Anesthesia Providers, Patient Outcomes, and Costs

In the MinnesotaCare Bill of 1994, the legislature required a study of anesthesia practices Article 8, Section 69. In this study, the Commissioner of Health was to report to the legislature on anesthesia services provided in health care facilities in Minnesota by physicians and nurse anesthetists. To be included in this study was a comparison of different third-party reimbursement practices and contractual and employment arrangements in regard to: 1. Patient outcomes in Minnesota, including the incidence of morbidity and mortality as related to provider and practice methods, in urban and rural settings. This information should be found in the scientific literature. 2. The cost of the service provided under each arrangement. 3. The effects on competition under each arrangement. The study was authorized as a result of concerns over the rapidly changing market for anesthesia services in Minnesota; specifically, Minnesota hospitals found it more efficient to contract for anesthesia services with independent provider groups than to keep nurse anesthetists on staff in salaried positions. The following report is an abridged version of a document submitted by the Minnesota Society of Anesthesiologists to the Minnesota Commissioner of Health. The original report has been modified to present a national, not statewide, perspective on anesthesia services. It presents a compilation of information that can be used by policy makers to aid future decisions on workforce size and composition, quality expectations, and costs for anesthesia services. Specifically, this monograph will describe who delivers anesthesia services in the United States, the delivery models used, associations between providers and patient outcomes, and the cost-effectiveness of various anesthesia providers and delivery models. The data characterizations and analyses presented herewithin represent our interpretations of mortality reports and outcome studies in which the type of anesthesia delivery model was a variable factor. Definition of Terms Providers of Anesthesia Services Anesthesiologists. Anesthesiologists are physicians who hold unrestricted medical licenses. Postsecondary education for anesthesiologists generally consists of at least four years of college or university training, four years of medical school, and four years of postgraduate medical training in an accredited anesthesiology residency program. Approximately one third of resident physicians choose to complete an additional year of subspecialty training in areas such as pain management, critical care medicine, neuroanesthesia, or cardiovascular, obstetrical, or pediatric anesthesia. Thus, anesthesiologists receive at least 12 years of postsecondary education. In Minnesota, 17% of current anesthesiology trainees hold nonmedical advanced degrees (e.g., master's and/or PhDs), and 13% have completed a residency in another medical specialty (e.g., internal medicine, pediatrics, family medicine) (unpublished survey, University of Minnesota and Mayo Graduate School of Medicine, 1995). The continuum of education in anesthesiology for medical school graduates consists of a year of general clinical experience (Clinical Base Year), commonly know as an internship. The second, third, and fourth postgraduate years (Clinical Anesthesia 1-3) are spent learning all aspects of clinical anesthesia, including subspecialty experiences in obstetrical, pediatric, cardiothoracic, and neurologic anesthesia; acute and chronic pain management; critical care medicine; and postanesthesia recovery room care. Anesthesiology residents train to be generalist physicians, with emphasis on perioperative medicine and pain management. These physicians are educated to diagnose and treat disease in all patients, no matter at what extreme of age or severity of disease. In many ways, anesthesiologists function as their patients' primary care physicians in the operating room, postanesthesia recovery room, and sometimes intensive care units--and even on the hospital ward during preoperative and postoperative evaluation and treatment including pain management. After successful completion of the residency, which includes a certificate of clinical competency, these physicians may voluntarily enter the examination system of the American Board of Anesthesiology (ABA). The ABA is an independent certifying organization and has been recognized by the American Board of Medical Specialties since 1941. The ABA defines anesthesiology as the practice of medicine. Specific practices and expectations of board-certified anesthesiologists are shown in Table 1 and Table 2, respectively. Booklet of information. Hartford, CT: American Board of Anesthesiology, 1994:1.Table 1: Practices of Board-Certified AnesthesiologistsTable 2: Expectations of Board-Certified AnesthesiologistsNurse Anesthetists. Nurse anesthetists are registered nurses who hold licenses limited to nursing. Postsecondary education for nurse anesthetists may involve four years of college or university, generally resulting in bachelor of science in nursing degrees. A minimum of one year of work experience as a staff nurse in a critical care setting (e.g., intensive care unit, neonatal unit, or postanesthesia recovery room) is required prior to entering nurse anesthesia schools. The educational experience of nurse anesthesia curricula usually lasts two years and consists of didactic instruction and supervised clinical experience in most areas of the operating and labor and delivery suites. Thus, nurse anesthetists receive less than half the postsecondary education and anesthesia training of physician anesthesiologists. Nearly all nurse anesthesia schools offer an elective master's degree program. After successful completion of nurse anesthesia school, graduate nurse anesthetists may voluntarily take a certification examination. Successful completion of the examination confers the title of "Certified Registered Nurse Anesthetist" (CRNA). The American Association of Nurse Anesthetists (AANA) is directly responsible for the accreditation of nurse anesthesia schools and for establishing criteria for certification as a nurse anesthetist. It is also the representative body for the profession 1. This consolidation of education program accreditation, individual certification of professional aptitude, and political functions by nurse anesthetists sharply contrasts with the unique functions of the Residency Review Committee for Anesthesiology of the Accreditation Council for Graduate Medical Education (ACGME), the ABA, and the American Society of Anesthesiologists (ASA). These three organizations serve the respective functions for anesthesiologists but are intentionally kept independent of each other. The strict independence of these functions prevents inappropriate influence of any one of them over the other. Unlike the activities of anesthesiologists, those of nurse anesthetists are usually confined to the operating room. In most states, nurse anesthetists must be supervised (medically directed) by a physician or other practitioner who is licensed to practice independently. That individual may be an anesthesiologist, surgeon, or other operative practitioner (e.g., radiologist or cardiologist). Although nurse anesthetists may discuss anesthesia risks with the patient, the responsibility and accountability for the conduct of anesthesia care remains with the practitioner licensed to practice independently. Harris v Miller, 1994 NC Lexis 16, 3 (NC 1994). Anesthesiologists' Assistants. Anesthesiologists' assistants are a relatively new class of health care providers. They are graduate physicians' assistants who have satisfactorily completed an approved anesthesiologists' assistant training program. Postsecondary education for anesthesiologists' assistants consists of four years of college or university, generally resulting in bachelor of science degrees in a premedical curriculum. After graduation, students enter a two- to four-year anesthesiologists' assistant curriculum, which is split between didactic and clinically based education. After successful completion of this training, they are eligible to take a national certification examination given by the National Commission on the Certification of Anesthesiologists' Assistants in collaboration with the National Board of Medical Examiners. Gupta G, ed. Allied health education directory. Chicago, IL: American Medical Association, 1993;21:25. The activities of an anesthesiologists' assistant are very similar to those of a nurse anesthetist. They work predominately in the operating room, assisting in the intraoperative care of patients. They work under the direct supervision (medical direction) of an anesthesiologist. They are recognized by the Health Care Financing Administration (HCFA) as equivalent to CRNAs for purposes of reimbursement under Medicare law. Rules and regulations. Federal Register. July 31, 1992;57:33879-96. Number and Types of Anesthesia Providers in the United States. Since the rapid growth in medical schools in the 1970s, the specialty has seen a steady growth in physician numbers. During the past two decades, there has been a marked shift in the relative proportions of the different anesthesia providers. While US medical school graduates increased from 8000 in 1967 to 15,000 in 1983, the rate of growth of residents who completed training in anesthesiology increased even faster. (5) In 1978, there were 2421 resident physicians in anesthesiology. In contrast, there were 4563 residents in anesthesiology in 1988. During the same period, the number of nurses enrolled in anesthesia school dropped from approximately 1200 to 600 2. Membership in the ASA has grown from 16,183 in 1978 to 32,992 in 1993 Figure 1. In July 1991, the AANA reported 24,681 members, including student anesthetists. While the number of active anesthesiologists has increased fourfold over the past two decades, the number of active nurse anesthetists has doubled. Most of that growth occurred in the period 1970-1985; since 1985, the number of active nurse anesthetists has been about the same. US Department of Health and Human Services. Sixth report to the President and Congress on the status of health care personnel in the US, 1988.Figure 1: Membership in the American Society of Anesthesiologists (ASA) from 1943 to 1993. Approximately 90% of all anesthesiologists are members of the ASA. From: ASA membership survey, December 31, 1993.Anesthesia Services The wide spectrum of health care facilities throughout the United States makes defining anesthesia services difficult. The range of anesthesia services within a health care facility is dependent on the depth and breath of the entire medical practice within the institution. Health care facilities range from comprehensive tertiary referral centers to small rural hospitals and outpatient surgical centers. Clearly, the surgical, medical, and anesthesia care needs in each of these facilities are distinctly different from each other. In most comprehensive medical environments, all types of anesthesia services are provided. These services are shown in Table 3. Not all of these services are needed in every health care facility. For example, an outpatient surgical center or chronic pain clinic would not be expected to provide obstetrical or critical care services to its patients, nor would 24 hour a day coverage be required. Whether all or a subset of anesthesia-related services is required by a health care facility is dependent on the and of the medical care Types of Anesthesia The of anesthesia are as as the health care facilities in which anesthesia services are provided. In of the service of anesthesia generally one of the following 1. every is by an 2. Nurse every is by a nurse under the medical of the operating practitioner 3. Anesthesia care the is by a resident or nurse or student nurse under the medical of an anesthesiologist. In these one or more physicians are present at critical during the are by an and the by the anesthesia care In anesthesiologists in practices to with medical anesthesia care practices usually have one or more physicians to to a and to in the of the facility. than 90% of the surgical in the United States at facilities are by an or the anesthesia care is by an and found that who are in rural in hospitals than with and with than four The facilities are more to be and less to be accredited by the Commission on Accreditation of In comparison with members of anesthesia care and CRNAs are with less and on Patient and Anesthesia Care with anesthesia and have been a primary of the medical specialty since the was reported in In this a been with and a of was the was found During the three of were to have to perioperative These are used patient and anesthesia The and is the different patient and that to This can be since are usually For example, a patient has disease. during the the in of intensive medical the patient on the operating it may be to the of the or the disease most to the that to the or and there is a rate of with surgical a of to be during the perioperative period The with as a of outcome is that the most of is severity of disease In the United it is that the of the to more than two of perioperative The report of a perioperative have been a number of mortality studies since The anesthesia from with in which the or to patients' range from 1 in to 1 in Table Since studies have a in and of perioperative a in rate of anesthesia-related from to over an During that same period, the morbidity rate from to less than In reported of or system in ASA status In and reported no in ASA status anesthesia and at Mayo years reported no in ASA status outpatient at the Mayo In this study, four within of two of postoperative and two in a or relative was the in this study all occurred at to or less than those expected for of similar age and who not anesthesia and mortality and morbidity in ASA status and Anesthesiology Since the studies of perioperative outcomes have the rate of the of these studies are to for a number of the of is there are for types of in a number of these and the of (e.g., or and the types of (e.g., referral are The reported in these studies range from about to Table evaluation of these studies that the at least that related to has been since the This may be to a of including intraoperative and preoperative as as increased and education of anesthesia personnel and For example, the of may have to the of perioperative a study by was to any in outcome with the of of During data a in patient outcomes during this in outcomes is by data from the ASA studies In these from to the of all to system from to 17% Figure 2. for from to and for from to Figure 3. These data that the rate of outcomes from anesthesia has in the It is to that this steady in outcomes reported in the ASA studies the of and other This in outcomes occurred at the same that the number of American physicians entering and from anesthesiology residency more than This in patient outcomes to be Committee on professional ASA 2: for system as a of all in the for each not the of as there are in the prior to or no is From: Committee on professional ASA for and as a of all in the for each between and From: Committee on professional ASA membership survey, December 31, 1993. Patient and Anesthesia Providers the for the in outcome is as as the of perioperative A number of have that new and are the for the marked in outcome studies of the of in more than were to a in patient outcome with the of that This work that of surgical (e.g., must be enrolled in studies to provide the needed to there are associations between perioperative or and various and practice models. of this size are and may be Review of the and health policy studies of anesthesia services that the in the number of physicians in the practice of anesthesiology is responsible for the in perioperative The for this was reported by in a study of more than two in from to The Anesthesia Committee reports of about perioperative and of these were These were by anesthesia provider the rate of was with the and the rate occurred in who care in nurse Table These are the in practice between each provider model are Nurse practices are predominately found in rural hospitals In these nurse anesthetists anesthesia to who are generally and less than those in and tertiary It would be expected that these would have outcomes, but in the study more they care in the nurse than in an The not provide of these of by Anesthesia were found in a study reported by the for Health Care In this study, patient data from hospitals in which anesthesia was provided by anesthesiologists or nurse anesthetists. The data were over a period from surgical patient was a to the severity of or disease and the of postoperative morbidity or patient outcome was with the outcome from the health status and operative Although than were enrolled in this study, the found that outcomes were than for who their care in a nurse than for who their care in a and than for who their care in an anesthesia care Table The there was no between the groups to the small number of patients, the mortality and the hospitals with physician anesthesia providers with hospitals with nurse providers. of this study is that the data were based on clinical care provided more than years by Anesthesia would an anesthesia care offer the Although training, medical and health care and health status of have been as the for outcomes in anesthesia, these hold for all anesthesia delivery models. between the anesthesia delivery models must be to for outcomes of who receive their care from an anesthesia care These may be to of the anesthesia care In many anesthesia care environments, physicians are two or more physician with a provider in an operating room. Whether the provider is a resident anesthesiologists' or nurse the and of this may them to and to patient care The of is in the delivery of anesthesia care This model is to models used to care for in intensive care a with an individual patient in of these more than one physician and more than one nurse or other provider are rapidly to with the care of that These the rapid that an anesthesia care model can to a and it may be the to patient patient outcomes with care provided by anesthesia care and practices have been by a study of hospital and mortality elective The a and an the medical of for and for from They patient of as with the severity and of and and hospital number of number of physicians, and certification and This information was for with and to and postoperative mortality They found that were with patient to an with the of board-certified anesthesiologists on staff in each the the of board-certified anesthesiologists to other anesthesia the of from patient outcomes, as by a in perioperative mortality were with an increased number of board-certified anesthesiologists Since and of perioperative mortality the number of anesthesiologists has grown and at the same and at the same patient outcomes have This is shown in Figure to the the of anesthesiologists to anesthetists has increased from to and over the same period, outcomes have While these have costs have In the of the United States, costs have from more than year in the to the current cost of year 1995). these are based on the experience of with and patient outcomes, the in costs to anesthesiologists during this period a in anesthesia care provided by This is by a of anesthesia services and provider by In that it was of the risks with anesthesia that it would not be to anesthesia by a under the supervision of an or an operative These associations not a between the changing of anesthesia providers and outcomes, but they are with the that the of physicians in anesthesia care has to of the number of physicians in the practice of anesthesiology to the mortality rate related to anesthesia. ASA American Society of and regulations. Federal Register. July 31, 1992;57:33879-96. of Anesthesia Care have various of anesthesia including who the the practice in which the care is and the and of with all medical it has been that with outcomes there are increased Anesthesia care is no and over the years there has been a steady in the cost of care. with anesthesia services represent of the health care costs in the United States. Health evaluation for acute Minnesota Department of The cost of anesthesia care are Not are there costs with the delivery of anesthesia care (e.g., cost of and provider but there can be additional costs with the care (e.g., perioperative with other and The anesthesia care can be for This practice model the patient outcomes and outcomes are with cost and Health and for to the of the anesthesia care for patient care and The health organization in the United States, delivers anesthesia services the anesthesia care model of its and quality of patient care. anesthesia care are found throughout the in model health a be it the patient, or third-party costs related to the delivery of anesthesia care are are in the for an of independent of the costs to health care providers. They have of that were in one may be and each may have its For example, and been intensive care and operating room but they are commonly This has it for to for an of care. in for one of the of care has been This for professional as as hospital and outpatient facility In to the cost to the patient and the for the entire of care must be least one has to anesthesia services at approximately the same rate for any given of patient and surgical of the services are or who A relative has been used for anesthesia since the has been a For example, an has a three in to a that has a These are to four hour of with an for and by a factor. In Minnesota, Medicare anesthesia services in at is throughout the United In similar that similar of have similar anesthesia of provider this there is a four-year period in which the anesthesia care is an with a the of the fourth year of the Medicare reimbursement for an care will be equivalent to The range of services provided in a nurse practice model is This in to each of the practice may additional provider services. who provide care or in a care are to provide comprehensive perioperative medical and postoperative pain services. Table and Table of in under Medicare for professional anesthesia services. These are not and are modified from a 1994 of the Society of Anesthesiologists They the in to between the comprehensive services provided by practice models anesthesia care and with the nurse The of anesthesiologists to diagnose and treat not to a quality of patient as by patient outcomes, but may be less to and their This cost-effectiveness is in patients, who more perioperative care than patients. are very that have the of provider type on the costs of anesthesia services. studies of this should receive from and Medicare for in a Medicare for in a Patient with and/or This report has presented a of anesthesia services and the patient care and cost of these services. The of anesthesia care the of the patient to Anesthesiology is a medical that the of and providers. from anesthesia have over the For many patients, it is as to be as to be a in an on 1993 Minnesota Department of 1994). have to in outcomes, but the of board-certified anesthesiologists has been with the in and commonly to perioperative The anesthesia care and practices to be the of anesthesia care. This may be in to the rapid of physicians, during medical the data are the is very that the anesthesia care is the and most of anesthesia care. this policy decisions should the of anesthesia care in the rural and the of this patient care the Minnesota Commissioner of Health presented a report to the Minnesota Committee on Health The report a result of the reimbursement to anesthesia providers and the increased on cost Minnesota hospitals have to their to to to for new service delivery models that would the of providers in their delivery of and be cost hospitals the to their CRNAs from their hospital staff and to contract for services. The providers are responsible for the and not the and for quality service to the This based on and the changing cost to these The of health care market will as the market shift and and In anesthesia services to be provided in a anesthesiologists and with current very The market and for CRNAs and anesthesiologists is changing and can in this market for