Additive Effects/Misc.

Question 1

What drug class does methylene blue fall under?

Answer 1

potent monoamine oxidase inhibitor (MAOI)

Question 2

What agents does methylene blue interact with?

Answer 2

• selective and nonselective serotonin reuptake inhibitors (SSI/SSRI)
• serotonin-norepinephrine (SNRI)

Question 3

What side effects may occur with methylene blude administration?

Answer 3

• severe, potentially fatal serotonin toxicity
• blue arm syndrome!!!

Question 4

What are signs and symptoms of serotonin toxicity?

Answer 4

• CNS excitation: hyper-reflexia, myoclonus, tremors, rigidity, resp failure (severe)
• Mental state: insomnia, anxiety, agitation, confusion, coma (severe)
• autonomic excitation: tachycardia, HTN, nausea, diaphoresis, flushing, mydriasis, hyperthermia (severe)

Question 5

What signs and symptoms can we see with serotinin syndrome using the acronym HARMFUL?

Answer 5

Hyperthermia
Anticognitive
Reflexive
Myoclonus
Fast heartrate
Unconsciousness
Loss of GI control (diarrhea)

Question 6

How can a patient get serotonin toxicity?

Answer 6

from SSRI overdose, or MAOI and SSRI combination

Question 7

Methylene blue can be considered to cause reverse __________

Answer 7

reverse hemoglobinemia

Question 8

What is fluorescein dye used for?

Answer 8

• to visualize ureters during cystoscopy
• intraoperative urologic dye marker

Question 9

What precautions do we have wtih fluorescein dye?

Answer 9

• bronchial asthma
• avoid extravasation

Question 10

Typical fluorecein dye dosing

Answer 10

50-100 mgIV (100 mg/ml)

Question 11

Fluorescin onset

Answer 11

usually works within 5 min

Question 12

What is Indigo Carmine and what is it used for?

Answer 12

inactive blue dye given IV during urologic and gynecologic procedures to localize the ureteral orifices

Question 13

Indigo Carmine Dosing

Answer 13

5 ml (8 mg/cc, so 40 mg)

Question 14

What cardiovascular effects may we see with indigo carmine?

Answer 14

• hypertension due to increased PVR with increased HR
• increased BP with reflex decrease in HR
• RARE: hypotension, cardiac arrest

Question 15

What potential rare side effects may we see with indigo carmine?

Answer 15

• hypotension
• cardiac arrest
• cerebral ischemia

Question 16

What is indocyanine green (ICG) and what is it used for?

Answer 16

• green dye
• highlights structures in robotic surgery
• tissue blood flow for reconstructive/plastics surgery

Question 17

What is the peak absorption of indocyanine green (ICG)?

Answer 17

peak spectral absorption at about 800 nm

Question 18

How should ICG be prepared?

Answer 18

reconstitute wtih 10 ml sterile water

Question 19

Indocyanine green (ICG) Dosing

Answer 19

2.5 mg with 10 mlo rapid bolus flush

Question 20

When should we expect to see ICG effects?

Answer 20

takes about 30 sec to be visible