female or male, age 18 years or older, presenting with chronic (at least 1-year post-injury) SCI, fluent in English, hand function sufficient to perform IC, not being pregnant, and without history of urinary diversion. Sixty-five individuals were screened between December 2018 and April 2019 according to the inclusion and exclusion criteria from which 21 individuals were invited for a baseline visit. One eligible individual withdrew due to personal reasons. Our target number of participants (n = 20) for this pilot cross-over RCT is in line with general recommendations from the literature. [1-3].
After enrollment into the study, 20 participants were randomized into two groups (i.e., starting with an HPC or non-HPC, allocation ratio 1:1) using a random sequence generator. In May and June 2019, participants underwent two cross-over assessment within 10 days. Participants were followed up 5 to 10 days later via phone regarding potential adverse events (AEs). All catheters were provided by Coloplast A/S (Humlebæk, Denmark), i.e., HPC (SpeediCath®) and non-HPC (Self-Cath®). For non-HPC, lubrication jelly was provided.
The two primary outcome objectives of this study were the time needed to perform IC and user satisfaction (between HPC and non-HPC). The secondary outcome objectives were time needed to perform IC with respect to the participants’ level of injury and catheter use in daily life.
We measured time taken to perform IC using a 13 step pre-determined IC protocol (e.g., enter bathroom, wash hands, transfer to toilet, etc.). At each assessment visit, participants performed a guided test run to familiarize themselves with the protocol. Then, each step was recorded separately. At the end of each assessment, participants completed a questionnaire regarding their catheter satisfaction using a Likert scale (i.e., strongly agree = 5, strongly disagree = 1). The primary and secondary outcome measures were time (i.e., for each step and in total) to perform IC and participant satisfaction were compared between catheters.
Data are presented as raw values and percentages. Results are presented as median with interquartile range (IQR). In addition, range (i.e., min - max) is provided for age and time post injury. Non-parametric statistics were conducted, i.e., the Wilcoxon signed-rank test for primary and secondary outcomes (i.e., all variables except for the preferred catheter question which was tested with the Wilcoxon rank-sum test). All statistical tests were two-sided, and p < 0.05 was considered statistically significant.

Twenty participants (five females) with a median age of 45 years (36 - 53, range 26 - 65) and median time post injury of 14 years (10 - 26, range 3 - 46) completed the study. The majority were daily non-HPCs (75%, 15/20) users. One participant had a symptomatic UTI six days after the second assessment and was treated with antibiotics appropriately.
Participants using HPCs spent less time to prepare a catheter [15 s (10-20) vs. 41 (20-69), p=0.002] and overall to perform IC [283 s (242-352) vs. 373 (249-441), p=0.01] compared to non-HPCs. Moreover, HPC use was associated with significantly higher scores for “easiness to prepare” [5 (4 - 5) vs. 4 (2 - 4), p=0.047] and “did not feel burning” [5 (4 - 5) vs. 4 (3 - 5), p=0.042] compared to non-HPC.
For tetraplegic participants (9/20), total time taken to execute all 13 steps [300 s (249 - 352) vs. 421 (398 - 515), p=0.139] was shorter when using a HPC compared to a non-HPC but did not yield statistical significance. For paraplegic participants (11/20), total time overall was significantly shorter when using HPC compared to a non-HPC [272 s (210 - 353) vs. 296 (225 - 433), p=0.041].
For daily HPC users (5/20), total time overall [249 s (235 - 300) vs. 421 (241 - 491), p=0.08] was shorter when using a HPC compared to a non-HPC but did not yield statistical significance. For daily non-HPC users (15/20), total time overall was significantly shorter with HPC compared to non-HPC [285 s (253 - 353) vs. 348 (257 - 433), p=0.047]. 
For participants with either tetraplegia [16 (11-20) vs. 67 (46-81), p=0.038] and paraplegia [15 (9-24) vs. 21 (14-45), p=0.023] as well as for HPC [15 (11-17) vs. 46 (38-67), p=0.043] or non-HPC [16 (10-24) vs. 36 (16-78), p=0.021] users, only step ‘prepare catheter’ was significantly shorter when using HPC compared to non-HPC.

This pilot cross-over RCT provides evidence for a substantial IC time requirement for individuals with SCI, independent of the catheter type, with potential negative implications on levels of intra- and interpersonal stress, overall burden of SCI, workforce opportunities and IC compliance. The significance of reducing the time needed for IC while protecting the lower urinary tract makes it imperative that IC is performed efficiently which, in the context of this study, points to the merits of HPCs.

Preparation and usage of HPCs for IC is easier and faster compared to non-HPCs. IC can be a significant temporal burden for SCI individuals.

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