Purpose：This study investigated the droplets released during coughing. We aimed to visualize aerosol generation during cough that causes changes in intrathoracic pressure, significantly increasing chest compressions, and to examine the effect on the amount of droplets associated with coughing using improved pocket masks. Methods：The participants included 10 college students. We compared the amount of cough droplets status under three conditions using pocket masks. Results：In addition to the pocket masks, a vinyl cover could be used to cover the head and a HEPA filter to suppress the droplets from the victim (p <0.01). Conclusion：The use of pocket masks may reduce the risk of droplet infection.

Objective：To evaluate patient- and prefecture-level the association between adrenaline administration time (the patient-contact to first adrenaline administration interval) and a favorable neurological outcome (CPC1-2).

Method：A retrospective cohort study was conducted using the All-Japan Utstein Registry between 2015 and 2019. We included patients aged ≥ 18 years for whom adrenaline administration in the prehospital setting (Shockable, n = 11,615；Non-shockable, n = 113,962). The multilevel logistic regression estimated the adjusted odds ratio (AOR) and 95% confidence interval (CI) for patient and prefecture-level the association between adrenaline administration time in (1-minute increment) and CPC1-2.

Result：In the Shockable and Non-shockable cohorts, a delay of adrenaline administration time in patient and prefecture-level negatively associated with CPC1-2.

Conclusion：We found that a delay in adrenaline administration in patient and prefecture level showed a negative association with CPC1-2.

The success rate of the procedure and time spent at the scene were calculated for cases in which prehospital intravenous catheter insertion was considered for shock patients from the Kobe City Fire Department database. The success rate was 80% for those with exogeneous illness and 70% for those with endogenous illness, and was significantly higher for those with exogenous illness. In addition, the time spent at the scene was not prolonged in patients with exogenous illness when comparing the success rate with the failure rate. In Kobe, prehospital care intervened more frequently in cases of exogenous shock, whereas most of the injuries and illnesses that required paramedics to respond before arrival at the hospital were of internal origin. Since the results and problems are expected to be diverse depending on regional characteristics, data should be actively presented for each region.

Shockindex (S.I.) ≧1 is important as an indicator of bleeding in cases of injury.According to the guidelines for management of critical bleeding in obstetrics,it is recommended to be used as a reliable marker of hemorrhage in case of bothtransvaginal and caesarean deliveries. Despite that, some studies reported therelation of hemorrhage and S.I. only in transvaginal delivery ; there may notbe enough evidence for caesarean delivery. It may be because there are manyfactors that affect vital signs such as anesthesia, vasopressors, andtransfusion used during caesarean section. Thus, the utility of S.I. is stillunclear in caesarean section. We reviewed three cases of massive obstetricbleeding ( > 2000 mL) in our hospital, and the relation between S.I. andhemorrhage was analyzed. In all of the three cases, hypotension and S.I. ≧ 1were observed owing to bleeding. S.I. remained ≧ 1 until hemostasis, but afterhemostasis, S.I. declined promptly and tended to be < 1. These cases suggestthat S.I. ≧ 1 could be a reliable indicator of massive bleeding during cesareansection.