I appreciate the honor of being invited to give the lecture in honor of Dr. Carl A. Hedblom. The subject I have chosen is quite appropriate, since Dr. Hedblom was one of the pioneers in the development of this field of surgery. He was endowed with a spirit of investigation and a determination to overcome obstacles in solving the problem at hand. Almost unlimited courage was formerly needed to face the tremendous risks involved in certain new operations which today have a low mortality and seem commonplace. Much is owed to these early pioneers, for without their continued effort the development of thoracic surgery would have been considerably delayed.
Dr. Hedblom made many contributions in this field of surgery and was an outstanding teacher and an inspiration to his associates. It is unfortunate that he could not see the accomplishments of more recent years.
In order better to appreciate much