The concept of minimal anesthetic concentration (MAC) is 60 years old next year. (Anesthesiology 1965;25:302). Is it a clinically useful concept today? Several agents are used in combination today and this makes the vapor concentrations less relevant.

After treating postoperative pain with opioids, some patients say they feel as if they are 'in heaven'. Is pleasure the absence of pain? This text from a 1792 manuscript (V. Seaman) considers the question. This topic was also discussed by Friedrich Nietzsche (1844-1900).

Anesthesiologists encountered a fork in the road in 1942. One road was labeled 'Neuraxial block' for labor analgesia and the other road was labeled 'Twilight Sleep'. The neuraxial road was less traveled but they took it. It 'made all the difference'. See poem by Robert Frost.

'Tour Guides' will sometimes relate exotic, but false, stories about historical sites. These stories are amusing but not substantiated by official documents. But the guides are clever with cell phone cameras. Image: Taj Mahal - 2024.

Joseph Black (1728 - 1799) called CO2 'fixed air' because it precipitated as it passed through a solution of calcium hydroxide. Waters used soda lime to produce closed circuit anesthesia. Now the idea is used to remove tons of carbon dioxide from the atmosphere (image).

Insertion of gastric tubes during anesthesia can sometimes present a problem. Lundy described his method in 1945 (image from his book). But removal of the ET tube can be impossible when the proximal end of the gastric tube is enlarged.

The 'Taylor' spinal enters the IT space between L5 and the sacrum. It can be used when the lumbar approach is fused. This Figure from JA Taylor's 1940 paper (Journal of Urology, 43:561) illustrates the technique. The patient is prone. Taylor was a practicing urologist in NYC.

Dudley Buxton (1855-1931) introduced a new idea into anesthesia practice that eventually led to the creation of a new specialty: Anesthesiology. His idea was that the anesthetic method should not be routine but should be designed to fit the unique specifics of one case
(Duncan).

The idea of a printed scientific journal is on life support, after thriving for nearly 400 years. Henry Oldenburg (Secretary of the Royal Society in London) started the idea in 1641 (image).

75 years ago an anesthesiologist could hold a tight fitting mask for several hours (either hand). William Hamilton thought this skill was lost after tracheal intubations became popular in the 1940s (see text from his 1970 lecture). Did the LMA (1983) accelerate the problem?

Dagmar Nelson, CRNA was sued for illegally practicing medicine (1934). Her defense was that the surgeon directed the anesthetic and ordered her to deliver it. Arthur Guedel testified: 'surgeons cannot direct an anesthetic because they cannot look at the patient's eyes'. (Image)

This (30 min) 'introduction to ketamine' video was created by John Pender (1970). It cautions that expertise in airway management is necessary to use the drug. Now it can be purchased online and there is unsupervised use of ketamine. Deaths have occurred. dp.la/item/44db00160…

William Halstead (1852-1922) performed the first peripheral nerve block in 1884. He then started blocking his own nerves and became addicted to cocaine. He was 32 y/o when he wrote these nonsensical words describing regional anesthesia with cocaine (NY Med Journal - 1885).

There are 3 dangerous spaces in the vertebral canal into which a full epidural dose can be catastrophic: subarachnoid, intravenous, and subdural. Covino discusses the dangerous subdural injection and shows the spread of epidural dye in the subdural space (from 1985).

Adolph Hitler would not allow German citizens to receive the Nobel Prize. So he created his own prize: The German National Prize for the Arts and Science. One recipient of this prize (in 1937) was August Bier who was the first to describe spinal anesthesia (125 years ago).

Over 25 years ago an article in Anesthesiology (Vol 84, Pages 160-8) reported that sevoflurane at gas flows of 2L/min damaged the kidney. On this 2024 earth day it is time to reject this flawed concept and use this greenhouse gas (that damages the atmosphere) at low flow rates.

Comroe's 1959 book has this Table and text. A patient with restrictive lung disease has to breathe with rapid shallow breaths because of stiff lungs. To achieve alveolar ventilation of 4 L/min, the total ventilation must be 10 L/min because each breath has 150 cc dead space.

Comroe (1959) illustrates the several barriers that impede the diffusion of alveolar oxygen into the red blood cells. In his book 'The Lung' he mentions several diseases that prevent ambient oxygen from saturating hemoglobin in the pulmonary capillary bed.

1. Regional block. 2. Propofol. 3. LMA. 4. propofol infusion. Experienced physicians 100 years ago could omit the last 3 items by perfecting a calm demeanor (see Gwathmey, 1914).

Immobilon is a potent opioid that is 20,000 times more potent than morphine. It is used to immobilize large animals in the wild. This 12,000 lb elephant was given 4.5 milligrams through a 'flying dart' to take measurements and place ear tags. Human LD50 = 3 mcg.