An endoscopic device for use at a site within a body includes an inner portion and a sheath surrounding the inner portion. The inner portion defines an operative channel and an optical channel. The operative channel provides a path for fluid to or from the body site. The sheath defines a pressure-sensing channel and a fluid channel that provides a path for fluid to or from the body site. The pressure-sensing channel and the fluid channel are defined between the sheath and the inner portion. The pressure-sensing channel is configured to couple to a pressure sensor to sense pressure at the body site.