MEdIC Series | The Case of the Debriefing Debacle

Welcome back again this week to the Medical Education in Cases series.  Last month we had a record breaking number of people join us for the case discussion, and we hope you will come back and share your thoughts with this one.

This month’s case centers upon Dr. Berner and his student Melanie as they both go through a Cardiac Arrest case. Consider their story and think about how you might approach this case.

MEdIC Series: The Concept

Inspired by the Harvard Business Review Cases and initially led by Dr. Teresa Chan (@TChanMD) and Dr. Brent Thoma (@Brent_Thoma), the Medical Education In Cases (MEdIC) series puts difficult medical education cases under a microscope. On the fourth Friday of the month, we pose a challenging hypothetical dilemma, moderate a discussion on potential approaches, and recruit medical education experts to provide “Gold Standard” responses. Cases and responses are be made available for download in PDF format – feel free to use them! If you’re a medical educator with a pedagogical problem, we want to get you a MEdIC. Send us your most difficult dilemmas (guidelines) and help the rest of us bring our teaching to the next level.

The Case of the Debriefing Debacle

by Dr. Joanna Bostwick

“Excuse me Dr. Berner. One of the nurses came to ask me if we were aware that there is a 20 year old guy in the Resuscitation Room with a heart rate of 200,” said Melanie nervously, a third year medical student who had just started her Emergency Medicine (EM) rotation.

“What? I didn’t hear about that. Let’s go over right away.”

Dr. Berner sprinted ahead as Melanie grabbed her stethoscope. As Dr. Berner entered the Resus Bay he saw a young slender male who did not appear well with vomitus running down his cheek. He looked sonorous and diaphoretic and the monitor showed a heart rate now of 220 bpm. Two nurses were hard at work attempting to establish an IV and draw bloodwork.

“Can anyone tell me about this patient?” Dr. Berner demanded.

“He was found slumped over at a house party tonight. The paramedics think he took a cocktail of drugs and alcohol,” said one of the senior nurses while she primed an IV with normal saline.

Dr. Berner turned to Melanie, “Have you ever intubated before?”

“Ummmm… A few times?” Melanie stuttered, she had intubated a couple of times in the OR but never in the ER. “But I’m not even sure what’s going on here.”

“We can talk more about what’s going on in a moment, first we need to secure the patient’s airway.”

“The O2 sats are starting to drop and I can’t wake him up,” said a nurse anxiously.

“Ok team, let’s give the naloxone and get set up to intubate.”

“The naloxone was given per protocol by EMS with no effect earlier,” stated the charge nurse.

“Alright then, I’m going to intubate right now.” Let’s get the crash cart at the bedside and page RT stat.” Dr. Berner turned to Melanie, “I will have you watch this one and you can attempt the next intubation.”

The patient was intubated successfully and Dr. Berner sighed with relief. With the patient’s airway secure, his oxygenation improved. He now turned to Melanie to ask about toxins that could cause tachycardia when suddenly the monitor started to beep as Dr. Berner looked in horror to see VFib.

“Melanie start chest compressions,” ordered Dr. Berner, “Betty, can you give 1 mg of epi? Also, Sarah can you go get Dr. Takeda and his residents over in the Quick Care area?”

Melanie had never done CPR before in real life and shuddered in horror as she felt ribs breaking beneath her hands.

Her head was spinning. What had just happened? She was beginning to feel her arms fatiguing and didn’t know how she could keep this up.

There was a fury of people who suddenly appeared to help at the bedside.

“Ok stop CPR let’s check the rhythm and pulse,” said Dr.Berner.

“Asystole,” said several in unison.

“Resume CPR,” Dr Berner said and then turned to Melanie, “you can switch off with Joe. He’s right behind you, ready to take over CPR.”

“Dr. Berner the family has arrived they would like to find out what’s happening and want to see their son,” said the social worker quietly from the doorway. I have tried to prepare them for what they are about to see.” Dr. Berner nodded his assent, and the social worker disappeared momentarily. A few minutes later, she returned with a middle-aged couple, both clinging to her for support.

“Another round of epi please, Betty?”

“How long has the code been going on?” asked Dr. Takeda as he arrived. He and Dr. Berner turned to each other to discuss the proceedings on the code, just out of Melanie’s earshot. Dr. Takeda then went over to talk to the parents of the patient, talking to them somberly for several moments.

A few moments later, the couple looked to him and said: “Please stop.”

Dr. Takeda then nodded at Joe, who had the bedside ultrasound set up, and ready to use at the next rhythm check.

“Rhythm and pulse check please,” ordered Dr. Takeda.

“No pulse… Asystole…”

“Bedside echo shows no cardiac activity.”

“Let’s call the code,” sighed Dr. Berner. “Time of death…”

There was a large wail as the patient’s mother fell to the ground. Melanie tried to hold back her own tears.

For the next few minutes, Melanie felt like she was walking through a daze. Had that really just happened? She felt like it had just been a few minutes since she had seen him arrive with the paramedics! He had groaned when she tried to do a sternal rub… He had been alive. What had happened? Maybe her compressions weren’t forceful enough? What if it was her fault?

 

Key Questions

  1. How do you debrief this case with Melanie?
  1. How do you address her fears that she did something wrong?
  1. What is a general approach to debriefing a medical student after a bad outcome in a young patient?
  1. What is the role of the family’s presence during a resuscitation?

Weekly Wrap Up

As always, we will post the expert responses and a curated commentary derived from the community responses one week after the case was published. This time the two experts are:

  • Hans Rosenberg (@hrosenberg33) who is an emergency physician at The Ottawa Hospital and Assistant Professor at the University of Ottawa. IT Director and Social Media keener.
  • Tessa Davis (@TessaRDavis) is a pediatric emergency physician from Sydney, Australia. She is also the co-creator of the Don’t Forget the Bubbles blog.

On October 31, 2014, we will post the Expert Responses and Curated Community Commentary for the Case of the Debriefing Debacle. After that date, you may continue to comment below, but your commentary will no longer be integrated into the curated commentary which is released on October 31, 2014. That said, we’d love to hear from you, so please comment below!

All characters in this case are fictitious. Any resemblance to real persons, living or dead, is purely coincidental. Also, as always, we will generate a curated community commentary based on your participation below and on Twitter. We will try to attribute names, but if you choose to comment anonymously, you will be referred to as your pseudonym in our writing.

Author information

Teresa Chan, MD

ALiEM Associate Editor

Emergency Physician, Hamilton

Assistant Professor, McMaster University

Ontario, Canada
+ Teresa Chan

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Diagnose on Sight: 6 year old with elbow pain

elbowCase: A previously healthy 6 year old male presents with left elbow pain after wrestling with a friend. What is the diagnosis? Click on image for a larger view.


 

 

Poll

 

Answer (Click for explanation)

Type II Supracondylar fracture of the elbow

 

Explanation

More than half of all pediatric elbow fractures are supracondylar, because this is the weakest part of the elbow joint. They are most commonly caused by a fall on outstretched hand [1].

In this case, the anterior humeral line (red) does not intersect the middle third of the capitellum, suggesting a fracture. The arrow points to a disruption of the anterior cortex.

elbow with arrows

Choice of treatment is guided by the Gartland classification. Most orthopedists recommend conservative management for non or minimally displaced fractures, while displaced fractures are treated with operative fixation [2].

Gartland classification [2]

 

Special attention must be paid to a careful neurovascular exam to evaluate for compartment syndrome. A delay in diagnosis can lead to the devastating complication of Volkmann’s ischemic contracture, which results in severe muscle fibrosis and neuropathy [3].

 

Master Clinician Bedside Pearls

ChrisDoty-298x298Christopher I. Doty, MD
Program Director & Vice Chair for Education
Associate Professor of Emergency Medicine
University of Kentucky-Chandler Medical Center

 

 

References

  1. Chasm RM, Swencki SA. Pediatric orthopedic emergencies. Emerg Med Clin North Am. 2010 Nov;28(4):907-26. PMID: 20971397.
  2. Ladenhauf HN, Schaffert M, Bauer J. The displaced supracondylar humerus fracture: indications for surgery and surgical options: a 2014 update. Curr Opin Pediatr. 2014 Feb;26(1):64-9. PMID: 24378825.
  3. Omid R, Choi PD, Skaggs DL. Supracondylar humeral fractures in children. J Bone Joint Surg Am. 2008 May;90(5):1121-32. PMID: 18451407.

Author information

Jeff Riddell, MD

Jeff Riddell, MD

Chief Resident

UCSF-Fresno Emergency Medicine Residency

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Antibiotics, Myasthenia Gravis, and Risk of Weakness

antibioticsA 71 year old female presents to the ED with lethargy, fever (39.5 C), and tachypnea (RR 28 rpm). She has a long-standing history of myasthenia gravis (MG) for which she receives periodic IVIG infusions. She is accompanied by her son, who informs you that she had a recent 10-day hospital stay for weakness. A CXR reveals an infiltrate in the left lower lobe.

The decision is made to initiate antimicrobial therapy for presumed healthcare-associated pneumonia. But, which antibiotics are safe to use in a patient with severe MG?

 

The Problem: Antibiotics and Myasthenia Gravis

Antibiotics are one of several classes of medication that can impair neuromuscular transmission and may increase weakness in patients with underlying junctional disorders [1]. Numerous case reports link antibiotic administration to causing neuromuscular weakness, though this occurs even in normal patients.

Risk of Increased Weakness [1, 2]

Based on reported literature, these antibiotics seem to have at least some likelihood of exacerbating underlying MG. The risk of increased weakness is reported.

Drug Class
Specific Antibiotics *
Risk of Increased Weakness **
AminoglycosidesNeomycin, gentamicin, amikacin, streptomycin, tobramycinHigh
Fluoroquinolones ***Ciprofloxacin, ofloxacin, norfloxacinHigh
KetolidesTelithromycinHigh
MacrolidesAzithromycin, erythromycinModerate
PolymyxinsColistimethate, polymyxin BModerate
PenicillinsAmpicillinLow
OtherNitrofurantoin, vancomycin, clindamycin, sulfonamidesLow

* Not an all-inclusive list, but includes most that have been reported

** Risk is based on estimated prevalence and severity of effect

*** Note that the fluoroquinolones have a black-box warning against using them in patients with MG.

Take Home Points

The 2012 Medications and Myasthenia Gravis (A Reference for Health Care Professionals) says it best:

  • Nearly every antibiotic ever studied has demonstrated some deleterious effect or has been the subject of a clinical report suggesting exacerbation of MG.
  • If a patient requires antibiotic treatment for an infection, then the appropriate drugs should be utilized.
  • When managing patients with neuromuscular junctional disease, it simply behooves the clinician to remain alert to the potential for clinically significant adverse effects, especially if the patient becomes weaker in the setting of antibiotic use.

References

  1. Mehrizi M, et al. Medications and Myasthenia Gravis (A Reference for Health Care Professionals). Prepared for the Myasthenia Gravis Foundation of America. August 2012. [free PDF]
  2. Jones SC, et al. Fluoroquinolone-associated myasthenia gravis exacerbation: evaluation of postmarketing reports from the US FDA adverse event reporting system and a literature review. Drug Saf. 2011;34(10):839-47. PMID 21879778

 

Edited by: Scott Kobner, ALiEM-EMRA fellow.

Author information

Bryan D. Hayes, PharmD, FAACT

Bryan D. Hayes, PharmD, FAACT

ALiEM Associate Editor

Clinical Assistant Professor, University of Maryland (UM)

Clinical Pharmacy Specialist, EM and Toxicology

The post Antibiotics, Myasthenia Gravis, and Risk of Weakness appeared first on ALiEM.

I am Dr. Ryan Radecki, author of EM Literature of Note: How I Work Smarter

How I Work Smarter LogoIn a previous How I Work Smarter post by Dr. Ken Milne, he called out Dr. Ryan Radecki, who is the outspoken and prolific author of EM Literature of Note and a premiere mythbuster in EM, specifically around thrombolytics in stroke. For those of us in the blogging world, not everyone knows that he lives a dual academic life working on medical informatics and information design. He is, in fact, funded through an NIH grant from the Agency of Healthcare Research and Quality for a training program in patient safety. Ryan shares his tips for working smarter.

  • radecki_headshotName: Ryan Radecki, MD, MS
  • Location: Houston, TX
  • Current job: Assistant Professor of Emergency Medicine at The University of Texas Medical School at Houston
  • One word that best describes how you work: Everywhere
  • Current mobile device: iPhone 5
  • Current computer: 15” Macbook Pro

What’s your office workspace setup like?

What’s an office? I’m lucky enough to have such flexibility in my position I’m confined only to wherever my creative needs take me on the day. I’ve got a quiet space set aside at my home as a “home office”, which is where podcasting and administrative work gets done. But my main office – is every coffeehouse in town, depending on the rest of the day’s logistics. Today, I’m at Boomtown Coffee – fueled by iced toddy mocha.

Radecki home office

Radecki Coffee Shop

 

What’s your best time-saving tip in the office or home?

There are few time-wasting endeavors I dislike more than time spent commuting. I have always specifically tried to live in locations with the shortest possible commute. I also ride my bike to work, when possible – I arrive far more awake, and with the added bonus of having accomplished part of my exercise for the day.

What’s your best time-saving tip regarding email management?

Run e-mail like running the department – disposition-focused. Delete as much as possible, respond immediately by phone when practical, and otherwise “run the list” of recent e-mails a couple times a day when the opportunity arises.

What’s your best time-saving tip in the ED?

Document as much as possible up front, immediately after the patient encounter. I don’t document during the encounter. I’d rather have an effective, efficient patient encounter and charting session in series, rather than do both tasks simultaneously, but poorly. Then, left to the end of shift, documentation quality both degrades and requires longer to create.

ED charting: Macros or no macros?

Macros. Ideally, lots of macros – focused on the most common complaints and recurrent medical decision-making documentation.

What’s the best advice you’ve ever received about work, life, or being efficient?

Everyone mentions the ability to say “no” as critical – and I agree. While there’s always some modicum of suffering required, the fewer extraneous responsibilities outside your areas of passion, the better. More time available to do your best work? Win.

Is there anything else you’d like to add that might be interesting to readers?

I strongly feel it is our ethical responsibility to patients and society at large to order precisely the indicated tests and therapies – no more, no less. Being judicious with limited resources is an incredibly difficult challenge – but the alternative is simply lazy, thoughtless, wasteful medicine. I also find involving patients in decisions at every step of the process, with explanations of goals of care, diagnostic strategies, and estimates of costs – results in interesting and revealing conversations of substantial value in directing care. Many patients opt for less complex diagnostic evaluation, and more focus on symptom resolution – and thus my rates of use of advanced imaging and hospitalization are much lower than average, without apparent degradation in safety at discharge. This is, in many ways, the future of medicine – as the writing is already on the wall regarding cultural shifts to decreasing unnecessary testing and resource utilization.

Who would you love for us to track down to answer these same questions?

  • Megan Ranney
  • Nick Genes
  • Jeremiah Schuur

Author information

Michelle Lin, MD

ALiEM Editor-in-Chief

Editorial Board Member, Annals of Emergency Medicine

UCSF Academy Endowed Chair for EM Education

UCSF Associate Professor of Emergency Medicine

San Francisco General Hospital

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Valproic Acid-Induced Hyperammonemic Encephalopathy

Valproic AcidValproic acid is used for a variety of clinical indications including seizures, migraine prophylaxis and treatment, and bipolar disorder. A metabolite of valproic acid, thought to be propionic acid, has the ability to increase ammonia levels by inhibiting a step in the hepatic urea cycle, which may lead to valproic acid-induced hyperammonemic encephalopathy. As a result, patients treated with valproic acid presenting with signs and symptoms of acute mental status changes, increased seizure frequency, and/or gastrointestinal symptoms should be evaluated for elevated ammonia concentrations.

At Risk Patients [1,2]

Hyperammonemic encephalopathy may occur at any time during therapy with valproic acid. There is NO established relationship between the timing of initiation of valproic acid and symptom onset. In adult patients, age and gender have also been shown to have NO association with the occurrence of  hyperammonemic encephalopathy. Symptoms may occur at pharmacologically therapeutic levels.

While you should have suspicion for this pathology in any patient presenting with altered mental status on valproic acid, the following factors may place the patient at an increased risk for this complication:

  • Anticonvulsant polytherapy and medication interactions
    • Medications such as topiramate, phenytoin, carbamazepine, and phenobarbital have been associated with increased ammonia levels when used in conjunction with valproic acid
  • Renal failure
  • Hepatic failure
  • Carnitine deficiency: Carnitine assists with the elimination of valproic acid and minimizes the formation of harmful valproic acid metabolites.
    • Catabolic states such as trauma or fasting
    • Strict vegetarian diet or malnourishment
    • Long term and/or high dose valproic acid therapy or valproic acid overdose
    • Rare genetic conditions

Treatment: Levocarnitine [1-4]

Levocarnitine is the active isomer of carnitine, an essential cofactor in fatty acid metabolism. In patients with ample supply of carnitine, the majority of valproic acid is metabolized to non-toxic metabolites. In the absence of carnitine, valproic acid metabolism is shifted to an alternate pathway and can result in toxic metabolites, one of which will inhibit the urea cycle resulting in ammonia accumulation. While there are no large, randomized, controlled trials of levocarnitine treatment, numerous case reports and review articles have suggested a benefit with levocarnitine treatment in patients experiencing valproic acid induced hyperammonemic encephalopathy.

One review recommended the following regimen for patients with valproic acid overdose: 100 mg/kg IV loading dose followed by 50 mg/kg (maximum of 3 grams) IV every 8 hours until the ammonia levels are decreasing and the patient is improving [3]. The same loading dosing with lower subsequent doses (50 mg/kg/day) has also been suggested for patients who have developed hyperammonemic encephalopathy with either routine valproic acid therapy or overdose [4].

Take Home Points

  • The usage of valproic acid is increasing, as it is being utilized for a wider variety of indications.
  • Ammonia levels may become elevated in patients treated with valproic acid.
  • Hyperammonemic encephalopathy is possible at any time during treatment and at any valproic acid concentration (including therapeutic levels).
  • Symptoms may include an acute onset of nausea and vomiting, lethargy, cognitive slowing, seizures and decreased levels of consciousness.
  • Treatment for hyperammonemic encephalopathy from valproic acid includes valproic acid cessation +/-  levocarnitine treatment.

References

  1. Chopra A, et al. Valproate-induced hyperammonemic encephalopathy: an update on risk factors, clinical correlates and management. Gen Hosp Psychiatry 2012;34 (3):290-8. PMID 22305367
  2. Lheurex PE, et al. Carnitine in the treatment of valproic acid-induced toxicity. Clin Toxicol 2009;47(2):101-11. PMID 19280426
  3. Perrott J, et al. L-carnitine for acute valproic acid overdose: a systematic review of published cases. Ann Pharmacother 2010;44(7-8):1287-93. PMID 20587742
  4. Mock CM, et al. Levocarnitine for valproic-acid-induced hyperammonemic encephalopathy. Am J Health Syst Pharm 2012;69(1):35-9. PMID 22180549

Associate Editor: Bryan D. Hayes, PharmD, FAACT (@PharmERToxGuy)
ALiEM-Cord Fellow and Editor: Sam Shaikh, DO (@SynthShaikh)

Author information

Jill Logan, PharmD BCPS

Jill Logan, PharmD BCPS

Clinical Pharmacist

Baltimore Washington Medical Center

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Blunt Chest Trauma: Validation of the NEXUS Chest Rule

Rib fx Chest CTWe commonly see patients who have some form of blunt chest trauma. This is the result of motor vehicle collisions, falls, and a myriad of other traumatic events. The decision to perform thoracic imaging can be difficult. Chest xray (CXR) and/or chest CT? In fact, studies have shown that emergency and trauma physicians often disagree 28-40.9% of the time about which patients require a chest CT following blunt trauma [1, 2].

Background

A recent meta-analysis [3] concluded that patients undergoing whole-body CT (head, neck, chest, abdomen, and pelvis) had a lower overall mortality than trauma patients undergoing selective CT. It is important to note that the results were based on mostly retrospective studies. Also, indiscriminate CTs in low-risk patients have the potential to cause harm from radiation exposure. A 45-year-old who undergoes a whole-body CT has a lifetime attributable risk of cancer mortality of 0.08% [4]. This means that the number needed to harm from a single trauma whole-body CT is approximately 1,250.

The lack of consensus in determining the need for a whole-body CT demonstrates the need for a decision instrument. To address the need for at least chest imaging, Rodriguez et al. have done several studies to develop the NEXUS Chest rule to aid in the decision making process.

The 7 clinical variables in the NEXUS Chest decision instrument are:

  1. Age > 60 years
  2. Rapid deceleration mechanism (fall > 20 ft or MVC > 40 mph)
  3. Chest pain
  4. Intoxication
  5. Abnormal mental status
  6. Distracting painful injury
  7. Tenderness to chest wall palpation

The NEXUS Chest rule was derived in two separate studies [5, 6]. Most recently in 2013, Rodriguez et al. published a validation study of this NEXUS Chest rule [7]. This is what will be reviewed below.

Study

NEXUS Chest Validation of a Decision Instrument for Selective Chest Imaging in Blunt Trauma [7]

Study Design

  • Prospective, observational, diagnostic decision instrument study
  • 9 U.S. Level 1 trauma centers
  • Patients enrolled during 7 am -11 pm via systematic sampling method
  • Inclusion criteria
    1. > 14 years old
    2. Blunt trauma within 24 hours of Emergency department (ED) presentation
    3. Underwent chest imaging (CXR or chest CT) in the ED as part of their evaluation

Outcome Data

The presence or absence of Thoracic Injury seen on Chest Imaging (TICI) was determined on CXRs and Chest CTs, as interpreted by board certified radiologists. Prior to the derivation studies, an expert panel of emergency and trauma physicians defined TICI as any of the following:

  • Pneumothorax
  • Hemothorax
  • Aortic or great vessel injury
  • ≥2 rib fractures
  • Ruptured diaphragm
  • Sternal fracture
  • Pulmonary contusion or laceration

Pericardial tamponade and cardiac contusion were excluded. As part of the NEXUS Chest validation study, an expert panel of 10 physicians classified injuries according to associated clinical interventions.

Results

  • 9,905 patients enrolled prospectively
  • Mean age: 46 years
  • Imaging practices:
    • 43.1% patients had a CXR
    • 42.0% patients had a CXR and chest CT
    • 6.7% patients had a CXR and abdominal CT
    • 5.5% patients had multiple CXRs without CT
    • 2.6% patients had a chest CT without CXR
  • TICI was seen in 1,478 (14.9%) of patients:
    • 363/1478 (24.6%) had MAJOR clinical significance
    • 1079/1478 (73.0%) had MINOR clinical significance
    • 36/1478 (2.4%) had NO clinical significance
  • Operating characteristics of NEXUS Chest Decision Instrument for all TICI:
    • Sensitivity 98.8% (95% CI, 98.1% – 99.3%)
    • Specificity 13.3% (95% CI, 12.6%-14.1%)
    • Negative Predictive Value 98.5% (95% CI, 97.6-99.1%)
    • Positive Predictive Value 16.7% (95% CI, 15.9-17.5%)
    • Negative Likelihood Ratio 0.09 (95% CI, 0.05-0.14)
  • Decision instrument missed 17 TICI (false-negatives).
    • 1/17 of those TICI was clinically significant (pneumothorax which required a chest tube).
    • Therefore, the negative likelihood ratio for TICI with MAJOR clinical significance is 0.02 (95% CI, 0-0.16).

Conclusions and Future Directions

  1. Patients who do not have any of the 7 NEXUS Chest rule clinical variables (score = 0) do not need chest imaging.
  2. This decision instrument is nonspecific and, therefore, would likely not lead to a dramatic decrease in imaging. Future research should focus on delineating the need for a chest CT versus only a CXR. The major concern with only a CXR is the fear of missing aortic and major vessel injuries, which are identifiable on chest CT. However, in the NEXUS study reviewed above, only 15/9905 (0.15%) patients had injuries to the aorta or major vessels. This extremely low rate of aortic injury may NOT justify liberal use of chest CT in low-risk stable patients. Instead, a CXR may be a reasonable screening tool for traumatic aortic injury (TAI), as supported by a decision instrument derived in 2006 [8]. In that study, the following CXR criteria of (1) a displaced left paraspinous line, (2) an abnormal aortic knob, and (3) a widened mediastinum comprised a decision instrument with a negative likelihood ratio of 0.18.
  3. Thoracic ultrasound (US) should be considered in developing future decision rules. In this study, pneumothorax and pulmonary contusion comprised 10/17 of the TICI missed by the decision rule. This included the one missed major injury. A 2010 systematic review [9] concluded that thoracic US has a higher sensitivity (86-98%) versus a supine AP CXR (28-75%) in the setting of blunt trauma. Another systemic review found thoracic US to have a sensitivity of 90.9% when compared to CT [10]. In the same study supine CXR was only 50.2% sensitive. Additionally, thoracic US has good diagnostic accuracy for lung contusion [11]. Ultimately, US may pick up small contusions and pneumothoraces while obviating the need for CT in most stable patients.

Suggested algorithm for thoracic imaging in trauma

  • NEXUS Chest score = 0
    • No thoracic imaging required
  • NEXUS Chest score ≥ 1
    • In well-appearing patient with no evidence of multiorgan injury –> CXR only without chest CT
    • In ill-appearing patients and/or those who will receive workup for other serious injury –> chest CT

References

  1. Tillou A, Gupta M. Baraff LJ, Schriger DL, Hoffman JR, Hiatt JR, Cryer HM. Is the use of pan-computed tomography for blunt trauma justified? A prospective evaluation. J Trauma. 2009 Oct;67(4):779-87. PMID: 19820586.
  2. Gupta M, Schriger DL, Hiatt JR, Cryer HG, Tillou A, Hoffman JR, Baraff LJ. Selective use of computed tomography compared with routine whole body imaging in patients with blunt trauma. Ann Emerg Med. 2011 Nov;58(5):407-16.e15. PMID: 21890237
  3. Caputo ND, Stahmer C, Lim G, Shah K. Whole-body computed tomographic scanning leads to better survival as opposed to selective scanning in trauma patients: A systematic review and meta-analysis. J Trauma Acute Care Surg. 2014 Oct;77(4):534-9. PMID: 25250591
  4. Brenner DJ, Elliston CD. Estimated radiation risks associated with full-body CT screening. Radiology. 2004 Sep;232(3):735-8. PMID: 15273333
  5. Rodriguez RM, Hendey GW, Marek G, Dery RA, Bjoring A. A pilot study to derive clinical variables for selective chest radiography in blunt trauma patients. Ann Emerg Med. 2006 May;47(5):415-8. PMID 16631976.
  6. Rodriguez RM, Hendey GW, Mower W, Kea B, Fortman J, Merchant G, Hoffman JR. Derivation of a decision instrument for selective chest radiography in blunt trauma. J Trauma. 2011 Sep;7(3):549-53. PMID: 21045745
  7. NEXUS chest: validation of a decision instrument for selective chest imaging in blunt trauma. Rodriguez RM, Anglin D, Langdorf MI, Baumann BM, Hendey GW, Bradley RN, Medak AJ, Raja AS, Juhn P, Fortman J, Mulkerin W, Mower WR. JAMA Surg. 2013 Oct;148(10):940-6. PMID: 23925583. Free article PDF
  8. Ungar TC, Wolf SJ, Haukoos JS, Dyer DS, Moore EE. Derivation of a clinical decision rule to exclude thoracic aortic imaging in patients with blunt chest trauma after motor vehicle collisions. J Trauma. 2006. Nov;61(5):1150-5. PMID: 17099521
  9. Wilkerson RG, Stone MB. Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the identification of pneumothorax after blunt trauma. Acad Emerg Med. 2010. Jan;17(1):11-7. PMID: 20078434.
  10. Alrajhi K, Woo MY, Vaillancourt C. Test characteristics of ultrasonography for the detection of pneumothorax: a systematic review and meta-analysis. Chest. 2012. Mar;141(3):703-8. PMID: 21868468
  11. Hyacincthe AC, Broux C, Francony G, Genty C, Bouzat P, Jacquot C, Albaladejo P, Ferretti GR, Bosson JL, Payen JF. Diagnostic accuracy of ultrasonography in the acute assessment of common thoracic lesions after trauma. Chest. 2012. May;141(5):1177-83. PMID: 22016490.

 

Expert Peer Review: Dr. Robert Rodriguez (lead author)

October 8, 2014

While the rate of traumatic injuries has remained steady, the use of diagnostic imaging for blunt trauma evaluation (especially head to pelvis CT, or “Pan-Scan”) has increased substantially. Indiscriminate use of imaging leads to higher costs, emergency department time, and perhaps most importantly—increased patient radiation exposure. One important measure to quell this explosion in use of imaging, is the development and use of decision instruments (DIs), such as the NEXUS Cervical Spine rule, to safely guide selective imaging.

Our work is directed at decreasing unnecessary thoracic imaging in blunt trauma evaluation. As Dr. Morley summarizes well, we have derived and validated the NEXUS Chest DI that safely guides selective chest/thoracic imaging. It is true that with its relatively low specificity, NEXUS Chest will be able to rule out intra-thoracic injury and spare imaging in a minority of patients (approximately 13%). Our rationale behind developing this low specificity rule is a product of the need to adhere to the overriding principle of maximizing safety, or sensitivity, of the DI. Our expert trauma panel consisting of emergency medicine physicians and trauma surgeons strongly believed that in order to be widely accepted and implemented, a selective chest trauma imaging DI must have near-perfect ability to detect (and rule out) clinically significant injury. Our rule meets that critically important criterion of safety: The sensitivity and negative predictive value of NEXUS Chest for clinically major injury were 99.7% (95%CI, 98.2%-100.0%) and 99.9% (95%CI, 99.4%-100.0%), respectively [1].

It is important to note that NEXUS Chest (and essentially all other directive rule out injury DIs) only tell clinicians when it is safe to forego imaging—they do not mandate imaging in those patients who happen to have one or more of the 7 criteria. Misuse of DIs in this manner can paradoxically lead to increased imaging. For example, when evaluating a geriatric patient who had a minor fall, the fact that the patient is older than 60 years (one of our criteria) does not mean that you have to get a CXR or other chest imaging. NEXUS Chest should not be applied to all adult blunt trauma patients—it should be used in those patients in whom you were already planning to image.

NEXUS Chest will eliminate the need for chest imaging (mostly CXR) upfront in certain blunt trauma patients but where do we go from there in terms of reducing unnecessary diagnostic imaging of the thorax in blunt trauma? The next goal is to reduce chest CT in blunt trauma. We have demonstrated that although chest CT has much higher sensitivity for diagnosing intra-thoracic injury, its indiscriminate use is associated with very high cost and patient radiation exposure. Chest CT in the blunt trauma patient who has a normal or near-normal CXR may be associated with over $200,000 in charges and 593 millisievert effective radiation dose per major injury identified [2].

We are currently in the final stages of developing a DI for selective chest CT in trauma, which we will incorporate into a comprehensive selective chest imaging algorithm.

  1. Rodriguez RM, Anglin D, Langdorf MI, et al. NEXUS Chest: Validation of a decision instrument for selective chest imaging in blunt trauma. JAMA Surg. 2013 Oct;148(10):940-6. PMID: 23925583.
  2. Rodriguez RM, Baumann BM, Raja AS, et al. Diagnostic yields, charges, and radiation dose of chest imaging in blunt trauma evaluation. Acad Emer Med. 2014;6:644-650. PMID: 25039548
Robert Rodriguez, MD, Professor of Clinical Emergency Medicine, UC San Francisco (UCSF)

 

 

Author information

Eric Morley, MD

Eric Morley, MD

Associate Residency Director

Assistant Professor of Emergency Medicine

SUNY Stony Brook

Associate Chief of EM, Peconic Bay Medical Center

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