Merlin Larson, MD
@MerlinLarsonMD1
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Swede, wannabe Italian, Bad at classical guitar; anesthesiologist, Stanford and NIH trained. UCSF Faculty 30 years. Pupillometrist. Standard disclaimers.
California, USA
Joined August 2020
Anesthesia was discovered by dentists. But in the 1950s, anesthesia by dentists was not safe: Image is from Stuart Cullen’s book (1951). Lidocaine (introduced in 1949) has anti-epileptic properties in low doses (as contrasted with the older drugs, cocaine or procaine).
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When did the idea of “gas” as distinct from “air” originate? Jan Baptist van Helmont (1580 - 1644) observed that combustion produced “chaos” (later abbreviated to “gas”) that was different from air because it (CO2) would not support life. Other “gases” produce anesthesia.
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The citizens of Edinburgh have contributed ideas about how we now think about labor pain. In 1591, Effie Macalyean was executed for trying to relieve the pain of childbirth (Edinburgh). Generations later (1846), James Simpson promoted the same idea in Edinburgh, using chloroform.
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Christison’s classic book (1839) on poisons claimed that leeches died when used as treatment for opium toxicity (image). But leeches absorb oxygen through the skin- they don’t breathe. Leeches have opioid receptors that cause paralysis - they might look dead but are just fine.
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This year is the 250th anniversary of the discovery of oxygen by Antoine Lavoisier. Image: The opening page of this landmark publication. In 1794 Lavoisier was executed during the “Reign of Terror” following the French Revolution.
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Opioids do not depress the pupillary light reflex (image). See further discussion in “A Practical Guide to Portable Pupillometry”.
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Pontius Pilate was the Governor of Judea from 26-36 CE. He is known for the phrase “What is Truth”. In 1860, did Dr. W. K. Atkinson speak the truth about the discovery of anesthesia? (Image: A Calculus of Suffering, by M. S. Pernick, 1985). …(See Tweet 9/4/21, about Truth).
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Every decade has new.innovations for the anesthesiologist. In the 1940s, the innovation was tracheal intubation. Macintosh and Mushin discussed tracheal intubation and presented the problem with small ET tubes (see image) in their book “Physics for the Anesthetist” (1947).
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75 years from now, will anesthesiologists read our case reports and find them as bizarre as this one reported by Guedel in his book “Inhalation Anesthesia” from 1937?
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Can an anesthetist be technically skilled but scientifically stupid? Gardner Q. Colton (1814-1898) administered 121,709 nitrous oxide anesthetics (dental surgeries) without a death. He was not doctor and believed that 100% nitrous oxide delivered more oxygen than room air.
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See the anesthetist on the left with a brain, eyes, ears, and hands (Figure 26 from Faulkoner)? In a widely circulated article in Science (126:827-830, 1957), J.W. Bellville suggested replacing the anesthetist with a machine.
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The word rumination stems from Latin word “ruminatus” …to chew over again. Rumination can rarely be the ruin of physicians that manage life threatening emergencies.
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This chart shows the anesthetic deaths in England (1846 to 1950). It was constructed by W. Stanley Sykes, MD (1984-1961). Some of the deaths occurred under his care. He “burned out” of anesthesia mid 20th century in order to write medical history books and mystery novels.
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In this classic paper, Bernard described how the autonomic nervous system protects the “internal mileau” from changes in the external environment. Anesthetics interfere with many of these reflexes. Maintaining the “internal mileau” thus depends on the skill of the anesthetist.
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What’s with the anti-science rhetoric? Progress takes time. Poisoned arrows (image) were a mystery to the early explorers. Today, modern relaxants are used in all major operations. If you need surgery, thank the many government grants that made anesthesia safe.
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ChatGPT claims that general anesthesia blocks sensation and perception. But that is wrong. Measure the heart rate following the incision after induction of anesthesia with propofol. The increase in rate is sensation. The word anesthesia (without sensation) was poorly chosen.
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The person who secures the airway during CPR can then assess midbrain function by using a portable pupillometer (image). See discussion in “A Practical Guide to Portable Pupillometry”.
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Reflections, by Jane Moon, MD. April issue, Anesthesiology
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A submission in the 2025 California Society of Anesthesiologist’s essay contest discusses the herbal based anesthetic used by Hanaoka Seishu in 1804, 42 years prior to the introduction of ether. Here is an artists rendition of the surgery.
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lists these important events from the year 1846: 1. US declares war on Mexico. 2. US gains control of lands below the 49th parallel from Great Britain. They do not mention the most important discovery in the history of medicine (Boston: Oct 16, 1846).
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