A device for providing access through a body wall of a patient to a target site includes a hollow tube having a first large diameter segment and a second small diameter segment. A first distally tapered portion joins the first segment and the second segment, and a second distally tapered portion is distal of the second segment. A first lumen extends through the tube, and a second lumen extends from a proximal portion of the tube to the second segment. A needle received in the first lumen is deployable for piercing the body wall. A port is provided along the second segment in communication with the second lumen, and a balloon is disposed along the second segment at the port. The balloon is inflatable to a diameter at least as large as the first segment diameter for dilating an opening in the body wall.
