Abstract
Purpose
To determine the risk of unanticipated intraoperative events (UIE) in patients assessed at a preanaesthetic clinic compared with those not assessed at the clinic.
Methods
Preoperative and intraoperative data were collected on 6130 elective surgical patients by procedural anaesthetists over a 12-month period at an Australian tertiary referral hospital. The procedural anaesthetists rated the level of preparation and identified predefined unanticipated intraoperative events. A logistic regression model was used to identify significant risk factors of UIE and was further validated on another sample of 482 patients (one month) by a goodness-of-fit test.
Results
Of the 6130 elective surgical patients, 2000 (33%) had been assessed at the preanaesthetic clinic. There was a greater proportion of ASA II to IV patients seen at the clinic than patients not assessed at the clinic (χ2 3=689.92, P < 0.001). Nondinic patients were more likely to be inadequately prepared than clinic patients (RRunadjusted= 1.61, 95%Cl: 1.25 to 2.04. P < 0.001). The overall incidence of intraoperative events was 4.14% (95%Cl: 3.64% to 4.64%). Despite adjusting for the preparation level, type of anaesthesia, admission category, ASA physical status and duration of anaesthesia, clinic patients were 1.94 (95%Cl: 1.42 to 2.64) times more likely to experience an UIE than nondinic patients (P < 0.001).
Conclusion
Although clinic patients were more often optimally prepared, their adjusted risk of UIE was higher than nondinic patients. The procedural anaesthetist needs to be vigilant with these high risk patients, even if they have been assessed at a preanaesthetic clinic.
Résumé
Objectif
Préciser le risque d’incidents peropératoires imprévus chez les patients évalués en clinique préanesthésique comparativement à ceux qui n’y sont pas évalués.
Méthodes
Les données préoperatoires et peropératoires de 6 130 cas électifs ont été recueillies par des anesthésistes sur une période de 12 mois dans un hôpital australien spécialisé en soins tertiaires. Les anesthésistes ont évalué le degré de préparation et ont identifié des incidents peropératoire imprévus prédéfinis. Un modèle de régression logique a été utilisé pour identifier les facteurs irnportants de risque d’incidents imprévisibles et a été validé ultérieurement avec un autre échantillon de 482 patients (un mois) grâce à un test de corrélation.
Résultats
Deux milte des 6 130 patients électifs avaient été évalués à la clinique préanesthésique dont une proportion plus élevée de patients ASA II–IV (χ2 3=689,92, P < 0,001). Le manque de préparation survenait plus souvent chez les patients non évalués en clinique (RRnon ajusté = 1,61, 95% IC: 1,25 à 2,04, P < 0,001). L’incidence globale des incidents peropératoires était de 4,14% (95% IC: 3,64% à 4,64%). En dépit des ajustements accordés pour le degré de préparation, le type d’anesthésie, la catégone d’admission, l’état physique ASA et la durée de l’anesthésie, les patients vus en cliniques étaient 1,94 (95% IC: 1,42 à 2,64) fois plus sujets à subir un accident imprévu que les autres (P < 0,001).
Conclusion
Bien que les patients vus en clinique aient reçu plus souvent une préparation optimale, ils encouraient un risque plus élevé d’incidents imprévus que ceux qui n’y avaient pas été vus. L’anesthésiste se doit d’être vigilant devant ces patients à haut risque, même s’ils ont subi une évaluation dans une clinique préanesthésique.
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This study was supported, in part, by the Australian and New Zealand College of Anaesthetists Research Grant, Short Stay Surgery Research Institute and the Department of Anaesthetics, Liverpool Hospital.
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Lee, A., Lum, M.E., Perry, M. et al. Risk of unanticipated intraoperative events in patients assessed at a preanaesthetic clinic. Can J Anaesth 44, 946–954 (1997). https://doi.org/10.1007/BF03011966
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DOI: https://doi.org/10.1007/BF03011966