Strong Ion Diffnce.
About the Author
by "Grog" (Alan W. Grogono), Professor Emeritus, Tulane University Department of Anesthesiology
The 1952 Copenhagen epidemic affected about 3,000 people and, despite heroic efforts to provide manual ventilation, about 345 died. Most of the 3,000 patients were admitted to the Blegdam Hospital, an infectious-disease hospital. Although it seems hard to believe, the timing might have been even worse. Bjørn Ibsen, an anesthesiologist, had worked at the Massachusetts General Hospital. He knew that a child there had been treated with curare to control tetanus and had then been successfully ventilated manually through a tracheostomy. Accordingly he proceeded to manually ventilate a cyanotic girl with limb paralysis via a cuffed endotracheal tube in a tracheostomy. His insight was the basis for recruiting 1,500 medical and dental students to provide 165,000 hours of ventilatory support. Initially, there was no way of measuring the PCO2. Accordingly the high bicarbonate values were thought to indicate an alkalosis of unknown origin rather than a respiratory acidosis. Ibsen is generally credited with creating the concept of critical care medicine.
Our understanding of acid-base balance depends on numerous underlying inventions, discoveries and theories. Blood gas analysis is used frequently partly because it is now convenient, and partly because of the growth in our knowledge and understanding of acid base physiology.
Interest in acid base balance stems from its physiologic importance, from fascination in a subject which has exercised and challenged scientific interest during the last century and, regrettably, from the requirement to set and pass examinations
The history has been presented as a book, The History of Blood Gases and Bases by Poul Astrup and John Severinghaus, and as Six History Articles in the Journal of Clinical Monitoring (1985 and 1986): 1, 2, 3, 4, 5, 6. and also reviewed by Kenrick Berend (2018)
The critical events and participants are summarized in the Acid-Base Event List below which emphasizes several points:
See the section at the Bottom of this Page.
Medical School: I entered The London Hospital Medical College in 1953 – one year after the Copenhagen poliomyelitis epidemic. Fear of polio was understandable: critical care and formal recovery rooms did not exist. I enjoyed medical school but was not a particularly good student – focusing principally on writing, and participating in the annual Christmas Review. Several of us managed to fail a pharmacology course several times. We created a "failed pharmacology course tie" which we wore to the professor's remedial lectures. This failure makes an interesting contrast with my career choice employing drugs with and my creation, years later, of a mobile consisting of a history lesson of anesthetic molecules. Long after I had graduated, a chance meeting with the professor occurred when my wife and I were house-hunting. He opened the door and I believe I detected long dormant pain on his expression. We made no reference to the past and didn't buy the house.
Ether: I started my first training job in anesthesiology at the The London Hospital in 1960. There were only one or two ventilators in the entire suite of operating rooms and fear of the use of curare was common: "For patients that worry you – trust ether!" At the time, anesthesia gases were casually and freely released into the room. When I administered ether, particularly when dripping it onto a gauze mask over a child's face, I inhaled it and it was absorbed into my fat. My friends could smell it on my breath for many hours. After 13 weeks I abandoned anesthesiology in favor of obstetrics – because the obstetric job was associated with directing the Christmas Review. I made this switch even though I had already designed a new ventilator.
First Ventilator: Experience with the new balanced anesthetic approach using a blend of curare, nitrous oxide and morphine very rapidly convinced us trainees that this mantra about ether was outdated. The need for more ventilators was dire – arriving late in the operating room eliminated the chance of grabbing a ventilator and manual ventilation was tedious. This manual ventilation stimulated creativity. The oxygen and nitrous oxide exiting the flow meters could surely be stored under pressure until there was enough for the next breath. My first ventilator used wood and a rubber bellows and I suggested trying it on a patient. Sadly, as I then thought, wiser heads prevented my trial. I likened the mechanism to the tank above a men's urinal. It fills until a trigger causes a flush or, in this case, a breath.
Competition: At the time I was oblivious of almost identical and independent creativity by Howells and Manley, two other anesthesiology trainees in London. They both produced excellent minute-volume divider anesthesia ventilators that were widely adopted. Howells later became a colleague and a friend when I became a consultant at the Royal Free Hospital.
Critical Care: While completing my training at King's College Hospital, I became acutely aware of the need for Critical Care. The battle to find space, staff, personnel, and other essential resources was overwhelming. It also taught me another valuable lesson: it requires dedicated medical staff as well. Completing my training and devoting "spare" time to Critical Care was impossible – my wife and I were raising four children and rebuilding an old Victorian house with our bare hands.
Second Ventilator: My fascination with anesthesia ventilators eventually resulted in a New Ventilator/Humidifier. Now the anesthesia gas accumulated in a metal container – a pressure cooker. Rising pressure tripped a mechanism that released the gas to the patient. The prototype was used for years in the animal laboratory in the Upstate Medical Center, Syracuse NY. However, it was never a commercial success due to difficulty achieving the required reliability and growing concern about releasing high flows of anesthetic gases into the operating rooms.
First Acid-Base Diagram: In 1974, Hawke, Byles and I experimented with various diagrams to represent acid-base base balance. The magnificent but intimidating Siggaard-Andersen Alignment Nomogram provided us with data which allowed every possible combination to be plotted: PCO2 against pH, pH against Bicarbonate, Standard Base Excess against pH, Hydrogen ion concentration against Standard Base Excess, etc. All of these attempts produced awkward curves or misshaped clinical zones. Imagine our excitement when we plotted PCO2 against Standard Base Excess to produce straight pH lines and clinical zones like straight spokes of a wheel.
Meeting John Severinghaus: In 1984 Jack Aron made a generous endowment to honor his friends and I became the Merryl and Sam Israel Chair of the department of Anesthesiology. I was asked to invite a speaker and, to my delight, John Severinghaus accepted the invitation that formed the basis for our enduring friendship. Towards the end of his life Jack Aron developed Amyotrophic Lateral Sclerosis (Lou Gehrig's disease). He asked for my advice, which was disturbing but flattering. I would like to think I helped him decide what he should do.
More on Ventilators: Around 1988 Prof. Wilhelm Erdmann of the Erasmus University in Rotterdam visited me unexpectedly. He stimulated my interest in The Physioflex - a new electronic anesthesia machine, and invited me to join the design team. I was excited because among its many other innovations, it minimized waste gas liberation and allowed Oxygen Consumption to be measured. It was never sold in the US and was acquired by DrägerⓇ who eventually allowed it to vanish. I obviously brought bad luck to ventilators!
Another Acid Base Diagram: In the late 1990s John Severinghaus introduced me to Robert Schlichtig who had compiled an extraordinary set of acid-base values from 21 published reports of patients with purely acute or chronic metabolic or respiratory acid-base problems. From this he calculated regression equations which allowed us to update the original Grogono diagram to accurately locate the Clinical Zones.
This Website: I created the first version of this website in December 1998. It was hosted on the Tulane Medical Center website and remained there until 2005 when hurricane Katrina inactivated the Tulane servers for some weeks. The website has attracted several hundred links and many kind testimonials.
Alan W. Grogono
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