ECG changes after non-cardiac surgery: a prospective observational study in intermediate-high risk patients

Correlation between heart rate variability and perioperative neurocognitive disorders in patients undergoing non-cardiac surgery: A retrospective cohort study

OBJECTIVE

With the improvement of medical level, the number of elderly patients is increasing, and the postoperative outcome of the patients cannot be ignored. However, there have been no studies on the relationship between preoperative heart rate variability (HRV) and Perioperative Neurocognitive Disorders (PND). The purpose of this study was to explore the correlation between (HRV) and (PND), postoperative intensive care unit (ICU), and hospital stay in patients undergoing non-cardiac surgery.

METHOD

This retrospective analysis included 687 inpatients who underwent 24-hour dynamic electrocardiogram examination in our six departments from January 2021 to January 2022. Patients were divided into two groups based on heart rate variability (HRV): high and low. Possible risk factors of perioperative outcomes were screened using univariate analysis, and risk factors were included in multivariate logistic regression to screen for independent risk factors. The subgroup analysis was carried out to evaluate the robustness of the results. The nomogram of PND multi-factor logistic prediction model was constructed. The receiver operating characteristic (ROC) curve was drawn, and the calibration curve was drawn by bootstrap resampling 1000 times for internal verification to evaluate the prediction ability of nomogram.

RESULT

A total of 687 eligible patients were included. The incidence of low HRV was 36.7% and the incidence of PND was 7.6%. The incidence of PND in the low HRV group was higher than that in the high HRV group (11.8% vs 5.2%), the postoperative ICU transfer rate was higher (15.9% than 9.3%P = 0.009), and the hospital stay was longer [15 (11, 19) vs (13), 0.015]. The multivariable logistic regression analysis showed that after adjusting for other factors, decreased low HRV was identified as an independent risk factor for the occurrence of PND (Adjusted Odds Ratio = 2.095; 95% Confidence Interval: 1.160-3.784; P = 0.014) and postoperative ICU admission (Adjusted Odds Ratio = 1.925; 95% Confidence Interval: 1.128-3.286; P = 0.016). This study drew a nomogram column chart for a multivariate logistic regression model, incorporating age and HRV. The calibration curve shows that the predicted value of the model for the occurrence of cardio-cerebrovascular events is in good agreement with the actual observed value, with C-index of 0.696 (95% CI: 0.626 ~ 0.766). Subgroup analysis showed that low HRV was an independent risk factor for PND in patients with gastrointestinal surgery and ASA Ⅲ, aged ≥ 65 years.

CONCLUSION

In patients undergoing non-cardiac surgery, the low HRV was an independent risk factor for PND and postoperative transfer to the ICU, and the hospitalization time of patients with low HRV was prolonged. Through establishing a risk prediction model for the occurrence of PND, high-risk patients can be identified during the perioperative period for early intervention.

Can Orthopaedic Surgeons adequately assess an Electrocardiogram (ECG) trace paper? A cross sectional study

Objectives

The primary objective was to evaluate the ECG trace paper evaluation current knowledge level in a group of Orthopaedic surgeons divided into juniors and seniors according to M.D. degree possession.

Methods

A cross sectional study through self-administered questionnaires at a university hospital Orthopaedic and Trauma Surgery Department. The questionnaire included five sections: 1-Basic participants' characteristics, 2-Participants' perception of their ECG evaluation current knowledge level, 3-The main body of the questionnaire was an ECG quiz (seven); the participant was asked to determine if it was normal and the possible diagnosis, 4-Participants' desired ECG evaluation knowledge level, and 5-Willingness to attend ECG evaluation workshops.

Results

Of the 121 actively working individuals in the department, 96 (97.3 %) finished the questionnaire, and 85 (77.3 %) were valid for final evaluation. The participants' mean age was 30.4 ± 6.92 years, 76.5 % juniors and 23.5 % seniors. 83.5 % of the participants perceived their current ECG evaluation knowledge as none or limited. For participants' ability to evaluate an ECG, higher scores were achieved when determining if the ECG was normal or abnormal, with a mean score percentage of 79.32 % ± 23.27. However, the scores were lower when trying to reach the diagnosis, with a mean score percentage of 43.02 % ± 27.48. There was a significant negative correlation between the participant's age and answering the normality question correctly (r = -0.277, p = 0.01); and a significant positive correlation between answering the diagnosis question correctly and the desired level of knowledge and the intention to attend a workshop about ECG evaluation, r = 0.355 (p = 0.001), and r = 0.223 (p = 0.04), respectively. Only 56.5 % of the participants desired to get more knowledge, and 81.2 % were interested in attending ECG evaluation workshops.

Conclusion

Orthopaedic surgeons showed sufficient knowledge when determining the normality of ECG trace papers; however, they could not reach the proper diagnosis, and Junior surgeons performed slightly better than their senior peers. Most surgeons are willing to attend ECG evaluation and interpretation workshops to improve their knowledge level.