The present invention relates to a medical device for performing surgery in the body using a percutaneous dilatational procedure, one embodiment of which is a percutaneous dilatational tracheostomy (PDT) device having a dilator with a non-uniform surface profile that is optimized to the relevant anatomy in order to reduce, uniformly distribute, and ensure uniform, or constant temporal derivative of, dilatational force throughout dilation. This serves to reduce trauma to the patient, specifically producing a reduction of anterior tracheal wall compression, posterior wall laceration/perforation, and tracheal ring fracture that may subsequently lead to subglottic suprastomal stenosis.
