Practice Advisory for Preanesthesia Evaluation

Abstract

PRACTICE Advisories are systematically developed reports that are intended to assist decision-making in areas of patient care. Advisories provide a synthesis and analysis of expert opinion, clinical feasibility data, open forum commentary, and consensus surveys. Practice Advisories developed by the American Society of Anesthesiologists (ASA) are not intended as standards, guidelines, or absolute requirements, and their use cannot guarantee any specific outcome. They may be adopted, modified, or rejected according to clinical needs and constraints and are not intended to replace local institutional policies.Practice Advisories are not supported by scientific literature to the same degree as standards or guidelines because of the lack of sufficient numbers of adequately controlled studies. Practice Advisories are subject to periodic update or revision as warranted by the evolution of medical knowledge, technology, and practice.This document updates the “Practice Advisory for Preanesthesia Evaluation: A Report by the American Society of Anesthesiologists Task Force on Preanesthesia Evaluation,” adopted by the ASA in 2001 and published in 2002.*The literature does not provide a standard definition for preanesthesia evaluation. For this Practice Advisory, preanesthesia evaluation is defined as the process of clinical assessment that precedes the delivery of anesthesia care for surgery and for nonsurgical procedures. For this Advisory, “perioperative” refers to the care surrounding operations and procedures. The preanesthetic evaluation is the responsibility of the anesthesiologist.Preanesthesia evaluation consists of the consideration of information from multiple sources that may include the patient's medical records, interview, physical examination, and findings from medical tests and evaluations. As part of the preanesthesia evaluation process, the anesthesiologist may choose to consult with other healthcare professionals to obtain information or services that are relevant to perioperative anesthetic care. Preoperative tests, as a component of the preanesthesia evaluation, may be indicated for various purposes, including but not limited to (1) discovery or identification of a disease or disorder that may affect perioperative anesthetic care; (2) verification or assessment of an already known disease, disorder, medical or alternative therapy that may affect perioperative anesthetic care; and (3) formulation of specific plans and alternatives for perioperative anesthetic care.The assessments made in the process of preanesthetic evaluation may be used to educate the patient, organize resources for perioperative care, and formulate plans for intraoperative care, postoperative recovery, and perioperative pain management.The purposes of this Advisory are to (1) assess the currently available evidence pertaining to the healthcare benefits of preanesthesia evaluation, (2) offer a reference framework for the conduct of preanesthesia evaluation by anesthesiologists, and (3) stimulate research strategies that can assess the healthcare benefits of a preanesthesia evaluation.A preanesthesia evaluation is considered a basic element of anesthesia care. Therefore the focus of this Advisory is the assessment of evidence pertaining to the content and timing of a preanesthesia evaluation. The interactions between the preanesthesia evaluation, preoperative testing, and perioperative care are beyond the scope and mandate of the Advisory. Informed consent, often undertaken at the same time as the preanesthesia evaluation, is also beyond the scope of this Advisory.This Advisory is intended for use by anesthesiologists and those who provide care under the direction of an anesthesiologist. The Advisory applies to patients of all ages who are scheduled to receive general anesthesia, regional anesthesia, and moderate or deep sedation for elective surgical and nonsurgical procedures. The Advisory does not address the selection of anesthetic technique; nor does it address the preanesthetic evaluation of patients requiring urgent or emergency surgery or anesthetic management provided on an urgent basis in other locations, (e.g. , emergency rooms).Any evaluations, tests, and consultations required for a patient are done with the reasonable expectation that such activities will result in benefits that exceed the potential adverse effects. Potential benefits may include a change in the content or timing of anesthetic management or perioperative resource use that may improve the safety and effectiveness of anesthetic processes involved with perioperative care. Potential adverse effects may include interventions that result in injury, discomfort, inconvenience, delays, or costs that are not commensurate with the anticipated benefits.The original Advisory was developed by an ASA-appointed task force of 12 members, consisting of anesthesiologists from various geographic areas of the United States and two methodologists from the ASA Committee on Standards and Practice Parameters.The Task Force developed the original Advisory by means of a six-step process. First, they reached consensus on the criteria for evidence of effectiveness of preanesthesia evaluation. Second, original published articles from peer-reviewed journals relevant to preanesthesia evaluation were evaluated. Third, consultants who had expertise or interest in preanesthesia evaluation and who practiced or worked in various settings (e.g. , academic and private practice) were asked to (1) participate in opinion surveys on the effectiveness of various preanesthesia evaluation strategies, and (2) review and comment on a draft of the Advisory developed by the Task Force. Fourth, additional opinions were solicited from active members of the ASA. Fifth, the Task Force held several open forums at three major national anesthesia meetings†to solicit input on the draft Advisory. Sixth, all available information was used to build consensus within the Task Force to finalize the Advisory. A summary of recommendations may be found in appendix 1.In 2009, the ASA Committee on Standards and Practice Parameters requested that scientific evidence for this Advisory be updated. The update consists of an evaluation of literature published after completion of the original Advisory. The draft of this updated document was made available for review on the ASA Web site.Preparation of this update used the same methodological process as was used in the original Advisory to obtain new scientific evidence. Opinion-based evidence obtained from the original Advisory is reported in this update. The protocol for reporting each source of evidence is described.Study findings from published scientific literature were aggregated and are reported in summary form by evidence category, as described below. All literature (e.g. , randomized controlled trials, observational studies, case reports) relevant to each topic was considered when evaluating the findings. However, for reporting purposes in this document, only the highest level of evidence (i.e. , level 1, 2, or 3 identified below) within each category (i.e. , A, B, or C) is included in the summary.Randomized controlled trials report statistically significant (P < 0.01) differences between clinical interventions for a specified clinical outcome.Information from observational studies permits inference of beneficial or harmful relationships among clinical interventions and clinical outcomes.The literature cannot determine whether there are beneficial or harmful relationships among clinical interventions and clinical outcomes.The lack of scientific evidence in the literature is described by the following terms.The available literature cannot be used to assess relationships among clinical interventions and clinical outcomes. The literature either does not meet the criteria for content as defined in the “Focus” of the Advisory or does not permit a clear interpretation of findings due to methodological concerns (e.g. , confounding in study design or implementation).No identified studies address the specified relationships among interventions and outcomes.Numerous methodological concerns were encountered in the preanesthesia evaluation literature, including (1) lack of “no-test” controls, (2) failure to blind the practitioner to test results before and during the procedure, and (3) confounding of outcomes. These concerns limit the interpretability of published findings and are discussed in more detail in appendix 2.The original Advisory contained formal survey information collected from expert consultants and random samples of active members of the ASA. Additional information was obtained from open forum presentations and other invited and public sources. All opinion-based evidence relevant to each topic (e.g. , survey data, open-forum testimony, Internet-based comments, letters, and editorials) was considered in the development of the original Advisory. However, only the findings obtained from formal surveys are reported.Survey responses from Task Force-appointed expert consultants and specialty society members obtained during development of the original Advisory are summarized in the text and reported in appendix 2, tables 1–5.A preanesthesia history and physical examination precedes the ordering, requiring, or performance of specific preanesthesia tests and consists of (1) evaluation of pertinent medical records, (2) patient interview(s), and (3) physical examination. No controlled trials of the clinical impact of performing a preanesthesia medical records review or physical examination were found (Category D evidence ). Observational studies of asymptomatic or nonselected surgical patients reported associations between several preoperative patient characteristics (e.g. , age, health status) and postoperative morbidity and mortality (Category B2 evidence ).1–14Several observational studies reported perioperative complications (e.g. , cardiac, respiratory, renal, hemorrhagic) associated with specific preexisting conditions (e.g. , diabetes, pulmonary disease, chronic hypertension, previous myocardial infarction, history of smoking, high body mass index, extremes of age) (Category B2 evidence ).15–55These associations do not provide evidence regarding the clinical impact of perioperative interventions that may be derived from preoperative knowledge of a patient's condition. Additional studies were examined that reported changes in resource management based on preexisting conditions (e.g. , airway abnormalities, cardiopulmonary disorders) detected during a preanesthetic examination, interview, or questionnaire administration (Category B2 evidence ).56–61The activities encompassed by a preanesthetic history and physical examination occur over a variable period of time. The timing of an initial preanesthetic evaluation is guided by such factors as patient demographics, clinical conditions, type and invasiveness of procedure, and the nature of the healthcare system. Three options that practices use for the timing of an initial preanesthetic evaluation are: (1) always before the day of surgery, (2) either on or before the day of surgery, and (3) only on the day of surgery.Consultant and ASA member opinions regarding the timing of an initial assessment of pertinent medical records for high, medium, and low levels of surgical invasiveness, independent of medical condition, were obtained during development of the original Advisory and are reported in table 1(appendix 2). The majority of consultants and ASA members agree that for high surgical invasiveness, the initial assessment of pertinent medical records should be done before the day of surgery by anesthesia staff. For medium surgical invasiveness, the majority of consultants indicate that the initial assessment of pertinent medical records should be done before the day of surgery by anesthesia staff, although the majority of ASA members indicate that the initial assessment may be done on or before the day of surgery. For low surgical invasiveness, the majority of consultants and ASA members agree that the initial assessment may be done on or before the day of surgery.Consultant and ASA membership opinions regarding the timing of an initial preanesthetic interview and physical examination for high and low severities of disease are reported in table 2(appendix 2). The majority of consultants and ASA members agree that, for patients with high severity of disease, it is preferable that the interview and physical examination be done before the day of surgery by anesthesia staff. For low severity of disease and high surgical invasiveness, consultants and ASA members agree that it is preferable that the interview and physical examination should be done before the day of surgery. For patients with low severity of disease and medium or low surgical invasiveness, consultants and ASA members agree that the interview and physical examination may be done on or before the day of surgery.A majority of consultants and the ASA membership, respectively, agree that, at a minimum , a preanesthetic physical examination should include (1) an airway examination (100%, 100%), (2) a pulmonary examination to include auscultation of the lungs (88%, 85%), and (3) a cardiovascular examination (81%, 82%).The assessment of anesthetic risks associated with the patient's medical conditions, therapies, alternative treatments, surgical and other procedures, and of options for anesthetic techniques is an essential component of basic anesthetic practice. Benefits may include, but are not limited the safety of perioperative care, resource and patient assessment of pertinent medical records with when should be as part of the preanesthetic evaluation before the day of surgery for with high surgical For with low surgical invasiveness, the review and assessment of medical records may be done on or before the day of surgery by anesthesia staff. The information obtained may include, but should not be limited (1) a of (2) treatments, including and alternative and (3) of the patient's medical The Task Force that the timing of such assessments may not be with the of resources provided in specific healthcare or initial patient interview, and physical examination should be before the day of surgery for patients with high severity of For patients with low severity of disease and those with high surgical invasiveness, the interview and physical should also be before the day of surgery. For patients with low severity of disease with medium or low surgical invasiveness, the initial interview and physical may be on or before the day of surgery. a minimum , a preanesthetic physical examination should include an assessment of the and with of Task Force it is the of the healthcare at a provide pertinent information to the anesthesiologist for the assessment of the severity of medical of the patient and invasiveness of the surgical in of the anticipated day of for all elective regarding controlled trials and test findings regarding the or of used preoperative tests are described below. For purposes of this Advisory, a test is defined as a test in the of a specific clinical or such as or are not considered as specific clinical or indicated test is defined as a test that is for a specific clinical or For assessment of therapy effects be considered an for specific studies report findings for asymptomatic or nonselected patients from to of patients (Category B2 evidence findings to of surgery or changes in management in of (Category B2 evidence studies report findings for that were as indicated tests in of to or changes in management in of (Category B2 evidence observational study with and practitioner found that preoperative were associated with intraoperative and postoperative myocardial for patients with disease scheduled for elective surgery (Category B2 evidence observational study reports findings in of asymptomatic or nonselected patients (Category B2 evidence observational study reports test in of asymptomatic or nonselected to a management change in of the (Category B2 evidence patients with observational studies report findings in of to of surgery in of (Category B2 evidence or indicated or test findings were reported for of to additional in of patients with findings (Category B2 evidence study of surgery patients a preoperative test reports a mortality with patients not a preoperative test (Category B2 evidence findings indicated low (e.g. , in of patients (Category B2 evidence findings were reported as in of asymptomatic or nonselected to or changes in management in of found to be (Category B2 evidence or indicated findings were reported in of to or changes in management in of the with findings (Category B2 evidence studies reported findings in of asymptomatic or nonselected patients (Category B2 evidence in clinical management were not or indicated pulmonary test findings were reported in of findings were reported in of patients (Category B2 evidence in clinical management were not asymptomatic or nonselected findings were reported in to of to or changes in management in of with findings (Category B2 evidence or indicated findings were reported in of patients (Category B2 evidence in clinical management were not asymptomatic or nonselected findings were reported in of to of surgery in of the with findings (Category B2 evidence asymptomatic or nonselected (i.e. , test results not were reported in of to changes in clinical management in of with findings (Category B2 evidence or indicated were reported in of to changes in clinical management in of the with findings (Category B2 evidence asymptomatic or nonselected (i.e. , or were reported in of to or changes in management in of with findings (Category B2 evidence or indicated findings were reported in of patients (Category B2 evidence in clinical management were not asymptomatic or nonselected were reported in of were reported in of were reported in of patients (Category B2 evidence in clinical management were not or indicated were reported in of patients (Category B2 evidence study preoperative 3 before surgery with at and found at (Category B2 evidence in clinical management were not asymptomatic or nonselected findings for not including testing, were reported in of to or changes in management in of the with findings (Category B2 evidence or indicated not including testing, were reported in of to changes in clinical management in of with findings (Category B2 evidence asymptomatic or nonselected patients (i.e. , not on the basis of test findings were reported in of to or changes in management in of the of (Category B2 evidence the original Advisory, consultants and ASA members were asked to whether specific preoperative tests (1) should be on a basis (i.e. , to patients of known or or (2) should be for patients or for of surgery, or (3) are not For the tests and ASA membership responses are reported in table 2). and ASA members were also asked to specific patient characteristics that a to or a preoperative For specific patient and ASA membership responses are reported in table and ASA members were asked whether or not they agree that preoperative test results are obtained from the patient's medical the patient's medical history not the test result was The of of consultants and ASA members are respectively, as other evaluation or studies and who that test findings be obtained from a patient's medical were asked the findings should be to be on test findings should be are reported in table tests should not be Preoperative tests may be or on a basis for purposes of or perioperative The for such should be and based on information obtained from medical records, patient interview, physical examination, and type and invasiveness of the Task Force that there is evidence to or for preoperative tests on the basis of specific clinical However, consideration of clinical characteristics may assist the anesthesiologist when to or preoperative The following clinical characteristics may be of although the anesthesiologist should not limit consideration to the characteristics clinical characteristics may include disease, disease, and type or invasiveness of surgery. The Task Force that may be more in patients and in patients with multiple The Task Force not consensus on a specific minimum in those patients specific The Task Force that may not be an for may be indicated for patients with known cardiovascular factors or for patients with factors identified in the of a preanesthesia evaluation may include with and ordering, requiring, or performing tests that from or tests (e.g. , to and assessment of and (e.g. , Anesthesiologists should the risks and costs of their characteristics to include cardiovascular factors and type of characteristics to include smoking, chronic pulmonary disease and The Task Force that may be in such patients but does not that extremes of age, smoking, disease, or should be considered for pulmonary evaluation other may include with and tests that from or tests (e.g. , pulmonary tests, to assessment of pulmonary (e.g. , Anesthesiologists should the risks and costs of their characteristics to include type and invasiveness of the surgical procedure, from previous evaluation, or and with or is not characteristics to as for such tests include type and invasiveness of procedure, patients with disease, extremes of age, and history of and other characteristics to for studies include and type and invasiveness of The Task Force that and alternative may an additional perioperative The Task Force that there were not to comment on the of tests before regional characteristics to before such tests include perioperative therapies, of and and use of or alternative The Task Force that may from at extremes of is not indicated for specific (e.g. , or when are may for anesthesia with The Task Force that the literature is to patients or on whether anesthesia harmful effects on may be to patients of and for the result the patient's management.The literature is not to permit an assessment of the clinical benefits or of the timing for preoperative The Task Force that there is evidence to or for preoperative tests on the basis of specific patient results obtained from the medical within of surgery are the patient's medical history not test results may be when the medical history or when a test results may a in the selection of a specific anesthetic (e.g. , regional anesthesia in the of preanesthesia evaluation the assessment of information from multiple including medical records, patient physical and findings from preoperative scientific literature does not information the of a preanesthesia evaluation to permit recommendations that are the Task Force observational literature, opinion surveys of and surveys of a random of members of the American Society of The focus of opinion surveys (1) the content of the preanesthesia evaluation, (2) the timing of the preanesthesia evaluation, and (3) the for specific preoperative following a synthesis of the opinion literature, and Task Force Task Force that in resources available to a specific healthcare or may affect the timing of the preanesthetic evaluation. The healthcare is to provide pertinent information to the anesthesiologist for the assessment of the invasiveness of the surgical and the severity of the patient's medical in of the anticipated day of for all elective this updated Advisory, a review of studies used in the development of the original Advisory was with a review of studies published to of the original Advisory. The updated literature review was based on evidence consisting of relationships between specific preanesthesia evaluation activities and clinical outcomes. The evidence interventions are and For purposes of literature relevant clinical studies were identified and of the The updated a period from The a period of time from new that to the evidence were These articles were and studies that not provide evidence were that were as evidence were with articles by the Advisory, in a of evidence contained sufficient literature with and information to conduct an analysis of aggregated studies (i.e. , A used to this updated Advisory, by is available as 2, study or report that in the published literature can be included as evidence in the development of an it essential to meet or more of criteria means that a study had that not it for The essential criteria are as (1) the study be to of the specified (2) the study report a clinical or of findings that can be or reports that only (3) the study report a clinical or of findings that can be identified as the of an original or report the reporting and of the same such as may occur in review articles or studies that previous and the study use research and that provide a clear test or of the between the and of of the studies in this updated Advisory all the published literature not be used as a source of evidence are to assess the studies not provide a clear of However, published studies were that provided the Task Force with evidence. For literature (i.e. , reports of or is often in an of the scope of a and case reports may be in the of preoperative tests for the literature not in the of specific preanesthesia evaluation activities in patient outcome. controlled studies are evidence from sources will to be such as and the opinion of and is that research on preanesthesia evaluation focus on the identification of preoperative tests or other activities in the of research when the original Advisory, consensus was obtained from multiple including (1) survey opinion from consultants who were based on their knowledge or expertise regarding preanesthesia or preoperative evaluation, (2) survey opinions from a of ASA members (3) from of three held open forums at national anesthesia commentary, and Task Force opinion and and ASA members to three surveys the following (1) the and of for evidence (2) the and to include for timing of the preanesthesia evaluation, and (3) surveys regarding the timing and content of the preanesthesia evaluation and for The survey of for consultants was of the ASA members responses for consultants and ASA members are in the text of the Advisory, and of survey responses are reported in tables the original Advisory, consultants were asked to indicate of the evidence change their clinical practices the Advisory was The of was of The of consultants change associated with each were as (1) review of medical records, or other (2) preanesthesia patient examination (3) patient for medical or anesthesia history timing of the preanesthesia evaluation or performing preanesthesia or performing other performing preanesthesia pulmonary tests performing preanesthesia performing preanesthesia tests and performing preanesthesia tests the indicated that the Advisory on the of time on a and indicated that there be a in the of time on a case with the of this Advisory.