1. Resident, Department of Anesthesia, University Hospitals, Iowa City, Iowa. Present address: Department of Anesthesia, University Hospital, Madison, Wisconsin
2. Graduate Student, Department of Otolaryngology, University Hospitals, Iowa City, Iowa. Present address: Hearing and Speech Division, Children's Hospital Medical Center, Boston, Massachusetts
3. Professor and Chairman, Department of Anesthesia, University Hospitals, Iowa City, Iowa