Evaluation of volume status in a prehospital setting by ultrasonographic measurement of inferior vena cava and aorta diameters

Objectives: The aim of this study was to evaluate the utility of ultrasonographic measurement of the diameter of the inferior vena cava (IVCD) and abdominal aorta (AAD) for assessing volume status. Material and methods: This was a prospective, observational study. A total of 23 volunteers participated in the study. Each participant was selected randomly. All participants completed the 2016 Kaunas Marathon. Participants filed out a brief survey about their fluid intake (in standardised glasses) in the 24 h before the race and during the race. Participants underwent ultrasound measurements 10–40 min before the start of the race and 3–15 min after finishing the race. To visualize respiratory variation, M-mode was used, with the beam crossing the IVCD 2 cm from the right atrium. The AAD was measured 1 cm above the celiac trunk. IVCD in expiration (IVCDexp)/AAD was calculated by dividing the value of IVCDexp by the value of AAD. The findings were compared with difference in body mass index. Results: The mean weight lost after the marathon was 2.93 kg (p < 0.001). Mean IVCD in inspiration (IVCDins) after the run was lower by 0.39 cm (p < 0.001) then before the run. Mean IVCDexp/AAD after the run was 0.24 cm lower than before the run (p = 0.03). Before and after the marathon, there was a statistically significant negative correlation in weight difference, with mean IVCDexp difference (p = 0.047). There was no statistically significant difference in caval index before and after running. Conclusion: Ultrasonographic assessment of IVCDexp could be useful in the evaluation of volume status. Keywords: Hypovolemic shock, Inferior vena cava, Abdominal aorta, Ultrasoun

Short- and long-term survival after out-of-hospital cardiac arrest in Kaunas (Lithuania) from 2016 to 2018

Abstract Background No studies analysing out-of-hospital cardiac arrest (OHCA) epidemiology and outcomes in Lithuania were published in the last decade. Methods We conducted a retrospective analysis of prospectively collected data. The incidence of OHCA and the demographics and outcomes of patients who were treated for OHCA between 1 and 2016 and 31 December 2018 at Kaunas Emergency Medical Service (EMS) were collected and are reported in accordance with the Utstein recommendations. Multivariable logistic regression analysis was used to identify predictors of survival to hospital discharge. Results In total, 838 OHCA cases of EMS-treated cardiac arrest (CA) were reported (95.8 per 100.000 inhabitants). The median age was 71 (IQR 58–81) years of age, and 66.7% of patients were males. A total of 73.8% of OHCA cases occurred at home, 59.3% were witnessed by a bystander, and 54.5% received bystander cardiopulmonary resuscitation. The median EMS response time was 10 min. Cardiac aetiology was the leading cause of CA (78.8%). The initial rhythm was shockable in 27.6% of all cases. Return of spontaneous circulation at hospital transfer was evident in 24.9% of all cases. The survival to hospital discharge rate was 10.9%, and the 1-year survival rate was 6.9%. The survival to hospital discharge rate in the Utstein comparator group was 36.1%, and the 1-year survival rate was 27.2%. Five factors were associated with improved survival to hospital discharge: shockable rhythm, time from call to arrival at the patient less than 10 min, witnessed OHCA, age < 80 years, and male sex. Conclusion This is the first OHCA study from Lithuania examining OHCA epidemiology and outcomes over a three year period. Routine OHCA data collection and analysis will allow us to track the efficacy of service improvements and should become a standard practice in all Lithuanian regions. Trial registration: This research was registered in the clinicaltrials.gov database: Identifiers: NCT04784117, Unique Protocol ID: LITOHCA. Brief Title: Out-of-hospital Cardiac Arrest Epidemiology and Outcomes in Kaunas 2016–2021

Cavitation dynamics and directional microbubble ejection induced by intense femtosecond laser pulses in liquids

We study cavitation dynamics when focusing ring-shaped femtosecond laser beams in water. This focusing geometry reduces detrimental nonlinear beam distortions and enhances energy deposition within the medium, localized at the focal spot. We observe remarkable postcollapse dynamics of elongated cavitation bubbles with high-speed ejection of microbubbles out of the laser focal region. Bubbles are ejected along the laser axis in both directions (away and towards the laser). The initial shape of the cavitation bubble is also seen to either enhance or completely suppress jet formation during collapse. In the absence of jetting, microbubble ejection occurs orthogonal to the laser propagation axis