Long-term outcomes after out-of-hospital cardiac arrest: A systematic review and meta-analysis.

AIMS: Long term outcomes after out-of-hospital cardiac arrest (OHCA) are not well understood. This study aimed to evaluate the long-term (1-year and beyond) survival outcomes, including overall survival and survival with favorable neurological status and the quality-of-life (QOL) outcomes, among patients who survived the initial OHCA event (30 days or till hospital discharge). METHODS: Embase, Medline and PubMed were searched for primary studies (randomized controlled trials, cohort and cross-sectional studies) which reported the long-term survival outcomes of OHCA patients. Data abstraction and quality assessment was conducted, and survival at predetermined timepoints were assessed via single-arm meta-analyses of proportions, using generalized linear mixed models. Comparative meta-analyses were conducted using the Mantel-Haenszel Risk Ratio (RR) estimates, using the DerSimonian and Laird model. RESULTS: 67 studies were included, and among patients that survived to hospital discharge or 30-days, 77.3% (CI = 71.2-82.4), 69.6% (CI = 54.5-70.3), 62.7% (CI = 54.5-70.3), 46.5% (CI = 32.0-61.6), and 20.8% (CI = 7.8-44.9) survived to 1-, 3-, 5-, 10- and 15-years respectively. Compared to Asia, the probability of 1-year survival was greater in Europe (RR = 2.1, CI = 1.8-2.3), North America (RR = 2.0, CI = 1.7-2.2) and Oceania (RR = 1.9, CI = 1.6-2.1). Males had a higher 1-year survival (RR:1.41, CI = 1.25-1.59), and patients with initial shockable rhythm had improved 1-year (RR = 3.07, CI = 1.78-5.30) and 3-year survival (RR = 1.45, CI = 1.19-1.77). OHCA occurring in residential locations had worse 1-year survival (RR = 0.42, CI = 0.25-0.73). CONCLUSION: Our study found that up to 20.8% of OHCA patients survived to 15-years, and survival was lower in Asia compared to the other regions. Further analysis on the differences in survival between the regions are needed to direct future long-term treatment of OHCA patients.

Heart rate n-variability (HRnV) measures for prediction of mortality in sepsis patients presenting at the emergency department.

Sepsis is a potentially life-threatening condition that requires prompt recognition and treatment. Recently, heart rate variability (HRV), a measure of the cardiac autonomic regulation derived from short electrocardiogram tracings, has been found to correlate with sepsis mortality. This paper presents using novel heart rate n-variability (HRnV) measures for sepsis mortality risk prediction and comparing against current mortality prediction scores. This study was a retrospective cohort study on patients presenting to the emergency department of a tertiary hospital in Singapore between September 2014 to April 2017. Patients were included if they were above 21 years old and were suspected of having sepsis by their attending physician. The primary outcome was 30-day in-hospital mortality. Stepwise multivariable logistic regression model was built to predict the outcome, and the results based on 10-fold cross-validation were presented using receiver operating curve analysis. The final predictive model comprised 21 variables, including four vital signs, two HRV parameters, and 15 HRnV parameters. The area under the curve of the model was 0.77 (95% confidence interval 0.70-0.84), outperforming several established clinical scores. The HRnV measures may have the potential to allow for a rapid, objective, and accurate means of patient risk stratification for sepsis severity and mortality. Our exploration of the use of wealthy inherent information obtained from novel HRnV measures could also create a new perspective for data scientists to develop innovative approaches for ECG analysis and risk monitoring.