CORNEAL ABRASIONS WHEN DO I GET MY TAPE ON PowerPoint Presentation

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CORNEAL ABRASIONSWHEN DO I GET MY TAPE ON?! Laura Surike RN, BSN, SRNA Leah Abbott RN, BSN, SRNA

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OBJECTIVES AT THE END OF THIS PRESENTATION, THE LEARNER WILL BE ABLE TO: DEFINE WHAT IS A CORNEAL ABRASION LIST COMMON CAUSES OF CORNEAL ABRASIONS LIST TWO WAYS TO DECREASE THE CHANCE OF CORNEAL ABRASIONS STATE THREE WAYS TO TREAT A CORNEAL ABRASION

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“CORNEAL WHAT?.....I’M JUST TRYING TO GET MY INTUBATION AND ALL MY MONITORS ON BEFORE THE SURGEON YELLS AT ME FOR NOT HAVING THE DRAPES UP!” ---ANONYMOUS

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Why are We Talking About Corneal Abrasions? While rotating through various sites for clinical, every site taped the eyes differently Some taped the eyes before ventilating the patient, others after intubation, and some throughout the induction process Some sites used eye lubricant and others never used it Some sites used silk tape or opsite while others used commercial eye cut outs What we did find was there was NO consistency

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Currently there is no standard of care as to when to tape the eyes or how to tape the eyes What is known is that taping the eyes while undergoing GA helps to prevent corneal abrasions

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CORNEAL ABRASION THE MOST COMMON OCULAR COMPLICATION OF GENERAL ANESTHESIA

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Cornea The cornea is an avascular structure composed of 5 histologically distinct layers Protected by a precorneal tear film composed of 3 layers: lipid, aqueous, and mucin Lipid layer: Prevents evaporation of the aqueous layer and acts as a lubricant Aqueous layer: oxygenates the corneal epithelium Mucin layer: creates a hydrophilic surface on the corneal epithelium

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The precorneal tear film is regenerated by blinking Absence of blinking during general anesthesia renders the cornea vulnerable to injury

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How do Corneal Abrasions Occur? Cornea extremely sensitive to hypoxia Partial pressure of oxygen in cornea can decrease greatly in as little as 30 seconds of hypoxia Corneal hypoxia leads to edema →potential for loss of the epithelial layer →causing an abrasion Physiologic factors that alter corneal blood flow can predispose pts to corneal injury

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This includes conditions that ↓ arterial blood flow such as ↑ IOP, head malpositioning, or pressure from an incorrectly applied face mask ↓ venous return can also lead to corneal edema and subsequent abrasion 2 main mechanisms of perioperative corneal injury are mechanical abrasion or exposure-induced drying of the corneal surface

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CAUSES Damage from anesthesia mask, surgical drapes, and spillage of solution During Intubation: End of plastic watch bands, jewelry, hospital ID cards, stethoscopes, laryngoscope handles

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INTRAOP: GENERAL ANESTHESIA, LONGER CASE DURATION, POSITIONING, HEAD AND NECK PROCEDURES DURING EMERGENCE: PT RUBBING EYES (PULSE OX PROBE), MAKE-UP(MASCARA), RIGID O2 MASK THAT RIDES UP IN THE EYES

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OCULAR INJURY CAN OCCUR D/T: LOSS OF PAIN SENSATION OBTUNDATION OF PROTECTIVE CORNEAL REFLEXES ↓ TEAR PRODUCTION (BOTH BASAL AND REFLEX TEAR PRODUCTION) SWELLING OF DEPENDENT EYES WITH POSITIONING (PRONE, LATERAL) HIGHER INCIDENCE WITH PRONE AND LATERAL POSITIONS

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PATIENT VERBALIZES FOREIGN BODY SENSATION PAIN TEARING PHOTOPHOBIA ↓ VISUAL ACUITY PAIN EXACERBATED BY BLINKING AND OCULAR MOVEMENT

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ABRASIONS USUALLY HEAL SPONTANEOUSLY WIHTIN 72 HRS WITHOUT SCARRING BUT SEVERE EYE INJURY CAN CAUSE CATARACT FORMATION AND IMPAIR VISION

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CORNEAL INJURIES CORNEAL ABRASION Complete destruction of corneal epithelium caused by trauma. (Did I check that lash reflex too hard?)

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CORNEAL EXPOSURE Damage to corneal epithelium caused by prolonged exposure or open eye

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Corneal exposure can also occur in pts who have difficulty closing the eyes completely (lagophythalmos or exophthalmus)

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ACUTE ANGLE-CLOSURE GLAUCOMA Flow of aqueous humor (intra-ocular fluid) becomes blocked by an obstruction in the drainage system

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Diagnosis If a corneal abrasion is suspected, diagnosis is confirmed with a cobalt-blue filtered light and the application of fluorescein

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Indications for Specialist Referral: Hx of significant trauma Worsening of symptoms despite tx Erosion or infiltrate around the edges of the abrasion (possible infection) Rare instances of healed epithelium poorly adhered to underlying layers that leads to recurrent corneal erosions

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TREATMENT No standard tx Symptomatic tx can include artificial tears Prophylactic application of antibiotic ointment (controversial but may help decrease ulcer formation) Eye patching used in the past --- recently studies are showing that patching not helpful and may delay healing Small abrasions often need no tx  usually heal within 24-72 hrs

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Topical NSAIDS such as diclofenac or toradol can help reduce pain No topical anesthetics because they can hinder healing, mask worsening symptoms, and lead to keratitis and damage corneal epithelium Symptoms usually resolve in 2 months without complication No improvement in 24 hrs, consult ophthalmology

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Benchmark Study The Benchmark study that examined taping the eyes in relation to corneal abrasions was performed in 1977 by Batra & Bali Study 0f 200 patients divided into 2 groups Group 1 eyes were left uncovered Group 2 eyes were deliberately closed with tape or vaseline gauze

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Benchmark Study In group 1, 59/100 participants had eyes that remained partially open. The other 41 had natural approximation of the eyes Batra and Bali found that 26/59 (44%) whose eyes remained partially opened had corneal abrasions after fluorescein eye staining was performed postoperatively Those with natural approximation of the eyelids and all those in group 2 were not found to have a corneal abrasion

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Benchmark Study Eyes were checked for corneal abrasions via fluorescein eye stain testing Positive staining (which indicated a corneal abrasion) was present only in the inferior third of the cornea of those who developed corneal abrasions. This was the only area of the eye left exposed while under GA This was the 1st study examining corneal abrasions and proved without a doubt that eyes should be taped or closed when the patient is undergoing GA

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Ranked 6th in Importance to Avoid Corneal abrasions are the most common ocular complication while undergoing GA, however; corneal abrasions are not one of the most common complications of undergoing GA A study conducted by Macario, Weinger, Truong and Lee (1999) examined anesthesia outcomes that were common and important to avoid

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Based on the ranking of 56 anesthesiologists, corneal abrasions were ranked 29th out of 33 outcomes in frequency of occurrence while undergoing routine outpatient surgery However, when asked about what outcomes are important to avoid, corneal abrasions were ranked 6th out of 33 outcomes Although not frequently occurring, corneal abrasions are certainly important to avoid

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Costly Another reason that corneal abrasions and eye injuries are important to avoid are the costly monetary rewards that can be received after eye injuries are sustained In a closed claim analysis project performed by American Society of Anesthesiologists in 1992, 3% of all claims were related to eye injury (71/ 2,046) Of those eye injuries, 25/71 (35%) were due to corneal abrasions and 83% occurred while under GA (Gild, Posner, Caplan & Cheney)

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Costly Of the 71 patients that sustained eye injuries, the patient received compensation in the form of payment in 70% of the cases Patient rewards after sustaining eye injury from anesthesia ranged from $25.00- $1,000,000.000 (Gild, Posner, Caplan, Cheney, 1992) Average cost of treating a corneal abrasion was $3,000.00 and permanent injury persisted in 12% of the cases

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Costly Standard of care for eye protection was ONLY found in 41% of the cases! Reasons they found in their study for corneal abrasions were the following: Patient movement Spillage of chemicals or prep solution Direct trauma to the eye from OR padding, needle from retrobulbar block, face mask and laryngoscope falling into the eye

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Most Common Eye Injury in Multiple Studies In multiple studies examining eye injuries in non- ocular surgery, corneal abrasions were the number one eye complication A retrospective study by Roth et al. (1996) found that the most common eye injury was also corneal abrasions

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Most Common Eye Injury in Multiple Studies They found that 21 out of 34 (62%) patients who sustained eye injuries from a group of 60,965 patients had corneal abrasions In Roth et al. study they found a cause of corneal abrasions in only 21% of the cases. The causes they could determine were loosening of tape covering the eyes, iodine prep dripping into the eye and trauma from a intravenous pole falling into the eye

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Most Common Eye Injury in Multiple Studies In another retrospective study, Yu et al. (2010) found that 10 of 24 (42%) patients, who sustained eye injuries post- operatively from a study of 75,120 operative cases, had corneal abrasions Yu et al. in their study found corneal injury to be from incomplete closure of the eye lid, talcum powder falling in the patients’ eye from gloves and surgeons request that the eyes be left uncovered

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Multiple Factors Can Lead to Development of Corneal Abrasions Physiological changes Mechanical trauma Chemical trauma Positioning Duration of Surgery Location of surgery

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Some of these factors are preventable while other are out of our control. As CRNA’s and SRNA’s we have a responsibility to protecting the patient and on a daily basis we perform actions that help to prevent corneal abrasions

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Physiological Changes of the Eye Under General Anesthesia Abolishment of normal protective eyelid reflexes Failure of the eyelids to close (lagophthalmos) Abolishment of blink reflex Masking of normal perception of pain Decreased tear production Abolishment of the ability of the globe to turn upwards (Bells Phenomenon abolished)

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Physiological Changes Loss of eye lid reflex This reflex closes the eyelid and helps to protect the eye from injury When this is lost the eye is then at risk for incomplete closure of the eyelids (lagophthalmos) and exposure of the cornea to the dry operating room air

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Physiological Changes Failure of the eyelids to close is called lagophthalmos Due to loss of blink and eye lid reflex The study by Batra and Bali (1977) found that in their study, 59% of the patients had incomplete eyelid closure while under GA This exposes the eye to air and drying of the cornea

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Physiological Changes Loss of Blink Reflex Normally a pre-corneal tear film is present protecting the cornea. The blink reflex replenishes the pre-corneal tear film When this reflex is obtunded, the eye is predisposed to drying If the eye is left open, this can rupture the pre-corneal tear film and dry patches can form on the cornea

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Physiological Changes Pain perception is lost under GA A insult to the eye may occur but the patient may be unable to feel it and react while being under the effects of general anesthesia

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Physiological Changes Decreased basal tear production A study by Krupin, Cross & Becker (1977) found that tear production was greatly reduced by GA In their study they measured tear production at various time intervals in 20 patients undergoing GA. Ten minutes after GA was in progress, there was a significant change in tear production (P<.001). At the 30 minute interval, tear production was further reduced (P<.001) as well as at the 60 minute interval (P<.001)

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Physiological Changes Even when surgery is over, decreased basal tear production can persist found Grover, Kumar, Sharma, Sethi and Grewal (1998) in their study of 150 patients under GA They divided the patients into 3 groups all which had an overall reduction in basal tear production when preoperative and postoperative basal tear production values were compared With a reduction in basal tear production, the cornea is predisposed to drying perioperatively

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Physiological Changes Bells Phenomenon is abolished This is when the globe turns upwards placing the cornea under protection of the upper eyelid during sleep 42% of the population has this and when a patient undergoes GA this phenomenon is abolished Cornea is then left unprotected if the eye is left open

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Bells Phenomenon

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Risk Factors and Co-Morbidities that Increase Risk of Corneal Abrasion Age > 41 years old in women and post-menopausal Graves Disease Anemia

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Risk Factors Study by Craig and Tomlinson (1995) found that women >41 years old were at increased risk for corneal abrasions As women age there is a decrease in prolactin and estradiol In their study they found in women <41 years old, there was increased tear flow and lower tear osmolality compared to those > 41 years old

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Risk Factors Another study by Mathers, Stovall, Lane, Zimmerman and Johnson (1998) found that in women undergoing menopause, when prolactin and sex hormone levels are decreased, there is reduced tear production Those > 41 years of age and going through menopause or post-menopausal are at increased risk for corneal abrasions

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Risk Factors Graves Disease Patients with this disease can have exophthalmos which can result in difficulty closing the eye A study by Martin, Weingarten, Gunn, Lee, Mahr, Schroeder and Sprung (2009) found graves disease to be associated with corneal injury after univariate analysis

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Risk Factors Anemia Its mechanism related to corneal abrasions is currently not understood Also there is no method to treat preoperative anemia that is superior to another to reduce corneal abrasions Only one retrospective study by Yu et al. (2010) has identified anemia as a significant risk factor but worth mentioning

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Mechanical Trauma Pressure on the Eye Direct trauma due to various reasons

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Mechanical Trauma Pressure on the eye can be from many things but commonly from facemasks Pressure applied to the globe can reduce choroidal blood flow which decreases blood flow to the peripheral cornea This is can also be a mechanism that predisposes a patient to developing a corneal abrasion in the lateral and prone position Extremely important to check eyes frequently

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Mechanical Trauma

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Mechanical Trauma Watchbands, wrist jewelry Laryngoscope Dangling name badge, necklace or stethoscope Surgical drapes Checking the eyelid reflex Incomplete closure of the eye when mask ventilating Patient rubbing their eyes post-operatively

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Chemical Trauma Chemical solutions for various surgeries may be used to clean the face These solutions can drip into patients eyes if not properly protected/ covered/ closed In the study by Gild et al (1992), out of 71 patients with injuries, the mechanism of injury was spillage of preparation solution in 9 cases

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Duration of Surgery Longer duration of surgery was found to be a risk factor for developing a corneal abrasion Batra and Bali (1977) found that the maximal incidence of corneal abrasion was seen in patients undergoing GA between 90- 150 minutes No corneal abrasions were found in patients undergoing GA < 60 minutes in their study

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Duration of Surgery In a retrospective study by Roth et al. (1996) an independent risk factor for developing a corneal abrasion was length anesthesia time (>4 hours). They found that as the hours of anesthesia given increased, the risk for developing a corneal abrasion increased A more recent retrospective study by Martin et al. (2009) also found this to be true in their findings

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Positioning Prone and Lateral positions In these positions there is increased risk of pressure on the eye, mechanical trauma during positioning and increased ICP from decreased venous return Yu et al. (2010) in their retrospective study found the lateral and prone positions statistically significant Roth et al. (1996) also found this in their study

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Location of Surgery Head and Neck Surgery Procedures involving the head and neck increase the rick of developing a corneal abrasion since the surgical field is closer the eyes There may be direct trauma to the eye from the surgeon or instruments used These procedures may not allow the surgeon to tape the eyes because it could be in their surgical field

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Research There were 2 studies that retrospectively looked at the incidence and risk factors for corneal abrasions Some risk factors were the same while others were different

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Research Roth, Thisted, Erickson, Black and Schreider (1996) found the following as statistically significant risk factors: Duration of surgery Inpatients undergoing surgery Patients having surgery on a Monday Use of general anesthesia Head and neck surgery Lateral position

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Research Yu, Chou, Yang and Chang (2010) in their study found the following as statistically significant risk factors: Anemia Head and neck surgery Lateral and prone positioning Fiberoptic intubation Deliberate hypotension Duration of anesthesia

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Research Martin, Weingarten, Gunn, Lee and Schroeder (2009) performed a prospective study in which they initiated a performance improvement initiative and then a time period was examined looking at corneal abrasions. Risk factors they found statistically significant were the following: Duration of anesthesia Head and neck surgery Graves disease ASA status of I or II Anesthesia provider (SRNA’s!!!!!)

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Strategies for Eye Protection Now that we know different mechanisms and risk factors for corneal abrasions, how do we protect against them? Very limited research assessing different methods to protect the eyes during the course of general anesthesia

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PREVENTION According to Barash, “…tape the eyelids closed immediately after induction, and during mask ventilation and laryngoscopy.” Tape eyes after induction immediately after the loss of lid reflex (before mask ventilation or endotracheal intubation) Be very careful with checking eyelid reflex Take care when taping eyes to fully shut and closing eyelids Care regarding dangling objects when leaning over pts Close observation as pts awaken (pts often try to rub their eyes or nose as they recover from the effects of anesthesia)

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Various Prevention Methods Taping the eyes Lid taping only Eye drops Hydro- gel Ointments Lid taping plus ointment Goggles

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Prevention Taping/ Opsite/ Eye Cutouts Without a doubt taping the eye is necessary during GA and the best method to help protect the eye Ensure that the edges of the eyelid are approximated and the tape is secure Check eye tape periodically → esp. after repositioning Tape may lose adherence with exposure to tears or moisture → retape when indicated by visual inspection

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Prevention Lid taping only Good for cases less than 90 minutes Supine patient position No high risk surgery (head/neck) No exophthalmos or lagophthalmos Great if tape won’t come off and lids remain shut Avoids post-op blurring of vision that is associated with ointment

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Prevention Methylcellulose Eye Drops Good lubricant Easy to Instill and Cheap When compared to petroleum based ointment, methylcellulose eye drops offered better protection of the eye in a study by Boggild-Madson, Bundgarrd- Nielsen, Hammer and Jakobson (1981). They found lower rates of edema, pink eye and blurred vision in the methylcellulose group

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Prevention Hydro-gel Never seen it used before but an option A study conducted by Smolle, Keller, Pinggera, Deibl, Rieder and Lirk (2004) compared clear hydro- gel to eye ointment in providing eye comfort after surgery The use of hydro- gel when compared to eye ointment was found to have reduced eye inflammation, reduced eye itching upon emergence, better patient comfort, less blurred vision and less adherent eye lashes

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Prevention Ointments Mixed research results Advantages Good for longer case to help keep eye lubricated Disadvantages of ointments: Occasional allergic reaction Flammability → makes use undesirable during surgery around face and contraindicated during laser surgery Blurred vision in early post-op period The blurring and foreign body sensation associated with ointments may ↑ incidence of post-op corneal abrasions if it triggers excessive rubbing of the eyes

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Prevention Petroleum ointment was found to cause edema, pink eye, and blurred vision more than the use of methylcellulose solution in a study by Boggild-Madson, Bundgarrd- Nielsen, Hammer and Jakobson (1981)

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Prevention Another study conducted by Siffring and Poulton (1987) assessed the prevention of ocular complications during general anesthesia This study use 4 groups to evaluate different methods of eye protection: Group A used Lacri- lube petroleum ointment and tape Group B used Duratears ointment and tape Group C used methylcellulose drops and tape Group D used only hypoallergenic tape

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Prevention Both groups A and B found blurred vision present post operatively Both Group C and D did not use petroleum based ointments to protect the eyes and only one or less subjects complained of blurred vision

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Prevention Lid taping plus ointment: Good for cases lasting >90 min Good for high risk procedures and position Gives additional protection if there is concern about tape coming off Check proper eye closure and reapply ointment every 60-90 minutes in high-risk patients

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Prevention Goggles May help with prone cases but offer little advantage to reduced eye dryness

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Prevention Apply pulse oximeter to non-dominant hand Do not place pulse oximeter on index or middle finger

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Prevention

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Prevention

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Recent Study Recent prospective study by Martin, Weingarten, Gunn, Lee and Schroeder (2009) in which they initiated a performance improvement initiative within their anesthesia department whose aim was to reduce perioperative corneal abrasions Initiative consisted of 2 parts: 1st phase increased awareness of the provider by sending an email when a patient of theirs experienced a corneal abrasion 2nd phase consisted of formal teaching of personnel regarding factors that lead to corneal injury

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Recent Study Researchers evaluated the rate of corneal injuries during the 1st initiative period in which there was a decrease in corneal abrasions (1.51 corneal abrasions per 1,000 surgeries at the start of the study vs. 1.37 corneal abrasions per 1,000 at the end of 1st initiative period ) During the 2nd initiative period, the rate of corneal injury decreased even further (0.79 corneal abrasions per 1,000 surgeries)

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Recent Study In this study procedure they instructed the anesthesia provider to tape the eyes shut during induction as soon as the eyelid reflex disappeared and before any airway management. Emphasis was made to assure the eyelid was fully closed This is the ONLY study that has mentioned when to tape the eyes! Huge gap in knowledge exists still!

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Gaps in Literature When to get your tape on!!! Ultimately, it is up to the anesthesia provider to decide when to tape the eyes We challenge you to try and tape the eyes during induction, after the lid reflex is lost and prior to mask ventilating the patient

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Conclusion Corneal Abrasions should be try to be prevented with every anesthetic given Many methods of eye protection exist but limited research as to which one is superior Literature suggests to tape eyes after the lash reflex is gone and prior to intubation Continue to strive to give the best care to patients with every anesthetic given

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References Barash, P., Cullen, B., Stoelting, M., Cahalan, M., Stock, M. (2009). Clinical Anesthesia, 6th Ed. 2009. Lippincott: Philadelphia, PA. Batra, Y.K., & Bali, I.M. (1977). Corneal abrasions during general anesthesia. Anesthesia and Analgesia…Current Researches, 56(3), 363-365. Cross, D.A., & Becker, B. (1977). Decreased basal tear production associated with general anesthesia. Archives of Ophthalmology, 9, 107-108. Gild, W.M., Posner, K.L., Caplan, R.A., & Cheney, F.W. (1992). Eye injuries associated with anesthesia. Anesthesiology, 76, 204- 208. Macario, A., Weinger, M., Truong, P., & Lee, M. (1999). Which clinical anesthesia outcomes are both common and important to avoid? The perspective of a panal of expert anesthesiologists. Anesthesia and Analgesia, 88, 1085- 1091.

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References Martin, D.P., Weingarten, T.N., Gunn, P.W., Lee, K., Mahr, M.A., Schroeder, D.R., & Sprung, J. (2009). Performance improvement system and postoperative corneal injuries: incidence and risk factors. Anesthesiology, 111(2), 320-326. Mathers, W.D., Stovall, D., Lane, J.A., Zimmerman, M.B., & Johnson, S. (1998). Menopause and tear function: the influence of prolactin and sex hormones on human tear production. Cornea, 17(4), 353-358. Roth, S., Thisted, R.A., Erickson, J.P., Black, S., & Schreider, B.D. (1996). Eye injuries after nonocular surgery: a study of 60,965 anesthetics from 1988 to 1992. Anesthesiology,85(5), 1020-1027. Smolle, M., Keller, C., Pinggera, G., Deibl, M., Rieder, J., & Lirk, P. (2004). Clear hydro-gel, compared to ointment, provides improved eye comfort after brief surgery. Canadian Journal of Anesthesia, 51(2), 126-129. Yu, H.D., Chou, A.H., Yang, M.W., & Chang, C.J. (2010). An analysis of perioperative eye injuries after noncoular surgery. Acta Anaesthesiology of Taiwan, 48(3). 122-129.