[Does the use of fentanyl make Vater's ampulla cannulation difficult? A prospective and comparative study]

A Güitrón-Cantú1, R Adalid-Martínez, J A Gutiérrez-Bermúdez

  • 1Departamento de Endoscopia Digestiva, Hospital de Especialidades UMAE N° 71 Instituto Mexicano del Seguro Social, Torreón, Coahuila, México. aguitron@prodigy.net.mx

Abstract