Nagelhout Ch. 28 Thoracic Aortic Aneurysms Flashcards

Questions and Answers

What are the layers of the vessel wall?

Tunica adventitia, media, and intima

What are aneurysms of the adventitia only considered?

False aneurysms (correct)

True aneurysms

Complex aneurysms

Complicated aneurysms

What is a fusiform aneurysm?

A spindle-shaped bulge

What is a saccular aneurysm?

A sac-like bulge on one side Signup and view all the answers

What is an aortic dissection?

Tear within the intima that permits flow of blood through a false passage along the longitudinal axis of the aorta Signup and view all the answers

What is the Debakey Classification for aortic dissection type I?

Originates in the ascending aorta and extends at least to the aortic arch and often to the descending aorta (and beyond) Signup and view all the answers

What does the Stanford classification for aortic dissection type A involve?

Dissections that involve the ascending aorta (with or without extension into the descending aorta) Signup and view all the answers

What is the most common cause of aneurysms?

Atherosclerosis Signup and view all the answers

What are the most common types of aneurysms?

Often descending and distal thoracic aorta, usually fusiform Signup and view all the answers

What are common symptoms of thoracic aortic aneurysms?

Pain, stridor, hoarseness, cough from compression of thoracic structures; aortic insufficiency with ascending aneurysm; diagnosed with CT/MRI Signup and view all the answers

Which type of aneurysm requires CPB or partial CPB for repair?

Resection of ascending aorta and graft replacement Signup and view all the answers

When does the aortic valve need to be replaced?

Sometimes when the aneurysm is close to the aortic arch Signup and view all the answers

When is circulatory arrest needed during aortic surgery?

When cerebral perfusion may be compromised, especially with an aneurysm in the transverse arch Signup and view all the answers

Where should the A-line and pulse ox be monitored during a thoracic procedure?

On the right side Signup and view all the answers

What type of anesthesia is used for thoracic aneurysm repair (descending)?

Double lumen tube, left lateral decubitus position, left thoracotomy Signup and view all the answers

What is the most common factor that leads to dissection or changes in vessel wall integrity?

HTN (Hypertension) Signup and view all the answers

What is the treatment for dissecting aortic lesions type A?

Surgical intervention because they have the highest incidence of rupture Signup and view all the answers

For descending thoracoabdominal aneurysms, at what size is repair recommended?

6 cm or larger Signup and view all the answers

What are poor surgical outcomes related to?

Renal, cardiac, and neuro dysfunction Signup and view all the answers

Pre-op renal function is directly related to what?

Post-op renal failure Signup and view all the answers

What are the most devastating consequences of thoracic aortic surgery?

Paraplegia Signup and view all the answers

Which nerve is related to hoarseness during thoracic surgery?

Left recurrent laryngeal nerve Signup and view all the answers

What kind of ETT is needed for facilitating exposure of the descending thoracic aorta?

Double lumen tube Signup and view all the answers

What is the placement of monitors recommended for a distal arch or thoracic descending aneurysm?

Right A-line and pulse ox placement Signup and view all the answers

What is CSF access?

Lumbar drain may be placed to access CSF pressure Signup and view all the answers

What types of spinal cord injury can occur after surgery?

Immediate or delayed Signup and view all the answers

What are post-op risk factors that increase the risk for spinal cord injury?

Hemodynamic instability, A-fib, bleeding, multiorgan failure, sepsis Signup and view all the answers

What efforts can be made to decrease spinal cord injury during surgery?

SSEP and MEP monitoring, CSF drainage, hypothermia, reattachment of intercostal arteries, distal aortic perfusion Signup and view all the answers

What is spinal cord perfusion pressure?

Arterial BP - CSF pressure Signup and view all the answers

What are the most influential interventions to protect the spinal cord during surgery?

Routine CSF drainage, moderate intra-op hypothermia, optimize cardiac function Signup and view all the answers

What are early complications following thoracoabdominal aortic aneurysm repair?

Respiratory failure, hemorrhage, MI, CHF, early paraplegia, embolism/thrombosis, distal artery occlusion, bowel ischemia, sexual dysfunction, infection, renal failure, CVA Signup and view all the answers

What are late complications following thoracoabdominal aortic aneurysm repair?

Delayed paraplegia, graft thrombosis, fistula formation, false aneurysm, graft infection Signup and view all the answers

What should be done post-op regarding the double-lumen tube (DLT)?

Replace DLT with single lumen, assess for airway edema Signup and view all the answers

Study Notes

Vessel Wall Layers

The vessel wall consists of three layers: tunica adventitia, tunica media, and tunica intima.

Aneurysm Types

False aneurysms involve only the adventitia layer.
Fusiform aneurysms have a spindle-shaped bulge.
Saccular aneurysms feature a sac-like bulge on one side.

Aortic Dissection

Aortic dissection is characterized by a tear in the intima, allowing blood to flow through a false passage.

Dissection Classifications

Debakey Classification:
- Type I: Originates in the ascending aorta, may extend to the aortic arch and descending aorta.
- Type II: Starts and is confined to the ascending aorta.
- Type III: Originates in the descending aorta and extends distally.
Stanford Classification:
- Type A: Involves the ascending aorta.
- Type B: Does not involve the ascending aorta.

Thoracoabdominal Aneurysms

Crawford classification identifies five types based on the anatomical location of the aneurysm relative to the renal arteries and intercostal spaces.

Causes of Aneurysms

Atherosclerosis is the most common cause of aneurysms.
Descending and distal thoracic aorta aneurysms are the most prevalent types, commonly fusiform.

Diagnosis and Symptoms

Symptoms include pain, stridor, hoarseness, and cough due to compression of thoracic structures.
Aortic insufficiency may occur with ascending aneurysms.
Diagnosis is made using CT or MRI imaging.

Surgical Interventions

Resection of the ascending aorta requires cardiopulmonary bypass (CPB) and administration of heparin.
Aortic valve replacement may be necessary when the aneurysm is near the aortic arch.
Circulatory arrest is indicated to protect cerebral perfusion in cases of transverse arch aneurysms.

Anesthesia and Monitoring

Anesthesia for descending thoracic aneurysm repair involves a double lumen tube and a left lateral decubitus position.
A-line and pulse oximetry should be monitored on the right side to avoid complications from left subclavian impingement.

Dissection and Surgical Risks

Hypertension is a significant factor contributing to aortic dissection and vessel wall integrity loss.
Surgical treatment for type A dissections is necessary due to high rupture risk.
Repair of descending thoracoabdominal aneurysms is recommended at sizes of 6 cm or greater.

Postoperative Considerations

Poor surgical outcomes correlate with renal, cardiac, and neurological dysfunctions.
Preoperative renal function is crucial for predicting post-operative renal failure.
Paraplegia is one of the most severe consequences following thoracic aortic surgery.

Neurological Considerations

Hoarseness may occur due to left recurrent laryngeal nerve involvement, which is closely related to the aortic arch.
Establishing CSF access through lumbar drains can help monitor intracranial pressure.
Monitoring spinal cord perfusion pressure is essential; it is calculated as arterial BP minus CSF pressure.

Preventing Spinal Cord Injury

Efforts to mitigate spinal cord injury risk include SSEP and MEP monitoring, CSF drainage, mild hypothermia, and reattachment of intercostal arteries.
Immediate and delayed spinal cord injuries can occur, influenced by dissection type, cross-clamp time, and surgical techniques.

Complications

Early complications post-thoracoabdominal aortic aneurysm repair include respiratory failure, myocardial infarction, and early paraplegia.
Late complications can include delayed paraplegia, graft thrombosis, and infection.

Postoperative Management

After surgery, replace the double lumen tube with a single lumen unless airway edema is observed.
Monitor for recurrent laryngeal nerve damage which could lead to respiratory issues during extubation.

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Description

This quiz focuses on key terms and definitions related to thoracic aortic aneurysms as outlined in Nagelhout Chapter 28. It includes important concepts such as the layers of the vessel wall, types of aneurysms, and aortic dissection. Perfect for students studying vascular anatomy and pathology.