Pertaining to the Oculocardiac reflex:

True or False?:

1) Traction on the extraocular muscle or pressure on the globe can elicit a wide variety of cardiac dysrhythmias.

2) The afferent pathway of this reflex includes the facial never while the efferent pathway is the vagus nerve.

3) Most common in The elderly

4) Can occur during any type of eye surgery

5) If this reflex is elicited while the pt is awake they may become somnolent or c/o nausea

6) Epinepherine and neosynepherine given prior to the stimulating event is of benefit to reduce the possibility of eliciting the response.

7) Stacey's favorite Block- the retrobulbar regional block- increases the incidence of the oculocardiac reflex.

1) True: to include- bradycardia, ventricular ectopy, sinus arrest, or ventricular fib.

2) False:  Afferent pathway is the trigeminal nerve, efferent reflex pathway is the vagus nerve

3) False:  Children.  But can be evoked at all ages. 

4) True

5) True

6) False: Atropine or Glycopyrrolate.  IV is better than IM

7) False: it reduces the incidence.  However performing the block can elicit the response.  So how gay.

What are the 6 things you could do (only if you wanted) if your pt. was having symptoms from an ellicited oculocardiac reflex?

ie: How would you manage it?

1) Notify the Surgeon to "Stand Down!"

2) Confirm adequate ventilation

3) IV Atropine 10mcg/ kg

4) Epinepherine if you are having hemodynamic problems

5)  CPR  (holy shit are you kidding me?)

6) Infiltration of the rectus muscle with local anesthetic

Fill in the blanks:

The occulocardiac reflex eventually _____1_____ itself with repeated traction on the _____2______ muscles.

1) Fatigues

2) Extraocular

1) What is injected during vitreous surgery to flatten a detached retina?

2) How long does this substance stay in place?

3) What should we avoid using as anesthetists when this substance is in place?  Why?

1) Air Bubbles OR a gas called sulfa hexafluouride

2) Air bubbles stay in place for approx. 5 days

sulfa hexafluoride stays in place for 10 days

3) Nitrous oxide use should be questioned.  If used should be d/c'd 15 minutes prior to injection of air bubble or closure of globe.

1) What is a pathological increase in IOP caused by and increased resistance to outflow of aqueous humor?

2) How is this caused?  What happens to the trabecular network with Glaucoma?

3) What are the 2 types?

1) Glaucoma-

2) Glaucoma is caused by a resistance to the outflow of aqueous humor.  (Duh-see #1)  The trabecular network thickens with Glaucoma.  This endothelial thickening resists the outflow of aqueous humor thus increasing IOP.

3) Open and closed angle glaucoma

1) What happens in closed angle glaucoma?

2) What should we avoid with closed angle glaucoma?

1) The iris bulges forward blocking the access of aqueous humor to the trabecular network.  This can occur with pupillary dilation or with an acutely swollen lens. 

2) If the patient has closed angle glaucoma, we should avoid drugs or conditions where the pupil dilates.

Note:  Gayle has something screwy on slide 33 that I am trying to get clarified. 

But here is the statement:

When discussing ophthalmic drugs, it is important to not confuse the following concepts:

When the muscles contract, the pupil dilates; when the muscles relax, the pupil constricts. 

Hmmmmmm- take it for what it is.  Next slide

1) I'm a bitchin' drug that has similar opthalmic effects to phenylephrine, but I have to sit the bench a lot. (ie: I'm used more rarely)

2) Give me the 2 drugs used in opthamlmic surgery that are nonselective beta antagonists often used in glaucoma. 

3) For question #2 above: What types of pts do we need to be careful with when using these drugs.  What can happen? 

4) For questions 2 and 3 above:  These drugs can cause a bradycardia that is resistant to a certain drug.  Which drug is that? 

5) What drug is sometimes used to produce miosis? 

6)What is the name and type of drug that when used can prolong the action of succs?  How Much longer will the duration of succs last with this drug in a pts system?   How long does this drug stay in a pts system?

7) What type of drug (and give an example) interferes with the sodium pump mechanism responsible for making aqueous humor?

1) epinepherine

2) Timolol and betaxolol

3) Asthmatics, Pts with a hx of CHF, conduction defects, or bradycardia

4) Atropine

5) Acetylcholine

6) Echothiophate, ananticholinesterase drug.

Succs will last up to 30 minutes with this drug.  Echothiophate stay in a pts system up to 3 weeks

7) Carbonic anyhadrase inhibitors (like acetazolamide)

All anesthetic agents reduce IOP except 2.

Which are they?

1) Ketamine

2) Etomidate

True or false:

1) the choice between local, regional, or general anesthesia is made between the surgeon, pt, and anesthesia provider.

2) Regional anesthesia is often chosen for the uncooperative pt. 

3) Pts coexisting conditions are less of an issue with eyeball surgery

4) Pts are pretty calm going into eyeball surgery

5) It's a good idea to have ACLS equipment available when performing regional anesthesia.

1) true

2) False.  General is preferred

3) False.  Coexisting conditions need to be considered.  (Yes, I consider you a fatty- Game on)

4) False.  Generally anxious.  Consider Anxiolysis

5) If you answered false to this you may never touch me or any of my family members.

1) Eye will be patched upon wake up

2) Avoid coughing and bucking or Light anesthesia

3) Lidocaine 1 to 1.5 mg/kg iv 1-2 minutes before DVL or prior to exubation

4) PONV is particularly bad in Eyeball surgery-therefore address it. 

5) Deep extubation if not aspiration risk

(There are others- but they are common sense anesthesia issues)

1) What is the most common associated risk with Open globe injuries? 

2) What do we need to avoid in this situation?

3) What do we need to consider regarding the use of narcotics in this situation? 

4) What type of anesthesia should not be used in this situation? 

5) When pre-oxygenating to remove the hot-poker- in the eyeball- what do we need to avoid?

1) full stomach.  A decision has to be made weighing the risk of aspiration with that of extrusion of the globe contents. 

2) Anything that increases IOP including poor cricoid pressure (it can prevent venous drainage from the head and eye)

3) Narcs cause N/V.  Use N/V prophylaxis and aspiration prophylaxis like: reglan, non-particulate anatcids, zantac

4)Regional

5) Don't put pressure on the globe.

Special Considerations with open globe injuries:

1) Can succs be used? 

2) How can we reduce the theoretical rise in IOP with Succs?

3) What is an alternative to rapid sequence with succs that we can use?

1) My take away is this:  Maybe. "Authors are constantly debating whether succs can be used safely"   If the injury is permanent and the eye can't be saved- you can, but you better document bitch. 

2) Anal beads.... Just kidding.  Give a defasiculating dose of rocuronium. 

3) Use rocuronium- with a priming dose.  It is the fastest NDMR that we have.