The effects of Asian summer monsoon on algal blooms in reservoirs

An important characteristic of lakes and reservoirs in the East Asian summer monsoon region is the dramatic seasonal difference in hydrologic inputs, with annual rainfall commonly concentrated in a few heavy rain events. In this study, we surveyed the monthly variations of phytoplankton density in 3 large deep reservoirs and 7 small shallow reservoirs and analyzed the effect of large precipitation events on phytoplankton. During heavy rains, stream phosphorus concen¬trations increased sharply, and phosphorus loadings into reservoirs were not continuous but episodic shock loadings. In deep stratified reservoirs, however, the concentrations of phosphorus and chlorophyll a were much lower than expected from the high total phosphorus levels in the storm runoff. Inflowing storm waters laden with phosphorus flowed into metalimnetic layers because deep reservoirs had strong thermal stratification and the storm water was cooler than the epilimnion. The result was the formation of an ecosystem resilient to phosphorus shock loadings during monsoon. Nutrients in the metalimnion seemed to be dispersed gradually toward the epilimnion, and phytoplankton reached maximum densities, called “monsoon blooms,” after the monsoon. By contrast, shallow reservoirs with short hydraulic residence times had lower chlorophyll a concentrations during the monsoon season because the high flushing rate was the major limiting factor of phytoplankton growth. In conclusion, summer monsoon is the major determinant of phyto¬plankton density in reservoirs of the East Asian region, but their responses can vary widely depending on hydrologic characteristics

Impact of COVID-19 Pandemic on Management and Outcomes in Patients with Septic Shock in the Emergency Department

This study aimed to determine the impact of modifications in emergency department (ED) practices caused by the coronavirus disease 2019 (COVID-19) pandemic on the clinical outcomes and management of patients with septic shock. We performed a retrospective study. Patients with septic shock who presented to the ED between 1 January 2018 and 19 January 2020 were allocated to the pre-COVID-19 group, whereas those who presented between 20 January 2020 and 31 December 2020 were assigned to the post-COVID-19 group. We used propensity score matching to compare the sepsis-related interventions and clinical outcomes. The primary outcome measure was in-hospital mortality. Of the 3697 patients included, 2254 were classified as pre-COVID-19 and 1143 as postCOVID-19. A total of 1140 propensity score-matched pairings were created. Overall, the in-hospital mortality rate was 25.5%, with no statistical difference between the pre- and post-COVID-19 groups (p = 0.92). In a matched cohort, the post-COVID-19 group had delayed lactate measurement, blood culture test, and infection source control (all p < 0.05). There was no significant difference in time to antibiotics (p = 0.19) or vasopressor administration (p = 0.09) between the groups. Although sepsis-related interventions were delayed during the COVID-19 pandemic, there was no significant difference in the in-hospital mortality between the pre- and post-COVID-19 groups.Y

Impact of COVID-19 Pandemic on Management and Outcomes in Patients with Septic Shock in the Emergency Department

This study aimed to determine the impact of modifications in emergency department (ED) practices caused by the coronavirus disease 2019 (COVID-19) pandemic on the clinical outcomes and management of patients with septic shock. We performed a retrospective study. Patients with septic shock who presented to the ED between 1 January 2018 and 19 January 2020 were allocated to the pre-COVID-19 group, whereas those who presented between 20 January 2020 and 31 December 2020 were assigned to the post-COVID-19 group. We used propensity score matching to compare the sepsis-related interventions and clinical outcomes. The primary outcome measure was in-hospital mortality. Of the 3697 patients included, 2254 were classified as pre-COVID-19 and 1143 as post-COVID-19. A total of 1140 propensity score-matched pairings were created. Overall, the in-hospital mortality rate was 25.5%, with no statistical difference between the pre- and post-COVID-19 groups (p = 0.92). In a matched cohort, the post-COVID-19 group had delayed lactate measurement, blood culture test, and infection source control (all p < 0.05). There was no significant difference in time to antibiotics (p = 0.19) or vasopressor administration (p = 0.09) between the groups. Although sepsis-related interventions were delayed during the COVID-19 pandemic, there was no significant difference in the in-hospital mortality between the pre- and post-COVID-19 groups