Aims An increase in out-of-hospital cardiac arrest (OHCA) incidence has been reported in the very early phase of the COVID-19 epidemic, but a clear demonstration of a correlation between the increased incidence of OHCA and COVID-19 is missing so far. We aimed to verify whether there is an association between the OHCA difference compared with 2019 and the COVID-19 epidemic curve. Methods and results We included all the consecutive OHCAs which occurred in the Provinces of Lodi, Cremona, Pavia, and Mantova in the 2 months following the first documented case of COVID-19 in the Lombardia Region and compared them with those which occurred in the same time frame in 2019. The cumulative incidence of COVID-19 from 21 February to 20 April 2020 in the study territory was 956 COVID-19/100 000 inhabitants and the cumulative incidence of OHCA was 21 cases/100 000 inhabitants, with a 52% increase as compared with 2019 (490 OHCAs in 2020 vs. 321 in 2019). A strong and statistically significant correlation was found between the difference in cumulative incidence of OHCA between 2020 and 2019 per 100 000 inhabitants and the COVID-19 cumulative incidence per 100 000 inhabitants both for the overall territory (ρ 0.87, P < 0.001) and for each province separately (Lodi: ρ 0.98, P < 0.001; Cremona: ρ 0.98, P < 0.001; Pavia: ρ 0.87, P < 0.001; Mantova: ρ 0.81, P < 0.001). Conclusion The increase in OHCAs in 2020 is significantly correlated to the COVID-19 pandemic and is coupled with a reduction in short-term outcome. Government and local health authorities should seriously consider our results when planning healthcare strategies to face the epidemic, especially considering the expected recurrent outbreaks.

Background and Purpose— Cerebral blood flow (CBF) reduction below critical thresholds discriminates between irreversible infarct core, penumbra, and benign oligemia (penumbra that recovers spontaneously). Thresholds are based on animal studies, and their diagnostic accuracy in humans has never been established. The purpose of this study was to assess the evidence available on CBF thresholds for infarct core and penumbra in adult stroke patients. Methods— Electronic database searching using Medline, Embase and the Cochrane Library, crosschecking of references, and contact with experts and authors of primary studies was used. Studies on adult stroke patients were included if they compared CBF measurements with a diagnostic gold standard (follow-up brain CT/MRI), and reported CBF thresholds. Two reviewers independently extracted the data and assessed study quality. Results— A meta-analysis could not be carried out because of insufficient data. The optimal reported CBF thresholds varied widely, from 14.1 to 35.0 and from 4.8 to 8.4 mL/100 g per minute for penumbra and infarct core, respectively. Conclusions— The use of CBF thresholds in commercial software for imaging methods cannot be recommended without further evaluation.

Basic and clinical research is unraveling the pathophysiological mechanisms of critical illness myopathy and polyneuropathy, and methods for rapid diagnosis are actively investigated. Future studies should better define the population at risk of developing CIM and CIP. In fact, although sepsis, multi-organ failure and steroids are often cited as risk factors, uncertainty remains due to the poor methodological quality of studies, or because of inferences that are exclusively based on animal studies. New simplified diagnostic techniques and machines for electrophysiological investigations of peripheral nerves and muscles in the intensive-care unit (ICU) patient would also be welcome.