Peri-operative cardiac arrests in Sweden 2013–2022: data analysis of incidence and trends

Abstract

In Europe, out-of-hospital cardiac arrests have an annual incidence rate of 7–17/10,000 per capita and in-hospital cardiac arrests have an annual incidence rate of 15–28/10,000 hospital admissions [1]. The incidence of in-hospital cardiac arrests in Sweden is 16/10,000 hospital admissions [2]. We conducted a study assessing if the incidence of peri-operative cardiac arrest had decreased in Sweden from 2013 to 2022. We also assessed the association between 30-day mortality, patient characteristics and urgency of surgery. All patients aged ≥ 18 y experiencing peri-operative cardiac arrest in the Swedish Perioperative Register (SPOR) between January 2013 and June 2022 were included. Total number of surgical procedures with complete data for patients aged ≥ 18 y registered in SPOR from 2013 to 2022 was used as the denominator (n = 3,049,782).

The primary outcome was the incidence of peri-operative cardiac arrest in 2022 compared with 2013. Secondary outcomes were 30-day all-cause mortality and association of peri-operative cardiac arrest with patient characteristics and urgency. Descriptive and regression analysis was performed. In total, 749 patients (51.6% male, mean (SD) age 69 (17.4) y) experienced peri-operative cardiac arrest during the study period. Patient characteristics and urgency are presented in Table 1. Year was missing for 13 cases of peri-operative cases leaving 736 for analysis. This equates to an overall annual incidence of peri-operative cardiac arrest of 2.4/10,000 procedures (95%CI 2.2–2.6). There was no significant difference over the period studied: 2.9/10,000 procedures in 2013 vs. 1.8/10,000 procedures in 2022. The highest incidence of peri-operative cardiac arrest and highest 30-day mortality rate was seen in patients who underwent emergency surgeries (54%). Hip fracture surgery was the most common planned surgical intervention, (n = 120, 16%) during the study period, followed by abdominal surgery (n = 118, 16%). 30-day mortality following cardiac arrest was 48% and mortality rate was 1.2/10,000 procedures (95%CI 0.7–1.5). Odds ratio (OR) for 30-day mortality increased with age (65–80 y, OR 2.32 (95%CI 1.43–3.77), > 80 y, OR 6.11 (95%CI 3.57–10.45)); ASA physical status 3–5 (OR 2.81 (95%CI 1.74–4.54)); and surgical urgency (emergent OR 2.89 (95%CI 1.85–4.51), immediate 9.20 (95%CI 4.80–17.65)) but showed no significant change over time when adjusted for co-factors.

The overall incidence of peri-operative cardiac arrest in Sweden among adult patients (2.4 per 10,000 procedures) is lower compared with previous studies which ranged between 3–7 per 10,000 [3, 4]. A recent UK study found incidence rates of 3.0–3.5 per 10,000 interventions [4]. In that cohort, however, patients from infancy up to age 18 y (n = 12%) were included in the study. The Royal College of Anaesthetists, in its updated National Audit project (NAP7), defined peri-operative cardiac arrest as “the delivery of five or more compressions and/or defibrillation in a patient having a procedure under the care of an anaesthetist” [5]. The SPOR register includes only peri-operative events and cardiac arrest during the recovery room stay. It should also be acknowledged that the available data did not include medical history, information about comorbidities nor any detailed information about the cardiac arrest. It is reassuring to see that peri-operative cardiac arrest incidence is in line with data from other register studies, which show mortality rates around 50–60% [3].