Vascular 2 Flashcards
What should be done for a patient s/p blunt trauma with asymptomatic carotid dissection?
Should be anticoagulated (either heparin or Plavix, not standardized)
Repeat imaging before leaving hospital.
What is the likely treatment for a patient s/p blunt trauma with symptomatic carotid dissection?
Will likely require a covered stent.
What is the prognosis for a patient s/p blunt trauma with traumatic occlusion of the carotid artery?
If already have neurologic injury/completed stroke unlikely to get better with intervention.
Antithrombotic therapy.
What is the required treatment for carotid body tumors?
All require resection.
Consider embolization prior to surgery due to risk of bleeding.
What are the structures of the thoracic outlet in order from anterior to posterior?
Subclavian vein, Phrenic nerve, Anterior scalene, Subclavian artery, Middle scalene, First Rib.
What anatomic anomaly puts patients at risk for thoracic outlet syndrome?
Cervical rib.
Where is the brachial plexus located in relation to the thoracic outlet?
Brachial plexus is along the middle scalene, posterior to the subclavian artery.
Which type of thoracic outlet syndrome (TOS) is most common and what are its classic symptoms?
Neurogenic (95%); pain, weakness, numbness, tingling in the hand, particularly in ulnar distribution; symptoms worse with manipulation/elevation of arm.
What is the treatment for neurogenic TOS?
Physical therapy; confirm with scalene block or nerve conduction test.
1st rib resection + scalenectomy with neurolysis = operation of choice for refractory neurogenic TOS.
What condition does a swimmer with a blue swollen arm likely have and how is it treated?
Subclavian Vein Thrombosis (Paget-Schroetter), compression at costoclavicular junction.
Treatment: catheter directed thrombolysis -> 1st rib resection within the same hospital stay or shortly after.
What is the likely diagnosis for a young person with ischemia of the hand and no atherosclerotic risk factors?
Arterial TOS, though arterial TOS is very rare.
Likely an anomalous cervical rib is compressing the subclavian artery & will lead to an aneurysm, which is an embolic risk.
Tx= 1st rib resection with interposition graft for the artery
Where is the anatomic stenosis that results in subclavian steal?
-Proximal subclavian narrowing
-Reversal of blood flow in vertebral= vertebrobasilar sx
-Sx occur when extremity is exerted= steals blood from cerebral circulation
-Tx= recanalization + stenting or potentially carotid subclavian bypass are subclavian transposition
Reversal of blood flow in vertebral = vertebrobasilar symptoms; symptoms occur when extremity is exerted = steals blood from cerebral circulation.
What is the recommended duration for leaving a temporary catheter in place and why?
3 weeks; infection risk.
How do long-term tunneled catheters differ from temporary catheters?
-Permacath
-They are cuffed & tunneled; lower risk of central infection
-Still higher infection rate & high risk of central venous stenosis compared with fistula or graft
Still higher infection rate & high risk of central venous stenosis compared with fistula or graft.
What is the preferred location for temporary dialysis access?
-Right IJ direct to right atrium
-Avoid side where you plan to place permanent AV Fistula
-Will cause central venous stenosis, will lead to failure of permanent access
Avoid side where you plan to place permanent AV Fistula to prevent central venous stenosis, which will lead to failure of permanent access.
What is the preferred location for AV fistula creation for dialysis access?
-“Fistula First” Always start distal on non-dominant arm, and upper extremities before lower extremities, Start distal to not burn bridges.
-Reducing catheter days, improves life expectancy
-Focus is now moving to choosing the right access for the right person, a person with a short life expectancy, a fistula may not be the best access
Start distal to not burn bridges; reducing catheter days improves life expectancy.
What is the most common reason for AV fistulas to malfunction over time?
Venous outflow problems.
What is the likely problem if a patient reports high venous return pressures and increased bleeding after dialysis?
-Likely has venous outflow stenosis
-Dx: duplex US
-Tx: Fistulogram with balloon angioplasty
Diagnosis: duplex US; Treatment: Fistulogram with balloon angioplasty.
What are the criteria for fistula maturation, known as the ‘Rule of 6s’?
Needs to be 6 mm in diameter, less than 6 mm deep, greater than 600 mL/min in flow.
What are some likely causes of failure to mature in a brachio-cephalic fistula 6 weeks after creation?
-Possible inadequate inflow, r/o stricture at anastomosis, potential balloon angioplasty vs revision of anastomosis
-Competing flow from side branches, branches need to be ligated or coiled
Competing flow from side branches may require ligation or coiling.
How can a bleeding fistula with pinpoint hole bleeding be treated?
Can be treated with a stitch and urgent fistulogram.
Bleeding from an ulcer on a fistula is a surgical emergency.
Bleeding from an ulcer on a fistula is a surgical emergency.
When are fasciotomies indicated and what are the symptoms?
-In a patient with documented lower extremity compartment syndrome
-A patient that had acute limb ischemia for > 4 hours, should be considered for prophylactic fasciotomy
-Patients will have tight compartments, pain with passive motion of foot
A patient that had acute limb ischemia for > 4 hours should be considered for prophylactic fasciotomy; symptoms include tight compartments and pain with passive motion of foot.
Where should the incision be made to access anterior and lateral compartments?
-Make incision lateral to tibia in between the tibia and
fibula (H type incision to pen both anterior and lateral compartments, incisions should be anterior and posterior to intermuscular septum.
What nerve can be injured with the lateral incision and what deficit would you see?
Superficial peroneal nerve which can lead to difficulties with foot eversion.
How do you access superficial posterior and deep posterior compartments?
-Make incision two centimeters posterior/medial to tibia
-The key to perform a complete four-compartment fasciotomy is to make sure that the posterior deep compartment has been fully decompressed. Both the superficial and the deep posterior compartments are decompressed through the medial incision.
The key to perform a complete four-compartment fasciotomy is to ensure that the posterior deep compartment has been fully decompressed.
How do you release the deep posterior compartment?
Take soleus off of the tibia.
In a blunt thoracic aortic injury, where is the most common site of injury?
-Just distal to subclavian artery in the descending thoracic aorta, at the level of the ligamentum arteriosum, the aorta is tethered here
-A pseudoaneurysm develops here (partial transection)
-Treated with TEVAR
What are the size criteria for treating descending thoracic aortic aneurysms?
-If endovascular repair is possible if > 5.5 cm
-Otherwise aorta should be > 6.5 cm
What is a feared complication of thoracic aorta repairs?
-Paraplegia (<5% for endovascular vs 20% for open)
-Reduce this risk by placing lumbar drains and increasing the blood pressure
-Spinal Perfusion Pressure = MAP (drive up with pressors) – ICP (lower with spinal drain)
Reduce this risk by placing lumbar drains and increasing the blood pressure.
What are the four types of acute mesenteric ischemia?
Embolic, thrombotic, venous thrombosis, non-occlusive mesenteric ischemia.
Which type of mesenteric ischemia is most common and how do you diagnose and treat it?
-Embolic is most common, likely from afib or endocarditis
-Patients will have severe abdominal pain, with no other supporting findings on exam (pain out of proportion to exam)
-CTA is best modality to diagnose
-Heparinize the patient and take to OR for ex lap and SMA embolectomy
-Best to leave abdomen open, re-explore in 12-24 hours before resecting any marginally perfused bowel
Patients will have severe abdominal pain, with no other supporting findings on exam; CTA is best modality to diagnose; Heparinize the patient and take to OR for ex lap and SMA embolectomy.
What type of mesenteric ischemia is most common in patients with severe atherosclerotic disease burden?
-Thrombotic disease
-This likely occurs at ostium/takeoff of the SMA
-Embolic disease is more distal, generally at first branch of SMA
-Pts with thrombotic AMI, likely have had unrecognized symptoms for months – years
-These patients will likely require a mesenteric bypass rather than embolectomy
Which disease process, embolic or thrombotic, will have proximal jejunal sparing?
-Embolic because it lodges just distal to first branch of SMA (3-10 cm distal to ostium)
-Thrombotic patients will not have any sparing of small intestine
What are the characteristics of mesenteric venous thrombosis?
-Sub-acute, multiple days of abdominal pain and bloody diarrhea
-Generally have an underlying hypercoaguable disorder
-CTA will demonstrate small bowel wall thickening, mesenteric edema, and thrombosis of SMV
-Heparinize patients, rarely need surgery, only for resection of ischemic bowel
Generally have an underlying hypercoagulable disorder; CTA will demonstrate small bowel wall thickening, mesenteric edema, and thrombosis of SMV.
What are the characteristics of non-occlusive mesenteric ischemia (NOMI)?
-Critically ill, on multiple pressors and may have cardiac failure
-Ischemia is in watershed areas (splenic flexure and upper rectum)
-Tx: resuscitation + improvement of cardiac functions
-Only OR if need to resect ischemic bowel
Ischemia is in watershed areas (splenic flexure and upper rectum); Treatment: resuscitation + improvement of cardiac functions.
What is the most common site for an upper extremity embolus to lodge?
Brachial artery at bifurcation of radial and ulnar artery.
What is the most common site for a lower extremity embolism to lodge?
Common femoral artery at bifurcation of profunda and SFA.
In a patient with a ruptured AAA with hypotension undergoing a crash laparotomy, where should you get proximal control?
Supraceliac aorta through the gastrohepatic ligament, underneath crus of diaphragm, press aorta against spine.
