A randomized trial on subject tolerance and the adverse effects associated with higher- versus lower-flow oxygen through a standard nasal cannula.

STUDY OBJECTIVE: Experts advocate the use of a standard nasal cannula to provide oxygen at flow rates of up to 15 L/minute during emergency intubation. However, because of concerns about potential patient discomfort, some providers avoid providing nasal cannula oxygen at flow rates greater than 6 L/minute. This trial is designed to determine the participants' ability to tolerate 10 minutes of nasal cannula oxygen at higher flow rates. METHODS: This was a prospective, randomized, crossover trial of healthy volunteers at an emergency department in New Zealand. Participants were randomized to first receive either higher-flow (15 L/minute) or lower-flow (6 L/minute) nasal cannula oxygen for 10 minutes. After a 1-hour washout period, they received the alternate flow rate for 10 minutes. The primary outcome was the ability to tolerate 10 minutes of the nasal cannula oxygen at each flow rate. The secondary outcome was the difference in discomfort between the flow rates as measured on a 100-mm visual analog scale. RESULTS: All 77 of the participants (100%) were able to tolerate 10 minutes at both flow rates. Participants rated the higher-flow nasal cannula oxygen as a mean of 25 mm (SD 20 mm) more uncomfortable than the lower-flow nasal cannula oxygen. One minute after the oxygen was discontinued, the mean difference in discomfort between the flow rates was a clinically insignificant 9.8 mm (SD 17 mm) more uncomfortable. There were no adverse events. CONCLUSION: Participants were able to tolerate higher-flow nasal cannula oxygen for 10 minutes without difficulty. Higher-flow nasal cannula oxygen at 15 L/minute was associated with some discomfort, but the discomfort quickly dissipated and caused no adverse events.

Prevention and treatment of motion sickness.

Motion sickness is a common syndrome that occurs upon exposure to certain types of motion. It is thought to be caused by conflict between the vestibular, visual, and other proprioceptive systems. Although nausea is the hallmark symptom, it is often preceded by stomach awareness, malaise, drowsiness, and irritability. Early self-diagnosis should be emphasized, and patients should be counseled about behavioral and pharmacologic strategies to prevent motion sickness before traveling. Patients should learn to identify situations that will lead to motion sickness and minimize the amount of unpleasant motion they are exposed to by avoiding difficult conditions while traveling or by positioning themselves in the most stable part of the vehicle. Slow, intermittent exposure to the motion can reduce symptoms. Other behavioral strategies include watching the true visual horizon, steering the vehicle, tilting their head into turns, or lying down with their eyes closed. Patients should also attempt to reduce other sources of physical, mental, and emotional discomfort. Scopolamine is a first-line medication for prevention of motion sickness and should be administered transdermally several hours before the anticipated motion exposure. First-generation antihistamines, although sedating, are also effective. Nonsedating antihistamines, ondansetron, and ginger root are not effective in the prevention and treatment of motion sickness.

Presenting characteristics, length of stay and oxygen use among COVID-19 cases at a single tertiary hospital in Auckland, New Zealand, using retrospective medical recorded data.

AIMS: The purpose of our current study was to analyse demographic and presenting characteristics of COVID-19 patients, including assigning clinical severity scores, and analyse with respect to oxygen utilisation and hospital course. METHODS: This was a retrospective observational study of COVID-positive patients presenting to the Emergency Department at Middlemore Hospital in Auckland, New Zealand. Data were collected between 1 August 2021 and 1 November 2021. They were followed through 20 December 2021. Data were obtained from both the EMR system and paper charts for all eligible patients during the study period. RESULTS: There were 171 patients included, with 187 patient presentations. Oxygen data were collected on 123 admitted patients and showed that 47% of admission time was spent off oxygen. Of the total presentations, the median length of stay (LOS) was 4 days. The severity of presenting illness was associated with disposition and predictive of LOS. CONCLUSIONS: Approximately half of the admitted patient's hospital time involved no oxygen use, which suggests that we may be able to further risk stratify in order to decrease the number and duration of hospital admissions going forward. As expected, clinical severity scores were associated with oxygen utilisation, disposition and LOS.

Environmental monitoring tools and strategies in salmon net-pen aquaculture.

As global salmon production accelerates in response to higher consumer demand for seafood, so does the need for sophisticated monitoring strategies to enable and maintain ethically sound, productive, and environmentally friendly production of fish. Innovative technologies are needed to ensure proper water quality, react to unfavorable hydrodynamic conditions, monitor for changes in fish health, and minimize ecological interactions with indigenous aquatic life, including fish escapes. Automated sensors connected wirelessly to data stations, visualization aids, and acoustic and physical tagging technologies are emerging tools capable of detecting environmental stress and its associated behavioral changes in farmed fish. Computer modeling of the monitoring data collected from a single salmon farm or collection of farms sharing a data network can be used to spot environmental trends vital for anticipating some of the consequences of climate change. Environmental regulations governing salmon farming in coastal areas are becoming more stringent in response to public pressures to protect coastal and ocean resources and to provide for multipurpose use of marine resources. As net-pen salmon aquaculture expands globally, new technologies will be essential to collect and interpret the anticipated larger volumes of data needed to meet these stringent regulatory requirements and to safeguard the high investment costs inherent in salmon farming. Integr Environ Assess Manag 2022;18:950-963. © SETAC.

Strategies to work towards long-term sustainability and resiliency of nature-based solutions in coastal environments: A review and case studies.

The need for sustainable and resilient long-term strategies for coastal restoration and development projects is largely the result of pressures brought by changing climate conditions and growing human populations along coastal boundaries. As anthropogenic impacts along our coasts increase, the demand for sustainable, nature-based solutions (NbS) will grow commensurately. Trusted approaches are needed for successful implementation of NbS, especially in regions hardest hit by environmental changes. Nearshore strategies for new construction and protection of existing coastal infrastructure are shifting rapidly from hardened approaches to more ecologically aligned techniques that work with natural forces and enhance natural habitat. This paper highlights the benefits of living shorelines composed of ecotypic native plants, wave attenuation structures for coastal protection, and managed retreat to restore coastal environments while supporting and maintaining natural habitats. We review several NbS and present two case studies to illustrate the value of incorporating nature-based approaches to vulnerable coastal environments and highlight the importance of maximizing synergies and understanding trade-offs in their long-term use. Integr Environ Assess Manag 2022;18:123-134. © 2021 SETAC.

A comparison of bacterial colony-forming units in water bottles and hydration bags among outdoor enthusiasts.

OBJECTIVE: Transporting clean drinking water in an easily accessible container is a priority for many outdoor enthusiasts. Two basic hydration systems are commonly used to provide water: the water bottle and the hydration bladder. The authors tested the hypothesis that there were different levels of microbiologic contamination between these 2 systems. METHODS: Sixty-seven water samples were collected using sterile techniques from outdoor enthusiasts at several outdoor recreational locations. These users were then asked to complete a brief survey that reported demographic information and details of water container use. Water samples were then plated on sheep blood agar, and the colony-forming units were counted after 24 hours of growth. The 2 groups were compared using Student's t test. RESULTS: The 2 groups using water bottles or hydration bladders did not show significant differences in container age, duration of outdoor activity, or duration since last cleaning. The groups differed slightly in their composition of hikers/walkers/runners vs cyclists. The water bottle group had a mean colony-forming unit count per 100 mL of 37 (95% CI 26-48), and the hydration bladder had a mean of 27 (95% CI 17-35). CONCLUSIONS: There was no statistically significant difference between hydration bladders and water bottles in microbial contamination or colonization. Judging from the available data, outdoor enthusiasts should select their water container based on criteria other than the relative exposure to microbes. Additional study is required to replicate this finding in other locations and with improved sample methodology.

Hemostatic containment - an evolutionary hypothesis of injury by innate immune cells.

Tissue damage mediated by innate immune cells in reperfusion injury may have a survival benefit in infections, preventing sepsis. Tissue damage by leukocytes - plugging of small vessels, endothelial cell damage, tissue edema around vessels, and stimulation of platelet aggregation - occurs in both reperfusion injury and infection-prone wounds. These events create a physical barrier that may sequester bacteria, preventing bacterial invasion of the blood. This antisepsis effect, termed "hemostatic containment," is triggered by signals that convey susceptibility to infection, such as poor blood flow and oxygenation. In active and incipient infections, the host accepts some sacrifice of body tissues while preventing pathogens from gaining access into sterile sites. This tradeoff prevents bacteremia and promotes survival in diseases such as abscesses. Other diseases mimic infection-prone states and elicit costly host injury that exceeds antibacterial benefits. Mimic diseases include cocaine-induced heart attacks and decompression illness. Mimics produce signals that active innate immune cells despite the absence of pathogens. Atherosclerotic cardiovascular diseases comprise an intermediate, or pseudo-mimic, state characterized by indolent pathogens that rarely cause sepsis. Treatment of innate immune cell injury is likely to be more effective for mimic and pseudo-mimic states than for infectious diseases. Interventions against reperfusion injury might be most effective when they improve host immune defenses while eliminating signals of infection risk.

Viewpoint: learning professionalism: a view from the trenches.

The authors, medical students immersed in learning professionalism, observe that most of the professionalism literature misses the mark. Their views on professionalism education, although not the result of qualitative research, were gained from four years of conversations with students from a dozen medical schools, plus online student discussions, focus groups, and meetings with supervisors from five schools. The authors propose that the chief barrier to medical professionalism education is unprofessional conduct by medical educators, which is protected by an established hierarchy of academic authority. Students feel no such protection, and the current structure of professionalism education and evaluation does more to harm students' virtue, confidence, and ethics than is generally acknowledged. The authors maintain that deficiencies in the learning environment, combined with the subjective nature of professionalism evaluation, can leave students feeling persecuted, unfairly judged, and genuinely and tragically confused. They recommend that administrators, medical educators, residents, and students alike must show a personal commitment to the explicit professionalism curriculum and address the hidden curriculum openly and proactively. Educators must assure transparency in the academic process, treat students respectfully, and demonstrate their own professional and ethical behavior. Students overwhelmingly desire to become professional, proficient, and caring physicians. They seek professional instruction, good role models, and fair evaluation. Students struggle profoundly to understand the disconnect between the explicit professional values they are taught and the implicit values of the hidden curriculum. Evaluation of professionalism, when practiced in an often unprofessional learning environment, invites conflict and compromise by students that would otherwise tend naturally toward avowed professional virtues.

Lessons learned from a study-group pilot program for medical students perceived to be 'at risk'.

BACKGROUND: At the University of New Mexico School of Medicine (UNM-SOM) we have noticed that some first year medical students have difficulty accurately assessing their academic skills and are often afraid to seek help. This leads to marginal performance and sometimes even failure. Therefore, we developed a preemptive intervention using peer-led study groups based on the personalized System of Instruction (PSI). AIM: The goal of this pilot study was to evaluate this approach for assisting students, interms of student success, and cast benefit. METHODS: Thirteen first-year medical students considered to be 'at risk' of academic difficulty took part in a six-month pilot intervention. They participated in structured study groups that were facilitated by upper-level medical students. The groups met twice weekly for up to two hours each time. The at-risk students took short multiple-choice quizzes and discussed major concepts. If students did not achieve 80% or better on the quizzes, they were required to take a second quiz to demonstrate mastery. Summative exam scores from four groups of students were compared: those with Medical College Admission Test (MCAT) scores <25, who received the study group intervention; their classmates with MCAT scores >25 who did not receive the intervention; and two matched groups from the previous year, none of whom had access to the structured study groups. RESULTS: No significant differences in exam scores were seen between the group who received the intervention and the matched group who did not. CONCLUSIONS: Despite this result, we learned several useful lessons about study groups and interactions between first-year and upper-level medical students: (1) Students perceived participation in the study groups as a good learning strategy, but preferred participation not be mandated. It may be preferable to train and encourage students to run their own study groups. (2) Both students and proctors acknowledged interpersonal benefits from the program but, as these benefits can be achieved by other means, an expensive proctor-based program is not, we believe, the best use of academic support resources. (3) Focus in the study groups was on content for the quizzes, but more attention to how-to-learn strategies may have had greater impact.

Systematic review and meta-analysis of first-pass success rates in emergency department intubation: Creating a benchmark for emergency airway care.

OBJECTIVE: Many EDs have begun to evaluate their airway performance. The first-pass success (FPS) rate is a commonly used marker of proficiency, and has been associated with rates of adverse events. The aim of this systematic review and meta-analysis is to quantify the ED FPS rates and summarise the rates of adverse events associated with endotracheal intubation. METHODS: A structured literature search was performed through MEDLINE and EMBASE. Research published since 2000 was included if it prospectively collected data on all patients intubated in the ED and reported the FPS rates. Data on demographics, indication, FPS rates, adverse events, proportion by RSI and proportion by emergency medicine doctors were extracted. Pooled mean FPS rates were estimated using a random effects model. RESULTS: The literature search generated 21 162 articles. Full-text review identified 16 publications for meta-analysis. This included a total of 42 081 intubations from 83 institutions, in 10 countries. The FPS rate was 84.1% (95% confidence interval [CI] 80.1-87.4] in the 'ED-All' group and 81.8% (95% CI 76.3-86.2) in the 'Trauma-Only' group. The incidence rates of commonly reported adverse events were hypoxia 6.4% (95% CI 2.5-11.9), hypotension 3.0% (95% CI 1.5-4.9), oesophageal intubation 3.5% (95% CI 2.3-4.9), greater than three attempts 0.8% (95% CI 0.4-1.4), cricothyrotomy 0.3% (95% CI 0.1-0.5) and peri-intubation cardiac arrest 0.6% (95% CI 0.2-1.0). CONCLUSION: Research published in the last 16 years shows a mean ED FPS rate of 84.1%. This represents the best available published data that can be used to benchmark emergency airway performance.

Comparison of four methods of endotracheal tube passage in simulated airways: There is room for improved techniques.

OBJECTIVE: Endotracheal intubation requires laryngoscopy followed by passage of the endotracheal tube (ETT). Tube passage can be difficult, but there is little evidence to support which adjunct for tube passage is most effective. METHODS: The four tube passage adjuncts tested were the naked ETT, stylet ETT, railroaded bougie and preloaded bougie. Participants completed pre- and post-test surveys identifying demographics, experience and method preference. After instruction, participants completed eight intubations on manikins with 'easy' and 'difficult' airways. RESULTS: One hundred and seventeen practitioners who were experienced emergency medicine physicians, anaesthesiologists and out-of-hospital providers completed 936 total ETT attempts. For the 'difficult' airway, the percentage first pass success (95% confidence interval [CI]) for the naked ETT was 30.8% (23.1-39.7%). This was significantly lower than the stylet ETT (95.7% [86.6-100%]), the railroaded bougie (75.2% [63.8-86.6%]), or the preloaded bougie (89.7% [79.7-99.7%]). On difficult airways, the median (interquartile range [IQR]) time-to-intubation was fastest in the stylet ETT (25.0 s [20.9-32.2 s]) with the railroaded bougie being the slowest (43.2 s [36.5-56.2 s]). Seventy-nine per cent of participants stated that they would change their practice based on participating in this study. Participants increased their preference for the preloaded bougie from 30.6% to 69.4%. CONCLUSION: The data show that tube passage with a stylet ETT or a preloaded bougie is superior in terms of higher first pass success, faster time-to-intubation and higher post-test preference. The naked ETT is clearly inferior to other methods. This research supports the recommendation to use a stylet ETT or bougie for every predicted difficult intubation.

Acceptability of the flipped classroom approach for in-house teaching in emergency medicine.

OBJECTIVE: To evaluate the relative acceptability of the flipped classroom approach compared with traditional didactics for in-house teaching in emergency medicine. METHODS: Our department changed its learning model from a 'standard' lecture-based model to a 'flipped classroom' model. The 'flipped classroom' included provided pre-session learning objectives and resources before each 2 h weekly session. In-session activities emphasised active learning strategies and knowledge application. Feedback was sought from all medical staff regarding the acceptability of the new approach using an online anonymous cross-sectional qualitative survey. RESULTS: Feedback was received from 49/57 (86%) medical staff. Ninety-eight per cent (48/49) of respondents preferred the flipped classroom over the traditional approach. Aspects of the flipped classroom learners liked most included case-based discussion, interaction with peers, application of knowledge, self-directed learning and small-group learning. Barriers to pre-session learning include work commitments, 'life', perceived lack of time, family commitments, exam preparation and high volume of learning materials. Reported motivational factors promoting pre-session learning include formal assessment, participation requirements, more time, less material, more clinical relevance and/or more interesting material. Case studies and 'hands-on' activities were perceived to be the most useful in-session activities. CONCLUSION: The flipped classroom shows promise as an acceptable approach to in-house emergency medicine teaching.

Physician attitudes about prehospital 12-lead ECGs in chest pain patients.

INTRODUCTION: The prehospital 12-lead electrocardiogram (ECG) has become a standard of care. For the prehospital 12-lead ECG to be useful clinically, however, cardiologists and emergency physicians (EP) must view the test as useful. This study measured physician attitudes about the prehospital 12-lead ECG. HYPOTHESIS: This study tested the hypothesis that physicians had "no opinion" regarding the prehospital 12-lead ECG. METHODS: An anonymous survey was conducted to measure EP and cardiologist attitudes toward prehospital 12-lead ECGs. Hypothesis tests against "no opinion" (VAS = 50 mm) were made with 95% confidence intervals (CIs), and intergroup comparisons were made with the Student's t-test. RESULTS: Seventy-one of 87 (81.6%) surveys were returned. Twenty-five (67.6%) cardiologists responded and 45 (90%) EPs responded. Both groups of physicians viewed prehospital 12-lead ECGs as beneficial (mean = 69 mm; 95% CI = 65-74 mm). All physicians perceived that ECGs positively influence preparation of staff (mean = 63 mm; 95% CI = 60-72 mm) and that ECGs transmitted to hospitals would be beneficial (mean = 66 mm; 95% CI = 60-72 mm). Cardiologists had more favorable opinions than did EPs. The ability of paramedics to interpret ECGs was not seen as important (mean = 50 mm; 95% CI = 43-56 mm). The justifiable increase in field time was perceived to be 3.2 minutes (95% CI = 2.7-3.8 minutes), with 23 (32.8%) preferring that it be done on scene, 46 (65.7%) during transport, and one (1.4%) not at all. CONCLUSIONS: Prehospital 12-lead ECGs generally are perceived as worthwhile by cardiologists and EPs. Cardiologists have a higher opinion of the value and utility of field ECGs. Since the reduction in mortality from the 12-lead ECG is small, it is likely that positive physician attitudes are attributable to other factors.

Gene-environment mismatch in decompression sickness and air embolism.

Decompression sickness causes injury and death in SCUBA divers when air bubbles obstruct the flow of blood. Platelets aggregate in response to gas and promote inflammation. Inflammation in decompression sickness may have its origin in the innate immune system's response to pathogens. Bubbles are often found in tissues during gas-forming infections and in infection-prone states. In these diseases, intravascular gas offers a signal of infection to immune cells. Platelet activation by gas may often accompany a beneficial immune response to pathogens. Pathologic bubble-platelet interaction in decompression illness may be an example of gene-environment mismatch.

The prehospital 12-lead electrocardiogram's effect on time to initiation of reperfusion therapy: a systematic review and meta-analysis of existing literature.

The prehospital electrocardiogram (ECG) is becoming the standard of care of suspected cardiac chest pain. We evaluated the evidence regarding the prehospital ECG and sought to quantify the reduction in time to reperfusion therapy attributable to the prehospital ECG. We conducted a systematic review and analyzed studies that were conducted in emergency medical systems relevant to providers in the United States. The papers were limited to studies that reported original data that compared prehospital ECG to no prehospital ECG groups. Four studies containing 99 patients met the inclusion criteria. A meta-analysis of these studies revealed a difference of 24.7 (95% confidence interval, 16.7-32.7) minutes. Providers now have a quantified value of the prehospital ECG based on the best published evidence. In addition, this search showed a relatively low quality and quantity of research on the prehospital ECG.