Preoperative anaesthesia triage with a patient-centred system—A prospective clinical study

Background: Increase in day surgery has challenged preoperative anaesthesia with need to identify a few high-risk patients requiring detailed preoperative intervention. We aimed to assess if a nurse-administered Preoperative Patient-centred Anaesthesia System (Pre-PAS) could identify high-risk patients, defined as ASA score III-IV, before surgery and allow triage in standard preanaesthesia care. We hypothesized that Pre-PAS ≥ 1 would identify ASA III-IV patients with high specificity. Methods: We conducted a prospective study, where twelve preoperative risk factors were recorded before surgery with the Pre-PAS questionnaire along with a score from zero to twelve based on the number of positive criteria. Only patients with a Pre-PAS score ≥ 1 were followed by mandatory preoperative anaesthetists' assessment visit. Medical records were reviewed to ensure accurate ASA score evaluation, surgical cancellations and airway difficulties. Association between Pre-PAS score and ASA score was evaluated by Fisher's exact test. Results: In a total of 487 included patients, 92% of high-risk patients (ASA III-IV) and 54% of low-risk patients (ASA I-II) had Pre-PAS score ≥ 1 (P ≤.001). Nine out of 12 Pre-PAS criteria were significantly associated with higher frequency in ASA III-IV. Pre-PAS reduced number of preanaesthetic visits by 39%. Pre-PAS ≥ 1 had a sensitivity of 0.92 and a specificity of 0.46 for ASA III-IV. Conclusions: A patient-centred preoperative triage system had high sensitivity for identifying ASA III-IV, and multiple Pre-PAS variables were associated with ASA III-IV, but the model had low specificity. Pre-PAS may guide triage of relevant patients to preanaesthetic visit.