Mod11: Anesthetic Considerations for Radiology & Radiation Therapy

Question 1

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why must caution be used with IV contrast agents during Radiology & Radiation Therapy procedures?

Answer 1

It’s not uncommon to see people with IV contrats allergies

Question 2

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is allergy to IV contrast mostly associated with older agents?

Answer 2

Older ionized contrast media were hyperosmolar and toxic

_{Pts who received IV contrast in the 70s or 80s and had a reaction, will have it documented in their chart as an “allergy”.}

_{These pts may benefit from Benadryl or a steroid pretreatment}

_{If history of Anaphylactic reaction or a more recent history of allergic raction, talk to the physician about maybe trying out something else besides IV contrast (e.g., cancelling the procedure, non using contrast at all)}

Question 3

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How do new IV contrast agents differ from the older agents?

Answer 3

Newer non-ionized contrast media have lower osmolality and improved side-effects

Question 4

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Predisposing factors to adverse reactions from contrast media include a history of:

Answer 4

Bronchospasm - Allergy - Cardiac disease

Hypovolemia - Hematologic disease - Renal dysfunction

Extremes of age - Anxiety

Medications _{(Beta-blockers, aspirin, and NSAIDs)}

Question 5

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Bronchospasm a Predisposing factor to adverse reactions from contrast media?

Answer 5

….

Question 6

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Allergy a Predisposing factor to adverse reactions from contrast media?

Answer 6

…

Question 7

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Cardiac disease a Predisposing factor to adverse reactions from contrast media?

Answer 7

…

Question 8

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Hypovolemia a Predisposing factor to adverse reactions from contrast media?

Answer 8

…

Question 9

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Hematologic disease a Predisposing factor to adverse reactions from contrast media?

Answer 9

…

Question 10

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Renal dysfunction a Predisposing factor to adverse reactions from contrast media?

Answer 10

…

Question 11

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is Extremes of age a Predisposing factor to adverse reactions from contrast media?

Answer 11

….

Question 12

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of Anxiety a Predisposing factor to adverse reactions from contrast media?

Answer 12

…

Question 13

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Why is a history of using some Medications _{(Beta-blockers, aspirin, and NSAIDs)} a Predisposing factor to adverse reactions from contrast media?

Answer 13

…

Question 14

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How does a mild reaction to IV contrast agents manifest?

Answer 14

Nausea - Perception of warmth - Headache

Itchy rash - Mild urticaria

_{Not really considered a reaction; more of a side effect from the contrast}

Question 15

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How does a Severe reaction to IV contrast agents manifest?

Answer 15

Arrhythmias - Bronchospasm - Dyspnea - Chest pain

Feeling faint - Rigors - Vomiting - renal failure

Severe urticaria

Question 16

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How does a Life-threatening reaction to IV contrast agents manifest?

Answer 16

Arrhythmias - Cardiac arrest

Glottic edema/bronchospasm - Pulmonary edema

Seizures/unconsciousness.

Question 17

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How are reactions to IV contrast treated?

Answer 17

O2 - Bronchodilators - Epinephrine

Corticosteroids - Antihistamines - Intubation

Circulatory support with IV fluids/pressors

_{Also refer to lecture on Anaphylaxis reaction}

Question 18

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Contrast-induced nephropathy accounts for what % of hospital-acquired renal failure

Answer 18

10%

Question 19

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Contrast-induced nephropathy is more common in which clinical conditions?

Answer 19

Renal insufficiency

DM

NSAIDs

Question 20

_{Anesthetic Considerations for Radiology & Radiation Therapy}

How could the risk of Contrast-induced nephropathy be reduced in susceptible patients?

Answer 20

Adequate hydration

Monitoring U/O

Low osmolarity contrast media

Administer NaHCO3 IV infusion 1hr before contrast administration

Question 21

_{Anesthetic Considerations for Radiology & Radiation Therapy}

Radiation exposure is a unique hazard. What could it lead to?

Answer 21

Leukemia and fetal abnormalities

Question 22

_{Anesth. Considerations for Radiology & Radiation Therapy - Radiation exposure}

Why are providers required to wear dosimeters?

Answer 22

Measure amount of radition providers are exposed to

Turned back in monthly

Allows to identify locations with excessive emissions

Allows for reassignment of providers with elevated readings

Question 23

_{Anesth. Considerations for Radiology & Radiation Therapy - Radiation exposure}

What is the maximum amount of radiation a provider should be exposed annually?

Answer 23

50 mSv or 5,000 milirams

Question 24

_{Anesth. Considerations for Radiology & Radiation Therapy - Radiation exposure}

Which equipments should be used for the purpose of protection from ionizing radiation each time radition exposure is and anticipate?

Answer 24

Lead apron _{(front and back)}

Protective goggles

Thyroid shield

Leaded glass screens

Question 25

_{Anesth. Considerations for Radiology & Radiation Therapy - Radiation exposure}

Which eye condition could result from exposure to radition overtime if Protective goggles are not used?

Answer 25

Cataract

Question 26

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

What is the typical access for Angiography (Spinal/Cerebral)?

Answer 26

Femoral artery

Question 27

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

In which cases would the Femoral vein be accessed for Angiography?

Answer 27

During AVM imaging or

Dual Venous abnormalities

Question 28

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

Since Diagnostic angiography is only associated with minimal discomfort, what are anesthetic requirements?

Answer 28

Local with or w/o light sedation
by non anesthesia providers

Question 29

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

What are the anesthetic requirements for angiograpgy procedure in pts unable to tolerate procedure (neuro disorder, severe pain, lengthy procedure)?

Answer 29

Deep sedation

General anesthesia

_{Anesthesia provider must be present}

Question 30

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

What physiological changes accompany injection of IV contrast dye?

Answer 30

Discomfort, burning, pruritus around face

^{(often masked by anesthesia)}

Hypotension & bradycardia

^{(if reaction)}

Question 31

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

During angiography, when pt is placed on moving gantry, and the C-arm is used to track catheter from groin into cerebral vessels, anesthesia provider should carefully monitor extensions cords/tubing to prevent dislodgement of which equipments?

Answer 31

Breathing circuits

IV tubing

Monitors

Caution injury occurring to pt from radiology equipment

Question 32

_{Anesthesia for Radiology & Radiation Therapy - Angiography (Spinal/Cerebral)}

True or False: EKG electrodes may interfere with imaging during spinal angiography.

Answer 32

True

Question 33

_{Anesthesia for Radiology & Radiation Therapy}

Interventional Neuroradiology is used for the the Endovascular treatment of which neurosurgical conditions?

Answer 33

Intracranial aneurysms with detachable coils

Arteriovenous malformations

Question 34

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What size sheath is used to gain Arterial access via the femoral artery during Interventional Neuroradiology?

Answer 34

6 - 7 French sheath

Question 35

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

Besides Femoral artery access, what other access can be used for interventional Neuroradiology procedures?

Answer 35

Carotid or axillary artery

_{Possible but rare}

Question 36

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What happens as the catheter is advanced?

Answer 36

Guide catheter is advanced through sheath

Road mapping technique employed

Boluses of IV contrast dye injected to outline vascular anatomy

Guide advancement of microcatheters for placement of embolic materials into aneurysm or feeding vessels of AVM

Question 37

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

When and how long is anticoagualtion required with Interventional Neuroradiology procedures?

Answer 37

During & 24hrs after procedure

Question 38

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

When Heparin is used after the procedure, what’s the protocol?

Answer 38

Heparin 3000-5000 units IV initial bolus, and

1000 units/hr to maintain ACT at 2.5 times pt’s baseline

Question 39

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What are advantages of Interventional Neuroradiology procedures?

Answer 39

Avoids need for surgical craniotomy

Reduces cognitive impairment and frontotemporal brain damage

Reduces the risk of spontaneous recurrent hemorrhage following subarachnoid hemorrhage

Considered upstream surgical interventions vs a downstream surgical interventions which are interventions after the event already happened

Question 40

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What are complications of Interventional Neuroradiology procedures?

Answer 40

Hematoma/hemorrhage form femoral artery puncture

Air embolism via femoral artery sheath

Bradycardia/transient asystole during carotid artery stent placement

Pulmonary embolism (acrylic glue used - smells like garlic)

Intracranial hemorrhage - Thromboembolic stroke

Question 41

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What is the most likely cause of Bradycardia/transient asystole during Interventional Neuroradiology procedures?

Answer 41

Vagal stimulation from carotid artery stent placement

Question 42

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

What are initial resuscitation intervevention in the Acute management of neurologic complications?

^{(What would you do if you notice a change when the pt is under light anesthesia or when she is waking up?)}

Answer 42

Communicate with radiologists

Call for assistance

Secure airway & hyperventilate with 100% O2

Determine if problem hemorrhagic or occlusive

Question 43

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

How do you treat a Hemorrhagic complication during an Interventional Neuroradiology procedure?

Answer 43

Immediate heparin reversal

^{(1mg protamine for each 100U heparin given)}

Low normal pressure

Question 44

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

How do you treat a Occlusive complication during an Interventional Neuroradiology procedure?

Answer 44

Deliberate hypertension titrated to neurologic examination

Angiography, or

Physiologic imaging studies (TCD, CBF)

Question 45

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

How much Protamine is given per units of Heparin for Immediate heparin reversal during an Interventional Neuroradiology?

Answer 45

1mg Protamine for each 100U heparin given

Question 46

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

While waiting for definitive tx of acute complications during Interventional Neuroradiology procedure, what could be done in the interim?

Answer 46

Head up 15˚ in neutral position

Titrate ventilation to a PaCO2 of 26-28mmHg

Mannitol 0.5mg, rapid IV

Anticonvulsants

^{Dilantin 50mg/min (slowly)}

^{Phenobarbital}

Titrate STP infusion to EEG burst suppression

Hypothermia (allow temp to rapidly ↓ to 33-34˚C)

Consider dexamethasone 10mg

Question 47

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, how should the head be positionned?

Answer 47

Head up 15˚ in neutral position

Question 48

^{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts,

Titrate ventilation to a PaCO2 of

Answer 48

26-28mmHg

Question 49

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, what dose of Mannitol would you administer?

Answer 49

0.5mg, rapid IV

Question 50

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, which anticonvulsants would administer?

Answer 50

Dilantin 50mg/min (slowly)

Phenobarbital

Question 51

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, what would you titrate STP infusion to?

Answer 51

EEG burst suppression

Question 52

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, what’s your Hypothermic goal and strategy?

Answer 52

Allow temp to rapidly ↓ to 33-34˚C

Question 53

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, which dose of dexamethasone would you administer?

Answer 53

10mg

Question 54

_{Anesthesia for Radiology & Radiation Therapy - Interventional Neuroradiology}

In the acute management of neurologic complications during Interventional Neuroradiology procedures and as part of further resuscitation efforts, why would you administer steroids?

Answer 54

To decrease swelling