Reproducibility of Intra-Abdominal Pressure Measured During Physical Activities Via a Wireless Vaginal Transducer

Abstract

Aims In the urodynamics laboratory setting, a wireless pressure transducer, developed to facilitate research exploring intra-abdominal pressure (IAP) and pelvic floor disorders, was highly accurate. We aimed to study reproducibility of IAP measured using this transducer in women during activities performed in an exercise science laboratory. Methods Fifty seven women (mean ± SD: age 30.4 ±9.3 years; body mass index=22.4 ± 2.68 kg/m2) completed two standardized activity sessions using the same transducer at least three days apart. Pressure data for 31 activities were transmitted wirelessly to a base station and analyzed for mean net maximal IAP, area under the curve (AUC) and first moment of the area (FMA.) Activities included typical exercises, lifting 13.6 to 18.2 kg, and simulated household tasks. Analysis for test-retest reliability included Bland-Altman plots with absolute limits of agreement (ALOA), Wilcoxon signed rank tests to assess significant differences between sessions, intraclass correlations, and kappa statistics to assess inter-session agreement in highest vs. other quintiles of maximal IAP. Results Few activities exhibited significant differences between sessions in maximal IAP, or in AUC and FMA values. For 13 activities, the agreement between repeat measures of maximal IAP was better than ± 10 cm H20; for 20 activities, better than ± 15 cm H20. ALOA increased with mean IAP. The highest quintile of IAP demonstrated fair/substantial agreement between sessions in 25 of 30 activities. Conclusion Reproducibility of IAP depends on the activity undertaken. Interventions geared towards lowering IAP should account for this, and maximize efforts to improve IAP reproducibility.

Effects of walking speeds and carrying techniques on intra-abdominal pressure in women

“…In previous work, we found that activities with higher maximal IAP tended to have greater variability between two sessions, though very few activities demonstrated a statistically significant difference in mean maximal IAP between sessions. [20] However, in two activities similar to that performed for the current study, the absolute limits of agreement for net mean maximal IAP were 5.6 cm H 2 O for walking 4.8 km/hr at 0% grade and 11.5 cm H 2 O for walking 4.3 km/hr at 0% grade carrying an 11.4 kg weight. If reproducibility is similar between conducting these activities on a treadmill versus a track (as in the current study), the differences seen between activities overcome the inherent test-retest variability of the measures.…”

Intra‐abdominal and perineal pressures during abdominal exercises: A cross sectional study in postpartum women

“…10 In another study of 51 predominantly nulliparous women, Curl-up maximal IAP mean value was 22.1 cm H 2 O while it was 100.2 cm H 2 O during cough. 13 The IAP increase during Curl-up appears thus to be much lower than during coughing. In addition, an electromyographic activation of 44% of maximal voluntary contraction (MVC) of the pelvic floor muscles during Curl-up was measured by Neumann et al 15 in four nulliparous women.…”

“…[6][7][8] IAP during exercises is most often measured using vaginal or rectal sensor. [9][10][11][12] Coughing, Valsalva maneuver, and jumping have been described as the most hyperpressive exercises 9,13 and are avoided as much as possible in post-partum.…”

Development of anatomically based customizable three-dimensional finite-element model of pelvic floor support system: POP-SIM1.0

“…The abdominal pressure loading was placed perpendicular to the AVW. In all simulations in this study, the Valsalva (increasing in abdominal pressure loading) was simulated using 20 increments in pressure from 0 to 100 cmH 2 O, with the maximum Valsalva pressure close to the average laying Valsalva pressure measured using a vagina pressure sensor [37]. To reduce computation time, the simulated Valsalva process was scaled to 1 s.…”