Intracameral phenylephrine for surgical mydriasis and intraoperative floppy-iris syndrome: systemic adverse effects and optimal dose.

Phenylephrine, a potent sympathomimetic, induces mydriasis via iris dilator muscle contraction. Intracameral (IC) phenylephrine has been successfully used in cataract surgery for initial mydriasis, maintaining mydriasis, and management of intraoperative floppy-iris syndrome. Serious systemic adverse events (mainly cardiovascular) have been described with topical phenylephrine drops, but we found very little evidence of such adverse events associated with IC phenylephrine use. However, we suspect under-reporting of such adverse events, as they may instead be ascribed to anxiety, positioning, anesthesia, etc. Optimal dosage/concentrations for IC phenylephrine use in different purposes have not been fully studied. In the absence of robust evidence, we suggest that lower but effective IC phenylephrine concentrations are used: a lower concentration (0.31%), in conjunction with an anticholinergic and lidocaine, may be used for initial mydriasis. For management of intraoperative floppy-iris syndrome, 0.31% may be effective, though a higher concentration (1% to 1.25%) may be required.

Anaesthetic considerations for the surgical management of ocular hypotony in adults.

Ocular hypotony can occur from many causes, including eye trauma, ophthalmic surgery and ophthalmic regional anaesthesia-related complications. Some of these patients require surgical intervention(s) necessitating repeat anaesthesia. While surgical management of these patients is well described in the literature, the anaesthetic management is seldom discussed. The hypotonous eye may also have altered globe anatomy, meaning that the usual ocular proprioceptive feedbacks during regional ophthalmic block may be altered or lost, leading to higher risk of inadvertent globe injury. In an 'open globe' there is a risk of sight-threatening expulsive choroidal haemorrhage as a consequence of ophthalmic block or general anaesthesia. This narrative review describes the physiology of aqueous humour, the risk factors associated with ophthalmic regional anaesthesia-related ocular hypotony, the surgical management, and a special emphasis on anaesthetic management. Traumatic hypotony usually requires urgent surgical repair, whereas iatrogenic hypotony may be less urgent, with many cases scheduled as elective procedures. There is no universal best anaesthetic technique. Topical anaesthesia and regional ophthalmic block, with some technique modifications, are suitable in many mild-to-moderate cases, whilst general anaesthesia may be required for complex and longer procedures, and severely distorted globes.

Topical prostaglandin analogue use and cystoid macular oedema following uneventful cataract surgery: a randomised control trial.

BACKGROUND/AIMS: The association between the development of cystoid macular oedema (CMO) following uneventful cataract surgery and prostaglandin analogue (PGA) therapy has not been fully determined. The study aim was to investigate whether discontinuation of PGA therapy following uneventful cataract surgery affected the incidence of postoperative CMO. METHODS: A prospective randomised controlled trial of 62 eyes of 62 participants with ocular hypertension (OH) or primary open angle glaucoma (POAG) treated with PGAs prior to cataract surgery. Participants were randomised to continue with PGA therapy after cataract surgery (CPGA) (n=31) or to discontinue PGA therapy (n=31). The primary outcome measure was the development of CMO at 1-month postoperatively, determined by a masked observer assessment of optical coherence tomography scans. The secondary outcome measure was change from baseline intraocular pressure (IOP). RESULTS: The incidence of CMO was identical in both groups at 12.9% (4 of 31 eyes) at the 1-month postoperative visit (OR 1.000; 95% CI 0.227 to 4.415). At 1-month postoperatively, the IOP was significantly lower in the CPGA group compared with baseline IOP. CONCLUSION: Continuation of PGA therapy following uneventful cataract surgery in eyes with normal macular morphology did not increase the incidence of CMO. Continuation of PGA therapy significantly reduced IOP at 1-month postoperatively suggesting that, when indicated, it might be beneficial to continue PGA therapy in patients with POAG or OH after uneventful cataract surgery in the absence of other risk factors for developing CMO.

Sub-Tenon's anaesthesia for modern eye surgery-clinicians' perspective, 30 years after re-introduction.

Sub-Tenon's block (STB) is a good technique of local anaesthesia for many types of eye surgery. It has a relatively good risk profile, in that sight- and life-threatening complications appear to be extremely rare. STB has gained popularity in the last three decades, with refinements including different types of blunt metal cannula, plastic cannulae and 'incisionless' approaches. Usage of STB varies significantly across the globe. This narrative review documents the historical evolution of STB techniques, anatomical and physiological considerations, its utility and suitability, complications, explores the current practice and possible future applications.

Face-to-face upright seated positioning for cataract surgery in patients unable to lie flat: Case series of 240 consecutive phacoemulsifications.

PURPOSE: To present a case series of patients who were unable to lie flat for cataract surgery. SETTING: University teaching hospital, district hospital, and private practice, Norwich, United Kingdom. DESIGN: Prospective case series. METHODS: All patients had phacoemulsification using face-to-face upright seated positioning. The patient sits upright or semi-recumbent, and the surgeon sits or stands, facing the patient. The microscope is rotated forward, and surgery is done via an incision in the lower half of the cornea, using topical intracameral anesthesia. All 240 face-to-face cases, performed by the same surgeon, were prospectively recorded. The database included reasons for positioning difficulty, position adopted, and per-operative complications. Data on full systemic monitoring of 34 patients and satisfaction data on 90 patients were also recorded. RESULTS: In 13 years, 240 eyes (179 patients) had face-to-face surgery. Common diagnoses were severe kyphosis, orthopnea, or both. No patient was refused face-to-face surgery since the service was started. The rate of vitreous loss was 12 (5%) of 240 cases. However, all patients (100%) received a posterior chamber intraocular lens. No patient had any systemic adverse event, and vital signs remained stable during surgery. All respondents stated that they would be happy to have face-to-face positioning again. CONCLUSIONS: Face-to-face positioning, in the hands of an experienced surgeon, was an acceptably safe approach for patients unable to lie flat for cataract surgery. It might be the only option for some patients. However, all patients should be counseled regarding the increased risk for operative complications.

Preoperative Preparation and Anesthesia for Trabeculectomy.

Preoperative preparation should improve the likelihood of successful trabeculectomy surgery. The team can reconsider the appropriateness of the proposed surgery, and steps can be taken to maximize the chance of a good outcome. For example, adjustments to anti-hypertensive or anti-coagulant medications may be made, and topical ocular medications adjusted. Choice of anesthesia technique is of particular relevance to the trabeculectomy patient. Some anesthesia techniques are more likely to have serious complications, and glaucoma patients may be at higher risk of some sight-threatening complications, because the optic nerve is already damaged and vulnerable. Posterior placement of local anesthesia (retrobulbar, peribulbar, posterior sub-Tenon's techniques) could potentially damage the optic nerve, and thereby cause "wipe-out" of vision. Anesthesia technique may influence the likelihood of vitreous bulge and surgical difficulty. Regarding long-term control of intraocular pressure, there is no good evidence to indicate that any particular anesthesia technique is better than another. There is little high-quality evidence on this topic. The author's preferred technique for trabeculectomy is subconjunctival-intracameral anesthesia without sedation. How to cite this article: Eke T. Preoperative Preparation and Anesthesia for Trabeculectomy. J Curr Glaucoma Pract 2016; 10(1):21-35.

Severe adverse events associated with local anaesthesia in cataract surgery: 1†year national survey of practice and complications in the UK.

BACKGROUND: Recent years have seen a major change in practice of local anaesthesia (LA) for cataract surgery. AIMS: (1) To estimate current usage of LA techniques for cataract surgery, (2) to estimate the incidence of severe adverse events associated with each LA technique, (3) to compare with our previous 2003 study. METHODS: This was a prospective, observational study of routine practice. For 13 months in 2012-2013, the British Ophthalmological Surveillance Unit sent monthly mailings to all senior British ophthalmologists, asking for reports of 'potentially sight-threatening or life-threatening complications of LA for cataract surgery'. Current practice was assessed by questionnaire. RESULTS: Cataract surgery comprised 3.4% general anaesthesia, 92.5% LA alone and 4.1% LA with sedation. Techniques for the estimated 357 000 LA cataracts were: 8.8% peribulbar, 1.3% retrobulbar, 50.5% sub-Tenon's, 1.4% subconjunctival, 13.8% topical, 24.2% topical-intracameral LA. Severe sight-threatening complications included seven globe perforations, one cilioretinal artery occlusion and one severe corneal oedema. Severe life-threatening complications included one profound vasovagal episode, one silent myocardial infarction, one anaphylactic reaction and one supraventricular tachycardia. Under-reporting means that more complications probably occurred. CONCLUSIONS: There has been a large swing towards 'non-injection' LA in recent years. Serious adverse events were reported with all techniques except topical-intracameral and subconjunctival LA, though the incidence appears lower for 'non-injection' LA.

Extreme face-to-face positioning for cataract surgery with patient seated upright in motorized wheelchair.

We present a case of extreme positioning for cataract surgery. The 68-year-old man was unable to lie flat and found it difficult to transfer from his motorized wheelchair. He had poor mobility due to a stroke, slept upright because of orthopnea, and his neck extension was poor. After the options and risks were discussed, surgery was performed under topical intracameral anesthesia using face-to-face positioning with the patient seated upright in his wheelchair. The operating microscope was rotated toward the horizontal, and the surgeon stood at the patient's side with the patient's face almost upright. The right-handed surgeon used a temporal corneal incision (0 degree) in the left eye and an inferior incision (270 degrees) in the right eye. Surgery and recovery were uneventful. Given a preexisting epiretinal membrane in the left eye, the patient was very happy with the uncorrected distance visual acuity outcome of 6/9 in the right eye and 6/18 in the left eye.

Posterior capsule rupture rate with akinetic and kinetic block anesthetic techniques.

A systematic literature search was performed to identify prospective randomized studies comparing akinetic (sub-Tenon, peribulbar, or retrobulbar) and kinetic (topical or topical and intracameral) local anesthesia for phacoemulsification surgery. Only studies that stated the rate of posterior capsule rupture or that stated without qualification that there were no intraoperative complications were included. Of the initial 3182 articles, 15 papers met the inclusion criteria. The number of eyes ranged between 26 and 282 per group (mean 95.4 eyes per group), with a total of 2862 eyes. Eleven articles mentioned posterior capsule rupture specifically; 4 stated that no intraoperative complications occurred. Eleven (0.74%) of 1494 eyes in the akinetic group and 11 (0.80%) of 1368 eyes in the kinetic group experienced posterior capsule rupture. The chi-square test confirmed the difference was not statistically significant (P = .84). This analysis indicates that there appears to be no clinically or statistically significant difference in the risk for posterior capsule rupture between akinetic and kinetic local anesthesia techniques.

Face-to-face upright seated positioning for cataract surgery in patients who cannot lie flat.

We describe a technique for cataract surgery in patients unable to adopt the conventional face-to-ceiling position. A standard reclining operating chair and operating microscope are used. Patients are seated instead of lying down, with the chair back elevated 30 to 80 degrees above the horizontal and the operating microscope rotated 45 to 60 degrees to vertical. The surgeon is seated or standing, facing the patient. A clear corneal incision is used via an inferior, temporal, or inferotemporal approach under topical intracameral anesthesia without sedation. Results of this technique in a case series comprising 32 eyes are reported. The technique is useful for patients unable to adopt the traditional approach for cataract surgery and at high risk for complications from general anesthesia. It is technically challenging so should be attempted by experienced surgeons only.

Patients' preferences for positioning during phaco-emulsification under topical-intracameral anaesthesia.

In many eye departments it is routine to ask patients to lie completely flat for cataract surgery. However, many patients prefer not to lie completely flat, if given the choice. It is our practice to ensure patients are in a comfortable position before commencing surgery. We conducted a prospective observational study of our routine practice comprising 125 consecutive cataract operations conducted by a single surgeon with local anaesthesia (occasional phaco under general anaesthetic was not included). All patients were initially positioned lying flat on the reclining chair and were given the option of staying in that position throughout the operation or having the chair-back raised until they were comfortable. Only 27% (34 patients of 125 total) were happy to lie flat (angle between 0 degrees and 5 degrees ). The majority of our patients (62%--78 patients) preferred to sit up slightly, with the chair-back 10 degrees to 25 degrees above the horizontal; 8% (10 patients) of the patients were sited at an angle of 30 degrees to 35 degrees and 2% (three patients) needed to be sited at 35 degrees or more. Patients who sat up above 30 degrees generally had a medical reason such as orthopnoea (3%--four patients), back pain (5%--six patients), anxiety (2%--two patients), Meniere's disease (1%--one patient). Patients who sat up below 25 degrees chose this position for comfort or preference. Our results show that patient preferences for positioning during cataract phaco-emulsification under topical-intracameral anaesthesia should increase overall patient satisfaction without the need to compromise safety.

Serious complications of local anaesthesia for cataract surgery: a 1 year national survey in the United Kingdom.

BACKGROUND: The techniques of sub-Tenon's, topical and topical-intracameral local anaesthesia (LA) have become common in routine practice. AIMS: This study aimed (i) to estimate the frequency of various LA techniques used in cataract surgery, (ii) to estimate the incidence of severe adverse events associated with each LA technique, and (iii) to document these adverse events. METHODS: This was a prospective, 13 month observational study of routine practice in the UK in 2002-2003. The British Ophthalmological Surveillance Unit sent a monthly mailing to UK ophthalmologists, asking for reports of "potentially sight-threatening or life-threatening complications of LA for cataract surgery". Current LA practice was assessed by questionnaire. RESULTS: Cataract surgery comprised 4.1% general anaesthesia, 92.1% LA without sedation and 3.9% LA with sedation. Of the estimated 375 000 LAs 30.6% were peribulbar, 3.5% retrobulbar, 42.6% sub-Tenon's, 1.7% sub-conjunctival, 9.9% topical and 11.0% topical-intracameral LA. "Potentially sight-threatening complications" were mostly associated with retrobulbar and peribulbar techniques and "potentially life-threatening" complications with all techniques except topical/intracameral LA. Eight neurological complications consistent with brainstem anaesthesia were reported: 7 with peribulbar or retrobulbar LA. Poisson regression analysis strongly indicated that rates vary with technique (p<0.001 for "potentially sight-threatening" complications, p = 0.03 for "neurological" complications). Because of likely under-reporting, further complications probably occurred during the survey period. CONCLUSIONS: This large survey found a lower rate of reported serious complications with sub-Tenon's, topical and topical-intracameral LA compared with retrobulbar and peribulbar techniques. These "newer" methods may be preferable for routine cataract surgery.