CORE Case 2 Workshop Petra Lewis MD Professor of Radiology and OBGYN Geisel School of Medicine at Dartmouth

Learning objectives Distinguish patients who do and do not need a pre-op CXR Describe features affecting how we manage SPNs List ways that we can manage SPNs in patients Contrast radiographic signs of atelectasis and consolidation There is a lot here, may not cover all in one session or be selective

Learning objectives Determine when atelectasis is present and localize it Apply an algorithm to distinguishing the different causes for an opacified hemithorax List the features of a pneumothorax on different views Recognize tension pneumothorax on a radiograph and describe its treatment ** Here is an alternate for the preceding slide that has learning objectives expressed in more active verbs and that allow assessment more directly. Not sure its any better, but some alternate language to give us choices…. Perhaps higher in Bloom’s taxonomy There is a lot here, may not cover all in one session or be selective

What questions/difficulties did you have arising from the case Note down areas that they had problems. If not covered in current session or planned sessions then will come back to at the end

Should this patient get a pre-op CXR? 37 year old man with no cardiorespiratory symptoms currently but a history of asthma pre-op ACL repair In which of these scenarios should a patient have a preop CXR (none using ACR guidelines) A: NO

Should this patient get a pre-op CXR? 70 year old asymptomatic woman pre-op hip replacement In which of these scenarios should a patient have a preop CXR (none using ACR guidelines) A: NO

Should this patient get a pre-op CXR? 45 year old diabetic man with no cardiorespiratory symptoms currently pre-op renal transplant In which of these scenarios should a patient have a preop CXR (none using ACR guidelines) A: NO

Who should get a pre-op CXR? Acute cardiopulmonary findings by history or physical Chronic cardiopulmonary disease in the elderly (>age 70), previous chest radiograph within 6 months NOT available Possibly Chronic cardiopulmonary disease in the elderly (>age 70), previous chest radiograph within 6 months available

Solitary Pulmonary Nodules

What factors might affect whether we see a solitary pulmonary nodule? Size, radiographic quality, place in lung (danger zones, blind areas), density, surrounding parenchyma

Where might we miss a nodule? Get students identify areas of the lung where we might miss nodules

What factors affect how we manage a lung nodule? Patient factors Radiographic factors Patients –risk factors, smoking, age, sex, history malignancy, old films - stabilty Radiographic – size, margins, calcification, presence of other nodules, enhancement

Benign hamartoma versus a lung cancer, compare and contrast

How can we manage an SPN seen on a CXR? Assess Follow up Open discussion, fairly superficial Ignore Assess by CT, Biopsy – CT, open, videoscopic, FDG PET Follow up CT, CXR

Fleischner Society 2017 Guidelines for Management of Incidentally Detected Pulmonary Nodules in Adults They don’t need to know details, just that there are criteria that we use to follow SPNs

Atelectasis

What are the characteristics of atelectasis? A. volume loss, opacity, low lung volumes, usually lack of air bronchograms, may be rapid changes Get them to talk about volume loss, opacity, low lung volumes, usually lack of air bronchograms, may be rapid changes

What are the causes of atelectasis Get them to describe = Mucous plug (surgery, intubation, poor inspiration, supine posture, viral infections), tumors – b9 and malignant, compressive etc

What are the signs of volume loss? Q. What structures move from their normal positions in atelectasis? A. diaphragms, hilar, fissures, trachea, heart etc Get students identify the structures that can move with volume loss – diaphragms, hilar, fissures, trachea, heart etc

Q. What is the abnormality. A Q. What is the abnormality? A. Low lung volumes, and linear water/tissue density shadows in the lung bases. Q. When or in what clinical setting does atelectasis occur? A. post operative, poor inspiration, and any causes of same. Linear or ‘plate like’ atelectasis. What do they see here? When might we see this in patients?

Q. What abnormality is present Q. What abnormality is present? It may be necessary to prompt learners to focus on R paratracheal region on PA to perceive the increased radiodensity and the elevated transverse. Prompt them to compare the overall size of lung shadow (R is smaller). On lateral have learners focus on abnormal increased radiodensity above the heart anteriorly. Q: Why is this not just a right paratracheal mass (vol loss) Q. What lobe? A: RUL Q. What signs of volume loss are present? A: trachea to right, right hilar elevation, diaphragm elevation Q. What are some causes of this pattern of radiographic abnormality? RUL atelectasis. Tell me what they see, how would they describe it? What lobe? Where are the signs of volume loss? What might be the cause in this patient?

RUL atelectasis Prompt learner to recognize: 1. the atelectatic RUL that is collapsed against the mediastinum 2. The shift of the mediastinum toward the right. 3. The asymmetric decrease in volume of the right lung. All these are signs of atelectasis. Now consider WHY did it occur.

RUL atelectasis Another example. This was viral pneumonia in an asthmatic young person (mucus plug) Prompt learners to recognize the elevated upper pleural surface ot the RML in another case of RUL atelectasis. Patterns help.

Pig Bronchus Include if you have time and interest Just for fun – Q: What happens when you intubate a patient with a ‘tracheal or ‘pig’ bronchus (0.1-2% patients)? A: they collapse RUL Q: Why do all vet cxrs and diagrams have the right lung on the right? A: Because they exam animals from their backs

example of a pig bronchus on CT

LLL atelectasis in a sick ICU patient. Q. What is the abnormality? A. Abnormal increased retrocardiac density and lost visibility of descending aortic and left diaphragmatic shadow (silhouette sign). Q. Is it pneumonia or atelectasis? Correct answer is ‘Yes.” but more useful answer is we cannot be sure at the moment. What do they see? Is this pneumonia or atelectasis? Why cant they tell?

Clinical clues can help, but follow up is better able to distinguish, as atelectasis clears more rapidly than a pneumonia. Same patient 24 hrs later, bring out the rapid changes seen in atelectasis Day 1 Day 2

RLL atelectasis and RML consolidation. Q. How will you describe the findings here? Imagine you are on the phone describing the image to your resident. A. “Right heart border and right hemidiaphragm are both invisible, indicating a silhouette sign along those interfaces. These localize disease in the right lung in the RML and RLL.” Q. Where are the signs of volume loss? A. Pulmonary vascularity is sparse in right lung, pulled down by the collapse. (**Learners often blurt out “dextrocardia” when they initially see this image, so it provides opportunity to reinforce teaching to temper initial impressions with facts they gather by a systematic review of the CXR image) **RUL atelectasis**(?)**. Tell me what they see, how would they describe it? What lobe or lobes? Where are the signs of volume loss??

RLL atect and RML consolidation

RML atelectasis. Q. What are the findings? A. Markedly small and abnormally dense RML. Q. How is this different from the RML pneumonia we saw earlier? A. We see volume loss in this case, reflecting atelectasis, unlike the pneumonia case. What do they see?

LUL atelectasis. Q. Why is this different than RUL atelectasis? A. The LLL extends superiorly and medially in LUL collapse, with expansion displacing the LUL toward the anterior chest wall. Q. Why can we still see vascular markings on the left on the PA? A. We see the vascular markings in the LLL, which are still outlined by air through the shadow of the LUL that is collapsed. Q. What is a frequent cause of LUL Collapse? A. Lung cancer Get them to describe the findings, Why is this different than RUL atelectasis? Why can we still see vascular markings on the left on the PA? Talk about cause almost always being Ca

LUL atelectasis Here is the CT in that case. Q. Can you point out the collapsed LUL? A. Learner points it out (iPad, pointer, finger etc) Q. Is this simple atelectasis? A. No. Q. Is this due to a mucus plug? A. No. Make sure they recognize the large hilar mass lesion causing the LUL atelectasis.

Total lung atelectasis What would you see if the lung were totally collapsed?

Total left lung collapse

DDx of unilateral hemithorax opacification Causes Volume ↑ ➔ ↓ Get them to list the ddx of hemithorax opacification, then bring out key concept of volume loss and how it differs between the causes.

Left lung pneumonectomy Q. Why do we only see one hemidiaphragm on lateral? A. The other is obscured (silhouetted out) by pleural fluid or other tissue after pneumonectomy on the left. Q. Why do we see inc retrosternal air? A. Herniation of the right lung across midline Q. How do we know this patient is s/psurgery not just atelectasis? A. There is a posterior rib missing.

Day 1 s/p pneumonectomy to discuss how the cavity fills in

Huge right pleural effusion. Get them to pick out the mass effect. Malignant pleural effusion

Pneumothorax Note, supine PTX is covered in Case 3/Workshop 3

What are the signs of a pneumothorax Get them to talk about signs of ptx – pleural lines, how thick they are, where do you see them?, absent lung markings, collapsed lung etc

What can we do to see pneumothoraces better? Views that may help, Lighter (less exposed) film, change parameters on PACS, CLAHE filter, mag up apices, Decubitus (abn side up), Expiratory views CT

Right Ptx.

Exp view of patient post biopsy with a hydropneumo ptx

Skin folds. Is there a ptx? A. No. Q. Why not? How does this look different? A. Line versus edge. (line thickness, can’t follow, lung markings over apex etc.) Mention scapula line on other side.

So you find a pneumothorax… What is your next question ALWAYS? Is there any sign of tension?

What are the signs of tension? Clinical Radiographic Clinical – dec BP, tachcardia, venous distension, hypoxia, pulsus paradox etc CXR: shift mediastinum, depressed diaphragms, +/-major lung collapse, small heart (esp on CT compression of RA/RV). Discuss that lung does not have to be completely collapsed.

Is there tension? What are the signs? Get them to describe/draw them. Discuss the problems with ventilation in the presence of a ptx and the increased risk of tension

Another example

Is this a tension ptx?

Follow up after tube insertion

You think your patient has a tension pneumothorax? What will you do? Talk about inserting needle, pref large bore angiocath into anterior 2nd intercostal space, Q. How will you find anterior 2nd intercostal space? Q. Having found the anterior 2nd intercostal space, will you go just above, or just below the rib? A. Above. Q. Why? A. The nerve, vein and very importantly, the artery run along the inferior edge of each rib, so you DO NOT want to be poking those things.

www.brooksidepress.org Show them where you go in on the CXR. Avoid the vessels!

Note, this should be a clinical diagnosis! Don’t wait for the CXR http://handbook.muh.ie

Tension ptx on ICU

After needle inserted by ICU staff (see RUL) into second intercostal space. Get them to see if they think all tension has resolved (not, still shift present)