Duration taken for the anal sphincter pressures to stabilize prior to anorectal manometry

Abstract

ObjectivesAnorectal manometry (ARM) is an integral part of evaluating the anal sphincter function. The current recommendation of waiting for 5 min (lead-in-time) prior to beginning the recording has no evidence. A prolonged procedure may reduce patient compliance.ResultsWe analyzed data from 100 consecutive patients who underwent 3-dimensional ARM at a single center. Their pressure studies were analyzed in consecutive 10-s segments, beginning from the time of insertion of the probe into the anal canal. We defined stabilization of the pressure as the absence of a pressure difference among two consecutive 10-s segments. The study population had 31 males. Their mean age was 33.0 years (SD-14.4). The mean time for the pressure to stabilize was 84.2 s (SD-29.5), range 17.2–203.7 s, 95th percentile 136.2 s. Eleven and one participant(s) took longer than 120 and 150 s for the pressure to stabilize, respectively. There was no correlation of sex (Mann–Whitney U test, p = 0.89) and the time to pressure stabilization. Age and the time to stabilize (Spearman rho − 0.246, p = 0.017) showed a weak negative correlation. A lead-in-time of 5 min, as recommended by present guidelines may be unnecessary. Waiting for 150 s/2½ min may be sufficient and will minimize the procedure duration.

Optimizing techniques for measuring anal resting and squeeze pressures with high‐resolution manometry

“…Taken together with other recent studies, these findings provide the basis for streamlining the anorectal HRM procedure. Because anal pressures stabilized within 150 s, typically in 90 s, after the catheter was inserted, 32 the equilibration period before pressure measurements commence can perhaps be shortened to less than the 3 min recommended by the IAPWG 8 . Among FI patients, the London group observed that resting pressures can be evaluated over 30 instead of 60 s recommended by the IAPWG protocol 8 and that 2 rather than 3 squeeze maneuvers are sufficient 22 .…”

“…Taken together with other recent studies, these findings provide the basis for streamlining the anorectal HRM procedure. Because anal pressures stabilized within 150 s, typically in 90 s, after the catheter was inserted, 32 the equilibration period before pressure measurements commence can perhaps be shortened to less than TA B L E 5 Utility of anorectal variables for discriminating between healthy women and fecal incontinence and that 2 rather than 3 squeeze maneuvers are sufficient. 22 Our findings suggest that anal resting and squeeze pressures should each be measured for 20 s. As suggested above, arguably, a longer squeeze maneuver may be more useful for distinguishing between healthy and FI women.…”

Review of the indications, methods, and clinical utility of anorectal manometry and the rectal balloon expulsion test

“…Voluntary contraction of the anal sphincter may increase anal pressure upon insertion of the catheter. On average, it takes less than 90 s for pressures to equilibrate; 150 s is sufficient, 32 and is less than the 3 min recommended by the International Anorectal Physiology Working Group (IAPWG) 11 …”

Anorectal Manometry in Children

“…The probe should then be held there for at least 90 seconds for the anorectal area to settle after the insertion and to adapt to the presence of the probe before obtaining data. Some authors suggest taping the exteriorized portion probe to the buttocks (11), which may be problematic for children who are anxious or move as it can displace the catheter in less cooperative children, while others suggest to wait for longer times before testing (37).…”