The paper by Doctors Vidyasagar and Chernick on the achievement of continuous positive transpulmonary pressure using continuous negative chest wall pressure contains a suggestion for modification of the Air-Shields Isolette-Respirator to permit its use in this fashion. They suggest the insertion of a switch into the electrical circuit to activate the solenoid valve and thereby permit continuous evacuation of air from the body compartment. While this modification is effective, it is not necessary to do so in order to achieve continuous negative pressure (CNP).