Pulmonary suffusion is a minimally invasive technique designed to deliver a high dose of a chemical substance (like chemotherapy) to tumors or other diseases within the chest. The concept is not new and researchers at Roswell Park attempted this in 1981 by using catheters to drip chemotherapy into the blood vessel coming off the heart into the lung. Unfortunately, this was not able to concentrate the drug so more invasive ideas like using a variation of the heart-lung machine to bypass the normal lung circulation were used. However, this required the use of large incisions and large tubes into thin blood vessels that was risky and invasive.
A simpler method was devised by Dr. Demmy and colleagues to use small incisions and snare the veins that deliver the blood from the lung to the heart. By doing this and also placing a tube with a blocking balloon into the artery going the lung it is possible to isolate one lung for treatment while the patient breathes with the other lung. Once the lung circulation is controlled, it is possible to “lock” 75% of the chemotherapy into the lung for at least 30 minutes. Since each lung holds about 1/20th of total body blood, it is possible to take a safe dose of an intravenous drug and amplify its concentration 20 fold. Currently a phase I trial is investigating the maximal safe dose that can be delivered to one lung. While very preliminary, the research had detected reductions in suffused lung tumors getting the higher doses while the same cancers in other parts of the body have grown. |