Systematic review and meta-analysis of anal motor and rectal sensory dysfunction in male and female patients undergoing anorectal manometry for symptoms of faecal incontinence.

AIM: Manometry is the best established technique to assess anorectal function in faecal incontinence. By systematic review, pooled prevalences of anal hypotonia/hypocontractility and rectal hypersensitivity/hyposensitivity in male and female patients were determined in controlled studies using anorectal manometry. METHODS: Searches of MEDLINE and Embase were completed. Screening, data extraction and bias assessment were performed by two reviewers. Meta-analysis was performed based on a random effects model with heterogeneity evaluated by I2 . RESULTS: Of 2116 identified records, only 13 studies (2981 faecal incontinence patients; 1028 controls) met the inclusion criteria. Anal tone was evaluated in 10 studies and contractility in 11; rectal sensitivity in five. Only three studies had low risk of bias. Pooled prevalence of anal hypotonia was 44% (95% CI 32-56, I2 = 96.35%) in women and 27% (95% CI 14-40, I2 = 94.12%) in men. The pooled prevalence of anal hypocontractility was 69% (95% CI 57-81; I2 = 98.17%) in women and 36% (95% CI 18-53; I2 = 96.77%) in men. Pooled prevalence of rectal hypersensitivity was 10% (95% CI 4-15; I2 = 80.09%) in women and 4% (95% CI 1-7; I2 = 51.25%) in men, whereas hyposensitivity had a pooled prevalence of 7% (95% CI 5-9; I2 = 0.00%) in women compared to 19% (95% CI 15-23; I2 = 0.00%) in men. CONCLUSIONS: The number of appropriately controlled studies of anorectal manometry is small with fewer still at low risk of bias. Results were subject to gender differences, wide confidence intervals and high heterogeneity indicating the need for international collective effort to harmonize practice and reporting to improve certainty of diagnosis.

Deferred consent in emergency obstetric research: findings from qualitative interviews with women and recruiters in the ACROBAT pilot trial for severe postpartum haemorrhage.

OBJECTIVE: The ACROBAT pilot trial of early cryoprecipitate for severe postpartum haemorrhage used deferred consent procedures. Pretrial discussions with a patient and public involvement group found mixed views towards deferred consent. This study aimed to build an understanding of how the deferred consent procedures worked in practice, to inform plans for a full-scale trial. SETTING: Qualitative interview study within a cluster-randomised pilot trial, involving four London maternity services. PARTICIPANTS: Individual interviews were conducted postnatally with 10 women who had received blood transfusion for severe postpartum haemorrhage and had consented to the trial. We also interviewed four 'recruiters'-two research midwives and two clinical trials practitioners who conducted trial recruitment. RESULTS: Consent procedures in the ACROBAT pilot trial were generally acceptable and the intervention was viewed as low risk, but most women did not remember much about the consent conversation. As per trial protocol, recruiters sought to consent women before hospital discharge, but this time pressure had to be balanced against the need to ensure women were not approached when distressed or very unwell. Extra efforts had to be made to communicate trial information to women due to the exhaustion of their recovery and competing demands for their attention. Participant information was further complicated by explanations about the cluster design and change in transfusion process, even though the consent sought was for access to medical data. CONCLUSION: Our findings indicate that deferred consent procedures raise similar concerns as taking consent when emergency obstetric research is occurring-that is, the risk that participants may conflate research with clinical care, and that their ability to process trial information may be impacted by the stressful nature of recovery and newborn care. A future trial may support more meaningful informed consent by extending the window of consent discussion and ensuring trial information is minimal and easy to understand. TRIAL REGISTRATION NUMBER: ISRCTN12146519.

Systematic evaluation of cough-anorectal pressure responses in health and in fecal incontinence: A high-resolution anorectal manometry study.

BACKGROUND: Anorectal manometry is the most commonly performed test of anorectal function. The cough-anorectal response is frequently assessed as part of a routine manometric investigation but has not previously been the subject of detailed analysis. This study systematically examined anorectal pressure responses to cough in health and evaluated the impact of parity and symptoms of fecal incontinence (FI) on measurements. METHODS: High-resolution anorectal manometry (HR-ARM) traces from nulliparous (n = 25) and parous (n = 25) healthy volunteers (HV: aged 41, range 18-64), and 57 parous patients with FI (age 47, range 28-72) were retrospectively reviewed. Cough-anorectal pressure responses were analyzed between groups by qualitative and quantitative approaches. KEY RESULTS: In health, traditional anal pressure measurements ("rest" and "squeeze") were similar between nulliparous and parous women. In contrast, incremental anal-rectal pressure difference during cough significantly differed: nulliparous 42 mm Hg (95% CI: 21-64) vs. parous 6 mm Hg (-14-25), P < 0.036). This measure also differed significantly between nulliparous HVs and patients with FI (-2 mm Hg (95% CI: -15-12), P < 0.001), but not between parous HVs and FI. Qualitatively, a color-contour trace resembling a "spear" in the upper anal canal was observed uniquely in FI. Of 25 patients with normal anal function by traditional measures, cough parameters were abnormal in 52%. CONCLUSIONS AND INFERENCES: Novel HR-ARM measures during coughing revealed differences in anal function between nulliparous and parous HV, and patients with FI, which were not detected by traditional measures. Cough-anorectal measurements may improve manometric yield, though clinical utility would require assessment by longitudinal studies.

Functional anal canal length measurement using high-resolution anorectal manometry to investigate anal sphincter dysfunction in patients with fecal incontinence or constipation.

BACKGROUND: Using high-resolution anorectal manometry, we aimed to evaluate the: (a) optimal threshold to measure functional anal canal length (FACL) with intra- and inter-observer variability; (b) relationship between abnormal FACL and other phenotypic findings; and (c) utility of FACL measurement to discriminate between healthy volunteers (HV) and patients with fecal incontinence (FI) or chronic constipation (CC). METHODS: Consecutive patients referred for investigation of FI or CC in isolation were included. FACL was calculated at 5, 10, 20, 30, and 50 mm Hg above rectal pressure. 5th-95th percentile in HV defined limits of normality. KEY RESULTS: FACL was analyzed in 192 patients with FI (154 females), 204 patients with CC (175 females), and 134 HV (101 females). The optimal threshold for measurement of FACL was 20 mm Hg. Using this threshold, observer reproducibility was very high (ICC 0.99, P < 0.0001). FACL was shorter in females with FI and longer in females with CC compared to HV (2.3 vs 2.9 cm; and 3.4 cm vs 2.9 cm; both P < 0.0001). Twenty percent of females and 13% males with FI had a short FACL, associated with older age, anal hypotonia or hypocontractility, and a atrophic internal anal sphincter. However, abnormal FACL in isolation was only found in 1/190 FI (0.5%) and 2/201 CC (1%) patients; all other patients had other abnormal manometric findings. CONCLUSIONS AND INFERENCES: Considering overlap with other routinely evaluated manometric parameters, FACL measurement does not provide additional information in the diagnostic assessment of FI or CC.