emergencies in the chest - warszawski uniwersytet...

EMERGENCIES IN THE CHESTMichal Kozub

CHEST IMAGING

1.Consolidation - any pathologic process that fills the alveoli with fluid, pus, blood, cells (including tumor cells) or other substances resulting in lobar, diffuse or multifocal ill-defined opacities.2.Interstitial - involvement of the supporting tissue of the lung parenchyma resulting in fine or coarse reticular opacities or small nodules.3.Nodule or mass - any space occupying lesion either solitary or multiple.4.Atelectasis - collapse of a part of the lung due to a decrease in the amount of air in the alveoli resulting in volume loss and increased density.

http://www.radiologyassistant.nl/en/p50d95b0ab4b90/chest-x-ray-lung-disease.html

CHEST RADIOGRAPH

• Portable chest radiography is the initial imaging method used at the emergency workup of the polytrauma patient and it is useful for detecting serious life-threatening conditions, such as a tension pneumothorax or haemothorax, mediastinal haematoma, flail chest or malpositioned tubes.

Usually AP

Often supine

Frequently in poor inspiration

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259

405/

CT• The superiority of CT over chest radiography

has been documented in the literature.

• CT detects significant disease in patients with normal initial radiographs and in 20% will reveal more extensive injuries compared with the abnormal initial radiographs, necessitating a change of management. Reformats without additional scanning.

Usually on spontaneous breath

Motion artifact

Metal artifact/high-density foreign material artifact

MRI

• MRI allows the radiologist to directly evaluate the soft tissues of the spine and is, therefore, crucial in the evaluation of the patient with ligamentous injury and instability.

a prolonged acquisition time

unavailability at many institutions

contraindications, including patients with pacemakers, ferromagnetic aneurysm clips, metallic fragments in the spinal cord, and claustrophobia.

http://www.radiologyassistant.nl/en/p49021535146c5/spine-cervical-injury.html

MRI in acute spinal trauma By Michael C. Hollingshead, MD, and Mauricio Castillo, MD, FACR

MRI

• When computed tomographic angiography (CTA) is contraindicated, MRI and MRA are important alternative imaging modalities for diagnosis and management of patients with acute PE, AD and MI.

Hochhegger B, Ley-Zaporozhan J, Marchiori E, et al. Magnetic resonance imaging findings in acute pulmonary embolism. The British Journal of Radiology. 2011;84(999):282-287. doi:10.1259/bjr/26121475.

ULTRASOUND????

Focused Assessment Sonography for Trauma (FAST)

Since CT has better accuracy for diagnosing torso injuries, the FAST exam is most useful in situations where CT is not practical due to time constraints or when CT scan can be reasonably avoided.

https://www.acep.org/content.aspx?id=91918

CLINICAL SCENARIOS WHERE „FAST” IS MOST USEFUL:

• Hemodynamically unstable patients, when the cause of hypotension is unclear.

• Patients who need an emergent bedside procedure.

• Patients at a community hospital who require transfer to a trauma center. Consider pericardiocentesis if a pericardial effusion is found, consider early blood transfusion for significant hemoperitoneum, and consider a chest tube if a hemothorax or pneumothorax is discovered, especially if aeromedical transport is planned.

• Intoxicated patients who can be observed and re-examined.

• Patients with penetrating trauma with multiple wounds or unclear trajectory, especially with wounds in upper abdomen or lower chest.

• Patients with a concerning mechanism of injury but no indication for CT. Consider a period of observation and serial FAST exams.

http://www.supertechx-ray.com/Ultrasound/TrainingPhantoms/FASTERFAN.php

CHEST EMERGENCIES

•Trauma

•Non traumatic emergencies

TRAUMA

• Lung trauma

• Pulmonary contusions

• Pulmonary lacerations

• Traumatic lung herniation

• Torsion of the lung

• Pneumothorax

• Haemothorax

• Haemopneumothorax

• Tracheobronchial injuries

• Mediastinal

• Pneumomediastinum

• Mediastinal haematoma

• Aortic injury

• Oesophageal injuries

• Thoracic duct trauma

• Cardiac trauma

TRAUMA

• Skeletal trauma

• Rib fractures

• Flail chest

• Sternal fractures

• Scapula fractures

• Thoracic spine fractures

• Diaphragmatic trauma

• Diaphragmatic injuries

Oikonomou A, Prassopoulos P. CT imaging of blunt chest trauma. Insights into Imaging. 2011;2(3):281-295.

doi:10.1007/s13244-011-0072-9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259405/

NON TRAUMA

• Pulmonary embolism

• Pneumothorax ( tensionpneumothorax )

• Airway foreign bodies

• Pneumoperitoneum

• Pericardial effusions

• Acute respiratory distress syndrome

• Thoracic aortic aneurysms

• Diaphragmatic hernias

• Congestive heart failure

• Aspiration pneumonia

• Hydropneumothorax

ATELECTASIS• Atelectasis, (also called collapse), a loss of

volume of lung parenchyma caused by a reduced inflation. Some mechanisms may be responsible for atelectasis:• bronchial obstruction• extrinsic compression such as pleural fluid or air,

or the presence of any space-occupyingintrathoracic lesion resulting in extrinsiccompression of adjacent parenchyma;

• cicatrization atelectasis resulting from lungparenchymal fibrosis;

• adhesive atelectasis resulting from loss of surfactant.

ATELECTASIS• The most frequent cause of

atelactasis is bronchial obstruction.

• The major radiological signs of atelectasis are opacity of the lobe/lung and evidence of loss of volume. Opacity results from the presence of intra-alveolar fluid in the case of obstructive atelectasis or passive atelectasis or from scarring or lung fibrosis in the case of cicatrization atelectasis.

ATELECTASIS

The signs of loss of volumeinclude:• displacement of fissures,

pulmonary blood vesselsand major bronchi,

• Shift of other structures to compensate for the loss of volume.

• In the case of obstructiveatelectasis, the presenceof a large tumour mass located in a parahilarsituation may produce a bulge in the contour of the collapsed lobe (golden S sign)

ATELECTASIS OF RIGHT UPPER LOBE

• The right hilum becomes elevated;

• The major and minor fissures are displacedupwards and rotatedtowards the mediastinum. As a result, the collapsedlobe packs against the mediastinum and lungapex.

ATELECTASIS OF LEFT UPPER LOBE• The hilum is displaced

upwards and the major fissure forwards (next slice).

• The lobe retains much of its original contact with the anterior chest wall.

• Displacement of the anterior mediastinum fat and displacement of the trachea towards the left are commonly present.

• The left hemidiaphragm is moderately elevated

ATELECTASIS OF MIDDLE LOBE• The collapsed right

middle lobe is easily recognized on the lateral chest radiograph.

• The major and minor fissures move towards one another and the collapsed lobe resembles a curved, elongated wedge.

• The right hilum is not displaced. The right hemidiaphragm and mediastinum are in a normal position.

ATELECTASIS OF LOWER LOBE

• The lower lobe collapse is seen with obstruction to lower lobe’s bronchus.

• The major fissure is displaced downward and backward creating an opacity that obliterates the dome of the hemidiaphragm.

• Ipsilateral hilum, mainstem bronchus and upper lobar bronchus are displaced downward.

AIRWAY FOREIGN BODIES

• Airway foreign bodies are most often found in pediatric patients.

• The most common site of foreign bodies is the right mainstem bronchus due to its posterior location, shallow angle to the trachea and wide diameter. The density of the ingested item will determine whether it can be directly identified on radiographs.

http://reference.medscape.com/

AIRWAY FOREIGN BODIES

• Indirect signs of ingestion include:

• focal overinflation (if there is partial obstruction),

• atelectasis (if there is more complete obstruction).

PERICARDIAL EFFUSIONS

• Pericardial effusions result from the accumulation of fluid within the pericardial space.

PERICARDIAL EFFUSIONS

• The classic finding on a chest radiograph is an enlarged cardiac silhouette, the so-called water-bottle heart.

• However, if the fluid accumulates rapidly, then minimal cardiomegaly may be present.

• Other potential findings include pleural effusion and rarely pericardial calcifications.

https://radiopaedia.org/articles/pericardial-effusion

ACUTE RESPIRATORY DISTRESS SYNDROME

• ARDS defined by the American/European Consensus Committee, as

• acute and persistent severe hypoxia,

• bilateral radiographic lung infiltrates,

• no evidence of congestive heart failure.

• Patients with lesser degrees of hypoxia are classified as having acute lung injury.

ACUTE RESPIRATORY DISTRESS SYNDROME• ARDS is not a disease but a syndrome that

may be due to direct parenchymal injury (trauma, pneumonia, aspiration) or due to capillary leak oedema from systemic inflammation (sepsis, hypotension)

• The clinical approach to and radiographic understanding of ARDS has assumed that the type of underlying injury was not relevant to life support strategies and imaging interpretation.

• Recent evidence suggests that lung mechanics and radiographic appearance may be different in those with ARDS due to pulmonary causes (ARDSp) and those with ARDS due to extrapulmonary causes.

THE CLASSICAL RADIOGRAPHIC DESCRIPTIONS OF ARDS

• During the first 12-24 hours after a systemic insult, the chest radiograph is normal or it shows mild generalized atelectasis.

• Over the next 48 hours, there is a rapid increase in density throughout the lungs and often diffuse ground-glass to alveolar consolidation symmetrically distributed.

• The appearance then stabilizes for several days. Toward the end of the first week, the consolidation becomes less dense, eventually forming a fibrotic pattern.

ACUTE RESPIRATORY DISTRESS SYNDROME• The classical radiographic

descriptions of ARDS are as follows:

• During the first 12-24 hours after a systemic insult, the chest radiograph is normal or it shows mild generalized atelectasis.

• Over the next 48 hours, there is a rapid increase in density throughout the lungs and often diffuse ground-glass to alveolar consolidation symmetrically distributed.

• The appearance then stabilizes for several days. Toward the end of the first week, the consolidation becomes less dense, eventually forming a fibrotic pattern.

CT shows bilateral diffuse ground-glass opacification of ARDS due to sepsis. There is also pneumomediastinumdue to barotrauma

CT shows

asymmetrical

consolidation from ARDS due to

bacterial

pneumonia

ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS)

• The most common findings on chest radiographs are bilateral, predominately peripheral, asymmetric consolidations with air bronchograms.

• Septal lines and pleural effusions are uncommon findings.

• Early findings during the exudative phase are bilateral consolidations that obscure the pulmonary vascular markings. These opacities extend to more extensive diffuse consolidations that are typically asymmetric.

• Most radiographic abnormalities begin to resolve after 10-14 days if the patient survives.

CONGESTIVE HEART FAILURE

• Congestive heart failure is a clinical syndrome in which the heart fails to adequately pump blood to tissues.

• A number of typical findings may be present on a chest radiograph:

• With cardiomegaly, the cardiothoracic ratio increases to greater than 50% on a posterior-anterior chest radiograph.

• Kerley B lines may be present on the lung periphery that are the result of interlobular septal thickening.

• Accumulated pleural fluid may blunt costophrenic angles or cause large pleural effusions.

• With cardiomegaly, the cardiothoracic ratio increases to greater than 50% on a posterior-anterior chest radiograph .

Kerley B lines may be present on the lung periphery that are the result of interlobular septal thickening.

Accumulated pleural fluid may blunt

the costophrenic angles or cause large

pleural effusions.

Pulmonary edema may cause bilateral

increased lung markings in a perihilar,

or bat-winged, distribution. Increased

pulmonary capillary pressure causes

the upper lobe vessels to be equal or

larger in caliber than the lower lobe

vessels, referred to as cephalization.

PULMONARY OEDEMA• Abnormal accumulation of fluid in the interstitial

compartment of the lung with or without associated air-space filling.

• The oedema is due to changes in hydrostatic forces in the capillaries, to increased capillary permeability or to impaired lymphatic drainage.

• Transudative pulmonary oedema is due to increasedhydrostatic pressure or, rarely, due to decreased oncoticpressure across a functioning capillary membrane.

• Hydrostatic pulmonary oedema can result from cardiogenic or noncardiogenic (renal failure, fluid overload) causes.

• Cardiogenic pulmonary oedema is a consequence of elevated left-sided pressure which may result from leftventricular dysfunction, mitral valve disease, left atrialdisease or, rarely, pulmonary venous obstruction.

PULMONARY OEDEMA

• The radiographicchanges of hydrostaticoedema are quitecharacteristic.

• "cephalization" with the upper lobe vesselsbecoming larger thanthe lower lobe vessels

• In left heart failure, the artery enlarges relativeto the bronchus. Sincethey are in the same plane, magnification isnot an issue.

PULMONARY OEDEMA

The upper lobe pulmonary

vessels are enlarged.

Peribronchial cuffing is seen in

the anterior segmental bronchus

of the left upper lobe. There is a

moderate right pleural effusion in

the major and minor fissures.

There is a moderate

subpulmonary effusion on the

left.

PULMONARY OEDEMA

Posteroanterior radiograph of

a 14-year-old child with an

acute cardiomyopathy. The

airspace shadowing, which is

more severe on the right, is

typical of pulmonary

oedema.

PULMONARY OEDEMA

• The radiograph in cardiogenicpulmonary oedema may show cardiomegaly, alteration of cardiaccontour due to congenital heart diseaseor abnormality of the pulmonaryvasculature due to a right-to-left shunt.

• The earliest radiographic change visiblein increased pulmonary venous pressureis redistribution of blood flow, with anincrease in prominence of the normallysmaller upper lobe vessels. Also, the supine film does not allow detection of any change in distribution.

PULMONARY OEDEMA

cardiogenic pulmonary oedema

THORACIC AORTIC ANEURYSMS

• Thoracic aortic aneurysms are defined as a greater than 50% aneurysmal dilatation of normal ascending thoracic aorta, aortic arch, or descending thoracic aorta.

• The descending thoracic aorta is the most common site.

http://www.cardiachealth.org/thoracic-aortic-

aneurysm


• On chest radiographs, the most common findings are a widening of the mediastinal silhouette (white arrow), enlargement of the aortic knob and tracheal displacement (red arrow).

• Other radiographic findings include a double-opacity appearance to the aorta representing true and false lumens, localized bulges along the aortic contour and a disparity in the caliber of the descending and ascending aorta.

http://reference.medscape.com/features/slideshow/chest-radiography#9

AORTIC DISSECTION

• Splitting of the media of the aortic wall by blood. It may occur by means of a tear in the aortic intima with blood passing from the lumen into the wall causing the intima to be torn from the wall for a variable distance. Dissection may also occur by spontaneous bleeding of the vasa vasorum causing intramural haematoma without rupture of the intima and consequently no connection between the lumen and the intramural dissection.

AORTIC DISSECTION

• Degeneration of the aortic media, cystic medial necrosis, is the pathological substrate for aortic dissection. This may be induced by chronic stress against the wall such as occurs with systemic hypertension, aortic coarctation, aorticstenosis and bicuspid aortic valve. Cystic medial necrosis is a feature of hereditary defects of connective tissue, especially Marfans syndrome and Ehlers Danlos syndrome. The risk of dissection is increased during pregnancy.

AORTIC DISSECTION

• There are two classifications of aortic dissection. The Stanford classification recognizes Type A (involvement of ascending aorta alone or involvement of ascending and descending aorta) and Type B (involvement of descending aorta alone). The De Bakey classification describes Type I (ascending and descending aorta), Type II (ascending aorta alone) and Type III (descending aorta only). Stanford A and De Bakey I and II are treated by emergency surgery.

AORTIC DISSECTION

Diagram

showing the

two

classification

systems.

Stanford

Type A

includes

DeBakey

Type I and II

AORTIC DISSECTION - IMAGING

• The chest X-ray is neither sensitive nor specific for establishing the diagnosis of aortic dissection.

• The chest radiograph frequently demonstrates anenlarged thoracic aorta as a consequence of underlyingpredisposing diseases such as hypertension or aorticvalvular disease.

• The chest X-ray may display features indicative of Marfans syndrome such as sternal deformity, scoliosis and elongated thorax.

• Infrequently, the chest X-ray may demonstrate inwarddisplacement of intimal calcification in the aortic arch on the frontal view or an apical pleural cap.

THE DEFINITIVE DIAGNOSIS OF AORTIC DISSECTION CAN BE ESTABLISHED BY:

• thoracic aortography,

• computed tomography angiograhy,

• magnetic resonance imaging angiograhy,

• echocardiography.

AORTIC DISSECTION - IMAGING

The goals of imaging studies in the typical dissection are to identify:

• the intimal flap;

• extent of the dissection;

• involvement of aortic branches;

• patency of the false channel;

• periaortic hematoma or haemorrhagic pericardial effusion;

• aortic regurgitation.

AORTIC DISSECTION

AORTIC DISSECTION

Partition of a

three-dimensional

contrast-

enhanced MRA

shows intimal flap

(arrows) in the

distal aortic arch

and descending

aorta.

AORTIC DISSECTION

• CT angiography, and MR angiography are highly sensitive and specific for the diagnosis of aortic dissection. They display the presence and extent of the intimal flap and the sizes and configurations of the true and false channels.

• Because of limitations in acquiring diagnostic images in some subjectsand lower diagnostic accuracy, transthoracic echocardiography hasbeen replaced by transoesophageal echocardiography.

• The portability of transoesophageal echocardiography is a highlyattractive attribute since it can be taken to the patient in the emergency department or intensive care unit.

PULMONARY EMBOLISM (PE)

• Embolic occlusion of the pulmonary arterial system.

• The majority of cases result from thrombotic occlusion and therefore the condition is frequently termed pulmonary thrombo-embolism

• Clinical signs and symptoms are non-specific. Dyspnoea, chest pain, and haemoptysis have been described as a classic triad in pulmonary embolism.

• 2 scores: Wells score, Geneva score.

• Markers: D-dimer (normal D-dimer has almost 100% negative predictive value (virtually excludes PE): no further testing is required.

• Raised D-dimer is caused by many other diseases than PE = Raised D – Dimer is non-specific: it indicates the need for further testing if pulmonary embolism is suspected)!

PULMONARY EMBOLISM (PE)

• Risk factors

• primary hypercoagulable states (protein C or S deficency, antithrombin III deficiency)

• recent surgery

• pregnancy

• prolonged bed rest / immobility

• malignancy

• oral contraceptive use

PLAIN RADIOGRAPH

• Fleishner sign: enlargedpulmonary artery (20%)

https://radiopaedia.org/articles/fleischner-sign-1

PLAIN RADIOGRAPH• Hampton hump: peripheral

wedge of airspace opacityand implies lung infarction(20%)

https://radiopaedia.org/articles/hampton-hump-2

PLAIN RADIOGRAPH

• Westermark's sign: focal peripheral hyperlucency secondary to focalhypovolemia

• pleural effusion (35%)

• elevated diaphragm

https://radiopaedia.org/articles/westermark-sign

CT PULMONARY ANGIOGRAPHY (CTPA)

• shows filling defects within pulmonary vasculature with acute pulmonary emboli

NUCLEAR MEDICINE

• VQ scan will show ventilation-perfusion mismatches.

MRI???

MR findings for acute PE were similar to those seen by CT or

angiography, because all provided morphological

representations of the same pathological process. We

classified the MR features of pulmonary thromboembolism

as vascular signs or parenchymal sign:

• Pulmonary arterial signs

• Signs of pulmonary hypertension

• Collateral systemic supply

• Parenchymal signs

A meta-analysis of studies that adopted gadolinium-

enhanced MR for imaging acute PE used conventional

pulmonary angiography as the reference standard. A

broad range of sensitivities, from 77% to 100%, was reported,

with uniformly high specificities of 95% to 98%.

Hochhegger B, Ley-Zaporozhan J, Marchiori E, et al. Magnetic resonance imaging findings in acute pulmonary embolism. The British Journal of Radiology. 2011;84(999):282-287. doi:10.1259/bjr/26121475.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3473863/

DIAPHRAGMATIC HERNIAS

• Diaphragmatic hernias are caused when a defect in the diaphragmatic wall allows for the herniation of abdominal contents into the thoracic cavity.

• The majority of tears are on the left side and are thought to represent either weakness of the left hemidiaphragm or protection by the liver.

DIAPHRAGMATIC HERNIAS

• On chest radiographs, asymmetry of hemidiaphragm or changing diaphragmatic levels may be present (arrows).

• Gas-filled organs or a nasogastric tube within thoracic cavity will confirm the diagnosis. Solid abdominal organs will appear as mushroom-shaped homogeneous opacities.

• Potential misdiagnosis can occur in the case of diaphragmatic paralysis or after lung reduction surgery.

HEMITHORAX WHITE-OUT

• Complete white-out of a hemithorax on the chest x-ray has a limited number of causes.

• The differential diagnosis can be shortened further with one simple observation - the position of trachea.

• Is it central, pulled or pushed from the side of opacification?

TRACHEA PULLED TOWARD THE OPACIFIEDSIDE

• Pneumonectomy

• total lung collapse: e.g. endobronchial intubation

• pulmonary agenesis

• pulmonary hypoplasia

TRACHEA REMAINS CENTRAL IN POSITION

• Consolidation

• pulmonary oedema/ARDS

• pleural mass: e.g. mesothelioma

• chest wall mass: e.g. Askin/Ewingsarcoma

PUSHED AWAY FROM THE OPACIFIED SIDE

• pleural effusion

• diaphragmatic hernia

• large pulmonary mass

Pneumoperitoneum

• Pneumoperitoneum refers to air within the

peritoneal cavity, most commonly from

perforation of an abdominal viscus.

• Air will accumulate in the least dependent

portion of abdominal cavity.

• During upright chest radiographs, air will

separate liver, spleen and intestines from

diaphragm producing dark crescents.

• To ensure adequate air migration, patients

should be kept upright for at least 5

minutes before the image is taken.

THANKS FOR ATTENTION

THANKS FOR ATTENTION

• http://www.radiologyassistant.nl

• https://radiopaedia.org/

• Hochhegger B, Ley-Zaporozhan J, Marchiori E, et al. Magneticresonance imaging findings in acute pulmonary embolism. The British Journal of Radiology. 2011;84(999):282-287. doi:10.1259/bjr/26121475.

• Oikonomou A, Prassopoulos P. CT imaging of blunt chest trauma. Insights into Imaging. 2011;2(3):281-295. doi:10.1007/s13244-011-0072-9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259405/

• ECR 2008 / C-275Blunt chest trauma: Spectrum of findings with emphasis on MDCT

emergencies in the chest - warszawski uniwersytet...

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