Hypothesis / aims of study
Indwelling suprapubic catheters (SPCs) are used in patients with poor bladder emptying, often instead of indwelling urethral catheters and where urethral clean intermittent catheterisation (CIC) has proved challenging due to anatomy, pain or dexterity. Disadvantages include blockages, recurrent infections and cosmetic appearance. Catheter-induced bladder pain, often due to irritation of the Foley catheter on the bladder mucosa, can be challenging. Despite these recognised complications, the patient satisfaction rate compared to long-term urethral catheterisation remained high, with most patients (89%) showing a preference for SPC over long-term urethral catheterisation.
The MIC-KEY low-profile gastrostomy feeding tube is approved for gastric feeding. It was designed to allow patients greater movement, is difficult to dislodge, and is easy to conceal under clothing. Although designed as a gastrostomy, the attributes of the MIC-KEY button are potentially beneficial for urinary drainage, and has been identified as a safe alternative in the short to medium-term in children for bladder drainage . We present our experience in adults.
Study design, materials and methods
Prospective data was collected on patients with indwelling SPC that were converted to MIC-KEY buttons, or cystoscopic guided de novo insertion between November 2014-February 2019. Changes were performed dependent on patient’s personalised management, typically every 3 months, under local or general anaesthetic. Validated catheter-related quality of life (C-IQoL) data was collected. The questionnaire consists of three sub-scores evaluating catheter management (10 items), interpersonal (7 items) and psychosocial (5 items) impact (Table 1); a five point Likert-type scale was used, with strongly agree = 1; agree = 2; neutral = 3; disagree = 4; and strongly disagree = 5. A higher score reflects a less severe symptom profile.
16 patients (14 female, two male) had conversion or attempted conversion; one patient had an open insertion. One patient had an initial conversion under paediatric care, and continued changes in adult services. The mean age was 44.2 years (range 13-73 years). 2 patients had attempted conversion but were abandoned peri-operatively due to sizing issues and insertion difficulties respectively. There were no significant adverse events, with Grade II complications occurring in 3 patients due to post-operative UTI.
3 patients were subsequently converted back to SPC; due to button sizing (18 days), leaking (3 months), and recurrent infection (13 months). The remaining 11 patients have remained well with continued drainage via MIC-KEY button; mean duration since conversion was 34.2 months (range: 5-105 months). 4 of those 11 patients had recurrent UTIs prior to MIC-KEY button conversion; 3 of 4 have reported an improvement or resolution of their UTIs. C-IQoL score improved after insertion, from 50.0 to 75.4.
Interpretation of results
Our prospective pilot study demonstrates feasibility and safety of the MIC-KEY button as an alternative form of suprapubic bladder drainage in adult patients. In the 11 patients who have had short to medium-term drainage with the MIC-KEY button, it has proven to be a well tolerated alternative to SPC with improvement in QOL. Improvements were seen for all three C-IQoL domains at three months follow-up; this reached significance for the management (p=0.019) and psychosocial (p=0.001) subscores. Sizing of the MIC-KEY button was identified as an issue in the study, with a total of three patients returning to suprapubic catheters due to issues with button sizing either peri-operatively or early post-operatively.