RESUMO
BACKGROUND: The Fatigue Rate Index (FRI) is a parameter in anorectal manometry (ARM) to assess sustained voluntary contraction, considering the squeeze pressure and fatigability of the external anal sphincter. It is used in adults to detect fecal incontinence even in patients who present normal squeeze pressures. The FRI in adult patients with functional constipation is similar to controls. OBJECTIVE: The aim of this study was to evaluate the feasibility and values of FRI in children in relation to the values previously established in adults and comparing children with functional constipation and retentive fecal incontinence to children without retentive fecal incontinence. METHODS: This retrospective study evaluated 105 ARM performed from Jan 2014 to Apr 2015. 42 patients were selected (were able to perform a voluntary contraction and had no co-morbidities other than functional constipation). 14 (33.3%) of those collaborated in sustaining contraction for 40 seconds (s), allowing the evaluation of the FRI. Patients with retentive fecal incontinence secondary to functional constipation (n=7, aged 6 to 13 years, six boys) were our interest group. Patients with functional constipation without fecal incontinence (n=7, aged 6 to 13 years, four boys) were considered a reference group. The ARM were performed with a radial eight-channel perfusion catheter (DynamedTM, São Paulo, Brazil) and the FRI was calculated (Proctomaster 6.4) in the first 20 s and overall 40 s of sustained voluntary contraction. RESULTS: 14 of the selected 42 collaborated in sustaining contraction for 40 s, allowing the evaluation of the FRI. In the first 20 s of contraction, the fecal incontinence group showed a significantly higher mean FRI (2.48±1.39 min) compared to the reference group (1.13±0.72 min, P=0.042), which was not observed in the 40 s interval due to less uniform contraction. The anal resting pressure was higher in the fecal incontinence group (76.83 mmHg) than in the reference group (54.13 mmHg), but the statistical study did not reach significance (P=0.051). CONCLUSION: The FRI is feasible in children. The mean FRI obtained in this study is lower than the reported in constipated adults. The mean FRI among children with functional constipation and retentive fecal incontinence is higher than among constipated children without retentive fecal incontinence.
Assuntos
Incontinência Fecal , Adulto , Brasil , Criança , Constipação Intestinal/diagnóstico , Fadiga , Humanos , Masculino , Manometria , Estudos RetrospectivosRESUMO
ABSTRACT Background: The Fatigue Rate Index (FRI) is a parameter in anorectal manometry (ARM) to assess sustained voluntary contraction, considering the squeeze pressure and fatigability of the external anal sphincter. It is used in adults to detect fecal incontinence even in patients who present normal squeeze pressures. The FRI in adult patients with functional constipation is similar to controls. Objective: The aim of this study was to evaluate the feasibility and values of FRI in children in relation to the values previously established in adults and comparing children with functional constipation and retentive fecal incontinence to children without retentive fecal incontinence. Methods: This retrospective study evaluated 105 ARM performed from Jan 2014 to Apr 2015. 42 patients were selected (were able to perform a voluntary contraction and had no co-morbidities other than functional constipation). 14 (33.3%) of those collaborated in sustaining contraction for 40 seconds (s), allowing the evaluation of the FRI. Patients with retentive fecal incontinence secondary to functional constipation (n=7, aged 6 to 13 years, six boys) were our interest group. Patients with functional constipation without fecal incontinence (n=7, aged 6 to 13 years, four boys) were considered a reference group. The ARM were performed with a radial eight-channel perfusion catheter (DynamedTM, São Paulo, Brazil) and the FRI was calculated (Proctomaster 6.4) in the first 20 s and overall 40 s of sustained voluntary contraction. Results: 14 of the selected 42 collaborated in sustaining contraction for 40 s, allowing the evaluation of the FRI. In the first 20 s of contraction, the fecal incontinence group showed a significantly higher mean FRI (2.48±1.39 min) compared to the reference group (1.13±0.72 min, P=0.042), which was not observed in the 40 s interval due to less uniform contraction. The anal resting pressure was higher in the fecal incontinence group (76.83 mmHg) than in the reference group (54.13 mmHg), but the statistical study did not reach significance (P=0.051). Conclusion: The FRI is feasible in children. The mean FRI obtained in this study is lower than the reported in constipated adults. The mean FRI among children with functional constipation and retentive fecal incontinence is higher than among constipated children without retentive fecal incontinence.
RESUMO Contexto O índice de Taxa de Fadiga (ITF) é um parâmetro na manometria anorretal (MAR) que é utilizado para avaliar a contração voluntária sustentada, considerando a pressão máxima de contração e a fatigabilidade do esfíncter anal externo. Este parâmetro é utilizado em adultos para diagnóstico da incontinência fecal mesmo entre paciente que apresentem pressões máximas de contração normais. O ITF em pacientes adultos com constipação é similar a controles. Objetivo: Avaliar a factibilidade e os valores do ITF em crianças com constipação e incontinência fecal por retenção em relação aos valores previamente estabelecidos para adultos, e comparar os dados das crianças com constipação intestinal funcional com e sem incontinência fecal por retenção. Métodos Este estudo retrospectivo avaliou 105 MAR realizadas de janeiro de 2014 a abril de 2015. 42 pacientes foram selecionados (foram capazes de realizar uma contração voluntária e não apresentavam outras comorbidades além da constipação). 14 destes pacientes cooperaram em manter a contração voluntária por 40 segundos, permitindo a avaliação do ITF. Pacientes com incontinência fecal por retenção secundária a constipação (n=7, 6 a 13 anos, seis meninos) constituíram nosso grupo de interesse. Pacientes com constipação funcional sem incontinência fecal por retenção. (n=7, 6 a 13 anos, quatro meninos) constituíram o grupo de referência. As MAR foram realizadas com cateter de perfusão de oito canais radiais (DynamedTM, São Paulo, Brazil) e o ITF foi calculado (Proctomaster 6.4) nos primeiros 20 segundos e também nos 40 segundos totais da contração voluntária sustentada. Resultados: Dos 42 pacientes selecionados, 14 (33%) colaboraram mantendo o platô de contração uniforme durante 40 segundos, permitindo a avaliação do ITF nos primeiros 20 segundos de contração, o grupo com incontinência fecal apresentou uma média de ITF significativamente mais alta (2,48±1,39 min) em comparação ao grupo de referência (1,13±0,72 min, P=0,042), o que não foi observado no intervalo de 40 segundos devido a contração menos uniforme. A pressão anal de repouso foi mais elevada no grupo com incontinência fecal (76,83 mmHg) do que no grupo de referência (54,13 mmHg), porém o estudo estatístico não atingiu significância (P=0,051). Conclusão: O ITF é factível em crianças. A média do ITF obtida neste estudo é mais baixa do que o reportado em adultos constipados (2,8 min). A média do ITF entre crianças constipadas com incontinência fecal por retenção fui superior ao do que observado em crianças constipadas sem incontinência fecal retentiva.
