Preoperative Care for Cataract Surgery: The Society for Ambulatory Anesthesia Position Statement.

Cataract surgeries are among the most common procedures requiring anesthesia care. Cataracts are a common cause of blindness. Surgery remains the only effective treatment of cataracts. Patients are often elderly with comorbidities. Most cataracts can be treated using topical or regional anesthesia with minimum or no sedation. There is minimal risk of adverse outcomes. There is general consensus that cataract surgery is extremely low risk, and the benefits of sight restoration and preservation are enormous. We present the Society for Ambulatory Anesthesia (SAMBA) position statement for preoperative care for cataract surgery.

Regional Anesthesia for Pediatric Ophthalmic Surgery: A Review of the Literature.

Ophthalmic pediatric regional anesthesia has been widely described, but infrequently used. This review summarizes the available evidence supporting the use of conduction anesthesia in pediatric ophthalmic surgery. Key anatomic differences in axial length, intraocular pressure, and available orbital space between young children and adults impact conduct of ophthalmic regional anesthesia. The eye is near adult size at birth and completes its growth rapidly while the orbit does not. This results in significantly diminished extraocular orbital volumes for local anesthetic deposition. Needle-based blocks are categorized by relation of the needle to the extraocular muscle cone (ie, intraconal or extraconal) and in the cannula-based block, by description of the potential space deep to the Tenon capsule. In children, blocks are placed after induction of anesthesia by a pediatric anesthesiologist or ophthalmologist, via anatomic landmarks or under ultrasonography. Ocular conduction anesthesia confers several advantages for eye surgery including analgesia, akinesia, ablation of the oculocardiac reflex, and reduction of postoperative nausea and vomiting. Short (16 mm), blunt-tip needles are preferred because of altered globe-to-orbit ratios in children. Soft-tip cannulae of varying length have been demonstrated as safe in sub-Tenon blockade. Ultrasound technology facilitates direct, real-time visualization of needle position and local anesthetic spread and reduces inadvertent intraconal needle placement. The developing eye is vulnerable to thermal and mechanical insults, so ocular-rated transducers are mandated. The adjuvant hyaluronidase improves ocular akinesia, decreases local anesthetic dosage requirements, and improves initial block success; meanwhile, dexmedetomidine increases local anesthetic potency and prolongs duration of analgesia without an increase in adverse events. Intraconal blockade is a relative contraindication in neonates and infants, retinoblastoma surgery, and in the presence of posterior staphylomas and buphthalmos. Specific considerations include pertinent pediatric ophthalmologic topics, block placement in the syndromic child, and potential adverse effects associated with each technique. Recommendations based on our experience at a busy academic ophthalmologic tertiary referral center are provided.

Malignant Hyperthermia-Susceptible Adult Patient and Ambulatory Surgery Center: Society for Ambulatory Anesthesia and Ambulatory Surgical Care Committee of the American Society of Anesthesiologists Position Statement.

This document represents a joint effort of the Society for Ambulatory Anesthesia (SAMBA) and the Ambulatory Surgical Care Committee of the American Society of Anesthesiologists (ASA) concerning the safe anesthetic care of adult malignant hyperthermia (MH)-susceptible patients in a free-standing ambulatory surgery center (ASC). Adult MH-susceptible patients can safely undergo a procedure in a free-standing ASC assuming that proper precautions for preventing, identifying, and managing MH are taken. The administration of preoperative prophylaxis with dantrolene is not indicated in MH-susceptible patients scheduled for elective surgery. There is no evidence to recommend an extended stay in the ASC, and the patient may be discharged when the usual discharge criteria for outpatient surgery are met. Survival from an MH crisis in an ASC setting requires early recognition, prompt treatment, and timely transfer to a center with critical care capabilities.

Succinylcholine for Emergency Airway Rescue in Class B Ambulatory Facilities: The Society for Ambulatory Anesthesia Position Statement.

Procedures in class B ambulatory facilities are performed exclusively with oral or IV sedative-hypnotics and/or analgesics. These facilities typically do not stock dantrolene because no known triggers of malignant hyperthermia (ie, inhaled anesthetics and succinylcholine) are available. This article argues that, in the absence of succinylcholine, the morbidity and mortality from laryngospasm can be significant, indeed, higher than the unlikely scenario of succinylcholine-triggered malignant hyperthermia. The Society for Ambulatory Anesthesia (SAMBA) position statement for the use of succinylcholine for emergency airway management is presented.

Ultrasound-guided ophthalmic regional anesthesia.

PURPOSE OF REVIEW: Needle-based and cannula-based eye blocks are 'blind' techniques prone to rare but serious complications. Ultrasound, an established adjunct for peripheral nerve block, may be beneficial for ophthalmic anesthesia application. The present review details the evolution of ultrasound-guided eye blocks, outlines safety issues, and reviews recent studies and editorial opinions. RECENT FINDINGS: Ultrasound-assisted ophthalmic regional anesthesia allows imaging of key structures such as the globe, orbit, and optic nerve. Recent findings reveal that needle path is not reliably predictable by clinical evaluation. Needle tips are frequently found to be intraconal, extraconal, or transfixed in the muscle cone independent of the intended type of block. In addition, contemporary human and animal studies confirm that real-time observation of local anesthetic spread inside of the muscle cone correlates directly with block success. SUMMARY: Ultrasound-guided ophthalmic regional anesthesia is evolving beyond simple visualization of the anatomy. Recent research emphasizes the imprecision of needle tip location without ultrasound and the key role of imaging local anesthetic dispersion. There is ongoing debate in the literature regarding the utility of routine ultrasound for eye blocks.

Proliferative Sickle Cell Retinopathy: Outcomes of Vitreoretinal Surgery.

PURPOSE: To report the clinical presentation and outcomes in patients who underwent surgery for proliferative sickle cell retinopathy (PSCR). DESIGN: Retrospective, consecutive case series. SUBJECTS: All patients who underwent vitreoretinal surgery for complications secondary to PSCR between January 1, 2014, and December 31, 2021, at a university referral center. METHODS: Retrospective consecutive case series. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), single operation anatomic success rate. RESULTS: The study included 65 eyes of 61 patients. Disease distribution included 24 (44.4%) eyes with hemoglobin SC disease, 14 (25.9%) with hemoglobin SS disease, 13 (24.1%) with sickle cell trait, and 3 (5.6%) with sickle cell-ß thalassemia. Preoperative transfusion was not performed in any study patients. Regional anesthesia with monitored anesthesia care (RA-MAC) was utilized in 58 (89.2%) eyes and general anesthesia in 7 (10.8%). In eyes that underwent surgery for retinal detachment (RD; N = 52) the rate of single operation anatomic success was 72.4% with combined scleral buckling/pars plana vitrectomy (SB/PPV; N = 29) compared with 47.8% with PPV alone (N = 23; P = 0.07). Mean BCVA at the last follow-up examination was 1.27 (20/372) in the SB/PPV group and 1.05 (20/226) in the PPV group (P = 0.48). In all SB cases, an encircling band was utilized and there were no known cases of anterior segment ischemia. All eyes that had surgery for vitreous hemorrhage (N = 13) underwent PPV with endolaser and mean BCVA improved from 1.67 (20/944) preoperatively to 0.45 (20/56) at last follow-up examination (P < 0.001). Mean preoperative BCVA, indication for surgery, single operation success rate, and mean BCVA at last follow-up examination did not differ based on sickle cell disease type (P > 0.05). CONCLUSIONS: In patients with RD, SB/PPV achieved slightly higher rates of single operation anatomic success compared with PPV alone. Visual acuity outcomes were similar in the 2 groups. The majority of patients received RA-MAC anesthesia and preoperative transfusions were not performed. There were no cases of postoperative anterior segment ischemia. Hemoglobin SC disease was the most common disease type in the current study and surgical outcomes did not differ between sickle cell disease types. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Evaluation of distal radial artery cross-sectional internal diameter in pediatric patients using ultrasound.

In this study, we measure the radial artery internal diameter (RAID) in children up to 4 years of age before and after the induction of anesthesia. A B-mode portable color Doppler ultrasound was used to measure the RAID. Three sets of measurements were taken for each child before and after the induction of anesthesia and with the wrist in the neutral and dorsiflexed positions. The reliability of the mean value of the RAID in the three sets in 24 patients was established. There were discrepancies between the RAID and the proposed catheter size in some individuals, which may not only render placement difficult but also have potential for arterial injury. There are good reasons to measure the RAID in small children prior to insertion of an intra-arterial catheter.

Evolving Use of Regional versus General Anesthesia for the Surgical Repair of Open Globe Injuries.

PURPOSE: The purpose of the current study is to report outcomes with the evolving use of regional anesthesia with monitored anesthesia care (RA-MAC) vs general anesthesia (GA) in the repair of open globe injuries. DESIGN: Retrospective, consecutive, comparative, nonrandomized clinical study. METHODS: The study includes 507 eyes of 507 patients with open globe injuries treated with either RA-MAC or GA at a tertiary referral center between 2015 and 2020. There was no predetermined protocol for selection of anesthesia method. However, based on experience and findings of prior research by this group, regional anesthesia with monitored anesthesia care was typically selected initially and changed to general anesthesia if warranted after evaluation of the patient and discussion with the surgeon. The main outcome measure was visual acuity at last follow-up. Results were compared to previously published study groups between 1995 and 2014. RESULTS: Primary closure of open globe injury was performed under RA-MAC anesthesia in 462 patients (91%) and under GA in 45 patients (9%). Zone 1, 2, and 3 injuries were recorded in 251, 170, and 86 patients, respectively. Zone 1 (96%, 240 of 251 patients) or zone 2 (92%, 156 of 170 patients) (P < .001) were more likely to be repaired under RA-MAC vs zone 3 injuries (76%, 65 of 86 patients). The improvement from presenting visual acuity was similar for the 2 anesthesia groups, 0.52 logMAR and 0.46 logMAR for RA-MAC and GA, respectively (P = .68, CI -0.3 to 0.2). The use of RA-MAC anesthesia for open globe injuries has increased at our institution from 64% in 1995-1999 to 91% in the present study, 2015-2020 (P < .00001). CONCLUSION: The current study demonstrates that with anesthesiologists experienced in ophthalmic regional anesthesia techniques, and appropriate case selection, RA-MAC can be safely used as an alternative to general anesthesia for open globe repair. Considerations when employing RA-MAC include a patient's ability to cooperate, position, and communicate for the duration of the globe repair.

Should rocuronium and sugammadex replace succinylcholine for airway emergencies in class B ambulatory anesthesia settings?

INTRODUCTION: In class B surgical facilities, where only oral or intravenous (IV) sedation is employed without the administration of volatile anesthetics, laryngospasm is among the most common airway complications. However, these facilities generally do not stock succinylcholine to avoid the cost of storing dantrolene for the treatment of malignant hyperthermia (MH). High dose IV rocuronium with sugammadex reversal has been suggested as an alternative to succinylcholine for airway emergencies. The aim of this paper was to evaluate the clinical utility, patient safety, and financial implications of replacing succinylcholine with rocuronium and sugammadex in lieu of stocking dantrolene in class B facilities. EVIDENCE ACQUISITION: A systematic review of the literature concerning neuromuscular blockade for airway emergencies in class B settings in adult patients was conducted. The MEDLINE and EMBASE databases were searched for published studies from January 1, 1990, to October 1, 2021. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used to assess the certainty of evidence. EVIDENCE SYNTHESIS: The search strategy yielded 1124 articles. After review, 107 articles were included, with 49 graded as "strong" evidence to provide recommendations for the posed questions. CONCLUSIONS: The use of succinylcholine in isolation without volatile agents has a low incidence of triggering MH. Laryngospasm is a common airway emergency that requires immediate treatment to avoid morbidity and mortality. Both succinylcholine and rocuronium-sugammadex provide adequate treatment of airway emergencies and rapid return of spontaneous ventilation, but succinylcholine has a superior economic and clinical profile.

Are ultrasound-guided ophthalmic blocks injurious to the eye? A comparative rabbit model study of two ultrasound devices evaluating intraorbital thermal and structural changes.

BACKGROUND: Since Atkinson's original description of retrobulbar block in 1936, needle-based anesthetic techniques have become integral to ophthalmic anesthesia. These techniques are unfortunately associated with rare, grave complications such as globe perforation. Ultrasound has gained widespread acceptance for peripheral nerve blockade, but its translation to ocular anesthesia has been hampered because sonic energy, in the guise of thermal or biomechanical insult, is potentially injurious to vulnerable eye tissue. The US Food and Drug Administration (FDA) has defined guidelines for safe use of ultrasound for ophthalmic examination, but most ultrasound devices used by anesthesiologists are not FDA-approved for ocular application because they generate excessive energy. Regulating agencies state that ultrasound examinations can be safely undertaken as long as tissue temperatures do not increase >1.5°C above physiological levels. METHODS: Using a rabbit model, we investigated the thermal and mechanical ocular effects after prolonged ultrasonic exposure to single orbital- and nonorbital-rated devices. In a dual-phase study, aimed at detecting ocular injury, the eyes of 8 rabbits were exposed to continuous 10-minute ultrasound examinations from 2 devices: (1) the Sonosite Micromaxx (nonorbital rated) and (2) the Sonomed VuMax (orbital rated) machines. In phase I, temperatures were continuously monitored via thermocouples implanted within specific eye structures (n = 4). In phase II the eyes were subjected to ultrasonic exposure without surgical intervention (n = 4). All eyes underwent light microscopy examinations, followed at different intervals by histology evaluations conducted by an ophthalmic pathologist. RESULTS: Temperature changes were monitored in the eyes of 4 rabbits. The nonorbital-rated transducer produced increases in ocular tissue temperature that surpassed the safe limit (increases >1.5°C) in the lens of 3 rabbits (at 5.0, 5.5, and 1.5 minutes) and cornea of 2 rabbits (both at 1.5 minutes). A secondary analysis of temporal temperature differences between the orbital-rated and nonorbital transducers revealed statistically significant differences (Bonferroni-adjusted P < 0.05) in the cornea at 3.5 minutes, the lens at 2.5 minutes, and the vitreous at 4.0 minutes. Light microscopy and histology failed to elicit ocular injury in either group. CONCLUSIONS: The nonorbital-rated ultrasound machine (Sonosite Micromaxx) increases the ocular tissue temperature. A larger study is needed to establish safety. Until then, ophthalmic ultrasound-guided blocks should only be performed with ocular-rated devices.

Considerations for Corneal Surgery With Patients in the 10th Decade of Life.

PURPOSE: The purpose of this study was to report the indications, ocular and systemic comorbidities, and surgical outcomes of corneal transplantation in patients older than 90 years. METHODS: A retrospective review was conducted to identify individuals 90 years and older who underwent corneal transplantation surgery at the Bascom Palmer Eye Institute between January 2013 and October 2020. Outcomes included best-corrected visual acuity and graft survival over time. Paired t tests were used to compare visual acuity preoperatively versus postoperatively. Graft survival was evaluated with Kaplan-Meier curves. RESULTS: Fifty-eight eyes of 52 consecutive individuals were included. The mean age of individuals was 92 ± 2 years; 26.9% were male; and 48.1% self-identified as non-Hispanic White and 38.5% as Hispanic. Postoperative follow-up was 14.7 ± 12.1 months. Of the 58 eyes, 44.8% (26/58) underwent penetrating keratoplasty, 46.6% (27/58) Descemet stripping automated endothelial keratoplasty, and 6.9% (4/58) keratoprosthesis. All surgeries were performed under monitored local anesthesia, without major complications. Surgical indications included pseudophakic bullous keratopathy (36.2%), glaucoma-associated corneal decompensation (27.6%), Fuchs endothelial dystrophy (25.9%), and perforated corneal ulceration (19.0%). The best-corrected visual acuity improved by 0.32 (95% confidence interval 0.14-0.50; P < 0.01) as early as 1 month postoperatively, and vision gains were sustained for at least 12 months. Graft survival probability at 12 months was 88%. CONCLUSIONS: Corneal transplantation is a safe and successful procedure in restoring the visual acuity for patients older than 90 years after careful preoperative evaluation. Further research is needed to evaluate the impact of corneal transplantation on quality of life in patients in the 10th decade of life.

Electroretinogram Recording for Infants and Children under Anesthesia to Achieve Optimal Dark Adaptation and International Standards.

Electroretinogram (ERG) is the only clinical objective test available to assess retinal function. Full-field ERG (ffERG) measures the panretinal rod and cone photoreceptor function as well as inner retinal function and is an important measure in the diagnosis and management of inherited retinal diseases as well as inflammatory, toxic, and nutritional retinopathies. Adhering to international standards and maintaining retinal dark adaptation are critical to acquire valid and reliable dark-adapted (scotopic) and light-adapted (photopic) ffERG responses. Performing ffERG in infants and children is challenging and often requires general anesthesia in the operating room. However, maintaining retinal dark adaptation in the operating room is becoming increasingly difficult given the numerous light sources from anesthesiology monitoring systems and other equipment. A practical and widely applicable method for ffERG testing is described in the operating room that optimizes retinal dark adaptation. The method reduces operating room time by dark-adapting the patient before general anesthesiology is instituted. The operating room is modified for dark adaptation and any remaining light source in the darkened operating room is minimized with the use of a modified portable foldable darkroom that encloses the patient's head and the ERG examiner during ffERG scotopic recordings. The simple method adheres to ffERG international standards and provides valid reliable scotopic and photopic ffERG recordings that are critical to assess objective retinal function in this young age group where subjective assessment of visual function such as visual acuity and visual fields are not possible. Furthermore, the ffERG is the gold standard clinical test in detecting early onset inherited retinal diseases including Leber congenital amaurosis where approved gene therapy has become available. In sedated conditions, very low amplitude ffERG signals can be detected due to minimal orbicularis muscle activity interference, which is particularly relevant in patients after gene therapy to detect improved amplitude responses.