After open-heart and other major surgery, prolonged endotracheal intubation for postoperative respiratory assistance may cause irritation and damage to the mucous membranes of the airways. The communication by Guess and Stetson on page 580 of this issue draws attention to one possible cause, if polyvinyl chloride (PVC) plastic tubes are used. Though unnoticed in medical journals, this problem has concerned scientists for some years. It is appropriate, therefore, to alert the medical profession to several difficulties which have arisen with this equipment.
All PVC used for endotracheal tubes contains stabilizer compounds which, during use, tend to leach out of the plastic. Guess and Stetson show that some stabilizers may cause serious irritation when the plastic remains in contact with the tissues for several days. When tubes were used solely for anesthesia, past freedom from complaints may be explained by the shorter period of contact. In the absence of national standards