In this episode, hosts Iain Beardsell and Simon Carley provide the St Emlyn's podcast blog update for July 2024. They discuss their recent experiences, including Simon's trip to Malaysia for the MRCEM exams and Iain's upcoming attendance at the Tactical Trauma conference in Sweden.

The main topics include a systematic review on the Manchester Acute Coronary Score (MACS) and its application in emergency departments, the potential influence of AI in diagnosing occlusive myocardial infarctions through ECGs, and guidelines for managing non-fatal strangulation cases. Additionally, they touch on the feasibility of using lidocaine patches for elderly patients with rib fractures and the role of partial REBOA in pre-hospital care for exsanguinating subdiaphragmatic haemorrhage.

They also highlight informative segments from the premier conference on pediatric emergency medicine, covering topics such as eating disorders, hybrid closed-loop insulin pumps, and button battery ingestion. Finally, they emphasize the importance of understanding medical statistics and using diagnostic tests effectively in emergency medicine practice.

00:00 Introduction and Summer Updates

00:55 Upcoming Conferences and Events

01:44 Manchester Acute Coronary Score (MACS) Review

05:30 AI in ECG Analysis with Steve Smith

08:18 Non-Fatal Strangulation Awareness

10:45 Reboa: Pre-Hospital Use and Insights

14:11 Pediatric Emergency Medicine Highlights

14:36 Eating Disorders and Diabetes Management

19:00 Lidocaine Patches for Rib Fractures

21:46 Critical Appraisal and Medical Statistics

24:28 Button Battery Ingestion Dangers

26:12 Conclusion and Farewell

Our monthly podcast round up from St Emlyn's Blog. This month Simon and Iain discuss the prehospital use of troponin measurement in the assessment of patients with chest pain and the use of AI in medicine, as well as an update about St Emlyn's WILD.

Please do like and subscribe

The latest CAN is one of our brand-new 'revision editions' -- brief podcasts aimed at covering the essentials of critical appraisal for medical students and junior doctors preparing for exams.

With the help of Gregory Yates, an academic doctor based in Manchester, this episode introduces two core concepts: sensitivity and specificity. These are two ways of thinking about the accuracy of a diagnostic test. Knowing the sensitivity and specificity of an investigation will give you a decent idea of how it should be used in the emergency department.

Sensitivity (Sn) describes the chance that a test will be positive if your patient has the condition you're testing for. Some people call it the 'true positive rate' or alternatively the positivity in disease (PID) rate. If you need a hand remembering it, you can always remember that PID is a sensitive issue.

Meanwhile, specificity (Sp) considers the chance of a test being negative if the patient doesn't have the condition you're testing for. It's the 'true negative rate' or alternatively the negativity in health (NIH) rate. There are times when we particularly need a test to have a high sensitivity. This is generally when we want to be particularly confident that a test accurately identifies everyone with the relevant condition because we really don't want to miss it. We need a high sensitivity to rule out disease. (Sn-uff it out). At other times, we need to be confident that a patient with a positive test actually has the disease - for example, if the treatment is unpleasant or involves exposing patients to risk. In that case, we want a high specificity to rule in disease. (Sp-in it in).

In this CAN, we use D-Dimer as an example of a very sensitive investigation: it’s positive in nearly 100% of cases of venous thromboembolism. Specificity describes the likelihood that the test will be negative if your patient does not have the disease. We use HbA1c as an example of a highly specific investigation: it’s rarely used in the emergency department, but if it’s elevated, we can be almost certain that the patient is diabetic. HbA1c is almost never (<1%) raised in non-diabetics.

The trouble is, many patients with a positive D-Dimer do not have a venous clot, and the majority of diabetics will have a normal HbA1c! No test is perfect, and we discuss how emergency physicians weigh up sensitivity and specificity when choosing which investigations are the best "fit" for clinical decision-making. By the end of this CAN, you will be ready to do the same -- in your exams, and on the shop floor.

In our new regular slot of the middle Monday of the month we're delighted to bring you the highlights from the St Emlyn's blog this month.,

Iain and Simon chat about batching in EDs, Ossilation in decision making and a whole lot more about trauma (chest drains, extrication, sex and TXA and rib fixation).

Please do like and subscribe and keep an eye out for our new sister website St Emlyn's Medical School and it's podcast series coming soon. 

Our monthly round up of all from the St Emlyn's blog. We discuss pathways into emergency care research, pad positioning in cardioversion of AF and possible gender differences in the presciption of TXA in trauma.

We also chat about travel in Lithuania, memories of defibrillating with hand held paddles and Simon's recent forst infection with COVID.

We mention a post on Lyme disease which you can read here (especially if you live near the New Forest...)

Prof. Rick Body is an internationally recognised expert in diagnostic testing. In this podcast he takes us through diagnostics today and also the near future which may change almost everything. 

You can read more and see the slides/video at http://www.stemlynsblog.com

St. Emlyn's April 2019 Podcast Highlights

Hello and welcome to the St. Emlyn's blog. I'm Simon Carley, and today I'll be sharing the exciting developments from April 2019 on our St. Emlyn's blog. This month has been packed with insightful posts and groundbreaking research, so let's dive in.

Andromeda Shock Trial: A New Perspective

We begin with a thought-provoking journal club post by Dan Horner, an intensivist and emergency physician, who explores the Andromeda Shock trial. This study, conducted in Argentina, compared two resuscitation strategies for patients with septic shock: targeting lactate levels versus peripheral perfusion as measured by capillary refill time.

The Andromeda Shock trial is fascinating because it challenges our reliance on measurable indicators like lactate levels. Many experts argue that lactate doesn't provide the information we think it does about sepsis. Rich Carden's excellent blog on lactate delves into this topic, explaining why the common assumption that lactate indicates anaerobic metabolism is incorrect. Insights from leading intensivists like John Mayberg and Simon Finfer prompt a reevaluation of how we interpret lactate levels.

In the trial, patients managed using peripheral perfusion monitoring showed better outcomes than those managed by lactate levels. Although the trial is underpowered to show definitive differences, the findings suggest that both methods are likely similar in effectiveness. This study highlights the need to reconsider our approach to monitoring septic shock patients and suggests that capillary refill time could be a valuable, low-cost alternative to lactate measurement.

Enhancing Learning with Minimal Effort

Next, we turn to an intriguing blog by Nick Smith, who shares a lazy yet effective way to enhance learning. Inspired by Matthew Walker's book "Why We Sleep," Nick discusses the critical role of rest in learning and retention. The key takeaway is simple: if you're not well-rested before and after learning, you won't retain information effectively.

Nick emphasizes understanding individual learning rhythms. Some people, like early risers, learn best in the morning, while night owls perform better later in the day. This insight is crucial for medical educators and learners alike. For instance, teenagers naturally have later sleep cycles, making early morning learning sessions less effective.

Walker’s book provides compelling evidence on how sleep affects cognitive function and memory consolidation. During sleep, particularly REM sleep, the brain processes and organizes information learned throughout the day. Lack of sleep disrupts this process, leading to poorer retention and understanding.

Nick integrates these scientific insights with practical advice, making his blog an invaluable resource for optimizing learning strategies. He offers tips on improving sleep hygiene, such as maintaining a consistent sleep schedule, creating a restful environment, and avoiding stimulants before bedtime.

Nick also highlights the impact of disrupted sleep patterns, especially when attending international conferences. Jet lag and lack of sleep can severely hamper your ability to absorb new information. Moreover, alcohol consumption negatively affects learning, which is worth considering during conference social events.

Nick's post is packed with practical tips and impressive infographics that make the information easily digestible. It's a must-read for anyone involved in medical education or looking to optimize their learning strategies.

Aortic Emergencies: Key Insights from George Willis

George Willis, a renowned speaker and former professional American football player, presented on aortic emergencies at the St. Emlyn's Live Conference. His talk is a goldmine of information for emergency medicine practitioners. Aortic emergencies, such as ruptured aortic aneurysms and dissections, are critical conditions that require swift diagnosis and management.

George emphasizes using clinical history and tools like ultrasound to diagnose aortic emergencies. For example, ultrasound can identify abdominal aortic aneurysms and dissections via transthoracic echo. He also discusses managing these patients, particularly those with dissections, who present unique challenges due to their unstable blood pressure.

One notable case George describes involves managing pericardial effusion and tamponade resulting from aortic dissection. Techniques like pericardiocentesis can be life-saving, buying valuable time for definitive treatment. George's practical tips and real-world examples make his presentation an invaluable resource for anyone dealing with aortic emergencies.

Managing aortic emergencies requires a nuanced approach, particularly when dealing with unstable patients. George discusses using medications like labetalol for beta-blockade and alpha-blockade to manage blood pressure in dissection patients. These medications help reduce the strain on the aorta without compromising patient safety.

George also covers using imaging techniques, such as CT angiography, to confirm diagnoses and plan interventions. The ability to quickly and accurately diagnose these conditions is crucial for timely surgical intervention, which can significantly improve patient outcomes.

Ambulatory Care for PEs: Dan Horner's Expert Insights

Dan Horner returns with another insightful blog, this time on the ambulatory management of pulmonary embolisms (PEs). At the Arkham conference in Belfast, Dan discussed the benefits and challenges of treating PEs as outpatients. His post is a comprehensive guide to identifying which patients can be safely managed at home and which require hospital admission.

Dan explores various prognostic factors and scoring systems, such as PESI and sPESI, used to predict complications in PE patients. While these scores are better than Gestalt, they are not without limitations. Dan also touches on biomarkers and their role in predicting PE outcomes, though current data is not definitive.

Identifying patients who can be safely managed on an outpatient basis is crucial for optimizing resource use and improving patient comfort. Dan discusses the criteria for outpatient management, including the absence of hemodynamic instability, low bleeding risk, and adequate home support. These criteria help ensure that only patients with a low risk of complications are selected for ambulatory care.

Treatment options for PEs are evolving, with a shift from traditional anticoagulants like Warfarin to NOACs/DOACs. While these newer agents offer convenience, the evidence base is still developing. Dan also addresses the complexities of managing PEs in special populations, such as pregnant patients, highlighting the need for individualized care and informed discussions with patients.

Implementing ambulatory care for PEs requires careful planning and coordination. Dan provides practical advice on setting up ambulatory care pathways, including patient education, follow-up protocols, and the use of telemedicine to monitor patients remotely. He also discusses the importance of multidisciplinary collaboration in managing these patients.

Dan's blog is a treasure trove of resources, including guidelines for outpatient management, risk scores, and follow-up strategies. It's an essential read for anyone involved in the care of PE patients, offering the latest evidence and practical advice.

Coping with Clinical Tragedies: Liz Crowe's Personal Journey

To conclude our April roundup, we have two deeply moving blogs by Liz Crowe, where she shares her experiences of dealing with clinical tragedies. Liz's candid account of a recent tragic event in her professional life resonates with many healthcare professionals who have faced similar situations. Her blogs not only describe the emotional impact of these events but also offer strategies for coping and recovery.

Liz's first blog delves into the profound emotional toll that clinical tragedies can take on healthcare providers. She describes the initial shock, feelings of guilt and helplessness, and the long-lasting impact on mental health. These experiences are not uncommon in the medical field, where the stakes are high, and the outcomes can sometimes be devastating.

Liz emphasizes the importance of acknowledging and processing these experiences, rather than burying the emotions. She provides practical advice on how to support yourself, your colleagues, and your loved ones during such challenging times. Liz's insights are invaluable for anyone in the healthcare field, offering guidance on how to navigate the emotional aftermath of clinical tragedies.

In her second blog, Liz focuses on strategies for coping with and recovering from clinical tragedies. She highlights the importance of seeking professional help when needed, whether through counseling, peer support groups, or other mental health resources. Liz also emphasizes the value of self-care practices, such as exercise, mindfulness, and maintaining a healthy work-life balance.

Liz shares her personal journey of recovery, including the support she received from colleagues and the strategies that helped her regain her confidence and resilience. Her story is a powerful reminder that, while clinical tragedies are deeply challenging, it is possible to heal and continue to provide compassionate care to patients.

Liz's blogs also underscore the importance of building a supportive community within the healthcare profession. She advocates for open conversations about mental health and the emotional challenges of medical practice, fostering an environment where healthcare providers feel safe to share their experiences and seek help.

Liz's blogs are a must-read for anyone who has experienced or is supporting someone through a clinical tragedy. They offer hope and practical strategies for healing and moving forward.

Final Thoughts

April 2019 has been an incredibly insightful month on the St. Emlyn's blog. From groundbreaking research and practical medical education tips to deeply personal reflections on clinical tragedies, we've covered a wide range of topics. Each post offers valuable insights and practical advice for healthcare professionals.

As we continue to face the challenges of a busy emergency department, it's crucial to stay informed and up-to-date with the latest evidence and best practices. Whether you're managing septic shock, improving your learning strategies, diagnosing aortic emergencies, treating PEs, or coping with clinical tragedies, the St. Emlyn's blog has you covered.

The diversity of topics covered this month highlights the importance of continuous learning and adaptation in emergency medicine. By staying abreast of the latest research and best practices, we can ensure that we are providing the highest quality care to our patients.

Thank you for joining us on this journey through April 2019. We hope you find these posts as enlightening and helpful as we do. Stay tuned for more exciting updates and insights from the St. Emlyn's team. Enjoy your emergency medicine practice, and we'll speak to you again soon.

Highlights from March 2019: Key Insights and Updates

Welcome to the St Emlyn's podcast. I'm Simon Carley and today; I'll be taking you through the highlights from our blog in March 2019. This was a busy month filled with exceptional content, insightful trips, and significant conferences. Let's dive into the details and explore some key topics, starting with adult congenital heart disease, top trauma papers, and the importance of responsible volunteering.

Management of Adult Congenital Heart Disease

March kicked off with an important post on the management of adult congenital heart disease (ACHD). This topic is particularly close to my heart as the hospital I work at is a level two centre for ACHD in the UK. Services have become centralized, and surgical components are now managed at a few specialized centres, with Liverpool being the hub for my region.

Despite this centralization, we still encounter a large population of ACHD patients in our area. These patients often present complex medical histories and unique pathologies that can be challenging to manage in emergency settings. The guidance available typically focuses on chronic and surgical management, but emergency care for these patients requires a different approach.

Common Issues in ACHD Patients

ACHD patients commonly present with dysrhythmias, which can be particularly challenging to manage. Chest pain is also prevalent, although the incidence of ischemic heart disease isn’t significantly higher in ACHD patients, except for those who have undergone certain procedures like the switch operation. Other common issues include:

• Cyanotic patients: Those with single ventricle physiology and right-to-left shunts.
• Endocarditis: A rare but serious complication.
• Non-cardiac problems: Managing ACHD patients with conditions like appendicitis or pneumonia can be complex due to their unique circulatory dynamics.

The bottom line is that these patients often require specialized management strategies. When ACHD patients present with cardiac complications, we consult our local cardiologist or the ACHD centre. However, non-cardiac issues in ACHD patients also warrant discussion with the ACHD centre to ensure comprehensive care.

Key Takeaways for Emergency Physicians

Emergency physicians should familiarize themselves with the unique aspects of Fontan circulation, which relies on venous return based on venous pressure. Aggressive interventions like CPAP, bagging, and diuretics can be detrimental. Understanding these nuances is crucial for providing optimal care.

A Deeper Dive into Fontan Circulation

The Fontan procedure, a surgical intervention for single ventricle defects, creates a unique circulatory system that can be difficult to manage in emergency settings. Unlike normal circulation, Fontan physiology depends heavily on passive blood flow from the veins to the lungs. This means that increasing intrathoracic pressure through methods like CPAP or bagging can reduce cardiac output and worsen the patient's condition.

Fontan patients are particularly vulnerable to fluid shifts and pressures, making careful management of intravenous fluids and medications essential. Understanding these dynamics can be life-saving in the ED. For example, while diuretics might seem a reasonable choice for a patient with fluid overload, they can lead to dangerously low preload and cardiac output in a Fontan patient.

Top Trauma Papers from the Trauma UK Conference

Next up, we revisited some of the top trauma papers presented at the Trauma UK conference. These papers covered a range of topics, from the use of bougies in the ED to bag-mask ventilation during hypertensive resuscitation. Here are some key highlights:

The PAMPer Trial

The PAMPer trial examined the use of prehospital plasma in trauma patients and found significant survival benefits. This trial has important implications for trauma care protocols, emphasizing the potential of early plasma administration to improve outcomes.

The trial showed that administering plasma before hospital arrival can reduce mortality rates in severely injured patients. This finding supports the concept of damage control resuscitation, aiming to stabilize patients early and prevent coagulopathy, acidosis, and hypothermia—the lethal triad in trauma.

Bougie Use in the ED

Another focal point was the utility of bougies in emergency airway management. Evidence suggests that bougies can significantly improve first-pass success rates in difficult intubations, making them a valuable tool in the ED.

A study highlighted at the conference demonstrated that the use of a bougie, even in routine intubations, could increase the success rates for first-pass intubations. This is particularly important in prehospital settings and emergency departments where difficult airways are common.

Late Presenting Head Injury Patients

A paper from Hull explored the management of patients presenting with head injuries more than 24 hours post-injury. The findings indicated that these patients have a significant incidence of important findings on CT scans, suggesting that delayed presentations should not be underestimated.

This study challenges the conventional exclusion of late-presenting head injury patients from acute imaging protocols. It suggests that significant injuries can still be present and warrant immediate attention, even if the patient presents days after the initial trauma.

The Zero Point Survey

The Zero Point Survey, which emphasizes situational awareness, team dynamics, and environmental control before initiating the primary survey, was also highlighted. This approach can significantly enhance resuscitation efforts, ensuring a more organized and effective response.

The Zero Point Survey encourages clinicians to prepare mentally and physically before patient contact. By assessing the situation, assembling the right team, and ensuring the environment is conducive to optimal care, clinicians can improve outcomes and reduce errors in high-stress scenarios.

Responsible Volunteering Overseas

One of the most thought-provoking posts of the month came from Stefan Brisions, discussing the need for responsible volunteering overseas. Volunteering in low and middle-income countries can be incredibly rewarding, but it’s essential to approach it with the right mindset and framework.

The Ethics of Volunteering

Stefan emphasized the importance of volunteering within a system that has sustainability and benefits for all parties involved. There have been concerns about individuals volunteering for personal gain rather than genuine altruism. It’s crucial to ensure that our efforts are focused on creating lasting, positive impacts.

Volunteering should always aim to build local capacity rather than create dependency. This means working with local healthcare providers to enhance their skills and infrastructure, ensuring that the benefits of volunteering continue long after volunteers have left.

Volunteering Responsibly

If you're considering volunteering abroad, it’s vital to engage with established organizations that have a clear mission and ethical framework. This ensures that your contributions are meaningful and aligned with the needs of the local community. Our discussions with experts like Shweta Gidwani, Hooling Harrison, Jennifer Hulls, and Najee Rahman offer valuable insights into this complex issue.

Case Study: Volunteering in South Africa

Kat Evans, who works in Mitchell’s Plain in South Africa, shared her experiences at St Emlyn’s Live. Kat discussed the challenges of working in a resource-limited environment, particularly in managing trauma and toxicology cases.

Her insights into managing trauma in a high-volume, low-resource setting were eye-opening. Kat also shared fascinating details about the use of high doses of atropine for poisoning cases, highlighting the unique medical practices required in such environments.

Kat’s presentation underscored the value of structured volunteer programs that integrate volunteers into local healthcare systems, providing both valuable learning experiences and much-needed support to local healthcare providers.

The Future of SMACC: CODA

March also marked the end of an era with the final SMACC conference in Sydney. SMACC has been a cornerstone for many in the emergency and critical care communities, offering unparalleled opportunities for learning and networking. However, the spirit of SMACC lives on in its successor, CODA.

CODA: A New Beginning

CODA aims to build on SMACC's successes while addressing broader health issues such as vaccination, climate change, and healthcare inequality. The goal is to leverage the engaged community SMACC created to drive meaningful change on a global scale.

CODA plans to tackle these global health issues by bringing together a diverse group of professionals, including those outside the traditional medical fields. This interdisciplinary approach aims to create innovative solutions to some of the world’s most pressing health challenges.

Looking Ahead

While we bid farewell to SMACC, we look forward to the new opportunities CODA will bring. Its emphasis on tackling significant health challenges aligns with the evolving needs of the global healthcare community, promising an exciting future.

What to Expect from CODA

CODA will continue the tradition of high-quality content and dynamic presentations that SMACC was known for. However, it will also incorporate new elements focused on global health advocacy and interdisciplinary collaboration. Expect to see more discussions on how healthcare professionals can contribute to solving broader societal issues.

Additional Highlights from March

Critical Appraisal Nuggets (CANS) on P-values

We also introduced a mini podcast series called Critical Appraisal Nuggets (CANS) focusing on p-values, featuring myself and Rick Body. P-values are a common topic in exams and critical appraisal, and understanding them is crucial for interpreting medical research.

This less-than-ten-minute podcast provides a concise overview of p-values, helping clinicians and students alike grasp this important concept. By demystifying p-values, we aim to enhance our audience's critical appraisal skills, enabling better evidence-based practice.

Dual Coding in Medical Education

Nick Smith, a recent addition to the St Emlyn's team and a brilliant clinical educator, shared insights on dual coding. Dual coding involves using both verbal and visual information to enhance learning and retention.

Nick’s post emphasized how our brains struggle to process multiple streams of information simultaneously. Effective teaching and communication require a balance between verbal explanations and visual aids, ensuring that learners can absorb and retain information without being overwhelmed.

The Impact of Reboa in Trauma Care

Zaf Qasim, a great friend of ours over in the US, examined the impact of Resuscitative Endovascular Balloon Occlusion of the Aorta (Reboa) in trauma care. This post, based on a paper published in JAMA Surgery, analyzed Reboa success rates in civilian trauma using a US database.

The findings suggested that Reboa was associated with higher mortality rates compared to similar patients who did not receive Reboa. This raises important questions about patient selection and the overall benefits of Reboa in trauma care.

Zaf’s post highlighted the need for ongoing research and evidence to determine Reboa's true value. While there are compelling pathophysiological arguments for its use, the clinical outcomes must be scrutinized to ensure it is applied appropriately and effectively.

The Role of Evidence-Based Practice

At St Emlyn's, we prioritize evidence-based practice in all aspects of emergency medicine. The discussions around Reboa, p-values, and dual coding all reinforce the importance of using high-quality evidence to guide clinical decisions and educational strategies.

Final Thoughts

March 2019 was a month of incredible learning and growth. From managing complex ACHD patients to discussing the ethics of volunteering and exploring cutting-edge trauma research, we covered a wide range of topics that are crucial for emergency medicine professionals.

Stay Connected

As we move forward, we encourage you to stay connected with St Emlyn’s for more insights, updates, and discussions. Follow our blog, participate in our events, and join the conversation on social media. Together, we can continue to advance the field of emergency medicine and make a difference in the lives of our patients.

Thank you for joining us this month. Enjoy your practice, and we’ll be back with more great content in April. Have fun, stay safe, and keep learning!

Back in late 2018 we gathered in Manchester for the inaugural #stemlynsLIVE conference. Our friend Dr George Wills gave a great talk on Aortic Emergencies.

All emergency physicians know that it's all to easy to miss an aortic catastrophe. Listen to George's wisdom on common pitfalls and top tips to make you a better emergency clinician.

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Also check out these excellent #FOAMed resources.

• Subscribe to the blog (look top right for the link)
• Subscribe to our PODCAST on iTunes
• Follow us on twitter @stemlyns
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• Find out more about the St.Emlyn’s team

St. Emlyn's January Roundup: Key Insights and Innovations

Hello and welcome to the St. Emlyn’s Podcast. I’m Simon Carley, joined by Rick Body. Today, we’re bringing you our January roundup, sharing the most intriguing and impactful content we've covered this month. From reflecting on 2018 to exploring new guidelines and innovations in emergency medicine, we have a lot to discuss. Let’s dive in!

Reflecting on 2018: Transformational Reads and Achievements

As we started January, we reflected on 2018, a year filled with significant achievements and insights. One standout discussion was our review of key books that left a lasting impact. A personal favorite of mine is "Why We Sleep" by Matthew Walker. This book has been transformational for me, influencing how I live and advise others on health, well-being, and performance. The insights on sleep’s importance in education, creativity, and overall health are profound.

Rick, did anything from our 2018 review resonate with you?

Rick Body: Absolutely, Simon. The variety of books we discussed was impressive. It was enlightening to hear about others' achievements in 2018 and their goals for 2019. This exercise really focused my mind on what I hope to achieve this year.

Goals for 2019: Innovations and Personal Aspirations

As we moved from reflections to aspirations, we set our sights on exciting projects for 2019. One major highlight is the AI incubator for emergency care. This initiative aims to support academic careers and foster partnerships between data and industry to enhance medical technologies. It’s an exhilarating time for advancements in emergency care.

Rick is incredibly busy with groundbreaking work, particularly in diagnostics in Manchester. His research and speaking engagements are making waves in the medical community. For more details on these projects, check out the blog where all the information is comprehensively covered.

New Year’s Resolutions: Insights from Liz Crowe

We explored New Year’s resolutions with Liz Crowe, who offered a fresh perspective on well-being and resolutions. Instead of focusing on all-or-nothing goals, Liz suggests starting small and seeking rewards rather than punishments. This approach makes significant lifestyle changes more manageable and sustainable. Committing to resolutions publicly or with a friend can enhance accountability and success.

Rick, do you have any New Year’s resolutions?

Rick Body: It’s challenging to pinpoint one or two, but Liz’s advice on avoiding binary thinking is crucial. Recognizing progress rather than dwelling on setbacks can make a big difference.

Tetanus Guidelines: New Insights and Practical Applications

In January, we delved into updated tetanus guidelines, highlighting significant changes. Previously, a single booster in your early 20s was deemed sufficient, but the new guidelines recommend a 10-year booster. This change stems from the recognition that immunity wanes over time. Interestingly, point-of-care testing is now available to detect active tetanus immunization, allowing for more tailored booster decisions.

These updates are crucial for emergency physicians to ensure compliance with current standards and provide optimal patient care. The blog post simplifies these guidelines, making them accessible and easy to understand.

Excellence in Emergency Medicine: Claire Richmond’s Contributions

We featured Claire Richmond, a hero in the emergency medicine community. Claire, who works with Sydney HEMS, delivered an inspiring keynote at the St. Emlyn’s live conference. Her talk focused on excellence, performance, training, and development in retrieval medicine. She emphasized the importance of honesty, feedback, and continuous improvement.

For those aspiring to achieve self-actualization in emergency medicine, Claire’s insights are invaluable. We’ve shared the video and podcast of her talk, and we highly recommend checking them out.

Prognosticating Cardiac Arrest Outcomes: Dan Horner’s Research

Another highlight of January was Professor Dan Horner’s discussion on serum neurofilament light chains, a promising tool for prognosticating cardiac arrest outcomes. This research, stemming from the TTM trial, suggests that these biomarkers can provide early predictions about patient outcomes. Early identification of patients likely to have poor neurological outcomes can significantly impact family discussions, treatment decisions, and overall management.

This research is groundbreaking and holds potential for future clinical applications, although it’s not yet ready for immediate practice.

Celebrating Evidence-Based Medicine: Critical Appraisal E-Book

We’re incredibly proud of our journal club series at St. Emlyn’s, which advocates for evidence-based medicine. This series highlights the latest research, making it accessible and understandable. To celebrate the contributions over the past year, we’ve compiled an e-book available for free download. This resource is a testament to our commitment to advancing medical knowledge and practice.

Pre-Medication for Ketamine Sedation: Exploring New Research

One of the intriguing studies we covered this month examined pre-medication with midazolam or haloperidol for ketamine sedation. The randomized control trial suggested that pre-medication could reduce complications like abnormal behaviors and emergence phenomena. However, it also increased recovery time, requiring more resources and nursing time.

While the findings are interesting, they haven’t convinced us to change our current practice. However, it’s essential to stay informed about such research to make informed decisions in clinical practice.

HEMS and Traumatic Cardiac Arrest: Evaluating Outcomes

We also discussed the role of HEMS in improving outcomes for traumatic cardiac arrest. The study from the UK highlighted the high-level interventions provided by HEMS teams. However, it raised questions about the overall impact on patient survival. Of the 263 patients attended, only seven survived, and all had achieved ROSC before HEMS arrival. This data suggests that while HEMS interventions are critical, their direct impact on survival needs further evaluation.

This topic is sure to spark debate, and we appreciate the transparency of HEMS services in sharing their data and encouraging open discussions.

Looking Ahead: Plans for the Future

As we wrap up January, we’re excited about the plans for the coming months. Simon is heading to Jeddah for a significant event, and we’re considering hosting another St. Emlyn’s live conference and teaching course. We’re exploring innovative formats for medical conferences and welcome your ideas on how we can make these events even more impactful.

Support St. Emlyn’s: Keeping Education Free and Accessible

Since 2012, we’ve funded the blog and podcast out of our own pockets, but as our audience has grown, so have the costs. If you find our content valuable, please consider making a small donation or subscribing for regular contributions. Your support helps us keep St. Emlyn’s free and accessible to all.

Thank you for your time and continued support. Stay tuned for more updates, and as always, enjoy your emergency medicine practice and take care!

In this episode of the St. Emlyn's podcast, Rick Body and Charlie Reynard discuss an influential research project conducted by Dr. Reynard during his academic foundation program. The paper, titled 'Optimizing Antiplatelet Utilization in the Acute Care Setting,' explores decision-making under clinical uncertainty, specifically in emergency medicine for suspected acute coronary syndromes (ACS). Through systematic reviews and decision tree modeling, the research evaluates the benefits and risks of various antiplatelet therapies, such as Ticagrelor and aspirin versus Clopidogrel and aspirin. The findings reveal that Ticagrelor and aspirin are often more beneficial for patients with a greater than 8% probability of ACS, while Clopidogrel holds little to no place in current practice. The discussion opened up new questions about dynamic risk prediction and the importance of modeling to inform clinical decisions.

00:00 Introduction to the Podcast

00:26 Charlie's Research Background

00:52 Overview of the Research Paper

01:17 Decision Making Under Uncertainty

03:05 Systematic Reviews and Data Collection

03:46 Building the Decision Tree Model

04:48 Results and Key Findings

08:07 Implications for Clinical Practice

09:19 Future Directions and Conclusion

Barbra Backus joins Rick Body to discuss the origin, development and future of risk scores for ED patients with possible acute coronary syndromes. Two researchers at the top of their game, and  authors of the HEART and MACS scores.

Rick and Iain explore how the latest guidance about the use of high sensitivity troponin was developed and how far we can be assured that it is evidence based.

The NICE guidance is available here. http://www.nice.org.uk/guidance/dg15

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Understanding High Sensitivity Troponins: A Guide for Emergency Physicians

Welcome to the St. Emlyn's podcast. I'm Ian Beardsell and I'm Rick Bodden. This is part two of our troponin special where we delve deeper into high sensitivity troponins (hs-Tn) and their significance in emergency medicine. Today, we'll explore the nuances of hs-Tn assays and how they can enhance our work in the emergency department (ED).

Introduction to High Sensitivity Troponins

High sensitivity troponins (hs-Tn) have transformed how we detect and manage myocardial infarctions (MI) in emergency settings. Unlike traditional assays, hs-Tn tests detect much lower concentrations of troponin, a protein released during myocardial injury, allowing for earlier and more accurate detection of cardiac events.

Analytical Sensitivity vs. Diagnostic Sensitivity

Understanding the difference between analytical and diagnostic sensitivity is crucial. Analytical sensitivity refers to the assay's ability to detect low concentrations of troponin, whereas diagnostic sensitivity relates to the test's performance in diagnosing acute myocardial infarctions (AMI).

Key Points on Analytical Sensitivity:

• Detection Threshold: High sensitivity troponin assays can detect troponin in over 50% of healthy individuals.
• Precision: These assays have a coefficient of variation (CV) of less than 10% at the diagnostic threshold, ensuring consistent results.

Diagnostic Sensitivity:

• Improved Detection: Studies show hs-Tn assays have a higher diagnostic sensitivity (90-92%) compared to older assays (80-85%).
• Early Rule-Outs: This makes hs-Tn particularly valuable for ruling out AMI in patients presenting with chest pain in the ED.

High Sensitivity Troponin Assays: A Closer Look

To illustrate, let's focus on the Roche troponin T high sensitivity assay:

• 99th Percentile Cutoff: 14 nanograms per liter.
• Detection Range: Can detect levels as low as 3 nanograms per liter.
• Higher Readings: It's common for hs-Tn assays to give higher readings than older assays for the same sample, which affects the diagnostic threshold.

The Balance Between Sensitivity and Specificity

While hs-Tn assays improve sensitivity, they may reduce specificity:

• More Positives: Lowering the diagnostic threshold results in more positive results, increasing diagnostic sensitivity but reducing specificity.
• Predictive Value: For example, a positive hs-Tn T result at patient arrival has a specificity around 70% and a positive predictive value of 50%.

Using High Sensitivity Troponins in the Emergency Department

Early Rule-Out Protocols: The most significant advantage of hs-Tn assays is their potential to expedite the rule-out process:

• Zero and Three-Hour Protocols: Studies suggest that hs-Tn assays can effectively rule out AMI with samples taken at 0 and 3 hours after arrival, instead of the traditional 6-hour wait.
• Efficiency: This protocol can significantly speed up patient throughput in the ED, reducing congestion and wait times.

Understanding Deltas: Delta refers to the change in troponin levels between tests:

• Absolute vs. Relative Deltas: Absolute changes (e.g., an increase of 10 nanograms per liter) are often more reliable than relative percentage changes.
• Clinical Context: It's crucial to interpret deltas in the context of the patient's overall clinical picture.

Practical Considerations for Emergency Physicians

Incidental Troponin Elevations: With increased testing at the front door, incidental findings are inevitable:

• Low Pre-Test Probability: In patients with a low pre-test probability of AMI (e.g., mechanical falls), a positive hs-Tn result often does not indicate AMI.
• Clinical Judgment: Consider repeating the test and evaluating the patient's history and clinical presentation before making a decision.

Patients with Comorbidities: Troponin levels can be elevated in patients with various comorbidities:

• Age and Chronic Conditions: Older patients and those with conditions like LV dysfunction may have higher baseline troponin levels.
• Reference Ranges: Use broader reference ranges for patients with comorbidities, as suggested by studies from Paul Collins and colleagues.

Future Directions and Guidelines

Ongoing Research: Research and guidelines on hs-Tn usage are continually evolving:

• NICE Guidelines: Recommendations on using hs-Tn in clinical practice are expected to be published, providing clearer protocols for emergency physicians.
• Early Adoption: As new evidence emerges, early adopters must balance innovation with patient safety.

Point-of-Care Testing: While hs-Tn assays currently require large analyzers, point-of-care testing remains a goal:

• Future Developments: Advances in technology may eventually make hs-Tn testing available at the bedside, further streamlining ED workflows.

Conclusion

High sensitivity troponins represent a significant advancement in the early detection and management of myocardial infarctions in the emergency department. By understanding the nuances of analytical and diagnostic sensitivity, utilizing early rule-out protocols, and interpreting results within the clinical context, emergency physicians can leverage these assays to improve patient care. As always, ongoing research and adherence to evolving guidelines will be essential in optimizing the use of hs-Tn in clinical practice.

We hope this podcast helps you better understand the complexities and advantages of high sensitivity troponins. For more insights and updates, stay tuned to the St. Emlyn's blog and feel free to reach out with your questions and experiences. Together, we can continue to advance emergency medicine for the benefit of our patients.

Understanding Relative Risk, Absolute Risk, and Number Needed to Treat: A Guide for Emergency Medicine

Welcome back to the St. Emlyn’s podcast. I’m Iain Beardsell and joining me is Simon Carley. Today, we’re delving into the complex yet critical concepts of relative risk, absolute risk, and the number needed to treat (NNT) in the context of emergency medicine. These metrics are essential for understanding the effectiveness of treatments and making informed decisions in clinical practice.

The Importance of Understanding Risk Metrics

In emergency medicine, it’s vital to comprehend how different treatments impact patient outcomes. This understanding not only helps in communicating with patients but also aids in making better clinical decisions. Two key terms frequently encountered are relative risk reduction and absolute risk reduction.

Relative Risk Reduction vs. Absolute Risk Reduction

Imagine we are conducting a trial on a new drug for myocardial infarction (AMI) patients. Typically, 10% of AMI patients die within a month. If our new treatment claims a 50% relative risk reduction, it sounds impressive. However, understanding what this actually means is crucial. A 50% relative risk reduction translates to reducing the death rate from 10% to 5%. While this is significant, it's essential to recognize the difference between relative and absolute risk reduction.

Calculating the Number Needed to Treat (NNT)

The NNT is a valuable metric for understanding how many patients need to receive a particular treatment to prevent one additional adverse outcome. It’s derived from the absolute risk reduction. For instance, if a treatment reduces mortality from 10% to 5%, the absolute risk reduction is 5%. To calculate the NNT, divide 100 by the absolute risk reduction percentage. In this case, 100 divided by 5 equals an NNT of 20. This means we need to treat 20 patients to save one life.

Examples of NNT in Practice

Let’s consider some real-world examples. Tranexamic acid in trauma has an NNT of around 50, meaning we need to treat 50 patients to save one life. For aspirin in treating myocardial infarction, the NNT is also around 50. These figures highlight the effectiveness of these treatments in clinical practice.

Balancing Benefits and Harms

Understanding NNT is crucial, but it’s equally important to consider the number needed to harm (NNH). This metric indicates how many patients need to receive a treatment before one adverse effect occurs. For example, in trials involving starch solutions for sepsis, the NNH was found to be around 10-16. This means for every 10 to 16 patients treated, one additional death occurred. Balancing the benefits and harms is essential for making informed clinical decisions.

Example: Stroke Thrombolysis

In stroke thrombolysis, the NNT is around 8, meaning one in eight patients benefits from the treatment. However, the NNH is about 16, indicating one in 16 patients might experience a harmful outcome, such as intracerebral hemorrhage. Communicating these risks and benefits to patients is crucial for informed consent and shared decision-making.

The Role of Natural Frequencies

Using natural frequencies, such as “one in 100 people” or “one in 50 people,” helps in explaining risks and benefits in a more understandable way. For instance, saying “one in 100 people in your neighborhood” or “one person in a packed football stadium” can make the statistics more relatable.

Misdiagnosis and Its Impact

A key takeaway is that not every missed diagnosis leads to adverse outcomes. Often, treatments may have minimal benefit, and in some cases, they could cause harm. For example, the rush to administer clopidogrel in acute myocardial infarction might not always be necessary, given its relatively high NNT.

Applying These Concepts in Clinical Practice

Understanding and applying these concepts can change how we approach patient care. It allows us to prioritize interventions that provide the most significant benefit while minimizing potential harm. It also highlights the importance of taking time to ensure the right diagnosis and treatment, rather than rushing into potentially harmful decisions.

The Number Needed to Educate (NNE)

A fun and thought-provoking concept introduced in our discussion is the Number Needed to Educate (NNE). How many blogs or articles do you need to read before it changes your clinical practice? This metric emphasizes the importance of continuous learning and staying updated with the latest evidence-based practices.

Conclusion

In emergency medicine, understanding relative risk, absolute risk, and NNT is vital for making informed treatment decisions. These metrics help in balancing the benefits and harms of treatments, leading to better patient outcomes. By effectively communicating these risks and benefits to patients, we can ensure shared decision-making and improve overall patient care.

Read more at St Emlyns and on the accompanying blogpost

Exploring Diagnostic Testing in Emergency Medicine: A St Emlyn’s Perspective

Welcome back to the St Emlyn’s podcast! Today, we're diving deep into the world of diagnostic testing in emergency medicine, inspired by a recent discussion featuring our esteemed colleague Rick Boddie. This episode sheds light on the complexities of diagnosis, the probabilities involved, and the importance of shared decision-making with patients.

Understanding Diagnostic Probabilities

One of the critical points raised by Rick is the significance of understanding diagnostic probabilities. For instance, if a population has a 10% prevalence of a condition and we use a test with 90% sensitivity and 70% specificity, the post-test probability can be less than 2%. This scenario prompts the question: should we discharge a patient based on this probability or admit them for further testing?

In emergency medicine, our goal is to identify patients with serious conditions efficiently. Consider a thousand patients with chest pain; if the prevalence is 10%, around 100 of them will have the disease. With a 98% sensitivity test, we'll identify 98 patients but potentially miss two. However, this translates to missing only one in 500 patients overall, which is relatively low but still significant when considering the potential consequences of a missed diagnosis.

Consequences of Missed Diagnoses

The consequences of a missed diagnosis can vary. For some conditions, missing a diagnosis might not lead to severe outcomes. For instance, a small subarachnoid bleed might never recur, or an early-stage appendicitis could resolve on its own. In such cases, there might be no adverse consequences, and the patient could even benefit by avoiding unnecessary treatments.

However, for conditions like myocardial infarction (MI), the stakes are higher. Missing an MI can lead to severe complications, including cardiac arrest. Yet, it’s crucial to recognize that not every missed MI will result in a catastrophic outcome. Often, patients with missed diagnoses will experience further symptoms, allowing them another opportunity to seek medical attention.

Balancing Diagnostic Accuracy and Over-Investigation

In emergency medicine, we constantly balance the need for diagnostic accuracy with the risks of over-investigation. Over-investigating can lead to false positives, unnecessary treatments, and additional harm to patients. Therefore, it’s essential to adopt evidence-based guidelines and principles that help us make informed decisions without overburdening the diagnostic process.

One approach to achieving this balance is through shared decision-making with patients. Engaging patients in discussions about the risks, benefits, and potential harms of diagnostic tests can lead to better outcomes and increased patient satisfaction.

Shared Decision-Making in Practice

Shared decision-making is particularly valuable in complex cases, such as evaluating pregnant women for pulmonary embolism (PE). In these situations, the standard diagnostic pathway might involve tests that expose the patient and fetus to ionizing radiation. By discussing alternative diagnostic interventions, such as leg ultrasounds or modified VQ scans, we can involve patients in the decision-making process and tailor the diagnostic approach to their specific needs and concerns.

The Legal and Institutional Perspective

From a legal and institutional perspective, adhering to established guidelines and evidence-based practices provides protection for clinicians. If a missed diagnosis occurs despite following these principles, it is considered an acceptable risk within the diagnostic process. This understanding helps mitigate the fear of legal repercussions and allows clinicians to focus on delivering the best possible care based on current evidence.

Communicating with Patients

Effective communication with patients is a cornerstone of good medical practice. Instead of giving definitive statements like "you do not have this condition," it's more helpful to say, "we haven't found anything serious this time, but if you have any further symptoms or concerns, please come back." This approach not only sets realistic expectations but also encourages patients to seek further care if needed without feeling dismissed.

The Role of Technology in Diagnostics

Looking to the future, advancements in diagnostic technology could revolutionize emergency medicine. Imagine having a tool that could predict a patient's 30-day outcome or a "painometer" to measure pain levels accurately. Such innovations would enhance our ability to make precise diagnoses and provide targeted treatments, ultimately improving patient care.

Conclusion

Diagnostic testing in emergency medicine is a complex, nuanced process that requires balancing probabilities, understanding the consequences of missed diagnoses, and engaging in shared decision-making with patients. By adhering to evidence-based guidelines and maintaining open communication with patients, we can navigate these challenges effectively and deliver high-quality care.

At St Emlyn’s, we continuously strive to improve our diagnostic approaches and encourage open discussions about these critical topics. We invite you to share your thoughts and experiences with us on our website or via Twitter. Together, we can enhance our understanding and practices in emergency medicine.

Stay tuned for more insights and discussions in our next podcast episode. Until then, keep exploring, learning, and advancing the field of emergency medicine.

More listening about diagnosis

Podcast – Diagnosis in Emergency Medicine Part 1 – SpIN and SnOUT

Podcast – Diagnosis in Emergency Medicine Part 2 – Beyond a simple yes or no

Podcast – Diagnosis in Emergency Medicine Part 3 – The importance of prevalence

What is a Diagnosis?

A diagnosis is essentially a label that we put on a patient to indicate what they have, which then guides our treatment decisions. In the ED, our primary focus is on identifying life-threatening conditions. This approach often involves working backwards by first ruling out serious conditions before considering what a patient might actually have.

Initial Diagnostic Approach

As emergency physicians, our initial approach is to use tests with high sensitivity. These tests are designed to pick up anyone who might have the disease. Once we rule out the serious conditions, we look at tests with high specificity to confirm the diagnosis, as treatments often carry risks. For example, therapies such as thrombolysis come with significant risks, so we need to be fairly certain before proceeding, unlike less consequential treatments like wrist splints.

Understanding Probabilities in Diagnoses

When we say a patient has a diagnosis, we’re essentially saying it’s likely enough to treat. Conversely, when we say a patient doesn’t have a diagnosis, we mean it’s unlikely enough to withhold treatment. This probabilistic approach is vital in the ED and can be surprising to many people.

Case Study: Cardiac Chest Pain

Let’s apply this to a patient with cardiac-sounding chest pain. Our goal is to either rule out or confirm the disease and start appropriate treatment. We start with specific tests to rule in a diagnosis, such as an ECG. A positive ECG with significant ST segment changes indicates a high likelihood of disease, warranting immediate treatment. This approach quickly sorts out high-risk patients.

For patients with normal or near-normal ECGs but still concerning symptoms, we need sensitive tests to ensure we don't miss anyone with myocardial disease. About 10% of these patients might have underlying issues, so we need to ensure our tests are sensitive enough to catch these cases.

Using Prevalence and Pre-test Probability

To decide if a patient has the disease, we must consider the prevalence or pre-test probability in our population. For example, in patients with normal ECGs and no alarming history, the pre-test probability might be around 10%. This isn’t low enough to rule out the disease but also not high enough to justify treatment without further testing.

Diagnostic Processes in the ED

We use a step-by-step diagnostic process. Starting with the most specific tests to rule in a diagnosis, we then use sensitive tests like high-sensitivity troponin to rule out diseases. High-sensitivity troponin tests are great for ruling out diseases due to their sensitivity. If the test is negative, we can be confident the patient doesn’t have myocardial damage. If the test is positive but not dramatically high, we may need additional tests to confirm the diagnosis.

Each diagnostic step adjusts our patient’s probability of having the disease. Our goal is to reach a probability low enough to safely rule out the disease or high enough to justify treatment. This process is continuous, and we apply it to every patient, whether they have chest pain or another symptom like a headache.

Understanding Likelihood Ratios

We often use likelihood ratios to interpret diagnostic tests. A positive likelihood ratio increases the probability of the disease, while a negative likelihood ratio decreases it. For example, a high-sensitivity troponin test is excellent at ruling out myocardial infarction because of its high sensitivity, though it’s not as good at ruling in due to lower specificity.

Optimising Diagnostic Tests

Diagnostic tests like troponin can be optimized by adjusting the threshold levels. For instance, a higher threshold might improve specificity and thus be better at ruling in the disease, while a lower threshold improves sensitivity, making it better at ruling out the disease. This principle applies to various tests, including white cell counts and amylase levels.

Continuous Assessment and Reassessment

In the ED, we continuously assess and reassess patients. Each diagnostic step, whether it’s asking a question about symptoms or ordering a lab test, adjusts our understanding of the patient’s condition. This iterative process helps us make informed decisions about treatment and ensures that we don’t miss critical diagnoses.

Applying the Approach to Different Symptoms

This diagnostic approach isn’t limited to chest pain. Whether a patient presents with a headache, abdominal pain, or any other symptom, we apply the same principles of sensitivity, specificity, and likelihood ratios. Each question we ask and each test we perform helps refine our assessment and move closer to a definitive diagnosis.

Conclusion

Mastering diagnostic skills in the ED involves understanding and applying probabilities, using specific and sensitive tests effectively, and continuously reassessing the patient’s condition. By focusing on these principles, we can make more accurate diagnoses, provide appropriate treatments, and ultimately improve patient outcomes.

More listening about diagnosis

Podcast – Diagnosis in Emergency Medicine Part 1 – SpIN and SnOUT

Podcast – Diagnosis in Emergency Medicine Part 2 – Beyond a simple yes or no

Podcast – Diagnosis in Emergency Medicine Part 3 – The importance of prevalence

Patients often come to us with the fundamental question: "Doctor, what's wrong with me?" Our goal is to provide an answer through history, examination, and tests. Let's explore what it means to make a diagnosis in emergency medicine.

The Role of Diagnosis in Emergency Medicine

In day-to-day practice, making a diagnosis often means applying a label to a patient. This label helps us decide on the next steps, whether to treat or reassure and send them home. In emergency medicine, we frequently focus on ruling out serious conditions rather than confirming them. This approach allows us to prioritize immediate life-threatening issues and manage resources effectively.

Working Backwards: Ruling Out Serious Conditions

Our primary concern in emergency medicine is to identify conditions that can kill quickly, often within hours. Therefore, we start by ruling out the most serious conditions first. Diagnostic tests, including history and physical examination, play a crucial role in this process. Every question we ask and every examination we perform are part of our diagnostic strategy, aiming to rule out or confirm serious illnesses.

Sensitivity and Specificity in Diagnostic Testing

Understanding diagnostic tests involves two key concepts: sensitivity and specificity.

• Sensitivity refers to a test's ability to correctly identify those with the disease (true positives). High sensitivity means that a negative test result is reliable for ruling out the disease.
• Specificity measures a test's ability to correctly identify those without the disease (true negatives). High specificity means that a positive test result is reliable for confirming the disease.

For example, a D-Dimer test for thrombotic disease is highly sensitive. It picks up most cases of the disease but also includes some false positives. Conversely, a highly specific test like jaw claudication for temporal arteritis has very few false positives but isn't useful as a broad screening tool because only a small percentage of patients with the disease exhibit this symptom.

The Importance of Probability and Risk

In emergency medicine, we rarely achieve 100% certainty in diagnosis. Tests with 98% sensitivity, for instance, still miss 2% of cases. This level of uncertainty is part of our practice, and we must communicate it effectively to patients. Explaining the probabilistic nature of diagnosis helps patients understand the limitations of medical testing and the importance of follow-up if symptoms persist or worsen.

Balancing Diagnosis and Treatment

The consequences of diagnosing and treating a condition vary. For life-threatening conditions like myocardial infarction (MI), the treatment involves significant interventions such as thrombolysis or PCI, which carry their own risks. Therefore, we need a high degree of certainty before initiating such treatments. In contrast, diagnosing a viral sore throat, which requires minimal intervention, demands less certainty.

Continuous Learning and Improvement

Reflecting on our diagnostic processes is crucial for improvement. Recognizing that we work in a probabilistic environment helps us balance the need for thorough investigation with the risk of over-testing. By continuously learning and refining our approach, we can enhance patient care and outcomes.

Favourite Diagnostic Tools

To conclude, let's talk about our favorite diagnostic tools. Personally, I appreciate the value of ultrasound in the resuscitation room, especially for diagnosing pneumothorax in trauma patients. It's a quick, effective tool that guides immediate intervention. Simon, on the other hand, highlights the D-Dimer test. Despite its controversial reputation, it serves as a prime example of a test that, when understood and used correctly, can be incredibly valuable.

We hope this podcast has provided some insight into the complexities and nuances of diagnosis in emergency medicine. Stay tuned for our next episode, where we'll delve deeper into the probabilistic nature of diagnosis and how we make informed decisions in the emergency department. Until then, take care and continue to enjoy your practice in emergency medicine.

More listening about diagnosis

Podcast – Diagnosis in Emergency Medicine Part 1 – SpIN and SnOUT

Podcast – Diagnosis in Emergency Medicine Part 2 – Beyond a simple yes or no

Podcast – Diagnosis in Emergency Medicine Part 3 – The importance of prevalence