Reliability of the Pediatric-Specific American Society of Anesthesiologists Physical Status (ASA-PS) Classification System.

The American Society of Anesthesiologists physical status (ASA-PS) classification system is used worldwide to classify patients based on comorbid conditions before general anesthesia. Despite its popularity, the ASA-PS classification system has been shown to have poor interrater reliability due to its subjective definitions, especially when applied to the pediatric population. We hypothesized that the clarification of ASA-PS definitions to better reflect pediatric conditions would improve the accuracy of ASA-PS applied to this population. A stratified, randomized sample of 120 pediatric surgical cases was collected from a tertiary-care pediatric hospital. A team of senior anesthesiologists reclassified ASA-PS within this patient sample using the suggested pediatric-specific ASA-PS definitions. Interrater reliability was measured using intraclass correlation (ICC) and Fleiss κ statistic. In addition, a qualitative study component using small focus groups of senior anesthesiologists identified areas of ambiguity within the ASA-PS system. Among the 90 reclassifications within each ASA-PS group, 42.2% (n = 38) of ASA-PS I were upgraded to ASA-PS II, and 36.7% (n = 33) of ASA-PS II were upgraded to ASA-PS III. In addition, 28.9% (n = 26) of ASA-PS III were upgraded to ASA-PS IV, and 24.4% (n = 22) of ASA-PS IV were downgraded to III. ICC across the reclassified ASA-PS categories was 0.77 (95% confidence interval [CI], 0.71-0.83; P < .001) demonstrating strong overall agreement. Fleiss κ statistic was lowest in ASA-PS II and III patients (κ = 0.41 and κ = 0.30, respectively) indicating lower agreement beyond chance within these subgroups. Focus groups revealed common themes such as active sequelae of disease, active versus well-controlled presence of comorbidities, and the possible inclusion of functional limitations as important considerations. The ASA-PS classification system has several benefits including ease-of-use, simplicity, and flexibility. However, revising the ASA-PS system to provide better guidance for pediatric patients could be valuable. While this study demonstrates good interrater reliability with the included ASA-PS pediatric definitions, further work is needed to clarify accurate assignment of ASA-PS within the midrange of the scale (ASA-PS II and III) and explore its implementation in other institutions.

BackgroundThe American Society of Anesthesiologists Physical Status (ASA-PS) classification system was developed to categorize the fitness of patients before surgery. Increasingly, the ASA-PS has been applied to other uses including justification of inpatient admission. Our objectives were to develop and cross-validate a statistical model for predicting ASA-PS; and 2) assess the concurrent and predictive validity of the model by assessing associations between model-derived ASA-PS, observed ASA-PS, and a diverse set of 30-day outcomes.MethodsUsing the 2014 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Participant Use Data File, we developed and internally cross-validated multinomial regression models to predict ASA-PS using preoperative NSQIP data. Accuracy was assessed with C-Statistics and calibration plots. We assessed both concurrent and predictive validity of model-derived ASA-PS relative to observed ASA-PS and 30-day outcomes. To aid further research and use of the ASA-PS model, we implemented it into an online calculator.ResultsOf the 566,797 elective procedures in the final analytic dataset, 8.9% were ASA-PS 1, 48.9% were ASA-PS 2, 39.1% were ASA-PS 3, and 3.2% were ASA-PS 4. The accuracy of the 21-variable model to predict ASA-PS was C = 0.77 +/− 0.0025. The model-derived ASA-PS had stronger association with key indicators of preoperative status including comorbidities and higher BMI (concurrent validity) compared to observed ASA-PS, but less strong associations with postoperative complications (predictive validity). The online ASA-PS calculator may be accessed at https://s-spire-clintools.shinyapps.io/ASA_PS_Estimator/ConclusionsModel-derived ASA-PS better tracked key indicators of preoperative status compared to observed ASA-PS. The ability to have an electronically derived measure of ASA-PS can potentially be useful in research, quality measurement, and clinical applications.

The American Society of Anesthesiologists Physical Status (ASA-PS) classification system is ubiquitous in perioperative medicine and research as a tool for preoperative patient risk stratification. Despite widespread clinical adoption as a predictor of perioperative outcomes, the ASA-PS system is inherently subjective, leading to considerable inter-rater variability. A comprehensive mapping of the literature examining the relationship between ASA-PS scores and patient outcomes is lacking. To systematically map the extent, range, and nature of peer-reviewed literature examining the relationship between the ASA-PS classification and patient outcomes, and to identify key characteristics, themes, and knowledge gaps in this evidence base. This scoping review will be conducted according to the Joanna Briggs Institute (JBI) methodological framework and reported using the Preferred Reporting Items for Systematic Review and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR). The Population-Concept-Context (PCC) framework will guide eligibility assessment. A comprehensive search will be conducted across PubMed, EMBASE, Scopus, LILACS, and the Cochrane Central Register of Controlled Trials, with no language or date restrictions. Study selection will be performed independently and in duplicate by two reviewers in two stages (title/abstract screening, full-text review). If any discordance appears, a third reviewer verdict will be requested. Data will be extracted using a structured charting form and synthesized narratively. Any healthcare setting where an ASA-PS score is assigned prior to a procedure (inpatient hospital, ambulatory surgery center, outpatient clinic). Primary research designs, including randomized controlled trials, observational studies (cohort, case-control, cross-sectional, descriptive), and case reports will be eligible; review articles, editorials, letters to the editor, and commentaries will be excluded. The search will employ controlled vocabulary (MeSH terms) and free-text keywords including: "ASA score," "ASA Physical Status Classification System," "American Society of Anesthesiologists," in combination with outcome-related terms. Supplementary hand searching of reference lists and Google Scholar will be performed. Study characteristics (author, year, country, journal, design), population characteristics (sample size, age, comorbidity), context (clinical setting, specialty, procedure type, urgency), ASA score details, and outcome details (including statistical methods used to derive associations) will be extracted. A preliminary data charting form is provided in Appendix B. Narrative synthesis supported by descriptive statistics will map study characteristics, outcome categories, clinical contexts, study designs, and temporal and geographical distribution of research. No formal quality appraisal will be conducted. Ethics committee approval is not required for this protocol-based scoping review.

Endoscopic submucosal dissection (ESD) is becoming widely popular as a less invasive treatment option for superficial esophageal squamous cell carcinoma. However, data on long-term survival after esophageal ESD in patients with severe comorbidities are limited. This study aimed to evaluate long-term survival after ESD in such patients. Altogether, 584 consecutive patients underwent esophageal ESD at our institution from May 2004 to September 2016. Based on the American Society of Anesthesiologists Physical Status (ASA-PS) classification system, patients were grouped according to severe (ASA-PS ≥ 3) or non-severe comorbidities (ASA-PS 1/2). The overall survival (OS), disease-specific survival (DSS), and risk factors for mortality were compared between the groups using a propensity score matching analysis. In a matched cohort of 69 pairs, the 5-year OS rate was poorer in ASA-PS 3 patients than in ASA-PS 1/2 patients (63.9% vs. 92.5%, P < 0.01), while the 5-year DSS rate was similar between the groups (100% vs. 100%). The mortality rate was significantly higher in ASA-PS 3 patients than in ASA-PS 1/2 patients (hazard ratio 3.47; 95% confidence interval 1.79-6.74; P < 0.01). Death due to exacerbation of comorbidities was significantly more frequent in ASA-PS 3 patients than in ASA-PS 1/2 patients (42.4% vs. 8.3%, P < 0.04). Because of the exacerbation of comorbidities, patients with severe comorbidities had poorer long-term outcomes after esophageal ESD than those with non-severe comorbidities. Further studies will be necessary to evaluate esophageal ESD in patients with severe comorbidities.

We thank Drs. Avidan and Weiniger for their comments related to our article, “Adding Examples to the ASA-Physical Status Classification Improves Correct Assignment to Patients.”1 They posit that the addition of objective examples to the previously subjective American Society of Anesthesiologists Physical Status (ASA-PS) Classification System may hinder the universal application of the ASA-PS score by unnecessarily increasing the complexity of the system.As stated in their letter, “the ASA score has penetrated beyond anesthesia.” It is our belief that this is exactly why the examples should be used. With the increasing use of the ASA-PS score by nonanesthesia providers, there are many assigning ASA-PS who do not have the anesthesia-related training to understand the differences between classifications. Although we agree that physician anesthesiologists currently use “common sense” in determining the ASA-PS, the gestalt that many of us have in applying the ASA-PS in practice may not exist for those who do not have experience in anesthesiology. Additionally, poor interrater reliability for the ASA-PS has been shown repeatedly.2–4 For these reasons, the ASA-PS examples may ultimately prove more useful for nonanesthesia providers than anesthesia ones. As we demonstrated, with examples there was improvement in correct assignment for anesthesia and nonanesthesia providers with no significant difference in the rate of correct assignment between anesthesia-trained and nonanesthesia clinicians.1 We reiterate that the examples are guidelines and recognize the list is not comprehensive; the examples should provide a framework indicating the most likely appropriate ASA-PS score for commonly encountered diseases. The final determination of ASA-PS should be made by a physician anesthesiologist. We recognize that until further studies are done, the true effect of these examples in clinical practice is yet to be seen. We agree that uniform application across the board, even with examples, is unlikely, but given the inconsistency that already exists with ASA-PS score assignments, it is hard to argue that an addition with the potential to improve objective scoring should not be used clinically.The author declares no competing interests.

The American Society of Anesthesiologists (ASA) physical status (PS) classification system assesses the preoperative health of patients. Previous studies demonstrated poor interrater reliability and variable ASA PS scores, especially in trauma scenarios. There are few studies that evaluated the assignment of ASA PS scores in trauma patients and no studies that evaluated ASA PS assignment in severely injured adult polytrauma patients. Our objective was to assess interrater reliability and identify sources of discrepancy among anesthesiologists and trauma surgeons in designating ASA PS scores to adult polytrauma patients. A link to an online survey containing questions assessing attitudes regarding ASA PS classification, demographic information, and 8 fictional trauma cases was e-mailed to anesthesiologists and trauma surgeons. The participants were asked to assign an ASA PS score to each scenario and explain their choice. Rater-versus-reference and interrater reliability, beyond that expected by chance, among respondents was analyzed using the Fleiss kappa analysis. A total of 349 participants completed the survey. All 8 cases had inconsistent ASA PS scores; several cases had scores ranging from I to VI and variable emergency (E) designations. Using weighted kappa (Kw) analysis for a subset of 201 respondents (101 trauma surgeons [S] and 100 anesthesiologists [A]), we found moderate (Kw = 0.63; SE = 0.024; 95% confidence interval, 0.594-0.666; P < .001) interrater-versus-reference reliability. The interrater reliability was fair (Kw = 0.43; SE = 0.037; 95% confidence interval, 0.360-0.491; P < .001). This study demonstrates fair interrater reliability beyond that expected by chance of the ASA PS scores among anesthesiologists and trauma surgeons when assessing adult polytrauma patients. Although the ASA PS is used in some trauma risk stratification models, discrepancies of ASA PS scores assigned to trauma cases exist. Future modifications of the ASA PS guidelines should aim to improve the interrater reliability of ASA PS scores in trauma patients. Further studies are warranted to determine the value of the ASA PS score as a trauma prognostic metric.

The ability of an organism to withstand trauma is determined by the injury per se and inherent properties of the organism at the time of injury. We analyzed whether pre-injury morbidity scored on a four-level ordinal scale according to the American Society of Anesthesiologists Physical Status (ASA-PS) classification system predicts mortality after trauma. From a total of 3,773 prospectively collected patients (years 2000-2004), 3,728 patients were included. Main outcome measure was mortality 30 days after injury. The effect of pre-injury ASA-PS on mortality was assessed using linear logistic regression analysis, controlling for Revised Trauma Score (RTS), Injury Severity Score (ISS), and age. Mortality increased with increasing pre-injury ASA-PS, age, and ISS, and with decreasing RTS. Unadjusted mortality rates were 5.7% in ASA-PS 1, 12.3% in ASA-PS 2, and 26.4% in ASA-PS 3-4. This increasing mortality trend across pre-injury ASA-PS group was evident in nearly all categories of ISS, RTS, and age. Odds ratio for death was 1.76 (95% CI, 1.14-2.72) for pre-injury ASA-PS 2, and 2.25 (95% CI, 1.36-3.71) for ASA-PS 3-4 compared with for ASA-PS 1 and adjusted for ISS, RTS, and age. There were no interaction effects between pre-injury ASA-PS and the other variables. Pre-injury ASA-PS score was an independent predictor of mortality after trauma, also after adjusting for the major variables in the traditional TRISS (Trauma and Injury Severity Score) formula. Including pre-injury ASA-PS score might improve the predictive power of a survival prediction model without complicating it.

Examples of comorbidities for the widely used American Society of Anesthesiologists physical status (ASA-PS) classification system were developed and approved in 2014. We conducted a retrospective cohort study of patients with 4 comorbidities included in the examples as warranting a specific minimum ASA-PS class. For each comorbidity subgroup, we used interrupted time-series models to compare ASA-PS underclassification for the periods before (2011-2014) and after (2015-2017) the introduction of examples. Rates of underclassification ranged from 4.8% to 38.7%. We observed no evidence of a significant impact on ASA-PS classification with the introduction of examples in 2014.

When applied to the pediatric population, the American Society of Anesthesiologists physical status (ASA-PS) classification has exhibited poor reliability due to its subjective and adult-focused definitions. This study was done to measure interrater agreement of a pediatric-adapted ASA-PS classification and to solicit multicenter perspectives to optimize the pediatric ASA-PS classification. A prospective, mixed-methods study of 197 pediatric anesthesiologists from 13 academic pediatric hospitals in the United States, Europe, and Australia surveyed in May and July 2019. Participants assigned ASA-PS scores (I to V) for 15 pediatric cases with a heterogeneous mix of acute and chronic health conditions undergoing a variety of surgical and related procedures. Pediatric-adapted definitions of ASA-PS were provided. The intraclass correlation coefficient (ICC) was used to assess interrater reliability of ASA-PS scores. The ICC was estimated using 2-way mixed-effects modeling, accounting for multiple raters assigning scores for the same set of cases. Qualitative feedback on the pediatric-adapted ASA-PS classification was analyzed with line-by-line coding. The survey response rate was 83.8% (165 of 197). The ICC agreement among participants on ASA-PS scoring across all 15 clinical cases was 0.58 (95% confidence interval [CI], 0.42-0.77). ICC did not vary significantly by years of anesthesiology practice. ICC varied across hospitals (range: 0.34; 95% CI, 0.12-0.63 to 0.79; 95% CI, 0.66-0.91). The highest level of agreement occurred with cases most often scored as ASA-PS I, IV, and V; the lowest agreement occurred with cases most often scored ASA-PS II and III. Clarification of how well a chronic condition was controlled and presence of an acute illness were 2 common themes suggested to optimize the validity of the pediatric-adapted ASA-PS definitions. The pediatric-adapted ASA-PS classification had moderate interrater reliability among pediatric anesthesiologists. The lower reliability of scoring for ASA-PS II and III cases, in particular, supports the need for further ASA-PS definition refinement for pediatric populations.

The American Society of Anesthesiologists (ASA) Physical Status Classification System has been used to assess pre-anesthesia comorbid conditions for over 60 years. However, the ASA Physical Status Classification System has been criticized for its subjective nature. In this study, we aimed to assess the correlation between the ASA physical status assignment and more objective measures of overall illness.This is a single medical center, retrospective cohort study of adult patients who underwent surgery between November 2, 2017 and April 22, 2020. A multivariable ordinal logistic regression model was developed to examine the relationship between the ASA physical status and Elixhauser comorbidity groups. A secondary analysis was then conducted to evaluate the capability of the model to predict 30-day postoperative mortality.A total of 56,820 cases meeting inclusion criteria were analyzed. Twenty-seven Elixhauser comorbidities were independently associated with ASA physical status. Older patient (adjusted odds ratio, 1.39 [per 10 years of age]; 95% CI 1.37 to 1.41), male patient (adjusted odds ratio, 1.24; 95% CI 1.20 to 1.29), higher body weight (adjusted odds ratio, 1.08 [per 10 kg]; 95% CI 1.07 to 1.09), and ASA emergency status (adjusted odds ratio, 2.11; 95% CI 2.00 to 2.23) were also independently associated with higher ASA physical status assignments. Furthermore, the model derived from the primary analysis was a better predictor of 30-day mortality than the models including either single ASA physical status or comorbidity indices in isolation (p < 0.001).We found significant correlation between ASA physical status and 27 of the 31 Elixhauser comorbidities, as well other demographic characteristics. This demonstrates the reliability of ASA scoring and its potential ability to predict postoperative outcomes. Additionally, compared to ASA physical status and individual comorbidity indices, the derived model offered better predictive power in terms of short-term postoperative mortality.

BackgroundThe American Society of Anesthesiologists physical status (ASA-PS) classification is not intended to predict risk, but increasing ASA-PS class has been associated with increased perioperative mortality. The ASA-PS class is being used by many institutions to identify patients that may require further workup or exams preoperatively. Studies regarding the ASA-PS classification system show significant variability in class assignment by anesthesiologists as well as providers of different specialties when provided with short clinical scenarios. Discrepancies in the ASA-PS accuracy have the potential to lead to unnecessary testing and cancelation of surgical procedures. Our study aimed to determine whether these differences in ASA-PS classification were present when actual patients were evaluated rather than previously published scenario-based studies.MethodsA retrospective chart review was completed for patients >/= 65 years of age undergoing elective total hip or total knee replacements. One hundred seventy-seven records were reviewed of which 101 records had the necessary data. The outcome measures noted were the ASA-PS classification assigned by the internal medicine clinic provider, the ASA-PS classification assigned by the Pre-Anesthesia Unit (PAU) clinic provider, and the ASA-PS classification assigned on the day of surgery (DOS) by the anesthesia provider conducting the anesthetic care.ResultsA statistically significant difference was shown between the internal medicine and the PAU preoperative ASA-PS designation as well as between the internal medicine and DOS designation (McNemar p = 0.034 and p = 0.025). Low kappa values were obtained confirming the inter-observer variation in the application of the ASA-PS classification of patients by providers of different specialties [Kappa of 0.170 (− 0.001, 0.340) and 0.156 (− 0.015, 0.327)].ConclusionsThere was disagreement in the ASA-PS class designation between two providers of different specialties when evaluating the same patients with access to full medical records. When the anesthesia-run PAU and the anesthesia assigned DOS ASA-PS class designations were evaluated, there was agreement. This agreement was seen between anesthesia providers regardless of education or training level. The difference in the application of the ASA-PS classification in our study appeared to be reflective of department membership and not reflective of the individual provider’s level of training.

We read with great interest the review article on the American Society of Anesthesiologists (ASA; Schaumburg, Illinois) Physical Status Classification System by Horvath et al.1 The review presents in excellent detail the origin, evolution, and current state of the ASA Physical Status system. Further, the authors describe the recent addition of clinical examples to help clarify the classifications. These examples have been useful to provide some consistency in the assignment of ASA Physical Status classifications by anesthesia-trained and non–anesthesia-trained clinicians2 and have been demonstrated to improve communication about patient status to anesthesia providers when assessments are performed by anesthesiologists in preanesthesia clinic settings and before the day of surgery.3As an extension of the historical perspective they have given, the authors also consider whether further refinements or more granular categories might be of value. In proposing that the ASA and anesthesia community revise the ASA Physical Status system, we want to provide some additional background information about the current status of the system and its implications. Although the ASA Physical Status system is used by many anesthesia and nonanesthesia clinicians in the United States and around the world for purposes unrelated to the initial purpose for which it was created, in the United States, physical status modifiers based on (and identical to) the ASA classification system are part of the Current Procedural Terminology, which is a product of the American Medical Association (Chicago, Illinois).4 These billing modifiers are used to justify additional payment by some payers based on the physical status of patients receiving anesthesia care. If the ASA determined that modifications to the current system were warranted, the society would have the ability to make changes to it. However, any changes proposed by the ASA will not impact payment unless the ASA requested revisions to the Current Procedural Terminology–defined physical status modifiers. To do so, the ASA would have to submit an application for a code change at the Current Procedural Terminology level and then a valuation through the American Medical Association Relative Value System Update Committee.5 Although ASA can give input, the Current Procedural Terminology Editorial Board and the American Medical Association Relative Value System Update Committee would make final decisions on the physical status billing modifiers (the definitions, categories, and valuation). This request and approval process takes at least 3 yr to be implemented.Based on this historical background, the ASA, through the House of Delegates and with support and recommendations provided by the ASA Committee on Economics, chose to provide additional examples to better illustrate the application of the definitions and the determination of appropriate ASA Physical Status assignment rather than propose revisions to the categories and definitions. As noted in the review, the initial examples were adopted in 2014 specifically for adult patients. In 2020, examples for pediatric patients and obstetric patients were added with input from the ASA Committees on Pediatric Anesthesia and on Obstetric Anesthesia.The authors are all members of the American Society of Anesthesiologists (ASA) Committee on Economics (Schaumburg, Illinois). S. Merrick is the ASA staff member on the committee.

Anesthesia providers categorize patients utilizing the American Society of Anesthesiologists Physical Status (ASA-PS) classification originally created by the ASA in 1941. There is published variability and discordance among providers when assigning patient ASA scores in part due to the subjectivity of scoring utilizing patient medical conditions, but variability is also found using objective findings like BMI. To date, there are few studies evaluating the accuracy of anesthesia providers' ASA assignment based on objective body mass index (BMI) alone. The aim of this retrospective chart review is to determine improvement in accuracy of anesthesia providers to correctly assign patient ASA scores, based on BMI criteria added to the ASA-PS in October of 2014, utilizing a multifaceted strategy including creation of an active finance committee in the fall of 2015, multiple e-mail communications about the updated definitions and recommendations for ASA-PS scoring in the fall of 2015 and spring of 2016, a department grand rounds presentation in February 2016, placement of laminated copies of the ASA definitions and recommendations in the anesthesia chartrooms, and the development of a tool embedded into our EMR providing a recommendation of ASA-PS based on patient comorbidity findings. After attaining IRB approval, all eligible patients over the age of 18 who had surgical procedures under general anesthesia at Mayo Clinic in Rochester, MN, between January 1, 2010, and December 31, 2020, were retrospectively analyzed. A segmented logistic regression model was used to estimate the trends (per-year change in odds) of ASA under classification according to severity of obesity during 3 epochs: preimplementation (2010-2014), implementation (2015), and postimplementation (2016-2020). A total of 16,467 patients of the 200,423 (8.2%) patients with obesity (class 1, 2, and 3) were underscored based on BMI alone. Accuracy of ASA-PS classification, as it pertains to BMI alone, was found to show meaningful improvement year-to-year following the updated ASA-PS guidelines with examples released in October of 2014 (P < 0.001). Most of the improvement occurred in 2015-2017 with relatively little between-year variability in the rate of underscoring from 2017-2020. Despite updated ASA-PS published guidelines, providers may still be unaware of the updated guidelines and inclusion of examples used within the ASA-PS classification system. Accuracy of scoring did improve annually following the release of the updated guidelines with examples as well as department-wide educational activities on the topic. Additional education and awareness should be offered to those responsible for preanesthesia evaluation and assignment of ASA-PS in patients to improve accuracy as it pertains to BMI.

BackgroundIndividualized treatment is a common principle in hospitals. Treatment decisions are made based on the patient’s condition, including comorbidities. This principle is equally relevant out-of-hospital. Furthermore, comorbidity is an important risk-adjustment factor when evaluating pre-hospital interventions and may aid therapeutic decisions and triage. The American Society of Anesthesiologists Physical Status (ASA-PS) classification system is included in templates for reporting data in physician-staffed pre-hospital emergency medical services (p-EMS) but whether an adequate full pre-event ASA-PS can be assessed by pre-hospital physicians remains unknown. We aimed to explore whether pre-hospital physicians can score an adequate pre-event ASA-PS with the information available on-scene.MethodsThe study was an inter-rater reliability study consisting of two steps. Pre-event ASA-PS scores made by pre- and in-hospital physicians were compared. Pre-hospital physicians did not have access to patient records and scores were based on information obtainable on-scene. In-hospital physicians used the complete patient record (Step 1). To assess inter-rater reliability between pre- and in-hospital physicians when given equal amounts of information, pre-hospital physicians also assigned pre-event ASA-PS for 20 of the included patients by using the complete patient records (Step 2). Inter-rater reliability was analyzed using quadratic weighted Cohen’s kappa (κw).ResultsFor most scores (82%) inter-rater reliability between pre-and in-hospital physicians were moderate to substantial (κw 0,47-0,89). Inter-rater reliability was higher among the in-hospital physicians (κw 0,77 to 0.85). When all physicians had access to the same information, κw increased (κw 0,65 to 0,93).ConclusionsPre-hospital physicians can score an adequate pre-event ASA-PS on-scene for most patients. To further increase inter-rater reliability, we recommend access to the full patient journal on-scene. We recommend application of the full ASA-PS classification system for reporting of comorbidity in p-EMS.

Normative ranges for vital signs under general anesthesia are well established for healthy pediatric patients, but the influence of The American Society of Anesthesiologists Physical Status (ASA-PS) classification on these normative ranges remains unexplored.The purpose of this study is to develop age-based normative ranges for heart rate (HR) and blood pressure (BP) in patients undergoing general anesthesia for noncardiac surgery in our institution and assess differences by ASA-PS classification.This is a retrospective observational single-center study. We reviewed all anesthetic records from the Hospital for Sick Children, Canada between March 1st and December 31st, 2023. We extracted physiological data from our in-house high-resolution physiological data repository (AtriumDB) to develop normative ranges for physiological parameters and compared them according to ASA-PS classification.We developed age-based normative ranges for BP and HR. We found significant differences between ASA-PS groups, most notably between ASA-PS 1 and 5. We found a statistically significant difference between ASA-PS 1-2 and 3-5 across all physiological parameters.This study validates existing pediatric anesthesia reference ranges while demonstrating the feasibility of incorporating patients across the spectrum of ASA-PS. Further multicenter studies are needed to generalize these findings.