Dr. Guisto is originally from Reno, Nevada where he grew up enjoying the outdoor opportunities of the northern Nevada, Lake Tahoe and Sierra Mountain areas. He left Reno for his undergraduate education at Stanford University, earning a Bachelor of Arts degree in Classics and enjoying the breadth of opportunity there including such things as a summer at Hopkins Marine Biology Research Station in Monterey Bay. He then returned to Reno for Medical School at U. of Nevada Reno. After achieving his MD degree there, he went to Salt Lake City for a General Surgery internship at the University of Utah. He then moved to Tucson for the Emergency Medicine residency at the University of Arizona, graduating as a chief resident.

After residency he took a summer job as a Locum Tenens physician in the ED in Jackson Wyoming just for the fun of it, then with a couple of friends bicycled England and France for a month for the same reason. On returning to Tucson he practiced in various private sector Emergency departments in the area. He began filling in shifts at the University Medical Center ED and then was offered full time employment there and has been Emergency Medicine faculty at the University of Arizona ever since.

Professional interests include ED operations and Wilderness Medicine. Free time interests include cycling, hiking, backpacking, fly fishing and learning various crafts.