Editor's Note: We're posting this story from our June 2003 issue because of a new study of the phenomenon.
- The heart-lung machine, first used on humans in 1953, revolutionized coronary surgery by giving doctors an hour or more to operate on a still heart. Previous techniques allowed only 15 minutes.
- Since the inception of the machine, medicine has recorded cognitive decline inpatients hooked up to it. The condition, later nicknamed “pumphead,” was thought to be short-lived and was often attributed to the general trauma of surgery.
- Recently, long-term studies of patients have shown that pumphead may worsen over time and persist for years. Many factors could be involved, but microscopic cell debris and bubbles generated by the machine are under suspicion.
The last thing I remembered was the cold room with a stainless-steel ceiling. I was about to undergo open-heart surgery, an experience shared by about 500,000 people in the U.S. every year. After the anesthesia took effect, surgeons made an incision in my groin to reach my femoral vein and artery. Through the vein they threaded a tube called a cannula into the right atrium, an upper chamber inside my heart. This tube, and another attached to the artery, was connected to a cardiopulmonary bypass pump, also known as a pump oxygenator or a heart-lung machine. A dose of heparin kept my blood from clotting as it traversed the machine’s innards. As the venous blood passed through the oxygenator, it was cooled to prevent tissue damage. My body temperature lowered to 25 degrees Celsius (77 degrees Fahrenheit)—deep hypothermia. Surgeons inserted an inflatable clamp into my aorta to seal it off. Two liters of cold potassium solution stopped my heart, and for the next two hours the machine took over. An eight-inch incision below my right breast allowed the doctors to pass cameras and instruments between my ribs and then to repair my congenitally defective heart valve.
I left the hospital a week later. The incision healed quickly and painlessly. In a couple weeks I was out and about on slow but successively longer walks. Within a month I was back in the gym. Mentally, however, I felt a bit hazy, a little disconnected and sometimes even lost. I soon learned that the physician’s warning, “You may be a little depressed for a time afterward,” would not do justice to the long, dumbfounding struggle against what seemed to be the sudden onset, at 51 years of age, of attention-deficit disorder or incipient senility. Adrift in a clueless no-man’s-land, I felt my moods range from querulous to despondent. I couldn’t muster the concentration to deal with the problem. I just wanted to be able to think. Think anything.