THE OPHTHALMIC PATIENT
From the 21st Annual Scientific Meeting of the Ophthalmic Anesthesia Society, September 28-30, 2007, Chicago, IL
| THE TEAM CONCEPT FOR OPHTHALMIC SURGERY —Don R. Hirschman, CRNA, MHA, ND, Adjunct Professor
of Nursing, Wichita State University, and Administrator, Associated Eye Surgery Center, Wichita, KS
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| Anesthesia care team: may include anesthesiologist, certified registered nurse anesthetist (CRNA), or combination;
speaker’s practice includes 2 CRNAs providing care for ophthalmic patients; one performs blocks in preoperative
area, other in operating room (OR) with patient during surgery; anesthesia provider part of larger team,
including receptionist, ophthalmic technicians, surgeon, janitor, microbiologist, and admitting nurse; anesthesia
provider obviously provides service, but also consumer of services (dependent on other people; should be thankful
for their services)
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| Communication: crucial to success of team and safety of production; surgery schedule subject to change (eg, patient
arrives late, order of surgeries changes); important to be flexible and communicate with other members of
team; speaker goes directly to OR to communicate any changes; surgeon must be allowed to concentrate on
“what only [he or she] can do”; everything up to and during surgery must be handled correctly by anesthesia care
team; communication key to avoiding wrong-site surgery; legendary stories about fines imposed by state of Florida
for some phase of wrong-site surgery (amputation of incorrect leg resulted in legal changes, additional training,
and more conscious effort towards identifying correct surgical site); when talking to patient, identify correct
operative site and procedure by first asking patient his or her name and then asking about procedure scheduled
for him or her that day (instead of stating what you think is patient’s name and scheduled procedure); process of
avoiding wrong-site surgery begins 1 wk before scheduled surgery
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 | Division of tasks: one anesthesia provider reviews chart, compares diagnosis with consent, and reviews surgery
schedule; other provider attempts to call patient on night before surgery (begins to establish relationship with patient)
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| Telephone call: instruct patient to take medications; also encourage patient to take anticoagulants before surgery;
discuss breakfast (speaker allows patients to eat); answer questions about anesthesia; identify operative eye (if
questions arise, mark chart and communicate possible discrepancies with staff on day of surgery; “sometimes the
surgery schedule is wrong”); good preoperative visit worth 50 mg of meperidine (Demerol); also talk about appointment
time, but never tell patient their scheduled surgery time (only an estimate); usually waiting for patient’s
eye to dilate (“you’re not waiting for us, we are waiting for you”); tell patient estimated departure time;
phone call necessary because patient usually cannot read brochures (spouse may have same problem); phone
calls time-consuming and occasionally exhausting, but “it needs to be done” (high priority)
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| Efficiency: use customized anesthesia record (spend less time writing and more time with patient); instant hand sanitizer
(eg, Purell) also saves time
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| Improving care: communicate with family physician about elevated blood pressure and blood glucose levels; reevaluate
amount of time patient arrives before surgery; steps include, 1) identify problem, 2) identify severity, 3) determine
course of action, 4) review results, 5) determine when to restudy, 6) report to board; chart review important
(“not every piece of paper belongs there”); postanesthesia care includes seeing and evaluating patient and completing
chart
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| STRABISMUS COMPLICATIONS FROM LOCAL ANESTHETICS —David L. Guyton, MD, Zanvyl Krieger Professor
of Ophthalmology and Director, Krieger Children’s Eye Center, The Wilmer Eye Institute, Johns Hopkins
University School of Medicine, Baltimore, MD
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| Identification of anesthetic myotoxicity: historical causes of vertical strabismus after cataract surgery thought
to include muscle damage from bridle suture placed beneath muscle to hold eye in place, unmasking of preexisting
superior oblique paresis, or thyroid myopathy; in late 1980s and early 1990s, retrobulbar anesthesia (primarily for
cataract surgery) suspected to be cause; study of cataract extraction and intraocular lens implantation with retrobulbar
anesthesia (2% lidocaine, 0.75% bupivacaine) showed vertical double vision day after surgery; worsened over
2 mo and developed torsional component; deviations mapped with Lancaster red-green test to identify muscles involved;
patient had typical extorsion of right eye (worsening gaze down and in), right hypotropia, esotropia (worsening
in down gaze), and torsional deviation (right eye twisted clockwise; worse in gaze down and to left);
pathognomonic of tight inferior rectus muscle often seen after retrobulbar anesthesia; speaker recessed inferior rectus
muscle 8 mm; at time of suture adjustment, muscle moved back 15 to 16 mm; lower eyelid pulled down slightly
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| Pathogenesis of restrictive muscle disorders: anesthetic myotoxicity investigated years ago by muscle physiologists,
mainly in rats; in 1985, Rainin and Carlson reported experimental injection of 0.75% bupivacaine into
human extraocular muscles at time of cataract surgery often produced postoperative strabismus; later, Carlson reported
experimental injection of bupivacaine, mepivacaine (eg, Carbocaine), and lidocaine (eg, Xylocaine) into
monkey and human extraocular muscles produced extensive degeneration of muscle fibers; regeneration of muscle
fibers occurred in muscles of young monkeys, but in elderly humans, only beginning fibrosis seen; degeneration
occurred only when anesthetic injected into muscle; bathing muscle in anesthetic agent produced only
minimal surface changes; severe pain on injection likely indicates muscle placement; in 1991, von Noorden reported
9 patients with apparent permanent paresis of vertical rectus muscle after cataract surgery; he noted that
muscle opposite permanently paretic muscle had undergone contracture (short and tight); in 1992, Grimmett and
Lambert reported cases of superior rectus tightness presumably due to temporary paresis of inferior rectus muscle;
however, results showed superior rectus muscle primarily involved; in some studies, anesthetic myotoxicity
more common after peribulbar block than retrobulbar block; gentamicin shown to cause only local fibrosis; in
1993, Esswein and von Noorden demonstrated peribulbar blocks, rather than retrobulbar blocks, more commonly
caused paresis of vertical rectus muscle after cataract surgery; cases reported by Hamilton and colleagues appeared
to result from retrobulbar anesthesia with 2% lidocaine with epinephrine (whereas other cases usually involved
mixture of bupivacaine and lidocaine); initial paresis caused by localized fibrosis from intramuscular
(IM) injection of local anesthetic; in 2007, Scott hypothesized local anesthetic does not cause pure fibrosis but
often causes hypertrophy of muscle involved; proposed using bupivacaine therapeutically to treat strabismus and
increase muscle strength
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| Speaker’s recent case: 55-yr-old with macular off-retinal detachment; underwent closed vitrectomy (with gas bubble),
no scleral buckle, under general anesthesia; no manipulation or exposure of extraocular muscles, except undiluted
retrobulbar bupivacaine 0.75% and epinephrine by blunt cannula irrigation; given as prophylaxis for
postoperative pain (however, severe pain persisted); patient had binocular diplopia (vertical, horizontal, and torsional)
after resorption of gas bubble 2 wk after surgery; 1 yr later, strabismus surgery attempted but aborted because
of inability to find lateral rectus and superior rectus muscles (excessive scar tissue); double vision worse in
down and right gaze, requiring occlusion of left eye; left eye turned upward and outward and unable to gaze
down and to right; Lancaster red-green test showed greatest deviation in down and to right gaze and extorsion of
left eye; findings at surgery showed tight left-inferior oblique muscle likely caused by anesthetic myotoxicity,
left hypertropia and extorsion and tight left lateral rectus muscle (also likely due to anesthetic myotoxicity); surgery
included left inferior-oblique denervation and extirpation (muscle sent for pathologic examination); left inferior
rectus muscle recessed with adjustable suture; scar tissue throughout orbit (seen mostly after posterior-
segment surgery; usually attributed to dissection for scleral buckle); Lancaster red-green test on next day showed
elimination of much of vertical misalignment (but patient still unable to move left eye downward), exotropia in
right gaze, esotropia in left gaze, ability to fuse in up gaze (for first time in 2 yr), and with prism on glasses, ability
to fuse in straight-ahead gaze; pathologic examination showed large variation in muscle fiber size, large hypertrophied
muscle fibers (with early splitting of individual fibers), central migration of nuclei, thickened nerve
fibers, and increase in endomysium (connective tissue); apparently, bupivacaine 0.75% causes stronger shorter
tighter muscle, vertical strabismus, and degeneration of nerve and muscle tissue; long term, bupivacaine causes
muscle fiber hypertrophy, muscle shortening, increased connective tissue or scarring, and possibly generalized
fibrosis of other tissues in orbit
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| Additional evidence: in 1991, Hamed and Mancuso showed enlargement of inferior rectus muscle after retrobulbar
injection of anesthetic agent
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| Clinical course: IM injection of anesthetic agent; degeneration of muscle fibers, temporary paresis, and diplopia after
surgery; in elderly patient, progressive segmental fibrosis and/or hypertrophy, followed by reversal of direction
and worsening of diplopia
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| Surgical correction: speaker generally uses single large recession (when single muscle involved) with adjustable
suture; others use recessed-resect procedure involving 2 muscles; both techniques satisfactory, especially when
used with adjustable sutures
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| Frequency of complications: not well known; literature estimates 1 in 200 cases after cataract surgery; 5% of
speaker’s adult strabismus cases from this cause
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| Needle: at speaker’s institution, 25-gauge needle commonly used for retrobulbar anesthesia; often pushed back over
inferior temporal orbital rim when administering anesthesia (near apex of orbit); study showed that with globe intact,
extraocular muscles (including inferior oblique and superior oblique) can all be reached from this approach
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| Retinal surgery: surgeons deny occurrence of problems with retinal reattachment surgery; postoperative strabismus
attributed to hardware placed around eye (eg, scleral buckle) rather than to local anesthesia; however, evidence
to show myotoxicty causing problems after posterior segment surgery (eg, studies have not been able to correlate
position of exoplant with direction of strabismus, increased incidence with local anesthetics, distribution [muscles
involved] same as with local anesthesia for cataract surgery, tight short muscles evident at time of strabismus surgery)
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| Hyaluronidase (eg, Hydase): presumed to protect against anesthetic myotoxicity by dispersing anesthetic agent
more quickly and decreasing onset time of akinesia, therefore requiring use of less anesthetic agent; increased myotoxicity
seen during period when hyaluronidase unavailable; hyaluronidase also available as Amphadase, Vitrase, and
Hylenex
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| Avoiding anesthetic myotoxicity: topical anesthesia with lidocaine (eg, Xylocaine) jelly; anesthetic in irrigating
solution (mixed results); administration of local anesthetic via sub-Tenon’s infusion (use began in ≈1990) using
blunt cannula (speaker uses 4% lidocaine, 2.5 mL; eliminates risk for anesthesia-induced postoperative strabismus,
except in few reported cases; significantly reduces risk for retrobulbar hemorrhage, compared to traditional retrobulbar
block)
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Suggested Reading
Capó H et al: Ipsilateral hypertropia after cataract surgery. Ophthalmology 103:721, 1996; Carlson BM et al: Extraocular
muscle regeneration in primates. Local anesthetic-induced lesions. Ophthalmology 99:582, 1992; de Faber
JT et al: Inferior rectus muscle palsy after retrobulbar anesthesia for cataract surgery. Am J Ophthalmol 112:209,
1991; Esswein MB et al: Paresis of a vertical rectus muscle after cataract extraction. Am J Ophthalmol 116:424,
1993; Hirschman DR et al: A study of the safety of continued anticoagulation for cataract surgery patients. Nurs
Forum 41:30, 2006; Hunter DG et al: Inferior oblique muscle injury from local anesthesia for cataract surgery.
Ophthalmology 102:501, 1995; Hwang JM et al: The Lancaster red-green test before and after occlusion in the
evaluation of incomitant strabismus. J AAPOS 3:151, 1999; Phillips PH et al: Superior oblique overaction from local
anesthesia for cataract surgery. J AAPOS 5:329, 2001; Rainin EA et al: Postoperative diplopia and ptosis. A
clinical hypothesis based on the myotoxicity of local anesthetics. Arch Ophthalmol 103:1337, 1985; Salama H et al:
Anesthetic myotoxicity as a cause of restrictive strabismus after scleral buckling surgery. Retina 20:478, 2000; Scott
AB et al: Bupivacaine injection of eye muscles to treat strabismus. Br J Ophthalmol 91:146, 2007; Wachtel RE et
al: A simple method for deciding when patients should be ready on the day of surgery without procedure-specific
data. Anesth Analg 105:127, 2007.
Educational Objectives
| The goal of this program is to improve cooperation between all members of the anesthesia care team during ophthalmic
surgery and to reduce strabismus complications from local anesthetics after cataract surgery. After hearing
and assimilating this program, the participant will be better able to:
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| 1. Identify members of the anesthesia care team and improve communication and patient care before, during, and
after ophthalmic surgery.
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| 2. Review the historical identification of anesthetic myotoxicity.
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| 3. Describe the typical signs, symptoms, and clinical course of anesthetic myotoxicity.
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| 4. Demonstrate the proper approach to surgical correction of anesthetic myotoxicity.
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| 5. Avoid anesthetic myotoxicity in anterior-segment and posterior-segment ophthalmic surgery.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and planning committee
members to disclose relevant financial relationships within the past 12 months that might create any personal conflicts
of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in
health care and not a proprietary business or commercial interest. For this program, the faculty and planning committee
reported nothing to disclose.
Acknowledgements
Mr. Hirschman and Dr. Guyton spoke in Chicago at the 21st Annual Scientific Meeting of the Ophthalmic Anesthesia Society
, held September 28-30, 2007, and jointly sponsored by the Cleveland Clinic Foundation Center for Continuing Education
and the Ophthalmic Anesthesia Society. The Audio-Digest Foundation thanks the speakers and the sponsors for
their cooperation in the production of this program.
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