An innovative, non-invasive sensation meter allows for a more comprehensive understanding of bladder sensation events: A prospective study in participants with normal bladder function

Abstract

Aims: There is currently no standardized method of characterizing changes in bladder sensation during bladder filling outside of the urodynamics laboratory. The purpose of this investigation was to characterize real-time bladder sensation events using a sensation meter during oral hydration in individuals with normal bladder function.

Methods: Participants enrolled in an accelerated hydration study drank 2 L Gatorade-G2® and utilized a sensation meter to record real-time bladder sensation (0-100%), verbal sensory thresholds, and sensation descriptors of "tense," "pressure," "tingling," "painful," and "other" for two consecutive fill-void cycles.

Results: Data from 21 participants (12 females/9 males) were obtained and demonstrated an average of 8-9 sensation events (significant changes in sensation) per fill with no differences in the total number of sensation events and volume between sensation events (fill 1 vs fill 2). An increased number of sensation events occurred at higher capacity quartiles. Event descriptors of "pressure" and "tingling" were the most commonly chosen descriptors in both fills.

Conclusions: The innovative sensation meter includes the sensation event descriptors of "tense," "tingling," "pressure," and "painful," to enable a more comprehensive understanding of bladder sensation as well as real-time identification, quantification, and characterization of sensation events. The study demonstrates 8-9 events per fill, acceleration of sensation during filling, and unique sensation event descriptor patterns. This technology may be helpful in the identification of novel sensation patterns associated with overactive bladder (OAB) and aging.

Keywords: diuresis/physiology; sensation/physiology; urinary bladder/physiology.

FIGURE 1

A, Screenshot of sensation meter with associated Start and Stop buttons, slider bar interface (bottom), and verbal sensation threshold (VST) selection (right). B, Screenshot of sensation meter after change in sensation from example participant data (see Figure 1D). At 53.7 min (3222 s as measured by sensation meter), the participant perceived bladder sensation at 71% (bottom), selected first desire from the VST selection (right), and marked pressure and tingling from the descriptors selection (left). C, Same participant’s sensation meter data plotted as % sensation versus time, with associated VSTs marked accordingly. D, Chart corresponding to Figures 1B and 1C shows that participant perceived seven sensation events (Column 1) at the times provided (Column 2). The corresponding % sensation (Column 3), estimated filling volume (Column 4), VSTs: first sensation (FS), first desire (FD), and strong desire (SD) (Column 5), and sensation descriptors (Column 6) are also recorded

FIGURE 2

Box plots of sensation event changes between fills. Each dot represents one participant, (total: n = 21) with fill 1 (purple) versus fill 2 (orange). A, Number of sensation events. B, Average duration between sensation events, P < 0.0001 between fill 1 and fill 2. C, Average volume per sensation event

FIG. 3

Changes in sensation events throughout the course of filling. Number of sensation events per capacity quartile (A, fill 1 and B, fill 2). Each dot represents one participant (total: n = 21). Capacity quartiles are marked pink (0–25), green (>25–50), blue (>50–75), and orange (>75–100). Both fills demonstrate a significant difference in the number of sensation events between the first and third (A, P = 0.013 and B,P = 0.003) and the first and final (A, P < 0.0001 and B, P < 0.0001) capacity quartiles

FIG. 4

Descriptors and the % sensation at which they were selected (A, fill 1 and B, fill 2, n = 18). Each mark (black triangle) represents one event where a specific descriptor was selected. Descriptors are classified as pink (tense), green (pressure), blue (tingling), and orange (painful). Both fills had a significant difference in the frequency of descriptor selection between tense and pressure (A, P = 0.0019 and B, P = 0.0055) and tense and tingling (A, P < 0.0001 and B, P = 0.0043)