Ultrasound-guided supra-inguinal fascia iliaca block: a cadaveric evaluation of a novel approach

Background

Regional anesthesia of the fascia iliaca is well-documented to be a successful way to control acute pain from hip fractures in the emergency department, particularly in those patients at high risk of complications from repeated doses of IV opioids. However, the majority of existing descriptions on technique for performing fascia iliaca blocks focus on approaching from inferior to the inguinal ligament, relying on supra-inguinal spread to block the lateral femoral cutaneous nerve in the iliac fossa. This study aims to investigate the utility in performing suprainguinal injection of anesthetic agents directly into the iliac fossa to provide regional anesthesia.

Ultrasound-guided supra-inguinal fascia iliaca block: a cadaveric evaluation of a novel approach

Clinical Question

Does injecting dye superior to the inguinal ligament provide significant uptake of dye in the femoral, LCFN, and ilioinguinal nerves in cadaveric models?

Methods & Study Design

• Design

This is an informational study made to illustrate the utility of an alternative supra-inguinal approach for providing regional anesthesia in those patients presenting with acute hip or knee pain.

• Population

Bilateral injections of 20 mL of 0.25% aniline blue dye were administered to six unembalmed cadavers, for a total of 12 injections available for analysis.

• Intervention

Bilateral injections of 20 mL of 0.25% aniline blue dye were administered to six unembalmed cadavers via an ultrasound guided approach, and dye uptake was analyzed in anatomic nerve distributions.

Steps of superior approach to fascia iliaca block:

Place sterile probe over the inguinal ligament, close to the anterior superior iliac spine
Orient linear probe in parasagittal oblique orientation (superior aspect facing medially)
Rock the probe so beam faces laterally to enhance fascia iliaca
Move probe infero-medially along the line of inguinal ligament until femoral artery is imaged
Moving probe supero-laterally helps identify anterior inferior iliac spine (site of rectus femoris attachment)
As you move laterally, you see “rising” of ilium towards transducer
Identify deep circumflex artery 1-2cm superficial to fascia iliaca
Needle introduced 2-4cm inferior to inguinal ligament, and advanced through the fascia iliaca at the level of inguinal ligament.
“pop” as needle passes through fascial iliaca and into the iliacus muscle
Needle withdrawn to the fascia, and position confirmed by 1cc of local anesthetic.
Injection of fluid produces a“lens”that appears. The fluid should then hydro-dissect as it migrates into the iliac fossa
End point is when local anesthetic passes freely superiorly over the iliacus muscle and into the iliac fossa.

• Outcomes

Dye uptake in the femoral, lateral femoral cutaneous nerve, and ilioninguinal nerves after supra-inguinal injection.

Results

- There was extensive spread of dye identified in the iliac fossa. (50 to 144mm of spread)
- 10 out of 12 injections also resulted in spread into the thigh along the femoral nerve
- The femoral nerve was surrounded by dye in all cases
- The LFCN was identified bilaterally in 5 cadavers, but one cadaver lacked both LFCN. LCFN was surrounded by dye in all cases in which it was present.
- It is important to realize that the ilioinguinal nerve has significant anatomic variation. The ilioinguinal nerve passed over iliac crest onto iliacus muscle and re-emerged into the abdominal wall anteriorly in 8 cases. In the other four cases it remained in the abdominal wall. It was stained blue 7 out of 8 times in this procedure as it passed over iliac crest.

Strength & Limitations

- There was no comparison group in this study (supra-inguinal approach was used in all cases).
- There were significant anatomic variations between cadavers. One cadaver was found to have no lateral femoral cutaneous nerve. There were also significant anatomic variations in positioning of the ilioinguinal nerve.
- Throughout the article, there were multiple references that the authors institution has performed over 150 supra-inguinal fascia iliata blocks without any short term complications, however no retrospective data was available in the article to confirm this.
- Low sample population (6 cadavers, 12 nerve blocks)

Authors Conclusion

“Our cadaveric dye-injection study confirms that the ultrasound-guided supra-inguinal approach result in significant spread of injectate with simultaneous involvement of both the femoral nerve and LFCN, in the iliac fossa, in the all the cadavers in which we identified theses nerves by dissection.”

Our Conclusion

This article outlines an interesting alternative approach to providing regional anesthesia for acute pain control of the hip or knee. The majority of existing descriptions on technique for performing fascia iliaca blocks focus on approaching from inferior to the inguinal ligament, relying on supra-inguinal spread to block the lateral femoral cutaneous nerve in the iliac fossa. This study demonstrates consistent bathing of the LFCN and femoral nerve with dye in cadaveric subjects with a supra-inguinal approach. However, this study does not directly demonstrate superior efficacy of the suprainguinal approach when compared to infrainguinal fascia iliaca block. Further patient-oriented studies would be needed to make such a suggestion.

The Bottom Line

Ultrasound guided suprainguinal fascia iliaca injection of dye in cadaveric subjects shows consistent and significant uptake of injectate of the femoral nerve and LFCN in the iliac fossa. Further studies are needed to show if this provides improved analgesia as compared to the conventional infrainguinal approach.

Authors

This post was written by Casey Smith, MD. Review and further commentary was provided by Danika Brodak, MD, Emergency Ultrasound Fellow at UCSD and Amir Aminlari, MD, Ultrasound Faculty at UCSD.

References

Hebbard P, Ivanusic J, Sha S. Ultrasound-guided supra-inguinal fascia iliaca block: a cadaveric evaluation of a novel approach. Anaesthesia. 2011;66(4):300‐305. doi:10.1111/j.1365-2044.2011.06628.x

April 24, 2020July 21, 2020

Case # 18: Respiratory Distress: It’s not all COVID.

During the COVID-19 pandemic, a 67 year old woman is brought to the ER by family for respiratory distress and altered mental status. She was alert but not oriented and unable to answer questions on arrival with moderate respiratory distress. Family stated that she had a history of asthma and takes "other" medications, but where otherwise unaware of her past medical history. She had been using her inhaler without relief and has not had any sick contacts, cough or fever.

Vitals: T: 98.7, HR: 112, BP: 190/110, RR: 40, SpO2 80 on RA

She was in moderate respiratory distress, crackles on exam, no pitting edema. She was placed on a non-breather (avoiding NIPPV) and a thoracic plus cardiac ECHO was preformed.

After reviewing the images, what would you do next?

Answer and Learning Points

Answer

The images would suggest that this patient is most likely suffering from heart failure with an acute exacerbation. There are diffuse B-lines, obvious decrease contractility and a dilated IVC. These images are not typical of COVID-19 infections, which have pleural thickening and scattered b-lines (see COVID section). This patient was put on a nitro drip and given diuretics, with a significant improvement in her respiratory status in the ER. She ultimately tested COVID negative and was discharged from the hospital after aggressive diuresis.

During the same shift, numerous COVID-19 positive patients were seen. Below are images of COVID-19 cases for comparison and more can be found at The POCUS Atlas.

While the sensitivity and specificity of ultrasound to diagnosis COVID-19 has yet to be determined, this case illustrates how alternative findings can still impact clinical care and potentially avoid intubation.

COVID +

On the same shift, numerous COVID-19 patients were also seen, with variable pre-test probability. ECHO for these patients would not reveal an alternative diagnosis (such as our CHF case). There were however some classic findings on ultrasound. Note below two patients with thoracic scans. There are scattered B-lines (unlike our CHF patient, who had diffuse B-lines). There is also pleural thickening and at times an irregular pleural border.

Author

Sukhdeep Singh, MD. Clinical Faculty, UCSD Department of Emergency Medicine. Director of POCUS, El Centro Regional Medical Center.

References

DeRose et al, How to Perform Pediatric Lung Ultrasound Examinations in the Time of COVID‐19. Journal of Ultrasound in Medicine. 22 April 2020.
The POCUS Atlas. http://www.thepocusatlas.com/covid19

November 9, 2018July 21, 2020

Point-of-Care Ultrasonography for Evaluation of Acute Dyspnea in the ED

Background

Dyspnea is a common presenting symptom in the emergency department, and early diagnosis of underlying disease pathology is crucial in rapid intervention and treatment. Laboratory and radiological tests aid in the diagnosis, but often these results take time.^1-3 Additionally, chest radiographs and chest CTs, the most common radiological tests in the evaluation of dyspnea, have several disadvantages including radiation risks and high costs. Unlike these modalities, point-of-care ultrasound (PoCUS) is cheap with no radiation risk, highly accurate, and has better sensitivity in detecting pneumothorax, pneumonia, and pleural effusions than CXR.^4-7 In addition to being accurate and reliable, PoCUS can be performed rapidly to aid in early diagnosis and treatment of patients.

Point-of-Care Ultrasonography for Evaluation of Acute Dyspnea in the ED

Clinical Question

What is the feasibility and diagnostic accuracy of PoCUS for the management of acute dyspnea in the ED?

Methods & Study Design

Design:

Prospective, blinded, observational study

Population:

This study was conducted at Careggi University Hospital, a university-affiliated teaching hospital.

Inclusion Criteria:

Patients over the age of 18 with acute dyspnea of any degree.

Exclusion Criteria:

Patients with dyspnea of traumatic origin, and those that were discharged from the emergency department after evaluation.

Intervention:

All patients were primarily assessed by 2 separate emergency physicians with vital signs, history, physical exam, and EKG.

One physician performed a Lung, Cardiac, and IVC PoCUS.

One physician performed a standard workup using any combination of Chest X-Ray, Chest CT, Echocardiogram, labs, or Arterial Blood Gas.

Both physicians were asked to make up to 2 diagnoses based on their results.

Possible diagnoses: Heart Failure, Acute Coronary Syndrome, Pneumonia, Pleural Effusion, Pericardial Effusion, COPD/asthma, Pulmonary Embolism, Pneumothorax, ARDS/ALI, Other.

Outcomes

Primary:

Accuracy of diagnosis:

Follow-up chart review determined the reference diagnosis. Results were compared to the diagnosis obtained from the ultrasound group and the standard workup group.

Secondary:

Time to final diagnosis for both groups was recorded.

Time for Ultrasound completion was recorded.

Results

3,487 total patients → 2,683 included in study

Average time to complete US: 7±2 min

Average time to Diagnosis:

Ultrasound: 24 ± 10 minutes

ED: 186 ± 72 minutes

Variable	Sensitivity - Ultrasound	Sensitivity - Standard
Heart Failure	88 (85.1-90.6)	77.3 (73.7 – 80.6)
COPD/asthma	86.6 (84.2-89.2)	92.2 (90.1-94)
Pulmonary Embolism	40 (30.1-50.6)	90.5 (82.8-95.6)

Point-of-care ultrasound had an increased sensitivity in detecting heart failure compared to standard workup.
Point-of-care ultrasound had a decreased sensitivity in diagnosing COPD/asthma and pulmonary embolism compared to standard workup.

There were no differences in the sensitivity or specificity of ultrasound vs. standard workup in all other diagnoses.

Strength & Limitations

Strengths

Adequate sample size obtained for most diagnoses.

Gold standard diagnosis was reviewed by two separate emergency medicine physicians.

Limitations

Ultrasound sonographers focused only on those patients with dyspnea, while the treating physicians were responsible for other patients in the ED.

This likely increased the time to diagnosis for emergency physicians in the standard workup group.

Patients discharged from the hospital were not included in study.

Average age of patient population was 71, but patients 18 and over were accepted.

ARDS patient studies were underpowered.

Authors Conclusion

“Integrated ultrasound methods could replace the current first diagnostic approach to patients presenting with dyspnea, allowing a drastic reduction in costs and diagnostic times.”

Our Conclusion

Point-of-Care Ultrasound in patients with dyspnea provides us with quick information to begin treatment before other laboratory and radiological tests become available. While this study showed that ultrasound was superior to the standard workup in detecting heart failure, it was slightly inferior to the standard workup in detecting COPD/asthma, and significantly inferior to standard workup in detecting pulmonary embolism. The authors speculated that with the inclusion of a DVT ultrasound study would improve the sensitivity for detecting PEs greatly.

There have been other studies demonstrating increased sensitivity using ultrasound in patients to diagnose pneumonia and pleural effusions compared to chest x-ray. This study contributed to our knowledge of the accuracy of ultrasound in undifferentiated dyspnea by demonstrating its accuracy in these other important diagnoses. The study shows that PoCUS can guide and the emergency physician’s workup, help risk-stratify, can help us to begin treatment quickly, and improveflow and efficiency in the ED.

The Bottom Line

Although PoCUS won’t replace a standard workup in many cases, PoCUS can rapidly and accurately aid in determining the underlying diagnosis in patients presenting to the ED with undifferentiated dyspnea and may lead to quicker treatment times and improved flow in the emergency department.

Authors

This post was written by Marissa Wolfe, MS4 at Stony Brook University. Review and further commentary was provided by Amir Aminlari, MD, Ultrasound Faculty at UCSD.

References

Mulrow CD, Lucey CR, Farnett LE. Discriminating causes of dyspnea through clinical examination. J Gen Intern Med. 1993;8(7):383-392.
Schmitt BP, Kushner MS, Wiener SL. The diagnostic usefulness of the history of the patient with dyspnea. J Gen Intern Med. 1986;1(6):386-393.
Nielsen LS, Svanegaard J, Wiggers P, Egeblad H. The yield of a diagnostic hospital dyspnoea clinic for the primary health care section. J Intern Med. 2001;250(5):422-428.
Lichtenstein D, Mezière G. Relevance of lung ultrasound in the diagnosis of acute respiratory failure: the BLUE protocol. Chest. 2008;134(1):117-125.
Reissig A, Copetti R, Mathis G, et al. Lung ultrasound in the diagnosis and follow-up of community-acquired pneumonia: a prospective, multicenter, diagnostic accuracy study. Chest. 2012;142(4): 965-972.
Zanobetti M, Poggioni C, Pini R. Can chest ultrasonography replace standard chest radiography for evaluation of acute dyspnea in the ED? Chest. 2011;139(5): 1140-1147.
Nazerian P, Volpicelli G, Vanni S, et al. Accuracy of lung ultrasound for the diagnosis of consolidations when compared to chest computed tomography. Am J Emerg Med. 2015;33(5):620-625.

August 14, 2017July 22, 2020

Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis

Background

The chief complaint of “dyspnea” represents a very large cohort of patient who present to the emergency department. While acute heart failure (AHF) is a very common diagnosis in the setting of dyspnea, the diagnosis remains challenging when the emergency physician is presented with the undifferentiated dyspneic patient. Interestingly, emergency physicians have varied approaches to the work up and diagnosis of these patients and it is not clear as to which diagnostic element is most crucial in confirming the diagnosis of AHF. Spoiler: Ultrasound proves to be quite useful.

Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis‌

Clinical Question

What are the operating characteristics of the diagnostic elements available to the emergency physician for diagnosing acute heart failure?

Methods & Study Design

Design
- This is a systematic review evaluating index test operating characteristics in diagnosing AHF. A medical literature search was performed using PubMed and EMBASE, evaluating peer-reviewed published papers from 1965 through 2015
- Individual systematic reviews for each index test were conducted by two separate physicians and thereafter reconciled to obtain a comprehensive set of studies on the topic. These were then screened against the inclusion/exclusion criteria for final inclusion into the meta-analysis
- The reference standard used was a final diagnosis of AHF based on review of clinical data by independent reviewers who were blinded to the study’s primary index test
Population
- All studies included involved patients presenting to the emergency department (ED) with the chief complaint of “dyspnea.”
Outcomes
- Pooled sensitivities, specificities and likelihood ratios (LRs) of index tests for diagnosing acute heart failure in patients presenting to the ED with dyspnea
- They specifically looked at the following index tests in evaluation of AHF: history and physical exam, ECG, chest x-ray, BNP and NT-ProBNP, lung ultrasound (US), and bedside echocardiography
Excluded
- Patients presenting to urgent care with dyspnea
- Patients with chronic, compensated heart failure
- Studies focusing on prognosis or therapeutics and not the diagnosis of AHF
- Studies with ultrasound images that were not obtained and interpreted by emergency physicians

Results

- History and Physical: S3 most specific finding for AHF (+LR 4)
- ECG: Found to be insensitive and unspecific for diagnosing or ruling out AHF
- CXR: Pulmonary edema was the most specific finding (LR + 4.8). All other imaging findings were insensitive for ruling out heart failure
- BNP and NT-Pro-BNP: Quite sensitive for ruling out AHF at a threshold of 100/300pg/dL
- Lung Ultrasound:
  - Presence of >3 B-lines in >2 lung fields is very specific for the presence of AHF
  - Lack of this also sensitive for ruling out acute heart failure
  - High inter-rater reliability
- Bedside Echo
  - ED provider evaluation of systolic function had high inter-rater reliability with the ultimate ejection fraction assessed by cardiologists on formal echo
  - Restricted Mitral Inflow very specific for ruling in diastolic AHF in patients with preserved systolic function

Strengths & Limitations

Strengths
- Very thorough analysis of the operating characteristics of a plethora of diagnostic elements and sub-elements available to the emergency physician in diagnosing AHF
- Authors didn’t exclude comorbidities, etiology of AHF or if there was an underlying arrhythmia which increased the generalizability of their results
- All data was screened and evaluated by two separate physicians
Limitations
- The reference standard was a final diagnosis of AHF made by physicians in retrospective fashion which weakens this as a “gold standard.”
- The authors did not specifically evaluate or reconcile whether the heart failure was left or right sided
- Each of the tests or test characteristics were assessed in isolation to determine the likelihood of heart failure. The likelihood of AHF when considering multiple index tests was not assessed
- As in all large meta-analyses, some spectrum bias may exist as inclusion/exclusion criteria varied among included studies. However, ome of this heterogeneity is likely countered by the pooled analysis and is unlikely to drastically change the calculated LRs

Author's Conclusions

"Bedside lung US and echocardiography appear to the most useful tests for affirming the presence of AHF while natriuretic peptides are valuable in excluding the diagnosis."

Our Conclusions

This is one of the most thorough studies available to assess the likelihood that a patient presenting to the emergency department has acute heart failure based on an index test. There are many old standby diagnostic modalities available to emergency physicians including the history, physical exam, and chest x-ray. Unfortunately, these diagnostic elements are relatively non-specific in establishing that a patient’s acute symptoms are likely or unlikely due to heart failure. BNP and NT Pro BNP are quite useful in ruling out heart failure however these tests take time to result. Ultrasound is rapidly becoming a fundamental tool in every emergency physicians tool belt and should be utilized alongside the primary patient assessment in determining the likelihood that a patient has heart failure. The presence or absence of B lines (>3 in at least 2 fields) is quite specific for ruling in heart failure and the absence is nearly as sensitive as a normal BNP or NT Pro BNP, too. And in the event of systolic heart failure, echo is a great modality to rapidly assess a patient’s pump function; our interpretation is consistent with the formal result obtained by cardiologists [2].

Caution must nevertheless be maintained when evaluating these results. The LRs found in these studies were calculated independently of other findings and in reality, the emergency physician takes multiple factors from the history, physical exam, and other diagnostic modalities, to ultimately come to a definitive diagnosis. Essentially, the short answer is that no single test should be taken as definitive in diagnosis of AHF (or any diagnosis for that matter) and the emergency physician should follow a bayesian approach using pre- and post- test probabilities from their fund of knowledge to rule in and rule out cannot miss diagnoses. Lastly, with regards to this study, physicians should be wary about interpreting these results in the context of renal failure primarily but also superimposed pneumonia or underlying concern for pulmonary embolism as these patients were excluded in a number of papers included in this meta-analysis.

The Bottom Line

Bedside ultrasound to evaluate for the presence or absence of pulmonary edema should be an integral part of the emergency physicians approach to evaluating patients to the emergency department with undifferentiated dyspnea.

Authors

This post was written by Matt Correia, MD PGY-2 at UCSD. It was edited by Michael Macias, MD.

References

1. Martindale JL, e. (2017). Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 14 August 2017, from https://www.ncbi.nlm.nih.gov/pubmed/26910112
2. Moore CL, e. (2017). Determination of left ventricular function by emergency physician echocardiography of hypotensive patients. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 14 August 2017, from https://www.ncbi.nlm.nih.gov/pubmed/11874773

July 22, 2017July 22, 2020

Case # 2: A Needle In the Haystack

A 40 year old male presented with 3 days of progressive dyspnea on exertion. He notes he was in a normal state of health prior to this and played basketball daily without issue but now he can no longer walk across the room without becoming winded. He has no chest pain, a normal chest x-ray and an ECG demonstrating sinus tachycardia

Vitals: HR 109 BP 110/72 RR 22 O2 96

Answer and Learning Point

Answer

There is evidence of severe aortic regurgitation and aortic root dilation (~6 cm) on this parasternal long axis view. In a patient without any previous cardiac history with new aortic regurgitation this is concerning for acute aortic dissection. Cardiac surgery was consulted immediately and the patient was taken straight to CT scan for confirmation of type A aortic dissection. The patient was in the OR within 1 hour and had an excellent outcome.

Learning Point

Aortic dissection is quite uncommon (~5-30 per 1 million people per year) and is often seen in patients with chronic uncontrolled hypertension or other diseases such as bicuspid aortic valve, Marfan Syndrome or Ehlers-Danlos Syndrome. Unfortunately all the "classic" indicators of dissection are actually not that common [1]. Traditionally we are taught that patients with acute aortic dissection will arrive hypertensive, while in actuality up to 1 in 4 patients with Stanford Type A dissection will have a presenting systolic blood pressure below 100 mmHg. Additionally, it is taught that a dissection presents as a “ripping or tearing” pain going to the back. Looking at the data, while over 90% of patients felt that it was the worst pain they had ever experienced, only 50% of subjects described their pain as ripping or tearing (62% described pain as sharp), only 35% had any posterior chest pain, and only 85.4% of patients described the onset of their pain as ‘acute.’ [1]

The varied presentation of this disease makes aortic dissection difficult to diagnose, and the clinician should have a high index of suspicion for this life-threatening disease process. This is where ultrasound comes in. Anyone who has a concerning chest pain story, pain above and below the diaphragm, chest pain + a neurological symptom, or signs and symptoms of acute heart failure without any previous cardiac history, should have a bedside ultrasound performed. While ultrasound cannot rule out aortic dissection, it can rapidly identify complications of dissection and expedite care in these patients whom time is of the essence.

The Approach

Perform standard abdominal aorta ultrasound evaluating for aneurysm or intimal flap. Be sure to evaluate from proximal aorta, in the epigastric region, distally to the iliac vessels. A normal aorta caliber is < 3 cm.

Obtain a parasternal long axis view:

Measure aortic root, this should be less than 4 cm. There are varying opinions on where the best place to take this measurement is, I suggest measuring the largest area you see as it is better to be on the conservative side.
Apply color doppler to evaluate for aortic regurgitation.
Assess global cardiac function. This is useful to see if a patient is compensated or decompensated as well as assist with fluid/pressor management if needed.
Evaluate for pericardial effusion. If there is evidence of effusion and concern for Type A aortic dissection, this suggests that there is communication with pericardial sac.
Evaluate descending thoracic aorta for intimal flap

References

Hagan PG, Nienaber CA, Isselbacher EM, et al. The International Registry of Acute Aortic Dissection (IRAD): New Insights Into an Old Disease. JAMA. 2000;283(7):897-903. doi:10.1001/jama.283.7.897.
Taylor RA, e. (2017). Point-of-care focused cardiac ultrasound for the assessment of thoracic aortic dimensions, dilation, and aneurysmal disease. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 22 July 2017, from https://www.ncbi.nlm.nih.gov/pubmed/?term=22288871
C, K. (2017). Emergency department diagnosis of aortic dissection by bedside transabdominal ultrasound. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 22 July 2017, from https://www.ncbi.nlm.nih.gov/pubmed/19549013
Lang R, Bierig M, Devereux R, et al. Recommendations for Chamber Quantification: A Report from the American Society of Echocardiography’s Guidelines and Standards Committee and the Chamber Quantification Writing Group, Developed in Conjunction with the European Association of Echocardiography, a Branch of the European Society of Cardiology. J Am Soc Echocardiogr 2005; 18: 1440-63.
Rubano E, e. (2017). Systematic review: emergency department bedside ultrasonography for diagnosing suspected abdominal aortic aneurysm. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 22 July 2017, from https://www.ncbi.nlm.nih.gov/pubmed/?term=23406071

July 8, 2017July 22, 2020

Case # 1: The Acutely Winded Traveler

A 65 year old female presents with shortness of breath after a return flight from the Gold Coast of Australia to the United States.

Vitals: HR 107 BP 110/80 RR 22 O2 95

Answer and Learning Point

Answer

There is right ventricular dysfunction demonstrated as septal bowing appreciated on this parasternal short axis view. This is concerning for a pulmonary embolism in the setting of the provided clinical context.

Learning Point

Echocardiography can be a useful adjunct to laboratory markers (i.e. BNP and troponin) and CTA for evaluation of right heart strain in normotensive patients presenting with concern for pulmonary embolism. While there is building evidence that many patients presenting with pulmonary embolism are safe for discharge [1] , those patients that have evidence of right ventricular dysfunction are at higher risk for morbidity and mortality and may also be candidates for more advanced therapies, other than simple anticoagulation, such as catheter directed thrombolysis. The most up-to-date evidence supports that emergency physicians can accurately perform echocardiography at the bedside to risk stratify patients presenting with concern for pulmonary embolism. In a recent study by Weekes et al, emergency physicians (EP) performed goal directed echocardiography to assess for right ventricular dysfunction. If any of the following criteria below were present, a patient was considered positive by goal directed echocardiography for right ventricular dysfunction:

This study found the EP goal-directed echocardiography sensitivity and specificity for right ventricular dysfunction to be 100% (CI 87% to 100%) and 99% (95% CI 94% to 100%), respectively [2]. Our patient ended up having a saddle embolus and underwent catheter directed thrombolysis and did well.

References

Aujesky D, e. (2017). Outpatient versus inpatient treatment for patients with acute pulmonary embolism: an international, open-label, randomised, non-inferiority trial. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 8 July 2017, from https://www.ncbi.nlm.nih.gov/pubmed/21703676
Weekes AJ, e. (2017). Diagnostic Accuracy of Right Ventricular Dysfunction Markers in Normotensive Emergency Department Patients With Acute Pulmonary Embolism. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 8 July 2017, from https://www.ncbi.nlm.nih.gov/pubmed/?term=26973178