The 34th Rovenstine Lecture

Abstract

(Pierce) Associate Clinical Professor of Anaesthesia, Harvard Medical School; Chairman Emeritus, Department of Anaesthesia, Deaconess Hospital.Received from the Department of Anaesthesia, Deaconess Hospital, Boston, Massachusetts. Based on the author's E. A. Rovenstine Memorial Lecture, presented at the annual meeting of the American Society of Anesthesiologists, Atlanta, Georgia, October 21-25, 1995.Address correspondence to Dr. Pierce: Chairman Emeritus, Department of Anaesthesia, Deaconess Hospital, One Deaconess Road, Boston, Massachusetts 02215.Address electronic mail to: [e-mail] words: Anesthesia: risks; safety. History: anesthesia patient safety.IT is indeed an honor and a privilege to deliver this eponymous presentation, the 34th Rovenstine Lecture.In preparation for this lecture, I have read most of the previous published discourses in the series. By custom, speakers begin with a few comments about Dr. Rovenstine, who was born in Indiana in 1895 and died in New York City in 1960. Rovey, as he was affectionately called by his friends, was urged to enter the young field of anesthesia by Arthur Guedel, who was then on the medical faculty at Indiana and who sent him to train with Ralph Waters at Wisconsin. Rovenstine was one of Waters' first two residents. Several previous speakers have examined their anesthesia "family" descent from Waters and Rovenstine. Although I never met either, I may be part of the family because the chairman at Pennsylvania, where I trained, was Robert Dripps, also a resident with Waters and later with Rovenstine.Dr. Waters dispatched Rovey to Bellevue Hospital at the beginning of 1935, responding to an urgent request by the Chief Surgeon of the New York University Division. Over the next several years, Emery A. Rovenstine became famous as an anesthesiologist, as far as I know, the only one ever profiled in The New Yorker. [1-3]Perhaps his greatest role was in training young, scholarly anesthesiologists to become chairmen of academic departments. In addition, Dr. Rovenstine must be considered one of the key figures in the creation of anesthesiology as a full medical specialty. Perry Volpitto and Leroy Vandam, in their 1982 book The Genesis of Contemporary American Anesthesiology, place the early giants into two groups, first, the visionaries, including Guedel and Waters. [4]The second, the activators, contains Rovenstine.As the foregoing comments suggest, Rovenstine's professional life calls forth the enduring themes of leadership, vision, and dedication to the advance of medical practice. These themes are the real spirit of the Rovenstine Lectures, and they provide a purpose and continuity that remain strong and relevant--long after the passage of time has diminished the early linkages of professional kinship and memory. In keeping with this essential spirit, my lecture today will once again visit the basic themes. I will do so by exploring the pursuit of patient safety in anesthesia, an objective that has been the chief goal in my professional career. Although my remarks will present an admittedly personal view, I hope they will convey some general lessons and insights that will make this lecture a worthy tribute to Dr. Rovenstine and the lecture series.The first day I administered anesthesia as a resident in training was on July 1, 1954, in one of the gynecology operating rooms at the Hospital of the University of Pennsylvania. The instructor was James Eckenhoff, simply a wonderful teacher. Years later, in a lecture given before the Royal Society of Medicine on the importance of leadership, he discussed its role in promoting safety. [5].What was it like to practice anesthesia in 1954? How safe did it seem? The department at Pennsylvania was a major proponent of cyclopropane anesthesia, but the other available agents included diethyl ether, divinyl ether, ethylchloride, trichlorethylene, nitrous oxide, ethylene, and on rare occasion, chloroform. Use of intravenous thiopental was common, as was rectal anesthesia with a variety of agents such as tribromoethanol (Avertin), paraldehyde, or chloral hydrate. Single-dose and continuous spinal anesthesia with procaine or tetracaine were widely employed, even for upper abdominal surgery.Intravenous solutions were seldom begun until after the patient was asleep. Cyclopropane induction usually was performed with only the agent and oxygen. With ether, the patient was given 100% N2O for several minutes. The resultant hypoxia plus the addition of carbon dioxide to the circuit produced hyperventilation, hastening ether uptake. Induction frequently was time-consuming. Anesthesia for tonsillectomy was with open drop ether and no endotracheal tube. I clearly remember one incident when Dripps, demonstrating ether induction to a group of medical students, saw his patient, a strapping young male, sit up and step off of the table.At Barnes Hospital in St. Louis, where I had been a surgical intern, the time required for ether induction, before I could prepare the patient, was often 30 min or more. Impatience with this vexing delay was one of the factors that pushed me into becoming an anesthesia resident. Some of the surgeons at Barnes performed thyroidectomies while the nurse anesthetist gave only thiopental, total doses approaching 2 g or more. These patients, of course, slept for a considerable period after surgery. Dripps, in contrast to Beecher at the Massachusetts General Hospital, encouraged use of the recently available neuromuscular blocking drugs, d-tubocurare, succinylcholine, gallamine, and decamethonium. However, prolonged blockade with decamethonium was common; because we had no ventilators, it fell on the residents to ventilate the patient's lungs postoperatively in the then new recovery room, using an anesthesia machine.Intubation of the trachea was not common, except when necessary, as in anesthesia for thoracic surgery. Even thyroid resection was performed while anesthesia was administered via a mask. I remember worrying about having one of my fingers cut if the surgeon slipped with his knife. When residents were allowed to intubate the trachea, more often than not the tube had no cuff; rather, the pharynx was stuffed with gauze. If the anesthesiologist did want a cuffed tube, it was necessary to insert the cuff over the end of the endotracheal catheter. As you can well imagine, it was not unusual for the cuff to be dislodged, sometimes to remain in the trachea.What of the anesthesia machines? At Pennsylvania, several models were used, including Ohio, Heidbrink, and Forreger, with its water manometer. No resident was ever fully inducted into the club until he had opened the oxygen valve on a water manometer Forreger with the flowmeter previously left fully on, thus blowing water all over the operating room. There were no piped gases; the tanks on the machine were, therefore, all-important.What of intraoperative monitoring? It was not much different from the days of John Snow, who in the 1850s had encouraged observation of the pulse, respirations, and pupils. The only additional techniques in common use were the Riva Rocca blood pressure measurement and occasionally, in pediatric patients, a precordial stethoscope. Electrocardiograms were unavailable except under the most rare circumstance, when an old mahogany Sanborn machine would be wheeled into the operating room from the electrocardiogram station. However, it almost never worked because of the effect electrical interference had on the stylet. I never saw a sample of blood for blood gas analysis obtained in a clinical setting, because blood gas measurements could only be made in a research laboratory using the Van Slyke manometric apparatus. Cardiac arrest, not an unusual occurrence, was treated with open thoracotomy; closed chest compression had not evolved. Defibrillation was with alternating current.I well remember the arrival, while I was at Pennsylvania, of the first machine with Lucien Morris' copper kettle. Suddenly, residents were able to give 60% ether instead of struggling with warm water around the glass vaporizer trying to reach an ether concentration of 5%. As a result, the incidence of ether overdose skyrocketed. Almost every Monday afternoon at the complications conference there was at least one presentation of near cardiac arrest. Moreover, in those days, in all anesthesia departments, I am sure, when a patient did not survive, the families were simply told that "old Joe" just didn't tolerate the anesthesia--"too bad."By today's standards, cardiac anesthesia was particularly primitive. Because there were no plastic intravenous catheters, a number-14 metal needle was inserted in the dorsum of each foot, where the likelihood of dislodgement was less than in the arm. Monitoring, again, consisted of Riva Rocca blood pressure measurement, observation of respiration, and a finger on the pulse. Often, blood pressure could be obtained only by observing oscillations. Electrocardiography was rarely attempted. Thomas Cannard, one of our staff anesthesiologists, built the first permanent electrocardiogram machine in our operating rooms from a kit.Recovery rooms were by that time in use in many American hospitals, but they were small and primitive. They were not to be found in the United Kingdom or Europe. If a patient were cyanotic, it was difficult to know whether it was central cyanosis or a result of peripheral vasoconstriction due to shivering. Some anesthetists, to make the differential diagnosis, would scratch the chest with a needle, observing whether the resultant bleeding was bright or dark blood.Anesthesia machines were certainly less safe than today. Heidbrink flowmeters with disc floats were difficult to read accurately because the calibration was too small. There was no standardized arrangement for the gas flowmeters; the oxygen flowmeter was sometimes on the left side, sometimes in the middle, and sometimes on the right. Pin indexing was new; not all machines had been fitted with the pins. Moreover, sometimes the pins were dislodged, allowing attachment of the wrong tank. This situation was a setup for catastrophe, because each machine often had cylinders of oxygen, nitrous oxide, cyclopropane, ethylene, carbon dioxide, and helium. Ventilators were not available, except for primitive ones with a single pressure setting or foot-operated bellows.What, then, was the status of anesthesia patient safety in 1954? From a somewhat humorous standpoint, it was well described in the preface of Stanley Sykes' wonderful essays, "The First Hundred Years of Anesthesia." [6]He quotes Lincoln, from the Gettysburg Address: "It is for us, the living, rather to be dedicated here to the unfinished work which they who fought here have thus so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us, that. . .we here highly resolve that these dead shall not have died in vain."An enormous awakening was also at hand in 1954. It began with the huge controversy that greeted the publication of the paper by Beecher and Todd. "A Study of the Deaths Associated with Anesthesia and Surgery," which appeared in the July 1954 issue of Annals of Surgery in my first month as an anesthesia resident. [7]I remember the anger in Dr. Dripps' voice as he refuted the data, especially the statement that the study "strongly suggests an inherent toxicity" in the neuromuscular blocking drugs. The publication was one of the first to add a denominator when considering anesthesia deaths; evaluations of the previous 100 yr were limited to analyses that did not consider the number of anesthetics administered. Beecher examined nearly 600,000 anesthetics administered over 5 yr in ten university hospitals. He noted who the anesthesia caregivers were, what techniques and agents were used, and whether the trachea was intubated. The incidence of anesthesia mortality was found to be 3.7 per 10,000 anesthetics, with anesthesia as a primary cause.One year later, also in Annals of Surgery, 16 distinguished American anesthesiologists published a "Critique of "A Study of the Deaths Associated with Anesthesia and Surgery." [8]They stated, "[We] believe that many of the important conclusions drawn by Beecher and Todd are not justified on the basis of the statistics presented. . .," and suggested that missing data in the Beecher paper, such as site of operation, depth of relaxation required, duration of anesthesia and operation, and severity of surgical trauma, negated many of the conclusions. They, as had Dripps and Manny Papper at Columbia, objected strongly to the suggestion that use of "curare" results in higher mortality rates. A few years later, in a retrospective study initiated after the Beecher paper, Dripps analyzed the role of anesthesia in surgical mortality at the University of Pennsylvania. [9]Among some 33,000 patients given either a general anesthetic to which neuromuscular blockers were added or a spinal anesthetic, there were no deaths attributable to anesthesia in ASA physical status I patients, although the overall mortality rate with anesthesia as the primary cause was 11.7 per 10,000 anesthetics.Here, then, were two decades of numerous studies worldwide of anesthesia deaths, with mortality rates ranging from 1 to 12 per 10,000 anesthetics. Anesthesia study commissions, examining postoperative deaths, proliferated. A well known one was directed by Otto Phillips in Baltimore, where during a 5.5-yr period ending in 1959, they found anesthesia to be the principal cause of mortality in some 6% of the deaths and a contributing factor in 13%. [10]Phillips declared death from anesthesia a major public health problem. He opened a review of anesthesia mortality with an anonymous quotation: "You members of the medical profession, gentlemen, are in a favored position--the world acclaims your successes and flowers cover your failures." [11].Perhaps the most important result in all of this was the increased interest among anesthesiologists in improving anesthesia outcomes. In 1962, I became interested in anesthesia patient safety. I had joined Leroy Vandam at the Peter Bent Brigham Hospital as de facto Vice Chairman. In his inimitable way, one day he assigned me the subject, "anesthesia accidents," to be given as a resident's lecture. I still have notes in my files from that talk, which began as a collection of anesthesia mishaps that I knew about personally, somewhat akin to a chapter in Sykes' Essays, [12]"37 Little Things Which Have All Caused Death."Arthur Keats, who had been an anesthesia resident at the Massachusetts General Hospital during the period that the Beecher study was undertaken, criticized anesthesia mortality studies. He argued in 1970 that, "The relative risk of all anesthetics commonly used today remains unknown." [13]He stated that, "for most deaths, assignment of the relative roles of anesthesia, surgery and patient disease is based on retrospective assumptions, hindsight judgment, bias, and incomplete information." He opened his paper with a quotation from Sir William Osler, "Errors in judgement must occur in the practice of an art which consists largely in balancing probabilities."Later, Dr. Keats continued his thesis, in the 1978 Crawford W. Long Memorial Lecture at Emory [14]and the 1990 Seldine Lecture. [15]He reemphasized that we in anesthesia are unable even to define an anesthetic death. Bias often exempts anesthetic agents from adequate risk/benefit analysis. He particularly criticized the classic 1948 article, "Deaths Under Anesthetics," by the eminent British anesthetist, Robert Macintosh, who stated that all anesthetic deaths are preventable, the result of errors. [16]Dr. Keats wrote, "Thirty years of self flagellation in the form of anesthetic mortality studies have generated an abundance of 'errors'. . ., all published estimates of the incidence of error or the incidence of anesthetic deaths are now unacceptable. . .Demonstration of a cause-effect relationship is absolutely essential if any secure knowledge of mechanisms of anesthetic deaths is to be achieved." He cited the discovery of new mechanisms for anesthesia death, such as malignant hyperthermia and succinylcholine-induced hyperkalemia. Dr. Keats concluded that we must rid ourselves of error bias.William Hamilton, Keats' great friend and hunting companion of many years, challenged, in an editorial, the implication that drugs per se are responsible for an important number of anesthetic deaths. [17]He agreed that much bias had been present in anesthesia mortality evaluations, especially equating departure from current clinical practices with error. In contrast, Dr. Hamilton believed that anesthesiologists had carefully evaluated risk/benefit concepts after review of death reports, as in halothane hepatitis, for example. He stated that, whereas we previously tended to blame drugs or the patient's disease when anesthesia went amiss, we correctly recognize the ever increasing importance of human error; "To blame an undiscovered or unexplained acute toxic effect of a drug, an idiosyncratic reaction, or divine intervention, as would appear to be Dr. Keats' thrust, is very when we know that can result in He stated that the controversy Keats and him the relative role of drugs as in to on the part of the anesthesiologist and concluded that . is important to know whether anesthetic deaths attributable to error to or per . . my error is near the I have the Keats and Hamilton because it remains Moreover, I also believe the is to the almost use of anesthesia mortality studies to anesthesia was in 1978 with the publication of first paper incident analysis to used in during had a effect on safety that even simply of mortality rates as the major of anesthesia he stated, with factors that may have to with a few not been previously no study has on the of the that or its with of for this first study using the incident in anesthesia were obtained from of staff and resident anesthesiologists at a In a paper published in the was to anesthesiologists, and nurse from in which of were 1978 the of and factors are on his to the likelihood of an incident and Use and the and preparation and and work on incident the "The or on opened the you are to into anesthesia, you are on a and you not do if you can it in any General anesthesia is safe most of the but there are from human and a of This patients will or of patients who had anesthesia the stated, "The you have just are of a they never knew in In on the a patient was left in after the error in off oxygen rather than nitrous at the end of an in the the one of the that is a in New York City where there are two anesthesia operating appeared and do they do The they and a was a for anesthesia patient safety At the I was First Vice of the American Society of and to a new ASA the on and was the first Chairman. The ASA of course, been in for some time with its on but never before had the of patient safety been so by our its first the a of patient safety still with me as The just by Robert is at the It will be to all United anesthesia by and I the first on Anesthesia and in Some anesthesiologists from the United and was and controversy among the was especially considering use of the of greatest was in the of and mortality meeting has been every 2 yr Anesthesia was as a result of the of a safety to other such as the were because of the that controversy would has from a of the and risk nurse anesthetists, and from the and the the American of and the American Medical certainly not in the of the ASA at that The remain the that will provide a of anesthetic that will the number of anesthetic and of and about the and of anesthetic with an of is in its with John as The has research in patient of more mortality have from the United where John and a anonymous to anesthesia deaths with surgery. was published in was considered or of mortality in one or two per 10,000 and to be in nearly 1 per was their that of patients were not by an anesthesiologist, did not have blood pressure did not have the machine by the anesthesiologist before beginning anesthesia, and did not have intraoperative with the The next in the was the first of the into by the of and the of of and examined deaths during 12 in health In that death attributable to anesthesia was only per 10,000 anesthetics, a far less than the The that, of the the anesthetic was less than Some of were to have been or analysis of anesthesia mortality nearly the yr of this lecture is that from New overall death rate in which factors under the of the anesthetist or to the was to be about 2 per 10,000 in 1 per 10,000 in and per 10,000 in the United it is not to of anesthesia mortality in the I just described because of our medical and nearly The important by on cardiac due to anesthesia at the Medical of over anesthetics in which there were cardiac an incidence of per 10,000 anesthetics. that the risk for surgery was than that for as it was also for pediatric patients to provide adequate was responsible for of the cardiac a in which he added data from additional years and then the total into two decades this in anesthesia the It be noted that the began 5 yr before and into common One in that period was the publication of first analysis of suggested general for the in first, use of to and second, in the number and of anesthesia and use of anesthesia ASA a major American to anesthesia also of the at which then Professor of at the University of discussed his examining closed anesthesiologists in the of They were published in a of Anesthesia by and of medical in the and the of in the suggested the to closed on a I remember with on to the data collection and that the be given to the ASA on which did in the then as well as has "The relationship of patient safety to was to If patients were not they would not and if the for patient could be then rates In the beginning it as if it would be difficult to to over their closed data to However, of the at St. and was for to review the was also an at the meeting and was an of the Robert then also at the University of joined the to in the analysis. It was that be published in early on, anesthesiologists were able to the Massachusetts the of and the New Medical to provide most important of the Study is in the analysis of the single of some of the The first mechanisms of for about of the total and difficult The of were before of and on of was often particularly in or permanent in of the with only of the remaining this particularly The that would have in of the with only around in the and believe that the of and has been with