Posted by J. Lance Lichtor, M.D.
Though not originally designed for that purpose, the American Society of Anesthesiologists Physical Status Classification System is used to predict risk. The Surgical Apgar score, originally based on based on blood loss, heart rate, and blood pressure, was designed to predict the risk of major complications or death within 30 days of surgery. A group of authors from Vanderbilt University used their perioperative electronic information system to validate the Surgical Apgar score. They analyzed general and vascular surgical patients and found that it can predict outcome after surgery.
Both this study
and it's accompanying editorial
are published ahead of print and will appear in the June issue of Anesthesiology
. The study abstract is below.
: Articles appearing in this Published Ahead-of-Print section have been peer-reviewed and accepted for publication in this journal and posted online before print publication. Articles appearing here may contain statements, opinions, and information that have errors in facts, figures, or interpretation. Accordingly, Lippincott Williams & Wilkins, the editors and authors and their respective employees are not responsible or liable for the use of any such inaccurate or misleading data, opinion or information contained in the articles in this section.
Reynolds PQ, Sanders NW, Schildcrout JS, Mercaldo ND, St Jacques PJ: Expansion of the Surgical Apgar Score Across All Surgical Subspecialties as a Means to Predict Postoperative Mortality. Anesthesiology 2011
: A surgical scoring system, akin to the obstetrician’s Apgar score, has been developed to assess postoperative risk. To date, evaluation of this scoring system has been limited to general and vascular services. The authors attempt to externally validate and expand the Surgical Apgar Score across a wide breadth of surgical subspecialties.
: Intraoperative data for 123,864 procedures including all surgical subspecialties were collected and associated with Surgical Apgar Scores (created by the summation of point values associated with the lowest mean arterial pressure, lowest heart rate, and estimated blood loss). Patients’ death records were matched to the corresponding score, and logistic regression models were created in which mortality within 7, 30, and 90 days was regressed on the Apgar score.
: Lower Surgical Apgar Scores were associated with an increased risk of death. The magnitude of this association varied by subspecialty. Some subspecialties exhibited higher odds ratios, suggesting that the score is not as useful for them. For most of the subspecialties the association between the Apgar score and mortality decreased as the time since surgery increased, suggesting that predictive ability ceases to be helpful over time. After adjusting for the patient’s American Society of Anesthesiologists classification, Apgar scores remained associated with death among most of the subspecialties.
: A previously published methodology for calculating risk among general and vascular surgical patients can be applied across many surgical services to provide an objective means of predicting and communicating patient outcomes in surgery as well as planning potential interventions.