The evolution of human resource needs in the USA

Best Practice & Research Clinical Anaesthesiology Vol. 16, No. 3, pp. 423±441, 2002

doi:10.1053/bean.2001.0224, available online at http://www.idealibrary.com on

7 The evolution of human resource needs in the USA John R. Moyers

MD

Professor Department of Anesthesia, University of Iowa College of Medicine, Iowa City, Iowa 52242 USA

The development of the speciality of anaesthesiology in the USA over the last half-century has seen a signi®cant growth in the number of anaesthesia departments and trainees. With no comprehensive national planning policy for physician human resources in existence, the number of anaesthesiologists has been determined by other things, such as market forces and capacities of the training programme. The American Society of Anesthesiologists has doubled in size in the past 15 years. The proliferation of anaesthesiologists has certainly been bene®cial in terms of safety and access to anaesthesia care. However, the recent prospect of too many anaesthesiologists for the future has led to wide oscillations in the number of trainees and employment opportunities. Key words: anaesthesiology; education, medical, graduate; manpower, health; United States.

The United States, unlike many other countries, does not have a national planning policy for human resources in the context of physicians. There is little governmental direction and lack of societal understanding of the workforce engaged in the delivery of anaesthesia services. Currently, there are almost 150 residency training programmes sponsored by hundreds of hospitals across the USA. The training programmes are regulated by a loose confederation of quasi-governmental and voluntary agencies such as the Accreditation Council for the Graduate Medical Education and the American Board of Medical Specialties. In the past, anaesthesia has traditionally been a speciality of under-supply. However, in the mid-1990s anaesthesia found itself, because of market forces and for a variety of other reasons, with the prospect of a future with an abundance of anaesthesia personnel. These estimates did not necessarily predict too many anaesthesiologists but, because of the presence of nurse anaesthetists, predicted an over-supply of total anaesthesia personnel. Medical students in this country reacted rapidly and chose post-graduate training in other speciality ®elds. The market then over-corrected in just a few years, and currently there are many more positions that there are residency graduates to ®ll them. Consequently, a challenge exists for the development and understanding of a human resource policy for the speciality of anaesthesia. This chapter describes past developments and the present state of the anaesthesia workforce, and also attempts to elucidate the determinants of the future workforce in anaesthesia. 1521±6896/02/$ - see front matter

c 2002 Elsevier Science Ltd. All rights reserved. *

424 J. R. Moyers

CURRENT HUMAN RESOURCES IN ANAESTHESIA IN THE USA Anaesthesiologists A few self-trained, physician pioneers at the beginning of the 20th century, utilizing the evolution of anaesthetic agents, instruments and techniques, led to the establishment of a unique body of knowledge pertaining to anaesthesiology. These visionaries formed organizations fostering a common interest in anaesthesia and argued for formal courses in anaesthesiology in medical schools. Sidney O. Goldan of New York is thought to have been the ®rst specialist in anaesthesiology, and by 1900 was the author of seven articles in the ®eld. He believed that the intraoperative welfare of the patient was at least as dependent upon the skills of the anaesthesiologist as upon those of the surgeon. In 1905 the Long Island Society of Anesthetists was founded; this developed into the New York Society of Anesthetists in 1911. This organization eventually became the American Society of Anesthetists. Because `an anesthetist is a technician' and `an anesthesiologist is a physician who is an authority on anesthesia and anesthetics', the American Society of Anesthetists became the American Society of Anesthesiologists in 1936. The International Anesthesia Research Society had been founded in 1925 and the American Board of Anesthesiology in 1938. In 1945 there were just under 2000 members of the American Society of Anesthesiologists, while today there are over 37 000. In the middle part of the 1900s Ralph Waters from Wisconsin, and others, created formal departments of anaesthesiology with collaborative research linkages with pharmacologists and physiologists in basic science departments. By the middle of the century, with the development of unique knowledge, recognition of trained specialists, and the formation of professional organizations, anaesthesiology had emerged as a distinct medical entity in the USA.1,2 Anaesthesiology residency programmes began training substantial numbers of postgraduate medical students after 1950. With the aid of external funding, particularly from the National Institutes of Health, relevant research developed and anaesthesia departments thrived.3 Between 1950 and 1995 there was a steady growth in the number of anaesthesia residents and, subsequently, the number of anaesthesiologists in the USA (Figure 1).4,5 The number of anaesthesia residency programmes remained relatively stable between 1975 and 1995, but the average number of residents per training programme was increasing. The larger number of residents within each department was due to the expansion of anaesthesia subspeciality areas, a proliferation of anaesthetizing locations within each training centre, and increasing federal funding for graduate medical education. During the past 25 years in the USA from 3±4% of medical school graduates have entered the ®eld of anaesthesiology. In addition to the American students, large numbers of international medical graduates have been entering the anaesthesia training programmes. In 1980 the report of the Graduate Medical Education National Advisory Committee supported the previous growth in the number of anaesthesia trainees and predicted a supply±demand equality for anaesthesiologists in 1990. Furthering growth was a good economic climate for practising anaesthesiologists, and many established outstanding anaesthesia departments which attracted the best graduating medical students. In addition, in the late 1980s there were leaders in anaesthesiology in the United States who viewed anaesthesia as the practice of medicine and supported the goal of an all-physician anaesthesia workforce. All of these factors coalesced to produce the current number of over 24 000 active anaesthesiologists in the United States. Many anaesthesiologists practising today have PhDs, have completed advanced training in subspeciality areas in anaesthesia and may have board certi®cation in other specialities. The proliferation in numbers through 1995 was slowed by

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Figure 1. Anaesthesiology residents in the United States, 1974±2000. PGY ˆ postgraduate year. Data collected from the American Society of Anesthesiologists, the American Board of Anesthesiology and the American Medical Association.

Number of trainees

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Human resource needs in the USA 425

426 J. R. Moyers

workforce studies, health care reform, and articles in the lay press6 ± more about this later. Nurse anaesthetists Some argue that the development of a speciality of anaesthesiology may have been slowed due to the presence of nurse anaesthetists. Indeed, anaesthesiology was originally viewed by some surgeons as a technical undertaking which they had practised as junior house ocers that could be delegated to ward nurses or hospital orderlies. However, just as some physicians in the early part of the century saw the importance of the anaesthetist, so did many nurses. Throughout the country in the metropolitan hospitals and in small, hospital-based nurse anaesthesia schools, Roman Catholic Sisters received training in anaesthesia. Many of them went on to productive careers in community hospitals. It became economically sound for hospitals to employ a trained anaesthesia nurse who had developed skills through daily activities rather than rely upon physicians or others who administered anaesthesia only rarely. Many prominent surgeons began schools of nurse anaesthesia and directed their training. By 1920 several schools for nurse anaesthetists had been established and were ¯ourishing. There were 17 schools for nurse anaesthetists in 1940, and on the same date there were only 87 diplomates certi®ed by the American Board of Anesthesiology. By 1970 there were 200 schools for nurse anaesthetists predominantly in rural and community hospitals.7 The number of schools plateaued in 1995, followed by a modest decline in the number. Since then, there has been an attempt to improve the quality of training for nurse anaesthetists, with more schools associating with colleges of nursing and universities and more requiring a master's degree. Other reasons for the fall in numbers of schools for nurse anaesthetists were an increase in the number of anaesthesia residents, a ®nancial incentive accruing to the medical centre from federal graduate medical education funding for physician anaesthesia trainees, and academic health centres perceiving more prestige in having anaesthesia residency programmes.1 Nurse anaesthetists are registered nurses who hold a licence limited to the practice of nursing. Many have attended 4 years of college, usually receiving a Bachelor of Science in Nursing. They then complete a minimum of 1 year as a nurse in a critical care setting in an intensive care unit, emergency room, or post-anaesthesia care unit. Training in nurse anaesthesia usually lasts 24 months, with a minimum of 450 classroom hours and at least 800 hours of supervised clinical experience. Most of the schools o€er a master's degree. Approximately two-thirds of the current membership of the American Association of Nurse Anesthetists have college degrees, and a quarter have a master's degree.8 The majority of nurse anaesthetists in the USA work in the operating rooms where they are medically directed by an anaesthesiologist. Anaesthesiology assistants Anaesthesiology assistants are physician assistants who deliver anaesthesia under the direction of an anaesthesiologist. The concept arose in the early 1970s when it appeared unlikely that there would be adequate numbers of anaesthesiologists in the future. Anaesthesiology assistants are college graduates who often come from the ranks of other allied health care practitioners, such as nurses, medical technologists, or respiratory therapists. They complete 2 years of technical training at an academic health centre provided by the faculty of an anaesthesia residency programme. When they have completed their training they have earned a Master's in Medical Science.

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Approximately 15% of anaesthesiology assistants have gone on to medical school where almost all have become anaesthesiologists. The schools for anaesthesiology assistants in Case Western Reserve University in Ohio and Emery University in Georgia have produced over 400 graduates in total.9 Some of the anaesthetic care in the USA is performed by general practitioners and other physicians who have had little or no formal training in anaesthesiology, as well as by some dentists, many of whom have had formal courses in training in the administration of anaesthesia. REPORTS AND RESEARCH ON HUMAN RESOURCES IN ANAESTHESIOLOGY In 1980 the ®rst conference report on human resources in anaesthesiology was published. The report of the Graduate Medical Education National Advisory Committee (GMENAC) emanated from a federal advisory panel studying the nation's supply of physicians and included anaesthesiologists.10,11 They employed a needs-based model to project physician needs in anaesthesiology, nuclear medicine, pathology, neurology, radiology and physical medicine and rehabilitation for the year 1990. Nurse anaesthetists and residents were included in the estimate. The study predicted that from 80 to 95% of the anaesthetics would involve an anaesthesiologist, and the ratio of supervision would be constituted as one anaesthesiologist supervising two nurse anaesthetists. The report included the activity of the anaesthesia faculty in teaching, research and administration as well as the e€orts of anaesthesiologists in critical care, pain and respiratory therapy. The GMENAC study projected the need for 16 491 fulltime equivalent anaesthesiologists for surgical anaesthesia activities by the year 1990. They further estimated a requirement for 811 full-time anaesthesiologists for obstetric anaesthesia, 827 for intensive care, 198 for pain medicine, 2950 for research and administration and 2475 full-time equivalents for teaching activities. The report calculated a need in 1990 for a total number of 22 143 full-time anaesthesiologists. Their ®gures suggested a slight shortage of anaesthesiologists for that year based on need. Their prediction in 1980 of the need for 22 143 anaesthesiologists for the year 1990 was very close to the actual number of active anaesthesiologists. Health care reform in the United States began in the mid 1980s when the cost of medical care was rising faster than the rate of in¯ation. There were increasing numbers of medically uninsured or under-insured citizens in the country. Also at that time, the workforce of physicians consisted of approximately 70% specialist physicians and 30% general physicians. Many leaders were calling for the reorganization and restructuring of health care because the growing number of specialists employed increasingly complex technology which led to further increases in medical costs. In 1986 the Council on Graduate Medical Education (CoGME) was chartered to advise Congress on graduate medical education and the workforce in health care. CoGME was one of the few connections between specialist physicians and federal funding. In 1992 an average of $78 000 was spent for each resident in graduate medical training in the USA totalling over 5 billion dollars of Medicare money.12±16 Because of these factors, CoGME recommended that 50% of graduate medical education training be in general medical ®elds and that the total number of resident training positions be reduced. They proposed to limit the total number of ®rst-year residency positions to a number equal to 110% of US medical graduates, thereby reducing the number of international medical graduates. At that time about 25% of the medical residents in the USA were

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international medical graduates. Fifty percent of the total residency training positions would be allocated to ®elds in general medicine. The CoGME report, and others similar to it predicted an over-supply of specialist physicians of as many as 170 000 by 2000.17 The recommendation of the CoGME report was embraced by many public groups, physician organizations and agencies of the government; it had an e€ect at the time on resident numbers, but never came to fruition. In 1994 the American Society of Anesthesiologists sponsored a workforce study conducted by Abt Associates, Inc. with a panel of anaesthesiologists, nurse anaesthetists and other physicians.18 The `Abt report' was a needs-based, practice-sensitive model that projected estimates for the anaesthesia workforce for the year 2010. The projections were based upon the predicted needs in surgical anaesthesia, obstetric anaesthesia, pain management, intensive care, education, research and administration. The report made assumptions about hours worked per week, retirement age, US population growth and birth rate. Birth rate was predicted to remain fairly stable over the ensuing 15 years, but with a large increase in the geriatric population. The study was based on the premise that surgery would be performed for the same indications at the same rate in 2010 as in 1994. All of these data led to the conclusion that there would be an increase in sicker, older patients having surgical procedures particular to the geriatric population. Figures used to predict human resource needs were put into one of four major practice scenarios, because the practice mode became the single most important predictor of physician needs: 1. The physician intensive model: 75% of anaesthesia procedures with physician only, 20% with a team of anaesthesiologists and nurse anaesthetists, and 5% with only a nurse anaesthetist. 2. The ®rst team model: 45% of anaesthesia procedures with physician only, 45% with a team of anaesthesiologists and nurse anaesthetists, and 10% with only a nurse anaesthetist. 3. Second team model: 25% of anaesthesia procedures with physician only, 65% with a team consisting of two nurse anaesthetists and one physician, and 10% with only a nurse anaesthetist. 4. CRNA (Certi®ed Registered Nurse Anesthetist) intensive model: 10% of anaesthesia procedures with a physician only, 80% with a team of typically more than two nurse anaesthetists per physician, and 10% with only a nurse anaesthetist. Using these four di€erent scenarios the report predicted that the number of anaesthesiologists required for 2010 ranged from 14 351 to 34 093, if a retirement age of 65 years is assumed, with anaesthesiologists working between 50 and 62 hours per week. The wide range in predictions is dependent primarily upon the di€ering numbers of nurse anaesthetists involved in operating room care of patients across the di€erent models. Using these ®gures, the number of anaesthesia residents required per year ranges from 100 to 1242 (Figure 2). The total number of anaesthesia residents in the USA from 1974 to 1996 is depicted in Figure 1. The number of graduating anaesthesia residents in 1994 in the nation far exceeded the projection of resident need by any model of the Abt study. However, a similar study by Abt Associates for paediatrics predicted an over-supply of paediatricians in the United States which never materialized.19 Presumably, market forces caused the adjustments in paediatric resident numbers to avoid the surplus. The same is apparently happening today in anaesthesiology. A `Contemporary Issues Form' in anaesthesiology in 1996 by Reves et al reviewed several predictive models of resident workforce in anaesthesiology.16 This report arose

Human resource needs in the USA 429

1400

Projected Total Training Needs for Anesthesiologists 1994-2010 (1 FTE = 50 hours/week)

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Retirement age Figure 2. Predicted training needs for anaesthesiologists, 1994±2010, using di€erent stang models and retirement ages and assuming a 50-hour working week. CRNA ˆ certi®ed registered nurse anaesthetist; FTE ˆ full-time equivalent. Reproduced with permission from the American Society of Anesthesiologists.

from an American Society of Anesthesiologists/Society of Academic Anesthesia Chairs Task Force which reviewed several approaches to predict the number of anaesthesia residents necessary for the early part of the 21st century. The report ®rst applied the 50% generalist policy gleaned from the Council on Graduate Medical Education report on anaesthesiology which would have reduced the 5400 anaesthesia residents in 1996 to 2900 over the next few years. Their analysis suggested 996 anaesthesia residents per year for each of the 3 years of clinical anaesthesia training, an over 40% reduction. From these ®gures, Reves et al predicted that, by the year 2010, there would be 11.8 anaesthesiologists per 100 000 US population, an increase from the 9.2 per 100 000 of 1996. Most managed care organizations employ between3.6 and 9.0 anaesthesiologists per 100 000 population. This managed care model predicts the need for 0±800 anaesthesia residents per year to meet future needs. However, this may underestimate the requirement for anaesthesiologists. They noted that not all of the citizens in the United States will be members of managed care organizations in the future because such organizations will have an uneven, regional distribution. Futhermore, managed care organizations generally cover a relatively young, employed segment of the population who are not as likely to require speciality care ± a very di€erent population from that covered by Medicare. Their forum also reviewed the Abt report and model. Using all the reports, analyses and predictions available to them, Reves et al believed that a reasonable scenario was the ®rst team model from the Abt study, with anaesthesiologists working 62 hours per week with retirement age at 65. That model predicts 500±600 anaesthesia residents per year to meet the needs in 2010 in the USA. Reves et al then discussed the means necessary to reduce the number of anaesthesia residents in the USA from 1800 per year to 500±600 per year. They listed involuntary methods which included limiting resident numbers through withdrawal of Medicare dollars to hospitals for graduate medical education anaesthesia and reducing the number of visas issued to international medical graduates. They did note that involuntary rather than voluntary methods would make it more dicult to adjust if over-correction in the

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number of anaesthesiologists were to occur in the future. If anaesthesia organizations such as the American Society of Anesthesiologists, the Society for Academic Anesthesia Chairmen, or the Residency Review Committee were to attempt to limit the number of trainees there would be the factor of federal antitrust violations. With the reduction in the number of anaesthesia residents, the replacement costs for other anaesthesia personnel could produce a tremendous ®nancial hardship for many hospitals, or cause them to close. Their report stressed a voluntary reduction in the number of residents and closure of the weakest training programmes. Reves et al then went on to address ways for academic centres to satisfy service requirements with a reduced number of trainees. They proposed maximizing eciency in the operating rooms and having nonphysicians (nurse anaesthetists, faculty and fellows) more involved in patient care. This thorough report by leaders in the ®eld of academic anaesthesiology analysed primarily economic factors and neither addressed quality of care nor predicted the future scope of practice of anaesthesiology.20 The legislature in the State of Minnesota mandated a study of anaesthesia practices in that state in 1994. The Commissioner of Health was asked to report to the legislature on anaesthesia services provided in health care facilities by physicians and nurse anaesthetists throughout Minnesota. To be included was a comparison of di€erent third-party reimbursement practices and contractual employment arrangements with regard to: 1. patient outcomes, including the incidence of morbidity and mortality; 2. the cost of services provided under each arrangement; 3. the e€ect of competition on each arrangement. The study was requested as a result of concerns over the rapidly changing market for anaesthesia services in Minnesota. Many hospitals in Minnesota had found it more ecient to contract for anaesthesia services with independent provider groups of anaesthesiologists than to keep nurse anaesthetists on their sta€ in salaried positions. Abenstein and Warner from the Mayo Clinic in Minnesota published an article in 1996 which is the summary version of the report to the Minnesota legislature.21 The authors state that the article relates to policy making and is not a scienti®c article or review. They reviewed and discussed anaesthesia services, patient outcomes and anaesthesia care providers and the cost indications of anaesthesia care in Minnesota. Their conclusions stated that anaesthesiology is a complex, medical discipline requiring constant vigilance of well-trained and experienced professionals. They further concluded that the anaesthesia care team is the safest and most e€ective mode of anaesthesia delivery. Accompanying the article were editorials; subsequent letters to the editor disagreed with the conclusions regarding the anaesthesia care team. Some argued that there is no creditable evidence for supporting the care team approach over physician anaesthesia with regard to outcome, cost, or patient reference while others emphasize the role of nurse anaesthetists in anaesthesia care.22±29 In 1990, workforce predictions were prepared for nurse anaesthetists for the year 2010. In 1967 there were two certi®ed registered nurse anaesthetists for every anaesthesiologist in the United States. Today these numbers are equal. The report by Cromwell et al used two methods to predict the number of nurse anaesthetists needed from 1993 to 2010. The ®rst scenario used a model of anaesthesia care with 60% in the anaesthesia care team mode with one anaesthesiologist supervising two nurse anaesthetists, 30% of anaesthesia care by an anaesthesiologist alone at 10% by an unsupervised nurse anaesthetist. The second hypothetical scenario used a model with

Human resource needs in the USA 431

a nurse anaesthetist involved in every anaesthetic given in the country. The ®rst, conservative approach estimated a shortage of 5756 nurse anaesthetists by 1990 and a shortage three times that number by 2010. The second model predicted an even greater shortage, with the need to double the total of nurse anaesthetists by the year 2010.30,31 COMPARISON OF ANAESTHESIOLOGISTS AND NURSE ANAESTHETISTS Geographical di€erences In the USA anaesthesiologists are located primarily in metropolitan areas along both coasts and in the large cities in the upper Midwest near the Great Lakes where hospitals, operating rooms and surgeons are located.32±34 There is an average of one anaesthesiologist for every 10 000 people in the United States. The geographical distribution of anaesthesiologists is similar to other groups of physician specialists in the country. In 1983 Orkin reported that anaesthesia in the Paci®c region of the States was delivered primarily by anaesthesiologists. Similarly, in the mountain states anaesthesiologists delivered most of the anaesthetic care. In general, the care team approach was to predominate throughout the rest of the country. In the remote areas, primarily in the Midwest, nurse anaesthetists were supervised by surgeons. Ninetyone percent of the anaesthetics administered in the United States were given by an anaesthesiologist or by a nurse anaesthetist supervised by an anaesthesiologist. The remaining anaesthetics were provided by nurse anaesthetists supervised by surgeons, occurring usually in small hospitals which scheduled few surgical cases. They were predominantly shorter and less complex surgical procedures for healthier patients.34±36 Today, anaesthesiologists are still primarily located in metropolitan and adjacent areas, with a distribution pattern very similar to that in 1980. There has been an almost two-fold increase in the number of anaesthesiologists since then, with an expansion in the number engaged in the subspeciality areas of cardiac, paediatric, neuro- and obstetric anaesthesia as well as pain management, intensive care etc. Along with the increasing number of anaesthesiologists there has been an improvement in access to care. Over the last 20 years smaller hospitals (fewer than 200 beds) in smaller communities have gained anaesthesiologists. The majority of hospitals with more than 100 beds, and hospitals in or near metropolitan areas, have at least one anaesthesiologist. Less than half of the hospitals in remote areas with fewer than 100 beds now have an anaesthesiologist.32±34 Today, nurse anaesthetists in the USA are distributed geographically very similarly to anaesthesiologists. Ninety-®ve percent of nurse anaesthetists practise in metropolitan or surrounding communities. Eighty-®ve percent are in secondary or tertiary health care centres.8,37 Although there is debate38, speculated di€erences in access to care to either an anaesthesiologist or a nurse anaesthetist in rural areas or other ostensibly under-served places cannot be substantiated by published data. There is no evidence of demand by patients in rural or under-served areas for anaesthesia practice models that di€er from those in larger cities. Cost di€erences The cost of medical care has risen as more complex surgery is performed on older, sicker patients along with improved outcome. Anaesthesia services comprise

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approximately 4% of health care expenditures in the USA. A few reports of di€erences in cost among anaesthesia providers do exist. The Abstein and Warner report described two models of cost comparing anaesthesiologists and nurse anaesthetists modi®ed from an issue of the New York State Society of Anesthesiologist Newsletter in 1994.21 Their analysis demonstrated the potential cost di€erence of anaesthesiologists compared to nurse anaesthetists by studying the increased medical expenses that occur with fragmentation of care that may occur with the triage and screening of sicker patients. They used examples of the di€erence of total billing allowed by Medicare in the preoperative setting for two hypothetical patients. The ®rst example totalled the cost allowed by Medicare for anaesthesia care for an otherwise healthy patient who is scheduled for a resection of the colon. With an anaesthesiologist involved the preoperative medical evaluation of the patient would be included in the charges to the patient from the anaesthesiologist. With a nurse anaesthetist involved without an anaesthesiologist there would be additional charges to the patient from the internist or general practitioner for pre-operative evaluation of the patient. The second example described a colon resection for a patient with signi®cant pulmonary or cardiac disease. With only a nurse anaesthetist involved additional charges accrued from pre-operative assessment and interpretation of pulmonary function tests and arterial blood gases. Furthermore, Abenstein and Warner cited charges to the patient for the placement of a pulmonary artery catheter and pre-operative optimization of congestive heart failure by an internist. With an anaesthesiologist involved a saving of almost 60% accrued in the second case. Their examples demonstrated the ability of anaesthesiologists to diagnose and treat patient's not only creating higher quality of care, but also leading to savings in the cost of pre-operative preparation. In another study, Johnstone analysed the average market price of the service of an anaesthesiologist ($133.00 per hour) and of a nurse anaesthetist ($86.00 per hour) by negotiating with seven large locum tenens agencies.39 Data derived in the study represent the total cost of short-term employment of anaesthesia providers ± which is considerably greater than the yearly salaries of most anaesthesia practitioners. A locum tenens agency received about 18% of the charges of either an anaesthesiologist or a nurse anaesthetist. The ®gures do show a 55% saving with the employment of unsupervised nurse anaesthetists. Using Johnstone's ®gures, the supervision ratio of nurse anaesthetists would need to be consistently 1:3 or greater to produce a saving in charges for anaesthesia services. The average yearly income of an anaesthesiologist is about $220 000 US, as reported by the American Medical Association.40 The average yearly income of a nurse anaesthetist in the USA is approximately $80 000±90 000 dollars.41 Figures from the American Medical Association, the American Society of Anesthesiologists, the Abt study and the American Association of Nurse Anesthetists show that an anaesthesiologist works an average of 60±65 hours per week and that a nurse anaesthetist works an average of 35±40 per week. Using these data, a supervision ratio of one anaesthesiologist to three nurse anaesthetists would be necessary to be cost e€ective using an analysis similar to that of Johnstone. This is all predicated on the regular use of operating rooms and other anaesthetizing locations in a multiple of three, with patients and surgical procedures that are appropriate. If the ®nancial reimbursement of anaesthesiologists and nurse anaesthetists were to alter then obviously the above analysis would need to be re-thought.42± 45 For example, a trend of narrowing salaries between anaesthesiologists and nurse anaesthetists, and rising malpractice costs for nurse anaesthetists, prompted changes in stang scenarios in Minnesota. Regardless, the above analyses account for neither safety issues nor patient preferences and currently there is no creditable or convincing evidence that any model of anaesthesia care reduces cost on a comprehensive basis.

Human resource needs in the USA 433

Di€erences in patient safety The improvement in patient outcome after anaesthesia has increased at the same rate as the increase in the number of anaesthesiologists (Figure 3). Beecher and Todd reported a study of death associated with anaesthesia surgery in 195446, and since then the number of anaesthesiologists has increased sixfold with a similar improvement in patient safety. Malpractice premiums for anaesthesiologists in the United States have dropped by one fourth over the past 10 years. Concurrently, those nurse anaesthetists who practise with less supervision have seen an increase in the cost of malpractice insurance. The increase in safety and better outcome from anaesthesia began with the increasing number of anaesthesiologists and was strengthened by the development of monitoring standards and patient safety policies developed by anaesthesiologists over the last 60 years. Signi®cant measures of quality and outcome, such as morbidity and mortality, are consequences of physician care and should be measured by medical analysis. However, the current diculty, as in the past, is in delineating and separating all the factors a€ecting anaesthesia care ± such as type of surgery, age of patient, concurrent disease and anaesthesia that may contribute to adverse outcome. In 1981 a study from North Carolina looked at anaesthesia mortality.47 The study from the State Medical Examiner investigated over two million administrations of anaesthetic. The report analysed all deaths after anaesthesia from 1969±1976. Ninety of the 900 post-operative deaths appeared to be related to anaesthesia care. Approximately 50% of the anaesthetics had been administered by nurse anaesthetists medically directed by a surgeon, while the

Figure 3. Relationship of the number of anaesthesiologists to anaesthesia-related mortality. ASA ˆ American Society of Anesthesiologists. Modi®ed with permission from the American Society of Anesthesiologists.

434 J. R. Moyers

remaining 50% were administered by an anaesthesiologist or by a nurse anaesthetist supervised by an anaesthesiologist. The highest mortality rate was in the group anaesthetized by a nurse anaesthetist medically directed by a surgeon. The smallest number of anaesthetic-related deaths were in the group anaesthetized by a nurse supervised by an anaesthesiologist, while the third group with an anaesthesiologist working alone was intermediate in mortality. No statistically signi®cant conclusions could be drawn from the study because there was no statistical analysis provided for the results. Further, there were no adjustments made for patient co-existing disease, patient age, ASA classi®cation, type of surgery or elective or emergent nature of the surgery. Some argue that the patients in the study cared for by anaesthesiologists were older, sicker patients undergoing more complex surgical procedures, while those anaesthetized by nurse anaesthetists without an anaesthesiologist were more likely to be a healthier group of patients undergoing more straightforward surgery. A study from the Stanford Center for Health Research was done in the same era. The investigators performed a comparison of patient data gathered from medical centres where anaesthesia was provided either primarily by anaesthesiologists or primarily by nurse anaesthetists. The ®gures were obtained prospectively over a 10month period from 1973 to 1974 involving 8593 patients undergoing 15 di€erent surgical procedures. A weighted number was assigned to each patient, depending upon severity of disease and the prospect of developing post-operative morbidity or of postoperative mortality. Actual patient outcome was compared with the predictions from the patient's health status and operative procedure. Despite fewer than 10 000 patients comprising the study, it found that mortality and severe morbidity was 11% higher than predicted for patients who received anaesthesia care from a nurse anaesthetist, 3% lower than that predicted for patients who received care from an anaesthesiologist and 20% lower than that predicted for patients who received anaesthesia from a nurse anaesthetist supervised by an anaesthesiologist. While the data favour hospitals with anaesthesiologists compared to hospitals with nurse anaesthetists, there was no statistically signi®cant di€erence among the groups of patients, possibly due to the small number in the study. Further limitations of the report include data based on clinical care provided more than 20 years ago for patients who were not randomly allocated to either an anaesthesiologist or to a nurse anaesthetist.48 Silber et al recently studied post-operative adverse outcome and failure to rescue from adverse events, analysing hospital and patient characteristics associated with death after surgery.49 The report investigated hospital and patient factors associated with postoperative deaths in the study of 5972 Medicare patients. The authors reviewed two major surgical procedures: 3141 transurethral resections of the prostate and 2831 cholecystectomies. The patients and procedures were randomly selected from 531 hospitals in seven di€erent states. They did stratify patient severity of illness in the study using the MedisGroups severity score and severity of illness, as well as using di€erences among hospital characteristics. Their data were analysed for correlation with mortality, complications and failure to rescue from adverse events. Not surprisingly, adverse events related primarily to the underlying disease of the patients. Failure to rescue (prevent death after an adverse outcome) was, however, inversely associated with the proportion of board-certi®ed anaesthesiologists on the sta€ at each hospital, as was the death rate. Stated simply, improved patient outcome was associated with an increased number of board-certi®ed anaesthesiologists on a hospital sta€. In another study Keenan and colleagues investigated bradycardia during anaesthesia in patients from birth to 4 years of age.50 They analysed 7979 records from infants undergoing non-cardiac surgery, examining the incidence of interoperative bradycardia. The authors concluded that

Human resource needs in the USA 435

bradycardia occurred more frequently in infants undergoing anaesthesia compared to older children, and that it was associated with substantial morbidity. Slowing of the heart rate was more likely to occur in sicker infants undergoing prolonged surgery and less frequently when a paediatric anaesthesiologist was present. A study on maternal mortality done in the United Kingdom between 1989 and 1990 reported fewer deaths in hospitals with board-certi®ed anaesthesiologists on the medical sta€.51 The previous three studies do not include speci®c information on nurse anaesthetists but do lend credence to the notion that advanced training leads to improvement in the quality of patient outcome. An outcome study performed at the Massachusetts General Hospital looked at three models of anaesthesia care delivery: care by an anaesthesiologist, care by an anaesthesiologist with a resident, and care by an anaesthesiologist with a nurse anaesthetist. They found improved patient outcome with senior anaesthesiologists, but no other di€erences among the three models. The investigators adjusted only partially for case mix, and anaesthesiologists were involved in the care for patients of all three groups.52 The US Centers for Disease Control at one time contemplated, but never completed, a national study of mortality and morbidity associated with anaesthesia. Although viewed as an important issue, the infrequent occurrence of severe morbidity and mortality, which would have required many patients from many hospitals, made the study prohibitively expensive. Furthermore, randomization of patients to either an anaesthesiologist, an anaesthesiologist and a nurse anaesthetist or an unsupervised nurse anaesthetist presented an ethical dilemma and an organizational problem. If such a study were to be done, the complex surgical procedures on sicker, older patients could not be sent only to centres with anaesthesiologists.53,54 Quality is dicult to measure in any profession but has always been closely related to education. Many experts believe that common sense and evidence dictate that nurse anaesthetists are not educated to provide quality, independent anaesthesia care for the broad spectrum of patient needs. They view anaesthesia as the practice of medicine and an intellectual process, not only a technical skill. Further, anaesthesiologists are recognized as having cognitive and technical skills shaped by a unique educational process and experience forming a foundation of clinical knowledge used perioperatively for all patients in all venues of anaesthesia care. Not to have anaesthesiologists involved in anaesthesia care could lead to two levels of service and an increased risk to patients.55 FUTURE OF HUMAN RESOURCES IN ANAESTHESIOLOGY Predictions for the future needs of human resources in anaesthesia in the United States are dicult because both physicians and non-physicians may provide service. Di€erences in education, training, skilful practice and future remuneration make estimates particularly dicult. The wide variations in predicted workforce, and the reasons explaining it with regard to surgical anaesthesia, have been discussed earlier in the chapter. Currently, in the USA, there are approximately 28 million surgical and other procedures requiring anaesthesia care each year. They are continuing to increase in complexity and involve older patients with more debilitating co-existing diseases. Over the next 30 years, non-cardiac surgery in patients older than 65 will increase from 7 million procedures per year to over 14 million procedures per year, with a total number of surgical procedures per year increasing to more than 40 million by the year 2025.18,56 The guidelines of the American Society of Anesthesiologists declare that anaesthesiology is the practice of medicine and that an anaesthesiologist should be personally responsible for each patient and for all aspects of anaesthesia care.

436 J. R. Moyers

The guidelines further state that other related activities, such as regional anaesthesia and the use and interpretation of invasive monitors, such as the pulmonary artery catheter and the transoesophageal echocardiogram, should be done only by a properly trained physician. If the federal government of the United States continues with its present policies, anaesthesiologists will continue to be involved in all anaesthetic care. Conversely, if that policy changes, and future patients do not gain (or want) access to anaesthesiologists, the concept of the anaesthesia care team fades and nurse anaesthetists practise independently, the need for anaesthesiologists will be very di€erent.57±60 With regard to obstetric anaesthesia, the birth rate in the USA is expected to increase by only 3% over the next 15 years. The Abt used two models to estimate the number of full-time equivalent anaesthesiologists needed for obstetric anaesthesia care for the year 2010. Their ®rst predication used a facility-based scenario. It included nurse anaesthetists in obstetric anaesthesia care and predicted that smaller institutions would be delivering fewer babies in the future. By using the model, the report predicted that between 1200 and 1700 full-time equivalent anaesthesiologists would be necessary in 2010 for obstetric anaesthesia care.18 The second model using total anaesthesia time for obstetric anaesthesia estimated that between 800 and 1510 anaesthesiologists would be needed in 2010 for obstetric anaesthesia care. Currently, there are about 2000 full-time equivalent anaesthesiologists involved in obstetric care. A survey by Hawkins and colleagues characterized the changing nature of the obstetric anaesthesia workforce from 1981 to 1992.61 The study found that, in 1981, 70% of all anaesthetics for Caesarean delivery involved an anaesthesiologist. Thirty percent of all anaesthetics for Caesarean section were administered by an obstetrician or a nurse anaesthetist practising independently. Further, for labour and vaginal delivery, only 20% of parturients had an anaesthetic with an anaesthesiologist involved. By 1992, Hawkins et al found that analgesia was used more often during labour and that regional anaesthesia, when compared to general anaesthesia, was used more frequently for Caesarean section. In larger hospitals, with more than 500 births per year, an anaesthesiologist was involved in 88±96% of Caesarean deliveries and between 79 and 95% of labour analgesia. Also in the 1992 survey, hospitals with fewer than 500 births had reduced availability of regional anaesthesia for labour and delivery. Just over 40% of all anaesthetics for labour and Caesarian delivery involved an anaesthesiologist in the small hospital. The joint statement from the American Society of Anesthesiologists and the American College of Obstetricians and Gynecologists stated that there should be `appointment of a quali®ed anesthesiologist to be responsible for all anesthetics administered'. It further states `the administration of general or regional anesthesia requires numerous medical judgements and technical skills. Nurse anesthetists are not trained as physicians and cannot be expected to make medical decisions. Obstetricians seldom have sucient training or experience in anesthesia to allow them to properly supervise nurse anesthetists'.62 If these guidelines are followed, and regionalization of obstetric care to larger medical centres is included in the study, the number of anaesthesiologists in obstetric care would be predicted to increase slightly. In 1992 data from the American Society of Anesthesiologists showed that less than 5% of anaesthesiologists' professional time was involved in pain management. This study indicated approximately 1200 full-time equivalent anaesthesiologists involved in pain care. The need for anaesthesiologists devoted to chronic and acute pain management is predicted to double by the year 2010. The survey predicted that chronic pain management would grow at the same rate as the overall population, but e€ort involved in acute pain management (non-obstetric) would grow to 10% of total anaesthesia time. A needs-based approach estimated 2800 full-time equivalent for pain management in the

Human resource needs in the USA 437

year 2010. A facilities-based approach predicted between 1650 and 1951 full-time anaesthesiologists involved in acute and chronic pain management in the year 2010. Today, some prognosticators forecast that these predictions underestimate grossly the need for anaesthesiologists involved in acute and chronic pain management in the future. Although the contributions are very important, the actual numbers of full-time anaesthesiologists involved in research, intensive care and administration are small and most likely will be so in the future. Both facilities-based and time-based predictions for full-time anaesthesiologists practising critical care were expected to increase from 680 in 1992 to 780 by the year 2010 according to the Abt data. Currently only 7% of anaesthesiologists in the United States spend more than 10% of their time in research activities. The Abt study predicted that the anaesthesiologist full-time equivalent in research would increase from 381 in 1992 to 684 in 2010. They also predicted the fulltime equivalent anaesthesiologist in administration would have doubled to 1566 by the year 2010.18 In the future, anaesthesiologists will become more involved in pre-operative evaluation and preparation of surgical patients. This is an attempt to reduce cancellations and cost. A perioperative screening clinic directed by an anaesthesiologist can reduce preoperative medical consultation by threefold.63,64 In one study the reduction and cancellation rate due to unresolved laboratory abnormalities or medical problems was reduced by 88% and the cost of laboratory tests was reduced by 59% or by $112.00 per patient. Unnecessary pre-operative laboratory testing leads to excessive health care and may result in additional excess morbidity. Meta-analysis studies of pre-operative chest radiographs obtained in the absence of speci®c indications show that false-positive results leading to invasive procedures and associated morbidity were more frequent than the discovery of new ®ndings which led to a change in management.65 Many studies have demonstrated that screening laboratory tests rarely uncover unexpected or abnormal ®ndings and infrequently lead to changes in care and improved outcome. Narr and colleagues argue that there is little reason for performing screening tests in low-risk, asymptomatic patients. Tests should be reserved for indications found on history or physical examination.64±66

CONCLUSIONS Because of market forces and some changes in public policy and health care reform, employment opportunities for anaesthesia residents became more prevalent in 1995. A report by Miller and associates showed that the unemployment rate for anaesthesia residents ®nishing training in 1995 was 1.1%, which was lower than the rate for pathology, paediatrics or internal medicine subspeciality residents.67 An analysis of the trends classi®ed in the major anaesthesia journals shows an increase in the number of employment opportunities for anaesthesiologists (Figure 4). It appears that there has been an over-correction in the system; the possibility of employment opportunities foreseen in the early 1990s never materialized so that there are now not enough graduates in training programmes to ®ll all the positions that are open. With the current practice models, anaesthesiology workforce in the future will be adequate with the 1000±1200 trainees per year. In the end, future human resources in anaesthesiology will be dependent upon economic forces, political in¯uences and those whom anaesthesiologists and hospitals employ to provide anaesthesia care.68

0

20

40

60

80

100

120

140

1993

1994

1995

1996 Year

1997

1998

1999

2000

positions wanted

total positions

academic positions

Figure 4. The average monthly numbers of classi®ed data advertisements in Anesthesiology, 1993±2000, are displayed for total employment opportunities and vacancies in academic positions; also shown are the numbers of advertisements from anaesthesiologists seeking employment.

Number

160

Classified advertising in Anesthesiology 1993-2000 (monthly average)

438 J. R. Moyers

Human resource needs in the USA 439

Research agenda . what are the best predictors of future human resource needs in anaesthesia? . which workforce model of anaesthesia care delivery provides the highest quality and safest care? The most cost-e€ective?

Acknowledgement The author thanks Joyce M. Jones for invaluable assistance in the preparation of this manuscript. REFERENCES 1. Calverley RK. In Barash PG et al (eds) Anesthesia as a Speciality: Past, Present, and Future in Clinical Anesthesia, 3rd edn, pp 3±28. Philadelphia: Lippincott-Raven, 1997. 2. Little DM Jr & Betcher AM. The Diamond Jubilee-1905±1980, p 8. Park Ridge, IL: American Society of Anesthesiologists, 1980. 3. Black EA & Deming PA. Anesthesiology research: a workshop report. Washington, DC: US Department of Health, Education, and Welfare, 1977. DHEW Pub. No. (NIH) 77±80. 4. Jolly P & Hudley DM. AAMC data book: statistical information related to medical education. Washington, DC: Association of American Medical Colleges. January 1994; Tables A1 and B1. 5. Roback G, Randolph L, Seidman B & Pasko T. Physician characteristics and distribution in the US. Chicago American Medical Association 1994, 1994. Table A-3. 6. Anders G. Once hot specialty, anesthesiology cools as insurers scale back. Wall Street Journal 1995; A1. March 17. 7. Orkin FK. Work force planning for anesthesia care. International Anesthesiology Clinics 1995; 33: 69±101. 8. Fallacaro MD, Obst TE, Gunn IP & Chu M. The national distribution of certi®ed registered nurse anesthetists across metropolitan and nonmetropolitan settings. Journal of the American Association of Nurse Anesthetists 1996; 64: 237±242. * 9. Gravenstein JS, Steinhaus JE & Volpitto PP. Analysis of manpower in anesthesiology. Anesthesiology 1970; 33: 350±357. *10. Summary Report of the Graduate Medical Education National Advisory Committee, vol. 1, DHEW Pub. No. (HRA) 81±651. Washington, DC: Oce of Graduate Medical Education, Health Resources Administration, US Department of Health, Education, and Welfare, 1980. September. 11. Bowman MA, Katzo€ JM, Garrison LP Jr & Willis J. Estimates of physician requirements for 1990 for the specialties of neurology, anesthesiology, nuclear medicine, pathology, physical medicine and rehabilitation, and radiology. Journal of the American Medical Association 1983; 250: 2624±2627. 12. Eisenberg JM. Doctors' Decisions and the Cost of Medical Care, pp 38±49. Ann Arbor, MI: Health Administration Press, 1986. 13. Bindman AB. Primary and managed care. Ingredients for health care reform. Western Journal of Medicine 1994; 161: 78±82. 14. Schwartz A, Ginsburg PB & LeRoy LB. Reforming graduate medical education. Journal of the American Medical Association 1993; 270: 1079±1082. 15. Rivo ML, Jackson DM & Clare FL. Comparing physician workforce reform recommendations. Journal of the American Medical Association 1993; 270: 1083±1084. *16. Reves JG, Rogers MC & Smith LR. Resident workforce in a time of U.S. health-care system transition. Anesthesiology 1996; 84: 700±711. 17. Weiner JP. Forecasting the e€ects of health reform on US physician workforce requirement. Evidence from HMO stang patterns. Journal of the American Medical Association 1994; 272: 222±230. *18. Abt Associates. Estimation of physician workforce requirements in anesthesiology. Bethesda, Park Ridge, MD, IL: American Society of Anesthesiologists, 1994. 19. Buchwald IP. Correspondence. Anesthesiology 1996; 85: 945. 20. Longnecker DE. Editorial view. Anesthesiology 1996; 84: 495±497. *21. Abenstein JP & Warner MA. Anesthesia providers, patient outcomes, and costs. Anesthesia and Analgesia 1996; 82: 1273±1283. 22. Hanna K. Letter to the Editor. Anesthesia and Analgesia 1996; 83: 1347±1350.

440 J. R. Moyers 23. 24. 25. 26. 27. 28. *29. 30. 31. 32. 33. *34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. *49. 50. 51. 52. 53. 54.

Kremer M. Letter to the Editor. Anesthesia and Analgesia 1996; 83: 1347±1350. Stoelting RK. Letter to the Editor. Anesthesia and Analgesia 1996; 83: 1347±1350. Gaba DM. Letter to the Editor. Anesthesia and Analgesia 1996; 83: 1347±1350. Owens WD. Nonphysician clinicians in the health care workforce (letters). Journal of the American Medical Association 1999; 28: 509±511. Cooper RA, Henderson T & Dietrich CL. Roles of nonphysician clinicians as autonomous providers of patient care. Journal of the American Medical Association 1998; 280: 795±802. Grumbach K & Co€man J. Physicians and nonphysician clinicians: complements or competitors? Journal of the American Medical Association 1998; 280: 825±826. Reves JG & Greene NM. Anesthesiology and the Academic Medical Center. Place and promise at the start of the new millenium. International Anesthesiology Clinics 2000; 38: 1±179. Cromwell J, Rosenbach ML, Pope GC et al. CRNA (certi®ed registered nurse anesthetist) manpower forecasts: 1990±2010. Medical Care 1991; 29: 628±644. Rosenbach ML, Cromwell J, Pope GC et al. Report of the National Commission on Nurse Anesthesia Education. Study of nurse anesthesia manpower needs. AANA Journal 1991; 59: 233±240. Orkin FK. The Geographical Distribution of Anesthesia Care Providers in the United States. Park Ridge, IL: American Society of Anesthesiologists, 1983. Schwartz WB, Newhouse JP, Bennett BW et al. The changing geographic distribution of board-certi®ed physicians. New England Journal of Medicine 1980; 303: 1032±1038. Orkin FK. The geographic distribution of anesthesiologists during rapid growth in their supply. Anesthesiology 1994; 81: A1295. Fallacaro MD. An inecient mix: a comparative analysis of nurse and physician anesthesia providers across New York State. Journal of the New York State Nurses Association 1998; 29: 4±8. Dunbar PJ, Mayer JD, Fordyce MA et al. Availability of anesthesia personnel in rural Washington and Montana. Anesthesiology 1998; 88: 800±803. Szigeti E, Largent RN & Eberhardt BJ. An exploratory study of the correlates of intent to quit among certi®ed registered nurse anesthetists in North Dakota. Journal of Rural Health 1990; 6: 317±327. Gunn IP. Rural health care and the nurse anesthetist. Clinical Forum for Nurse Anesthetists 2000; 11: 77±86. Johnstone RE. Market costs of short-term physician and nurse anesthesia services. Journal of Clinical Anesthesia 1994; 6: 129±132. Socioeconomic Characteristics of Medical Practice 1993. Center for Health Policy Research. Chicago: American Medical Association, 1993, publication OP 192693. Garde JF. The nurse anesthesia profession. A past, present, and future perspective. Nursing Clinics of North America 1996; 31: 567±580. Cromwell J & Snyder K. Alternative cost-e€ective anesthesia care teams. Nursing Economics 2000; 18: 185±193. Cromwell J. Barriers to achieving a cost-e€ective workforce mix: lessons from anesthesiology. Journal of Health Politics, Policy & Law 1999; 24: 133±161. Gunn IP. Health care delivery and change: thoughts on Lema's `. . . of dinosaurs, dodos and anesthesia personnel'. Clinical Forum for Nurse Anesthetists 1999; 10: 191±196. Glance LG. The cost e€ectiveness of anesthesia workforce models: a simulation approach using decisionanalysis modeling. Anesthesia and Analgesia 2000; 90: 584±592. Beecher HK & Todd DP. A study of the deaths associated with anesthesia and surgery. Annals of Surgery 1954; 140: 2. Bechtoldt AA Jr. Committee on anesthesia study of anesthetic-related deaths: 1969±1976. North Carolina Medical Journal 1981; 2: 253±258. Forrest WH Jr. Outcome ± the e€ect of the provider. In Hirsh RA, Forrest WH Jr, Orkin FK & Wollman H (eds) Health Care Delivery in Anesthesia, pp 137±142. Philadelphia: George F. Stickley, 1980. Silber JH, Williams SV, Krakauer H & Schwartz JS. Hospital and patient characteristics associated with death after surgery: a study of adverse occurrence and failure to rescue. Medical Care 1992; 30: 615±629. Keenan RL, Shapiro JH, Kane FR & Simpson PM. Bradycardia during anesthesia in infants. Anesthesiology 1994; 80: 976±982. Hibbard BM, Anderson MM, Drife JO et al. Report on con®dential enquiries into maternal deaths in the United Kingdom 1988±1990, pp 80±96. London: Her Majesty's Stationery Ocer, 1994. Gilbert J. Outcome-experience and training of the anesthetist. In Hirsh RA, Forrest WH Jr, Orkin FK & Wollman H (eds) Health Care Delivery in Anesthesia, pp 143±150. Philadelphia: George F. Stickley, 1980. Klaucke DN, Revicki DA & Brown RE. Investigation of mortality and severe morbidity associated with anesthesia: Pilot study. Final report. Atlanta and Washington, DC: Centers for Disease Control and Battelle Human A€airs Research Centers, 1988 December. Orkin FK. Patient outcome following anesthesia care. Role of the provider. Problems in Anesthesia 1992; 6: 212±227.

Human resource needs in the USA 441 *55. Bristow LR. Economic and quality of care issues with implications on scope of practice ± physicians and nurses. Report of the Board of Trustees. American Medical Association, 1993. 56. Mangano DT. Preoperative risk assessment: many studies, few solutions: is a cardiac risk assessment paradigm possible? Anesthesiology 1995; 83: 897±901. 57. Stoelting RK. Past, present, and future of anesthesiology (Guest Editorial). American Journal of Anesthesia 1996; 23: 219±220. 58. McFadden P. Statement of the American Associate of Nurse Anesthetists before the Physician Payment Review Commission regarding payment to the anesthesia care team, 1995. January 21. 59. Plitt KC. Testimony on behalf of the American Association of Nurse Anesthetists before the House Ways and Means Subcommittee on Health, 1995. July 25. 60. McKay G. Transcript of responses to Judiciary Committee on March 5, 1996. 61. Hawkins JL, Gibbs CP, Orleans M et al. Obstetric anesthesia work force survey, 1981 versus 1992. Anesthesiology 1997; 87: 135±143. 62. Optimal Goals for Anesthesia Care in Obstetrics. Park Ridge, IL: American Society of Anesthesiologists, 1997. 63. Wiklund RA & Rosenbaum SH. Anesthesiology. New England Journal of Medicine 1997; 337: 1132±1141. 64. Fischer SP. Development and e€ectiveness of an anesthesia preoperative evaluation clinic in a teaching hospital. Anesthesiology 1996; 85: 196±206. 65. Archer C, Levy AR & McGregor M. Value of routine preoperative chest x-rays: a meta-analysis. Canadian Journal of Anaesthesia 1993; 40: 1022±1027. 66. Narr BJ, Hansen TR & Warner MA. Preoperative laboratory screening in healthy Mayo patients: coste€ective climination of tests and unchanges outcomes. Mayo Clinic Proceedings 1991; 66: 155±159. 67. Miller RS, Dunn MR & Whitcomb MB. Initial employment status of resident physicians completing training in 1995. Journal of the American Medical Association 1997; 277: 1699±1704. *68. Moyers JR. Workforce in anesthesiology. Problems in Anesthesia 1998; 10: 337±350.