Pre-hospital critical care management of severe hypoxemia in victims of Covid-19: a case series

Safety Assessment of Low-Flow Oxygenation Device: Quasi-Experimental Study

The objective of this study was to verify the feasibility of using an Oxygenation Device with Reservoir and Positive End-Expiratory Pressure (ODRPEEP; DORPEEP in Spanish) and to analyze its safety with respect to mask leaks and carbon dioxide retention measured upon expiration. A quasi-experimental pilot study was designed with eight volunteers in two experiments to determine the degree of leaks from the device, according to the observation of water vapor particle diffusion, on the one hand, and of thermal images on the other. The results from this study showed that the mask from the DORPEEP^© device at is tightest fit provided an adequate seal, although not fully airtight. In the thermal images and in the experiment with water vapor in our study, dispersions were mainly observed in the lower area in individuals with a beard. The DORPEEP^© device was shown to have only slight leaks.

Prehospital characteristics of COVID-19 patients transported by emergency medical service and the predictors of a prehospital sudden deterioration in Addis Ababa, Ethiopia

Background

Severally ill COVID-19 patients may require urgent transport to a specialized facility for advanced care. Prehospital transport is inherently risky; the patient’s health may deteriorate, and potentially fatal situations may arise. Hence, early detection of clinically worsening patients in a prehospital setting may enable selecting the best receiving facility, arranging for swift transportation, and providing the most accurate and timely therapies. The incidence and predictors of abrupt prehospital clinical deterioration among critically ill patients in Ethiopia are relatively limited.

Study objectives

This study was conducted to determine the incidence of sudden clinical deterioration during prehospital transportation and its predictors.

Methods

A prospective cohort study of 591 COVID-19 patients transported by a public EMS in Addis Ababa. For data entry, Epi data V4.2 and SPSS V 25 were used for analysis. To control the effect of confounders, the candidate variables for multivariable analysis were chosen using a p 0.25 inclusion threshold from the bivariate analysis. A statistically significant association was declared at adjusted relative risk (ARR) ≠ 1 with a 95 % confidence interval (CI) and a p value < 0.05 after adjusting for potential confounders.

Results

The incidence of prehospital sudden clinical deterioration in this study was 10.8%. The independent predictors of prehospital sudden clinical deterioration were total prehospital time [ARR 1.03 (95%; CI 1.00–1.06)], queuing delays [ARR 1.03 (95%; CI 1.00–1.06)], initial prehospital respiratory rate [ARR 1.07 (95% CI 1.01–1.13)], and diabetic mellitus [ARR 1.06 (95%; CI 1.01–1.11)].

Conclusion

In the current study, one in every ten COVID-19 patients experienced a clinical deterioration while an EMS provider was present. The factors that determined rapid deterioration were total prehospital time, queueing delays, the initial respiratory rate, and diabetes mellitus. Queueing delays should be managed in order to find a way to decrease overall prehospital time. According to this finding, more research on prehospital intervention and indicators of prehospital clinical deterioration in Ethiopia is warranted.

Inhaled nitric oxide as temporary respiratory stabilization in patients with COVID-19 related respiratory failure (INOCOV): Study protocol for a randomized controlled trial

Background

In March 2020, WHO announced the COVID-19 a pandemic and a major global public health emergency. Mortality from COVID-19 is rapidly increasing globally, with acute respiratory failure as the predominant cause of death. Many patients experience severe hypoxia and life-threatening respiratory failure often requiring mechanical ventilation. To increase safety margins during emergency anaesthesia and rapid sequence intubation (RSI), patients are preoxygenated with a closed facemask with high-flow oxygen and positive end-expiratory pressure (PEEP). Due to the high shunt fraction of deoxygenated blood through the lungs frequently described in COVID-19 however, these measures may be insufficient to avoid harmful hypoxemia. Preoxygenation with inhaled nitric oxide (iNO) potentially reduces the shunt fraction and may thus allow for the necessary margins of safety during RSI.

Methods and design

The INOCOV protocol describes a phase II pharmacological trial of inhaled nitric oxide (iNO) as an adjunct to standard of care with medical oxygen in initial airway and ventilation management of patients with known or suspected COVID-19 in acute respiratory failure. The trial is parallel two-arm, randomized, controlled, blinded trial. The primary outcome measure is the change in oxygen saturation (SpO₂), and the null hypothesis is that there is no difference in the change in SpO₂ following initiation of iNO.

Trial registration

EudraCT number 2020-001656-18; WHO UTN: U1111-1250-1698.

Protocol version: 2.0 (June 25^th, 2021).

Association between Prehospital Hypoxemia and Admission to Intensive Care Unit during the COVID-19 Pandemic: A Retrospective Cohort Study

Background and Objectives: The aim of this study was to assess the association between prehospital peripheral oxygen saturation (SpO₂) and intensive care unit (ICU) admission in confirmed or suspected coronavirus disease 19 (COVID-19) patients. Materials and Methods: We carried out a retrospective cohort study on patients requiring prehospital intervention between 11 March 2020 and 4 May 2020. All adult patients in whom a diagnosis of COVID-19 pneumonia was suspected by the prehospital physician were included. Patients who presented a prehospital confounding respiratory diagnosis and those who were not eligible for ICU admission were excluded. The main exposure was “Low SpO₂” defined as a value < 90%. The primary outcome was 48-h ICU admission. Secondary outcomes were 48-h mortality and 30-day mortality. We analyzed the association between low SpO₂ and ICU admission or mortality with univariable and multivariable regression models. Results: A total of 145 patients were included. A total of 41 (28.3%) patients had a low prehospital SpO₂ and 21 (14.5%) patients were admitted to the ICU during the first 48 h. Low SpO₂ was associated with an increase in ICU admission (OR = 3.4, 95% CI = 1.2–10.0), which remained significant after adjusting for sex and age (aOR = 5.2, 95% CI = 1.8–15.4). Mortality was higher in low SpO₂ patients at 48 h (OR = 7.1 95% CI 1.3–38.3) and at 30 days (OR = 3.9, 95% CI 1.4–10.7). Conclusions: In our physician-staffed prehospital system, first low prehospital SpO₂ values were associated with a higher risk of ICU admission during the COVID-19 pandemic.

High-flow nasal cannula therapy, factors affecting effective inspired oxygen fraction: an experimental adult bench model

Oxygenation through High Flow Delivery Systems (HFO) is described as capable of delivering accurate F_iO2. Meanwhile, peak inspiratory flow \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I ) of patients with acute hypoxemic respiratory failure can reach up to 120 L/min, largely exceeding HFO flow. Currently, very few data on the reliability of HFO devices at these high \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I are available. We sought to evaluate factors affecting oxygenation while using HFO systems at high \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I in a bench study. Spontaneous breathing was generated with a mechanical test lung connected to a mechanical ventilator Servo-i®, set to volume control mode. Gas flow from a HFO device was delivered to the test lung. The influence on effective inspired oxygen fraction of three parameters (F_iO2 0.6, 0.8, and 1, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I from 28 to 98.1 L/min, and HFO Gas Flows from 40 to 60 L/min) were analyzed and are reported. The present bench study demonstrates that during HFO treatment, measured F_iO2 in the lung does not equal set F_iO2 on the device. The substance of this variation (ΔF_iO2) is tightly correlated to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I (Pearson’s coefficient of 0.94, p-value < 0.001). Additionally, set F_iO2 and Flow at HFO device appear to significatively affect ΔF_iO2 as well (p-values < 0.001, adjusted to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I ). The result of multivariate linear regression indicates predictors (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I , Flow and set F_iO2) to explain 92% of the variance of delta F_iO2 through K-Fold Cross Validation. Moreover, adjunction of a dead space in the breathing circuit significantly decreased ΔF_iO2 (p < 0.01). The present bench study did expose a weakness of HFO devices in reliability of delivering accurate F_IO2 at high \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I as well as, to a lesser extent, at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}_{{\text{I}}}$$\end{document}V˙I below equivalent set HFO Flows. Moreover, set HFO flow and set F_IO2 did influence the variability of effective inspired oxygen fraction. The adjunction of a dead space in the experimental set-up significantly amended this variability and should thus be further studied in order to improve success rate of HFO therapy.

A retrospective survey study of paramedic students' exposure to SARS-CoV-2, participation in the COVID-19 pandemic response, and health-related quality of life

Background

Healthcare workers have reported increased anxiety while working in hospitals during the COVID-19 pandemic, and the role of healthcare students in a health crisis has been discussed among clinicians and researchers. The simultaneous international shortage of personal protection equipment (PPE) during the first wave of the pandemic potentially exposed healthcare workers and students to the virus during their work and clinical training. Our aim was therefore to evaluate the extent to which paramedic students in Oslo, Norway, were exposed to the SARS-CoV-2 virus and were involved in voluntary and/or paid healthcare-related work. An evaluation was also made of the students’ COVID-19-related symptoms and of their health-related quality of life (HRQoL) during the first wave of the pandemic.

Methods

Paramedic students (n = 155) at Oslo Metropolitan University, Norway, were invited to complete an online survey five months after the first cases of COVID-19 were detected. The university was situated in the epicenter of the pandemic in Norway. The responses were analyzed using descriptive statistics, independent sample t-tests, and linear regression analysis.

Results

Of the 109 respondents (70.3%), 40 worked in patient-related healthcare work. Of those, seven (17.5%) students experienced insufficient supplies of PPE, six (15.0%) participated in aerosol-generating procedures without adequate PPE, and nine (22.5%) experienced insufficient time to don PPE. Seventy-five (70.1%) students experienced no COVID-19-related symptoms, and no students tested positive for COVID-19. HRQoL was scored 0.92 (sd 0.12), which was significantly higher than for the general population before the pandemic (p = 0.002). Students continued with their education and participated in a variety of pandemic-related emergency tasks during the first wave of the pandemic.

Conclusions

Paramedic students were valuable contributors to the national pandemic response. Despite potential exposure to SARS-CoV-2 in unpredictable emergency settings with limited supplies of personal protection equipment, no students tested positive for COVID-19. Their health-related quality of life remained high. Students’ participation and utilization in similar health crises should be considered in future health crises.