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Prevalence of rectoanal inhibitory reflex in chagasic megacolon
Simone Cavenaghi1, Otaviano Cardoso da Silva Felicio, Luis Sergio Ronchi
1Service of Physiotherapy, Department of Neurological Sciences, Hospital de Base, São José do Rio Preto Medical School, São José do Rio Preto, SP, Brazil. sicavenaghi@ig.com.br
Background:
Rectoanal inhibitory reflex is not always evident in patients with chagasic megacolon. This may be due to insufficient volumes of air used during insufflation for the manometric examination.
Aims:
To identify the volume of air necessary to induce rectoanal inhibitory reflex in patients with chagasic megacolon and to observe its prevalence in these individuals.
Methods:
Rectoanal inhibitory reflex in 39 patient with chagasic megacolon was studied by means of anorectal manometry using the balloon method. The balloon was insufflated using sequential volumes up to 300 mL to induce reflex.
Results:
Rectoanal inhibitory reflex was identified in 43.6% of the patients using a mean volume of 196 mL of insufflated air (standard error = 13.5).
Conclusion:
Rectoanal inhibitory reflex can be induced in patients with chagasic megacolon when greater volumes of air are used.
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