Circulation 76,548 • Volume 20, No. 3 • Fall 2005   Issue PDF

Brain is Target Organ for Anesthesia

Barry L. Friedberg, MD

To the Editor

The article “Down But Not Out; Doctors Disagree How to Best Keep Patients from Awakening during Surgery,” which recently appeared in the US News and World Report, was an excellent translation of technical lingo for the lay reader, but missed the fundamental point about BIS monitoring.1 The brain is the target organ for anesthesia. The traditional signs of depth of “sleep” (i.e., heart rate, blood pressure, breathing rate, tearing, grimacing, movement, and so forth), upon which I relied for the first 22 years of my career, do NOT measure the target organ.

Anesthesia is sometimes defined as, “the art of the controlled overdose.” Knowing that the traditional signs may be inaccurate, anesthesiologists are obliged to routinely over-medicate for fear of under-medicating. A recent study by Monk et al.2 associates a BIS value of less than 45 for more than 2 hours anesthesia time with an increased 1-year mortality.

While awareness under anesthesia is indeed a significant problem, practicing anesthesia without a BIS monitor may be a lethal problem!

Curiously, I have heard all of the arguments against BIS monitoring that I heard 26 years ago when I introduced the automatic blood pressure device (Dinamap®) to my hospital. The most telling argument then, as it is today, is, “If they have a machine that can take the blood pressure, for what will they need an anesthesiologist?” The Luddites are still with us. Dr. Sinclair was on the mark when he said, “Why not use the technology?” Fear of losing what remains of one’s professional status is the obvious answer.

Barry L. Friedberg, MD
Corona del Mar, CA


  1. Comarow A. Down but not out; doctors disagree how to best keep patients from awakening during surgery. US News & World Report 2005;139(5):52.
  2. Monk TG, Saini V, Weldon BC, Sigl JC. Anesthetic management and one-year mortality after noncardiac surgery. Anesth Analg 2005;100:4-10.