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118 Cards in this Set

  • Front
  • Back
Organs effected by sequelae of PVD
Brain
Kidneys
Mesentery
limbs
Predisposing Factors to Atherosclerosis
Abdominal obesity
Atherogenic dyslipidemia
Elevated blood pressure
Insulin resistance - DM
Pre-inflammatory state
Prothrombotic state
SMOKING
Benefits of statins in atherosclerosis
May reduce progression or even cause regression of athersclerotic plaque

Improves endothelial function and reduces cardiovascular events in high risk patients
Benefits of ACEI's in pts with atherosclerosis
Plaque stabilization
Also associated with decreased long term mortality in patients undergoing infra inguinal bypass
most effective medical therapy for atherosclerosis
stop smoking!
do you d/c ASA the day of surgery?
nope.

Just the antiplt (plavix) 7 days before.
the leading cause of extracranial vascular cerebral events
Carotid atherosclerosis
In carotid atherosclerosis...Atherosclerotic plaque usually develops
at the lateral aspect of carotid artery bifurcation

and commonly extends into the internal and external carotid arteries
Symptomatic high grade stenosis –

Symptomatic moderate stenosis –

Asymptomatic high grade stenosis -
Symptomatic high grade stenosis – 70-99% of artery is blocked

Symptomatic moderate stenosis – 50 – 70% of artery is blocked

Asymptomatic high grade stenosis ≤ 60% of artery is blocked
What is Amaurosis fugax?
A manifestation of carotid atherosclerosis.

Monocular blindness in the ipsilateral eye as the stenosed carotid artery.

“Felt like someone pulled a shade down over eye”

Blockage of the optic artery on the ipsilateral side.
Clinical Manifestations of Atherosclerotic Carotid Arteries?
Asymptomatic bruit (requires a doppler study)

Amaurosis fugax

TIAs

Dizziness when head is extended back
What are the three major blood vessels that supply the brain?
1) Two INTERNAL CAROTID ARTERIES: branch off from the common carotid arteries and bifurcate into the anterior and the middle cerebral artery in the brain. These also branch into the opthalamic artery.

2) Two VERTEBRAL ARTERIES: branch from the subclavian arteries at the posterior aspect of the neck. In the brain they fuse into the basilar artery, which becomes the posterior cerebral artery.

3) The CIRCLE OF WILLIS: Provides backup circulation to the brain via the posterior communicating arteries. ...interconnects all of the arteries that supply the brain.
The internal carotid arteries are _______ circulation and branch into the _______ cerebral arteries.

The vertebral arteries are _______ circulation and branch into the _____ cerebral arteries.
The internal carotid arteries are ANTERIOR circulation and branch into the ANTERIOR AND MIDDLE cerebral arteries.

The vertebral arteries are POSTERIOR circulation and branch into the POSTERIOR cerebral arteries.
The 4 major structures in the carotid sheath are...
* the common carotid artery as well as the internal carotid artery
* internal jugular vein
* the vagus nerve(CN X)
* the deep cervical lymph nodes.
What nerves are found in the carotid sheath?
Nerves 9-12

Glossopharyngeal Nerve (IX)
Vagus Nerve (X)
Accessory Nerve (XI)
Hypoglossal Nerve (XII)
Ways to diagnose carotid atherosclerosis
Duplex ultrasound (most sensitive)
CT scan
MRI
Angiogram

Carotid and cerebral angiography will identify type of lesion (ulcerative or stenotic), its location, and extent of collateral circulation. Other commonly used techniques include MR angiography, CT angiography, and duplex ultrasonography. As part of the preop evaluation, the anesthesiologist should examine the angiograms of the patient or discuss the case with the surgeon in order to understand with type, location, and extent of the lesion.
Where does the vagus nerve lie in the carotid sheath?
In b/n the internal jugular vein and the common carotid artery.
How do you position a pt for a carotid endarterectomy?
* Shoulder blades must be extended (role under the shoulder blades…drop them back and hyperextend the neck.

* Need something to elevate the pts shoulders to hyperextend the neck. (towels under the neck/ shoulders.
(Becareful to assess for cervical arthritis before doing this. )

* Head must be turned to opposite side from operation.

* ETT must be taped on opposite side of the face from operative site.

* Put them in that pos before they go to sleep...make sure no dizziness....that means they are occluded in that position!!
Risks of shunting for a CAE
* Have to clamp both sides...clamps can damage/ tear the arterial wall.

* Might break off plaque and cause an emboli/ stroke.

* Incision will be longer.
How do you evaluate the function of the hypoglossal nerve?
* Listen to articulation.
* Inspect tongue in mouth for wasting, fasciculations.

* Protrude tongue: unilateral deviates to affected side.
How do you evaluate the function of the vagus nerve?
* Voice: hoarse or nasal.

* Pt. swallows, coughs (bovine cough: recurrent laryngeal).

* Examine palate for uvular displacement. (unilateral lesion: uvula drawn to normal side).

* Pt says "Ah": symmetrical soft palate movement.

* Gag reflex [sensory IX, motor X]:
• Stimulate back of throat each side. • Normal to gag each time.
How do you evaluate the function of the glossopharyngeal nerve?
* Voice: hoarse or nasal.

* Pt. swallows, coughs (bovine cough: recurrent laryngeal).

* Examine palate for uvular displacement. (unilateral lesion: uvula drawn to normal side).

* Pt says "Ah": symmetrical soft palate movement.

* Gag reflex [sensory IX, motor X]:
• Stimulate back of throat each side. • Normal to gag each time.
How do evaluate the function of the Accessory Nerve?
* From behind, examine for trapezius atrophy, asymmetry.
* Pt. shrugs shoulders (trapezius).
* Pt. turns head against resistance: watch, palpate SCM on opposite side.
The walls of the arteries in a stenosed carotid artery are _____. This requires what?
The walls of stenosed carotid arteries are then..this imposes the risk of restenosis...so it required a graft with surgery.

Downside: you can get an intimal flap. ...Happens more with patch grafts.
Normal cerebral blood flow
50 ml /100 g/min

CPP = MAP – ICP
Range of MAP for autoregulation of cerebral blood flow
50 – 150 mmHg
Cerebral steal
Intracerebral steal, a term popularized by Symon (Symon, 1968), refers to the paradoxical decrease of flow in the ischemic areas in response to vasodilator stimuli.
CAE is what level of risk of M/M from ischemic heart intraop?
Intermediate risk
< 5%
Predictors of Morbidity and mortality during a CAE?
* Age > 75 y/o
* Experience of the surgeon
* Pre-op neuro symptoms
* Previous stroke – residual effects
* History of angina – perioperative
ischemic events
* Diastolic BP > 110 mm Hg preop: cancel sx
* CEA performed in preparation for CABG. (Normally this does not happen…MI/ stroke rates are much higher. It depends on the stenosis and how bad it is.)
* Internal carotid artery thrombus
* Stenosis near the carotid siphon
* Bilateral carotid disease.
* Contralateral carotid occlusion
Explain BP control intraop for CAE's
What a tight BP control. Want BP to be 10-20% above baseline.

Take BP in both arms and put cuff on the arm with the highest pressure.

Use clonidine or ACEI's to control BP.

After incision is closed...BP must be controlled to pvt bleeding.
What is the major postop complication of CAE and significant mortality and morbidity?
A Perioperative MI

Incidence is 1%
What is involved in a respiratory assessment of someone for a CAE?
* Smoking should be stopped for 24 hours.
* Get a chest xray and look for pulmonary infiltrates, cardiomegally.
* Get an ABG, PFTs if needed.
* Any pulmonary infection should be treated preop.
During a neuro assessment before a CAE, your patient extends head back and gets dizzy and passes out. What can you conclude?
The pt has bilateral occlusion of the carotid arteries.

(Extending the head back occludes the basilar artery...so if you pass out that means you have not blood from from the carotids either.).
How important is a neuro assessment before a CAE? What are you looking for?
must be perfomred by all CRNA's and documented, regardless of whether it has already been done!!!

Be on the lookout for contralateral occlusions/ disease, bilateral occlusions, residual weakness from a stroke, bruits...get a doppler study.

Look for collateral circulation around occlusions in a duplex ultrasonography, angiography, or a CT scan.

Also need to do and document a post op neuro assessment for each pt.
Hematology tests required before an CAE?
HgB / Hct
Platelet count
PT & INR; PTT (if on wafarin)
Type X-match (although blood loss is minimal…plan for the worst).
What is the proper way to assess a person's cerebrovascular flow before a CAE?
Manual occlusion of the carotid arteries is not an appropriate test of tolerance to temporary circulatory occlusion, as it may endanger the patient by precipitating embolization from an ulcerative lesion or by inducing bradycardia and ↓BP from activation of the carotid sinus reflex. It is desirable, however, to position the patient's head in the operative position as a test of the effect of that position on CBF. It is well-documented that hyperextension and lateral rotation of the head may occlude vertebral-basilar flow and, if sustained, contribute to postop cerebral ischemia. Sx of dizziness or diplopia will emerge with this maneuver if CBF is compromised.
What things can interfere with the post op neuro exam?
Sedatives
Opiods
Hypercarbia/ Hypoxia
Describe induction for a CAE
Avoid HTN

ie...use lidocaine and opiods to blunt SNS response to DL. Use an LTA kit. Use clonidine.

Make sure pt has taken their BP meds.
Two main goals of intra-op management and monitoring during a CAE
Protect the brain
Protect the myocardium
What is a big obstacle during mainenance of a pt during a CAE in regards to the heart and brain?
Maintaining a balance b/n supply and demant to both can be in conflict of each other.

Increasing blood pressure to augment cerebral blood flow (CPP - MAP-ICP) can increase afterload and/or myocardial contractility and increase MVO2.

Although hypothermia provides cerebral protection, it also poses a significant challenge to myocardial well being.
What is the anesthesia technique that allows for the most accurate assessment of neuro function during the surgery?
Regional anesthesia.
What is better for a CAE...general anesthesia or regional anesthesia?
Neither.

Lewis and Warlow multicenter study – “no difference in outcome between general and local anesthesia for CEA”.
If you choose GETA for your CAE what additional monitoring do you need?
A way to measure cerebral blood fllow.
Advantages and Disadvantages of using GETA for CAE....

What are some important considerations:
Major advantages:
* Ability to offer ideal operating conditions for the surgical team
* Many surgeons refuse to operate under regional anesthesia
* Patients also express uneasiness about being awake
* Decrease CMRO2 (decr O2 demand)

Major disadvantage
* Inability to provide precise monitoring of cerebral function

Considerations
* Preserve cerebral circulation and oxygen delivery at all stages of surgery
* Provide cerebral protection (gases do this)
* Prevent myocardial ischemia (avoid HTN and tachycardia)
* Prevent patients from coughing and straining with extubation
Advantages and Disadvantages of using Regional Anesthesia for CAE:
Advantages
* Allows for proper intraop monitoring of neuro function during the cross clamp stage to assess for cerebral ischemia!! :)
* Awake patient offers ideal conditions for focal neurologic assessment
* Regional anesthetic technique avoids unnecessary ventilator support with all the associated potential complications

DISADVANTAGES
* Can wear off with long surgeries.
* Pt can get uncomfortable.
* Pt can move.
* Lidocaine in surgical field will mess up surgical field.
* MIght not have adequate pain control.
* No access to airway if the stop breathing....head is turned and you can't intubate that way.
EVERY CAE pt gets what type of monitoring?
* Precordial stethescope
* Temperature probe
* BP cuff
* EtCO2 monitoring
* Intra-arterial catheter: art line.
* EKG leads II and V5
What is better for high risk CAE pts...a swan or a central line?
A swan.
What is the gold standard for cerebral ischemia monitoring for a CAE?
an EEG.

Problem is...it's not practical. Electrodes can intefere with the surgical field and you need a technician to read it...and you don't always have that.
What is the most commonly used and practical method for monitoring for cerebral ischemia?
Cerebral oximetry
What are the downsides to using a transcranial doppler to monitor for cerebral ischemia?
Pt has to wear a headband with transducers. This can interfere with the surgical field. Plus you need a technician to read it.
T/F

an increase in your pulmonary artery wedge pressure means that you are having myocardial ischemia.
FALSE

Increase in PCWP is not a sensitive indicator of myocardial ischemia
If using a swan during a CAE, where must it be placed?
Cannot use the IJ. Must use subclavian or the IJ On the opposite side. Subclavian increases teh risk of pneumothorax.
A transcranial doppler measures the velocity of blood flow where?

What is it useful for?

What is NOT useful for?
In the middle cerebral arteries on the ipsilateral side.
(These are the ones that emerge from the internal carotid arteries).

It is useful for detecting intraop cerebral emboli!!

Low predictive valve for neurologic defects during cross-clamp.
Cerebral Oximetry measures O2 sats where?
What is them mechanism of measurement?
What are it's advantages?
REGIONALLY: Can tell you the O2 sat in a specific part of the brain at the microvascular level.
* Reflects regional cerebral metabolism and balance of local cerebral oxygen supply / demand

Uses infrared spectroscopy: Based on the beer lambert law.

ADVANTAGES
* Provides CONTINOUS, noninvasive monitoring of cerebral oxygenation.
* is a SENSITIVE measure for cerebral hypoxia/ ischemia. (can be used during cross clamping).
What is the most sensitive measure of cerebral ischemia?
An awake patient.
Most strokes d/t a CAE occur when? What caues them?
Most strokes occur following surgery and are likely related to thromboembolic phenomena
An EEG measures ______. What things can effect EEG readings??
An EEG measures electrical activity in the cerebal cortex. 2 or 4 channel recordings to determine right and left symmetry during cross-clamping.

Can be affected by:
* Hypothermia
* Hypocarbia
* Hypoxemia
* Deep Anesthesia

May give false negatives.
What is INVOS?
First Generation monitoring of cerebral oxygen saturation.

Uses 2 waveslengths of infrared light (just like a pulse ox) from light emitting diodes.

Two channels are present for bilateral brain monitoring. ...calculates and displays the value of regional cerebral oxygen saturation.

Provides only TREND monitoring or REGIONAL O2 sat of brain.

* Intervention should ONLY be based on changes in TRENDS...ie..changes in rSO2 from the initial baseline value.
INVOS values should be kept at ___ to ___% of baseline.
INVOS values should be kept at 20% to 25% of baseline.

If oximetry value falls below 20%, means poor blood flow to that region of the brain.
What is Fore-Sight (CAS)
Second Generation Cerebral Oximetry Monitor.

* Near-infrared spectometer that measures ABSOLUTE cerebral tissue oxygen saturation.

* 2 channels for bilateral brain monitoring

* Left and right hemisphere are measured and graphed. Uses 4 precise wavelengths to determine ABSOLUTE rSO2 in each hemisphere.

* Get a baseline and look for changes in TRENDS from baseline.

* Gives a ratio of arterial to venous blood as well.
What is the newest and best monitor for cerebral oximetry?
Equanox rSO2
Equanox rSO2
Newest and Best cerebral oximeter.

* Gives immediate and constant beat-to-beat monitoring.

*Will alarm when sats drop < 20-25% of baseline on either side.
Your cerebral oximetry monitor tells you that blood flow/oxygenation has dropped > 20% on one side of the brain, what do you do?
1) Increase MAP with pressors
2) Hypoventilate the pt (VD's the brain).
3) Tell the surgeon ASAP...he might need to place a shunt.
What induction agents can you use for a carotid endarterectomy?
Propofol : GIVE SLOW!!

Etomidate: No cardio effects!

Sodium Pentothal

Lidocaine IV or LTA to decrease the response to laryngoscopy and intubation.

Beta blocker for HTN, tachycardia

Nitrous Oxide and Narcotics
What muscle relaxants are good for a carotid endarterectomy? Which ones are not?
Hemodynamically stable ones only...ie avoid ones that cause histamine release...which can cause HOTN.

Preferred:
Vecuronium
Rocuronium
What narcotics are used for a carotid endarterectomy? Why?
To decrease the SNS response to intubation. Hold off on emergence to allow for a neuro exam.

* Fentanyl – 1 – 5 ug/kg (hold off on emergence)

* Remifentanil – 0.05 – 0.2 ug/kg/min continuous infusion

* Sufentanil – 10 – 30 ug
How do volatile agents effect anesthesia/ cerebral status of pt getting a CAE?
* Have a neuroprotective effect via sedation.

* Can decrease autoregulation of the brain.

* Give with nitrous oxide to decr the amt given.

* Use low doses.... .5-1 MAC
Pluses and minuses to using ETT for airway for CAE
PROS:
* Ensures adequate airway protection
* Allows for mechanical ventilation

CONS
* Can induce tachycardia and HTN with intubation
* Coughing and straining can occur during extubation.
Pros and Cons for using an LMA for airway for CAE
PROS
* Helps avoid sympathetic response associated with ETT placement.

CONS
* Do not provide complete protection of the airway

* Can present a problem for alveolar ventilation sometimes.
BP during maintenance of a CAE should be maintained at what level?
Maintain a HIGH BP w/n 20% of baseline.

Use phenylephrine (neo) to do this.
Although you want BP elevated 20% of baseline...how can you avoid extreme HTN during sx?
Nitroglycerin drip. (CA dilation!!) :)

Nicardipine, Clevidipine(Cleviprex) gtt, esmolol.
What are your goals for CO2 level during a CAE?
Normocapnia 35-40mmHg.

Hypocarbia will cause CEREBRAL ISCHEMIA!

Hypercarbia will cause cerebral steal.
During a CAE, surgeon is dissecting the plaque around the carotid sinus. You get sudden bradycardia. Why did this happen and what do you do?
Arterial baroreflex was stimulated by stimulation of the baroreceptors in the carotid sinus.

1) Tell surgeon to STOP
2) Give Ephedrine
3) Give Robinul (anticholinergic). Don't use atropine because it can cause too much tachycardia...these pts may also have atherosclerosis of Coronary arteries..you dont' wnat to increase their MVO2!
4) Can also inject 1-2 mL of Lidocaine into the site.
During a CAE, you do not want Carotid Artery Stump Pressure to fall below what?
50 mmHg

If it goes below this you must shunt!!
Explain Carotid Artery Stump Pressure Monitoring
This is a method of predicting intraop ISCHEMIA by looking at the back-pressure from the Internal Carotid Artery.

Method:
--> Clamp the proximal common carotid and external carotid artery. Surgeon inserts a gelco needle into the internal carotid artery that is hooked to an extension tubing and a transducer. Don't let the pressure fall below 50 mmHg.

RISKS
* May break off plaque and cause an embolism.
* Clamping can also damage vessels.
* Small risk of bleeding.
When must you heparinize your pt during a CAE? How much heparin should you give?

What is your goal ACT?
Heparinize with 70-100 units/kg 2-3 min BEFORE cross clamping.

Goal ACT is > 250 sec
What important considerations must you make regarding cross clamping?
* Heparinize with 70-100 units/kg 2-3 min BEFORE cross clamping.
* Goal is to minimize clamp time if not shunting. Document the time that the clamp is placed and released.
T/F Shunting during a CAE guarantees protection against a stroke.
FALSE

Can break off plaque and cause a stroke. Can still have a stoke from hypoperfusion.
Pros and Cons to shunting
PROS
* Improves cerebral O2 delivery
* Provides for more cerebral protection

CONS
* Does not guarantee protection against a stroke. Cross clamping can cause plaque embolization, air bubbles, or hypoperfusion.
* Increase total surgical time.
* Operative Site interference
* Can have a distal intimal flap and bleeding.
Should you or should you not give Protamine sulfate after a CAE to reverse the heparin?
Depends on the surgeon.
You are about to emerge a pt after a CAE...you just gave protamine sulfate to reverse the heparinization upon surgeon's request. Suddenly you see your sats drop and you get HOTN. What do you do??
This is a side effect of the Protamine sulfate. (HOTN and anaphylactic rxn).

Give heparin to reverse it.
You have are emerging a pt after a CAE...what evaluations should you do before you extubate (to assess nerve function?)
Hypoglossal Nerve: Ask pt to stick out tongue...if it protrudes to one side..damage.

Glossopharyngeal and Vagus Nerve: Normal Gag reflex. Pt can swallow.

Accessory Nerve: Pt can turn head from side to side and shrug shoulders..look for assymetry b/n shoulders.

Facial Nerve: Ask pt to smile

Laryngeal Nerves..put in boogie and extubate...see if the cords close.
You are emerging your pt after a CAE....what do you need to have on hand?
Goal is to minimize HTN, tachycardia to pvt MI, ischemia, stroke, bleeding, etc.

* Give IV Lidocaine to pvt coughing and straining. ...don't want incision to come open.

You need to have IN LINE:
* Nicardipine or Labetalol for HTN
Should you extubate your CAE pt deep?
PROS: Will pvt coughing and straining

CONS: Will have to reintubate if nerve assessment shows that pt has damage.
Why can you not so a CAE on both carotid arteries in one surgery?
Surgery on the carotid artery disrupts the Carotid Sinuses and Bodies. If you did both at the same time your pt would have essentially NO baroreceptor or chemoreceptor function post op and could have major hemodynamic and respiratory complications.
Post op from a CAE your pt had some HTN, then suddenly has trouble breathing and you see tracheal deviation...what is going on?
1) Possible hematoma from bleeding incision ...pushes trachea over.

HTN caused by dysrupted baroreceptors.
Your pt was alert and oriented upon emergence/ post extubation after a CAE. Post op, your pt suddenly experiences a neuro deficits ...there is no noticeable bleeding from anywhere...what is going on?
Pt could be having an embolism


if this happened weeks or months later it coudl be an intimal flap.
Post-op your pt experiences apnea despite hypoxia in the PACU after a CAE. What could be going on?

What can you do to pvt the hypoxia?
Carotid body dysfunction d/t manipulation in surgery. ...no ventilatory response to hypercarbia or hypoxia.

ALWAYS HAVE YOUR PT ON O2 POST-OP AND TO PACU AFTER AN CAE!!!!!!!!!
What can cause HOTN postop after a CAE?
Carotid sinus dysfunciton (baroreceptors)

Myocardial depressant effects of drugs

Hypovolemia (blood loss in sx).
What can cause HTN post op after a CAE?

What other problems can this cause in your patient?
* Carotid Sinus dysfunction (baroreceptors)

Can cause:
* Bleeding/ hematoma at incision
* Increased MVO2 - potential myocardial ischemia in CAD pts.
* Intracerebral hemmorhage
* Increased ICP (when brain's autoreg is gone).
What are three types of Regional Anesthesia Techniques for CAE?
1) Deep cervical plexus block (C2-C4) (anterior roots)
2) Superficial cervical plexus block (C2-C4)
3) Cervical epidural anesthesia
Your pt needs a CAE but has a tracheal shift from a hematoma (but is stable)...what anesthesia will you use?
Regional..cannot intubate.


This was on kristi's pp slide but makes no sense...you would not do a regional when you have a resp emergency?
Deep Cervical Plexus Block

What is it:
What are it's risks?
Regional Technique for CAE.
--> Anesthetizes the cervical plexus that is formed from C2-C4 anterior rami of the IPSILATERAL spinal roots.

RISKS
-->Proximity of injection to structures such as:
* Carotid artery
* Internal jugular vein
* Vertebral arteries
* Spinal cord
* Phrenic nerve
-->Inadvertent intravascular or intrathecal injection and paralysis of the IPSILATERAL diaphragm can occur!!!
Superficial Cervical Plexus Block

What is it?
What are it's risks?
Regional Anesthesia technique for CAE

--> Anesthetizes the C2-C4 branches responsible for SENSATION of the SUPERFICIAL NECK TISSUES.
--> This block is done by infiltrating LA along the posterior boarder of the SCM.
--> NO difference from a deep cervical plexus block in operative conditions or the need for supplemental intraop anesthesia.

RISKS
* Inadvertent intravascular injection in the external jugular vein
* Phrenic nerve blockade occurs rarely
Neurologic defects postop after a CAE are due to...
Embolism
Reperfusion Injuries
Intracranial Hemorrhage
Anesthetic Effects
Respiratory Insufficiency post-op after a CAE can be caused by...
Vocal cord paralysis due to traction of laryngeal nerves

Wound hematoma ( leading cause!!)

Carotid body dysfunction
What is the leading cause of respiratory insufficiency postoop from a CAE?
Wound hematoma...causes a tracheal deviation.
Is carotid stenting more beneficial than a CAE?
No! It has more risks of embolism. Only do it if the pt cannot have a CAE.
What are some indications for Carotid Artery Stenting?

What are the risks/ benefits of stenting instead of CAE?
INDICATIONS FOR STENTING:
* Inoperable Stenosis located above C2..near the cranium.
* Comorbidities that contraindicate surgery.

BENEFITS
* Minimal sedation with local anesthesia...allows for cerebral monitoring.

RISKS
* Cerebral emboli major risk for ischemia!!! ( not getting rid of the plaque...could dislodge it)
* Femoral artery damage
Describe monitoring for Carotid STents
Done in “Hybrid rooms” – incorporate x-rays and sx at the same time. Used for percutaneous valve replacement sx. Like a cath lab and xray lab and OR.

Monitoring with transcranial dopplers
What are some comobidities with PVD?
CAD
DM – 3x increased
Hypertension
Smoking
Hyperlipidemia
When do you use thrombolytic therapy to tx PVD?
For acute occlusion.
What is the first clinical manifestation of PVD.
Claudication: painful, aching, cramping, uncomfortable, or tired feeling in the legs that occurs during walking and is relieved by rest.

* Happens with PVD...can lead to infection and limb loss

The best tx is exercise..which helps you develop collateral circulation.
What is the difference b/n intermediate and critical limb ischemia/claudication?
Intermediate is in vessels that are not that big of a deal. Ex: A ruptured popliteal anneurysm will heal over with no bad effects.

Critical: Occurs in vessels that are critical to the leg. Large vessels can aneurysm and rupture.
How can you treat claudication?
--> Cessation of smoking
--> Exercise
--> Statin Therapy – improvement in intermittent claudication
--> BP control – ACE / ARBs
--> Glucose control – Hgb A1C levels ↑ → ↑ PVD
--> Antiplatelet therapy – ASA + clopidogrel
--> Phosphodiesterase inhibitors – cilastozol (VD the vessels..decr tubulent flow).
--> Homeopathic treatment - ginko biloba; chelation therapy
Surgical indications PVD
* Pain at rest
* Ischemic extremity..may need an embolectomy or thrombectomy
* Gangrenous extremity
Where do you access pt for a carotid stent?
femoral artery
Explain bypass surgery for PVD.
Bypass of a peripheral artery will require a prosthetic or a vein graft. The veins are taken from the SAPHENOUS VEIN. The valves must be removed...they have a device that runs through the veins and cuts the valves out. Infra-inguinal incision to target vessel.

* Prosthetic grafts have a shorter life-span than vein grafts.
Preop labs for a PVD surgery
PT
INR
PTT
CBC
Extra monitoring during PVD sx depends on
associated comorbidities.
Advantages and Disadvantages of Regional Anesthesia for PVD bypass
ADVANTAGES
* Effective blockade of stress response
* Patient as monitor (dyspnea, angina)
* Improved graft blood flow
* Possible prevention of chronic syndrome (Reflex Sympathetic Dystrophy)
* Possible improved cardiopulmonary morbidity

DISADVANTAGES
* May be inadequate for the surgery
* Patient discomfort during long cases
* Sympathectomy requires volume loading
* Respiratory depression from sedation or high level of blockade
* Rare neurologic sequel
* Precludes thrombolytic therapy?
What is Chronic Syndrome with PVD sx? (RSD)?
RSD is an older term used to describe one form of Complex Regional Pain Syndrome (CRPS). Both RSD and CRPS are nerve disorders characterized by chronic severe burning pain, pathological changes in bone and skin, excessive sweating, tissue swelling and extreme sensitivity to touch. RSD is sometimes called Type I CRPS, which is triggered by tissue injury where there is no underlying nerve injury, RSD is unique in that it affects the nerves, skin, muscles, blood vessels and bones at the same time.

continuous pain that gets worse instead of better.
If your pt is on ASA and plavix what does that mean about yoru anesthesia?
No regionals. Must do GETA.
Advantages and Disadvantages of General Anesthesia
ADVANTAGES
* Controlled airway
* Thrombolytic Therapy okay
* Hemodynamics easily controlled reliable
* Patient comfort ensured for long cases

DISADVANTAGES
* Hydernamic state after sx...stage II and ETT on emergence.
* Cat flux.
Describe anticoagulation technique for PVD sx.
* Give 5000-10,000 units (.5-1 mg/kg) IV prior to clamping.
* Redose every 45 min in normothermic conditions (the t1/2 of heparin is 45 min).
* For regional
---> Delay heparin admin for 1 hr after needle placement.
---> Indwelling catheters should be removed 2-4 hrs after last dose of heparin.
What is the most stimulating part of PVD sx?
Tunnelling through tissues to place the vein.
Preop for a PVD pt is the same as for a ____ Pt.
Preop for a PVD pt is the same as for a CAD Pt.
The major cause of morbidity during PVD sx relates to what?
Myocardial Infarction.