a modern fairy tale, with apologies to Jonathan Swift and other satirists
by Barry L. Friedberg, M.D.
Disclaimer: Dr. Friedberg has no financial ties to Aspect Medical Systems, Inc. makers of the BIS monitor. He is not a stock holder, a member of the board or a paid consultant.
1) Goldilox - an iconoclastic, 'money grubbing' member of the Hebraic persuasion ('lox') who publishes the means to superior,
reproducible anesthesia patient outcomes but is not recognized or supported by the anesthesia establishment.
2) Bare - a naked, bare faced falsehood
a) Bare #1 - The ASA & AANA are genuinely interested in better patient outcomes
b) Bare #2 - 'Research' published in the 'peer reviewed' journals is untainted by corporate funding (i.e. drug manufacturers)
c) Bare #3 - Aspect's BIS monitoring is not a standard of care because its algorithm differs from Baxter's Physiometrix
In the original fairy tale, Goldilocks becomes tired after traveling through the forest and comes upon the cabin of the three bears.
Trying to get a nap, she rejects Papa Bear's bed as 'too hard,' Momma Bear's bed as 'too soft,' and Baby Bear's bed as 'just right.'
Hungry after her nap, she rejects Papa Bear's porridge as 'too hot,' Momma Bear's porridge as 'too cold,' but accepts Baby Bear's porridge as 'just right.'
And now the tale:
Long go but not too far away (actually in our own galaxy), Larson publishes a textbook with his mentor, Stewart Cullen (Cullen SC, Larson CP: Essentials of Anesthetic Practice Chicago, IL, Year Book Medical Publishers, 1974, p 82.), stating that, “We hold the basic premise that the less the involvement of the patient’s critical organs and systems (i.e. the lower the concentration of the agent, or the less ‘deep’ the anesthesia), the less will be the damage to the patient, whether this be temporary or permanent.”
30 years later, Outpatient Surgery Magazine publishes 'Minimally invasive anesthesia for minimally invasive surgery' (February 2004). Goldilox promises that patients will receive the benefits of general anesthesia (BIS 45-60), which are that they neither hear, nor feel, nor remember their surgery but are trespassed the least possible by titrating their propofol to BIS 60-75, sparing 20-30% of propofol that would have normally been giving based on changes in heart rate and blood pressure. Combining a lesser trespass with the dissociative effect, permits the surgeon to inject local analgesia without sending a pain signal to the patient's brain. The net effect of this approach is to provide reproducible, preemptive analgesia. Preemptive analgesia means when the propofol is turned off at the end of the surgery, the patient awakens with minimal to no postoperative pain. Providing pain relief without the use of either emetogenic agent (opioids or inhalational anesthetics) essentially eliminates postoperative nausea and vomiting (PONV), even in high risk patients (i.e. non-smoking females with prior histories of PONV and or motion sickness having elective cosmetic surgery of 2 or more hours in duration) WITHOUT the use of any anti-emetics!
Monk’s landmark study (Monk TG, Saini V, Weldon BC, et al.: Anesthetic management and one-year mortality after non-cardiac surgery. Anesth Analg 100:4, 2005.) associating 2 or more hours of BIS < 45 with an increased one year mortality was published in January 2005. The authors were quite clear that they had not established a cause and effect relationship between unnecessarily deep anesthesia and increased one year mortality. However, their findings were not dissimilar to studies about the effects of cigarette smoking and pulmonary disease of the late 1950s and early 1960s which also failed to demonstrate a 'cause and effect' relationship between inhaling toxic cigarette smoke and later pulmonary disease. In 2005, we know that anesthetic agents have some toxicity. Is it too much of a 'fairy tale' to imagine that administering anesthetic agents in amounts greater than is necessary to achieve amnesia and analgesia might produce adverse outcomes if we examine one year postoperative outcomes?
Prior to Monk, et al., anesthesiologists never considered the possibility of any postoperative patient mortality past 24-48 hours as having anything to do with anesthetic management. After Monk, et al., the practice of routinely administering routinely over medicating for fear of under medicating is no longer tenable! With a BIS, one can deliver a high quality, individually titrated, anesthetic without without it being 'too hot' or 'too cold.' BIS titrated propofol is 'just right.' BIS monitoring really is the standard of care if better patient outcomes are genuinely desired.