ASA classification

from Wikipedia, the free encyclopedia

The ASA classification is a widely used scoring system in medicine for classifying patients according to their physical condition (ASA PS: ASA Physical Status). The in May 1941 by Saklad et al. The classification proposed by the American Society of Anesthesiologists (ASA) under the title Grading of Patients for Surgical Procedures allocates patients to different risk groups based on systemic diseases before anesthesia, is published annually by the ASA and is currently:

  • ASA 1: Normal, otherwise healthy patient
  • ASA 2: patient with mild general disease
  • ASA 3: patient with severe general illness
  • ASA 4: patient with severe general illness that is a constant threat to life
  • ASA 5: moribund (terminally ill) patient who is unlikely to survive without the operation
  • ASA 6: brain-dead patient whose organs are removed for organ donation

Furthermore, the additional designation E (emergency) is added to the classes for emergency interventions. In this case, there is an emergency if a delay in treatment results in a significant increase in the risk to life for the patient or for a part of the body. The ASA classification is used to estimate the severity of the disease, to assess the course and to control therapy, represents an independent risk factor for postoperative morbidity and lethality and plays v. a. in the United States has a role in the financial regulation of the health system.

A major problem of the ASA classification is the subjectivity of the assessment, which manifests itself in only a small degree of agreement (30–80%) if different anesthesiologists are asked to classify the same patient. Since in addition to the ASA classification, various other factors such as a. If the age, type and duration of the surgical procedure, the quality of the surgeon and anesthetist, material equipment and postoperative follow-up care all influence the perioperative risk, the classification alone is unsuitable for making a prognosis for the outcome of the operation or for assessing the complication rate of a hospital as part of quality assurance assess what the original authors around Saklad were already aware of in 1941. The assessment of the surgical risk, which can be increased by coronary heart disease , chronic kidney failure or diabetes , is not the meaning of the ASA score, but rather this score is intended to give a general assessment of the patient's status, which is easy to process statistically and be applicable in any situation.

history

In 1940/41 the ASA commissioned a committee of three doctors (Meyer Saklad, Emery Rovenstine and Ivan Taylor) to research, test and implement a system that would allow the collection and tabulation of statistical data in anesthesiology and among all Circumstances could be used. This was the first effort by a medical specialty to stratify the risks for its patients. Although their job was to find predictors of operational risk, they declined because it would be impossible to do. They said:

In attempting to standardize and define what has heretofore been considered 'Operative Risk', it was found that the term ... could not be used. It was felt that for the purposes of the anesthesia record and for any future evaluation of anesthetic agents or surgical procedures, it would be best to classify and grade the patient in relation to his physical status only. "

So the scale they suggested took into account the preoperative "physical status" of the patient alone, without considering the operation or other factors that could affect the outcome. The authors hoped that anesthesiologists from all parts of America would adopt this “common terminology” and thus make statistical statements about morbidity and mortality possible by comparing the results of surgery and the patient's preoperative condition.

They described a six-class score, from a healthy patient (class 1) to one with extreme systemic dysfunction that poses an imminent threat to the patient's life (class 4). The first four classes roughly corresponded to today's ASA classes 1 to 4, emergencies in classes 1 and 2 as well as 3 and 4 were recorded in emergency classes 5 and 6, respectively. Class 6 was added between 1941 and 1961. In 1963 two changes were made. Firstly, grades 5 and 6 were dropped and a new grade 5 was added (see above). Second, the emergency classes have simply been replaced with an “E” modifier for the remaining classes. In 1980, a sixth grade for brain-dead organ donors was added.

Saklad gave examples for each class to promote uniformity. Unfortunately, the ASA did not later include such examples in its classification, adding to the confusion. This fact led to criticism of the classification, which might not have been necessary.

Original text from 1941 (with translation)

The original classification from 1941 still contained a few examples of how the classification was handled and divided:

class original translation
Class 1. No organic pathology or patients in whom the pathological process is localized and does not cause any systemic disturbance or abnormality.

Examples: This includes patients suffering with fractures unless shock, blood loss, emboli or systemic signs of injury are present in an individual who would otherwise fall in Class 1. It includes congenital deformities unless they are causing systemic disturbance. Infections that are localized and do not cause fever, many osseous deformities, and uncomplicated hernias are included. Any type of operation may fall in this class since only the patient's physical condition is considered.

No organic pathology or patients in whom the pathological processes are localized and do not cause systemic disturbances or abnormalities.

Examples: This includes patients with broken bones , except when there is shock , blood loss, embolism, or systemic signs of injury in a person who would otherwise be in Class 1. This includes congenital deformities, except when they cause systemic disorders. Infections that are localized and do not cause fever, many bony deformations and uncomplicated hernias are also included. Any type of surgery can fall into this class because only physical condition is taken into account.

Class 2. A moderate but definite systemic disturbance, caused either by the condition that is to be treated or surgical intervention or which is caused by other existing pathological processes, forms this group.

Examples: Mild diabetes. Functional capacity I or IIa. Psychotic patients unable to care for themselves. Mild acidosis. Anemia moderate. Septic or acute pharyngitis. Chronic sinusitis with postnasal discharge. Acute sinusitis. Minor or superficial infections that cause a systemic reaction. (If there is no systemic reaction, fever, malaise, leukocytosis, etc., aid in classifying.) Nontoxic adenoma of thyroid that causes but partial respiratory obstruction. Mild thyrotoxicosis. Acute osteomyelitis (early). Chronic osteomyelitis. Pulmonary tuberculosis with involvement of pulmonary tissue insufficient to embarrass activity and without other symptoms.

A moderate but defined systemic disorder caused either by the condition to be treated by the surgical procedure or by other pathological processes forms this group.

Examples: Mild diabetes mellitus , functional capacity I or IIa, psychotic patients who cannot take care of themselves, mild acidosis , moderate anemia , septic or acute pharyngitis , chronic sinusitis with postnasal discharge, acute sinusitis, minor or superficial infections that have a systemic reaction cause (if no systemic reaction is visible, fever , malaise, leukocytosis , etc. can help with the classification), non-toxic adenoma of the thyroid gland which only slightly restricts the airways, mild thyrotoxicosis , acute osteomyelitis , pulmonary tuberculosis with involvement of the lung tissue, non- sufficient to produce activity and without other symptoms.

Class 3. Severe systemic disturbance from any cause or causes. It is not possible to state an absolute measure of severity, as this is a matter of clinical judgment. The following examples are given as suggestions to help demonstrate the difference between this class and Class 2.

Examples: Complicated or severe diabetes. Functional capacity IIb. Combinations of heart disease and respiratory disease or others that severely impair normal functions. Complete intestinal obstruction that has existed long enough to cause serious physiological disturbance. Pulmonary tuberculosis that, because of the extent of the lesion or treatment, has induced vital capacity sufficiently to cause tachycardia or dyspnea. Patients debilitated by prolonged illness with weakness of all or several systems. Severe trauma from accident resulting in shock, which may be improved by treatment. Pulmonary abscess.

Severe systemic disorders from any cause. It is not possible to give an absolute measure of severity as it is a matter of clinical judgment. The following examples, as suggestions, will help demonstrate the difference between this class and class 2.

Examples : Complicated or severe diabetes mellitus, functional capacity IIb. Combinations of heart disease and respiratory disease or other conditions that severely affect normal function. Complete bowel obstruction that has persisted long enough to cause serious physiological disorders. Pulmonary tuberculosis, which causes tachycardia or dyspnea due to the size of the lesions or the treatment . Patients who suffer from weakness in all or several systems due to a long illness. Severe trauma from accident in shock, which treatment can improve. Lung abscess .

Class 4. Extreme systemic disorders which have already become an eminent threat to life regardless of the type of treatment. Because of their duration or nature there has already been damage to the organism that is irreversible. This class is intended to include only patients that are in an extremely poor physical state. There may not be much occasion to use this classification, but it should serve a purpose in separating the patient in very poor condition from others.

Examples: Functional capacity III - (Cardiac Decompensation). Severe trauma with irreparable damage. Complete intestinal obstruction of long duration in a patient who is already debilitated. A combination of cardiovascular-renal disease with marked renal impairment. Patients who must have anesthesia to arrest a secondary hemorrhage where the patient is in poor condition associated with marked loss of blood. Emergency Surgery: An emergency operation is arbitrarily defined as a surgical procedure which, in the surgeon's opinion, should be performed without delay.

Extreme systemic diseases that are already life threatening regardless of the type of treatment. By their duration or nature, they have already caused irreversible damage. This class is only intended for patients who are in very poor condition. There are probably not many opportunities to use this classification, but it is intended to separate patients in very poor condition from others.

Examples: Functional capacity III (decompensation of the heart), severe trauma with irreversible damage, complete intestinal obstruction over a long period of time during which the patient is already exhausted, a combination of heart and kidney disease with significant kidney failure, patients who are placed under anesthesia have to have emergency surgery to stop secondary bleeding where the patient is already in poor condition from the loss of blood. Emergency surgery is arbitrarily defined as any surgical procedure that the surgeon believes must be performed immediately.

Class 5. Emergencies that would otherwise be graded in Class 1 or Class 2. Emergencies that would otherwise be classified in class 1 or 2.
Class 6. Emergencies that would otherwise be graded as Class 3 or Class 4. Emergencies that would otherwise be classified in class 3 or 4.

credentials

  1. ^ American Society of Anesthesiologists: ASA Physical Status Classification System. ASA, October 15, 2014, accessed June 19, 2018 .
  2. ↑ Hackett NJ et al .: ASA class is a reliable independent predictor of medical complications and mortality following surgery . Ed .: International Journal of Surgery. tape 18 (2015) , April 26, 2015, p. 184-190 .
  3. ↑ Little JP: Consistency of ASA grading . In: Anaesthesia . 50, No. 7, 1995, pp. 658-9. PMID 7653772 .
  4. ^ Haynes SR, Lawler PG: An assessment of the consistency of ASA physical status classification allocation . In: Anaesthesia . 50, No. 3, 1995, pp. 195-9. doi : 10.1111 / j.1365-2044.1995.tb04554.x . PMID 7717481 .
  5. ↑ Owens WD, Felts JA, Spitznagel EL: ASA physical status classification: A study of consistency of ratings . In: Anaesthesia . 49, 1978, pp. 239-43. PMID 697077 .
  6. ↑ Harling DW: Consistency of ASA Grading . In: Anaesthesia . 50, No. 7, p. 659. PMID 7653773 .
  7. ↑ a b c Saklad M. Grading of patients for surgical procedures. Anesthesiology 1941; 2: 281-4.
  8. ↑ Wolfgang Eichler, Anja Voß: Operative Intensive Care Medicine. In: Jörg Braun, Roland Preuss (Ed.): Clinic Guide Intensive Care Medicine. 9th edition. Elsevier, Munich 2016, ISBN 978-3-437-23763-8 , pp. 619-672, here: pp. 630 f. ( Operative risk patients ).
  9. ↑ Spell, Nathan O .; Lubin, Michael F .; Smith, Robert Metcalf; Dodson, Thomas F: Medical Management of the Surgical Patient: A Textbook of Perioperative Medicine . Cambridge University Press, Cambridge, UK 2006, ISBN 0-521-82800-7 .
  10. ^ Mark J Lema: Using the ASA Physical Status Classification May Be Risky Business . In: ASA Newsletter . American Society of Anesthesiologists. September 2002. Retrieved July 9, 2007.
  11. ^ A b Scott Segal: Women Presenting in Labor Should be Classified as ASA E: Pro . In: Winter 2003 newsletter . SOAP. Retrieved July 9, 2007.
  12. ↑ Irlbeck T et al .: ASA classification . In: Anaesthesiologist . tape 66 (1) , January 2017, p. 5-10 , doi : 10.1007 / s00101-016-0246-4 .
  13. ^ New classification of physical status. Anesthesiology 1963; 24: 111

literature