RESUMO
BACKGROUND/AIMS: External anal sphincter (EAS) plays an important role in fecal and gas voluntary continence. Like every muscle, it can be affected by repeated efforts due to fatigability (physiological response) and/or fatigue (pathological response). No standardized fatiguing protocol and measure method to assess EAS fatigability has existed. The aim is to test a simple, standardized protocol for fatiguing and measuring EAS fatigability and fatigue to understand better the part of EAS fatigability in the pathophysiology of fecal incontinence. METHODS: Patients with anorectal disorders evaluated with anorectal manometry were included. They had to perform 10 repetitions of maximum voluntary contraction (MVC) of 20 seconds. Measurement was made with an anorectal manometry catheter and a surface recording electromyography (EMG). The primary outcome was the difference in EMG root mean square between the first and the last MVC. Secondary outcomes were differences in other EMG and manometry parameters between the first and the last MVC. Difficulties and adverse effects were recorded. RESULTS: Nineteen patients underwent the fatiguing protocol. All patients completed the entire protocol and no complications were found. No difficulty was declared by the examiner. A significant decrease in root mean square was found between the first and last MVC (0.01020 ± 0.00834 mV vs 0.00661 ± 0.00587 mV; P = 0.002), in maximum anal pressure area under the curve of continuous recordings of anal pressure and mean and total EMG power (P < 0.05). CONCLUSIONS: This protocol is simple and minimally invasive to measure EAS fatigue and fatigability. We highlighted a fatigue of EAS in many patients with anorectal disorders.
RESUMO
AIMS: The primary aim of this study was to assess the relationship between a strong desire to void (SDV) and rectal sensory function in patients with multiple sclerosis (PwMS) and anorectal disorders. The secondary aim was to identify clinical, urodynamic or manometric factors associated with greater rectal sensory function impairment in this population. METHODS: Thirty PwMS (mean age 49.2 ± 10.9 years) with anorectal disorders (constipation and/or fecal incontinence) participated in this observational study. Rectal sensory parameters during anorectal manometry were recorded at a strong desire to void and after urination (PV, post-void). The primary outcome was the desire to defecate volume. Secondary outcomes were first perception and maximum tolerated threshold volumes, presence and modulation of recto-anal inhibitory reflex. RESULTS: The mean desire to defecate volume was 125 ± 59 mL at SDV and 104 ± 64 mL at PV (P < .001). The mean maximum tolerated volume was 167 ± 61 mL at SDV vs 141 ± 64 mL after urination (P = .01). The other parameters were not different between SVD and PV conditions. No predictive factors for greater impairment of rectal sensory function were identified. CONCLUSION: This study suggests a relationship between bladder sensation and thus bladder capacity, and rectal sensory function in PwMS and with anorectal disorders.
