Dr. Jeff Hersh provides information on how ultrasound might be used in a global health crisis including deep dives on lung, heart and shock evaluation.
The Value of Point of Care Ultrasound
With the growing outbreak of the novel coronavirus (COVID-19) worldwide, healthcare providers are facing unprecedented challenges and working conditions. Ultrasound has been found to help providers manage the treatment plans of COVID-19 patients due to its portability, cleanability, and bedside imaging capabilities.
To better understand the use point-of-care Ultrasound during a global health crisis, we asked Dr. Jeff Hersh, Chief Medical Officer of GE Healthcare, to provide guidance and resources for clinicians. This is an excerpt of a full education webinar. To watch the full video and educational webinar, click here.
What ways can ultrasound be used for lung examination for these types of patients?
Dr. Hersh: When it comes to lung segments, it’s important as you’re doing an exam, you do it in a consistent way, so you don’t forget to look at something in a way that is reproducible. Especially because you may be doing serial exams as you manage your patients over the course of times.
Identifying the different lung segments and having a tool that will help you walk through those lung segments is extreme useful, for example, a patient where you can see B-lines. The patient comes in with respiratory distress and congestive heart failure.
There is some new research that shows in atypical pneumonia, especially the coronavirus (COVID-19), may actually have B-lines and confluence of B-lines in what some people call a waterfall sign. This is interesting to do as part of your overall evaluation. As I mentioned, this is also very useful if you’re doing continuity care in a patient that has shock to see if you’ve been possibly a little over-aggressive in the fluid resuscitation.
Being able to identify B-lines is important, and of course if your patient comes in and they have fever and they’re coughing and they have some shortness of breath or respiratory distress, it doesn’t mean they have the new corona, COVID-19 virus. They could easily have a community-acquired pneumonia or another bacterial pneumonia. Evaluating your patient for pneumonia is extremely important and ultrasound has great utility for being able to do that.
Ultrasound is also sensitive to identify pneumothorax. This is going to be useful for a patient with pneumothorax for whatever the cause, whether it be a patient who’s been intubated requiring PEEP and has in the course of their therapy acquired pneumothorax. By looking at what we call the lung point, you can identify pneumothorax. But by looking at where the lung point is, it may give you an idea of how big the pneumothorax is, which may help guide your therapeutic decisions--specifically do you need to put a chest tube in right away, or are there other interventions that you may want to utilize?
Pleural effusion can happen for many reasons. If you’re able to identify a pleural effusion in a patient who may have it as an exasperation due to shortness of breath, it is not only useful to know they have the pleural effusion, but you would also be able to use point-of-care ultrasound to guide your pleural tap. That would be useful as you do your therapeutic intervention in a patient who may need a pleural tap to improve their respiratory status.
What ways can ultrasound be used for cardiac examination for these types of patients?
Dr. Hersh: Starting with ventricular function, patients may come in with a depressed ventricular function for many reasons. They may have cardiomyopathy; they may have had myocardial infractions in the past; they may have a baseline decrease in their overall injection fraction. Being able to assess their overall ventricular function is an extremely important part of the management of a critically ill patient. This is an extremely important function of a patient who for example, may be in septic shock.
There are other aspects of the cardiac evaluation that may be useful in certain patients. For example, valvular disease. Identifying valvular disease and identifying exactly how significant that is. It may be that is exasperating certain parts of your evaluation and may be an important aspect as you make your therapeutic decision. So, knowing what valvular function or disfunction a patient has may be important.
What ways can ultrasound be used for shock evaluation for these types of patients?
Dr. Hersh: An important use of baseline evaluation, while using point-of-care ultrasound in a patient that may be presentation a septic shock, is evaluating shock as whole.
The way I think of shock is, I always start by looking at what is the cause of shock. Now, if it’s a patient that comes in, and you suspect they’re having septic shock, the clinical picture may guide you, but there are so many reasons that a patient may present in shock. So, in general, a patient who comes in in shock may require a FAST exam.
At a high level, there could be some possible causes. One of the possible causes, especially in a patient who presents with the appropriate clinical scenario, is--for example, a patient who comes in with shock after a motor vehicle accident, having hemorrhagic shock--would be extremely suspicious. Being able to do a FAST exam and looking for free fluid in the abdomen could lead you to recommending a very early surgical intervention for that patient.
Being able to look for free fluid is part of the FAST exam; it is an important part of the exam. You also may be interested in looking for a pleural effusion. Once again, it may be they have the pleural effusion from a lung injury, and if this is a trauma patient (they may have a pneumothorax), you’d be able to see that on your point-of-care ultrasound.
Once you understand the epidemiology of the patient’s shock, the next step is to try and manage them. Point-of-care ultrasound can also be valuable in helping you monitor IVC collapsibility, fluid management, and lung B-lines for example.
Additional Resources & Guidelines
ACEP Guidelines - Scope Excerpts
- “EUS core applications are being integrated into cardiopulmonary and non-invasive hemodynamic monitoring into critical care scenarios. Dual-trained physicians in emergency medicine and critical care are leading the application, education, and research of US for critically ill patients, and have significant leadership in advancing US concepts in multidisciplinary critical care practice. Advanced cardiopulmonary US application are being integrated into critical care practice.”
International arena including field, remote, rural, global public health and disaster situations
- “Ultrasound (US) has become the primary initial imaging modality in disaster care. US can direct and optimize patient care in domestic and international natural disasters such as tsunami, hurricane, famine or man-made disasters such as battlefield or refugee camps. US provides effective advanced diagnostic technology in remote geographies such as rural areas, developing countries, or small villages which share the common characteristics of limited technology (ie, x-ray, CT, MRI), unreliable electrical supplies, and minimally trained health care providers. US use in outer space is unique as the main imaging modality for space exploration and missions. Ultrasound has also been used in remote settings such as international exploration, mountain base camps, and cruise ships. The increasing portability of US machines with increasing image resolution has expanded the use of emergent imaging in such settings. See ACEP linked resources at www.globalsono.org”
Other community resource references
Impact of Pocket Ultrasound Use by Internal Medicine House Staff in the Diagnosis of Dyspnea
Filopei & Kory, Beth Israel, Journal of Hospital Medicine
Residents participating in lung ultrasound training with a pocket ultrasound device showed improved diagnostic accuracy in their evaluation of patients with dyspnea. Two residents who received extended training had shown a total increase in diagnostic accuracy. Read more: https://www.ncbi.nlm.nih.gov/pubmed/?term=24891227
Rapid evaluation by LCI integrated US for differentiating HF from pulmonary disease in the emergency setting - Cardiovascular Ultrasound Kajimoto & Abe, Cardiovascular Ultrasound
This study demonstrated that rapid evaluation by lung-cardiac-IVC (LCI) integrated ultrasound is extremely accurate for differentiating acute dyspnea due to AHFS from that caused by primary pulmonary disease in the emergency setting. Read more:
Does the integration of personalized US change patient management in CC medicine? Observational trials - Breitkreutz & Seeger, Emergency Medicine International
The authors proposed the development of novel ultrasound-based clinical pathways by integration of PersUS. Read more:
Imaging Congestion with a Pocket Ultrasound Device: Prognostic Implications in Patients With Chronic Heart Failure - Gustafsson & Johansson 2015, Journal of Cardiac Failure
Signs of pulmonary congestion could be demonstrated with the use of a handheld ultrasound device. When signs found, these had a significant prognostic impact in clinically stable HF.