Efficacy of dexmedetomidine as an adjuvant to local anesthetics in peribulbar block: a meta-analysis with trial-sequential analysis.

PURPOSE: To assess the role of dexmedetomidine as an adjuvant to local anesthetics (LA) in enhancing the duration and quality of peribulbar blocks for ophthalmic surgeries. DESIGN: Systematic review with meta-analysis and trial sequential analysis Methods: We systematically searched MEDLINE, Embase, and Cochrane for randomized controlled trials (RCTs) involving adult patients undergoing ophthalmic surgery under peribulbar block, comparing LA alone versus LA + dexmedetomidine. Risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI) were computed using a random effects model. Sensitivity and trial-sequential analyses (TSA) were performed to assess inconsistencies, weight type II and II errors, and estimate the required information size of the samples for all endpoints. RESULTS: Sixteen RCTs (1,220 patients) were included. Compared with LA alone, dexmedetomidine was associated with prolonged (1) motor block duration (MD 65.01 minutes, p<0.001) and (2) sensory block duration (MD 81.94 minutes, p<0.001); (3) reduced intraocular pressure (IOP) (MD -2.6 mmHg, p<0.001), and (4) decreased need for supplemental injections (RR 0.44, p=0.007). Additionally, dexmedetomidine showed (5) longer time to analgesic request (MD 97.15 minutes, p<0.001) and (6) increased surgeon satisfaction (RR 1.52, p=0.01). Sensitivity analyses and TSA were consistent across all endpoints, and the required information size was achieved for most endpoints, indicating that pooled analyses were reliable and sample sizes were sufficient. CONCLUSIONS: Compared with LA alone, dexmedetomidine significantly prolonged sensory and motor block duration and the time to the first analgesic request; decreased IOP and the need for supplemental injections, while increasing surgeon satisfaction.

Anestesia del tronco encefálico posterior a bloqueo retrobulbar en cirugía oftalmológica. Reporte de caso / Brainstem anesthesia after retrobulbar block in ophthalmic surgery. Case report

Resumen: La morbimortalidad perioperatoria en cirugía oftalmológica es baja, considerando que la mayor parte de la población que requiere estos procedimientos son pacientes de edad avanzada con múltiples comorbilidades. Embriológicamente el nervio óptico y las capas meníngeas que lo recubren se derivan del ectodermo y están estrechamente relacionadas con las capas meníngeas que recubren al sistema nervioso central, de esta forma la punción inadvertida de las mismas durante los bloqueos orbitarios provocan diseminación del fármaco por medio del líquido cefalorraquídeo a través del espacio subaracnoideo hasta el tronco encefálico. Se reporta el caso de paciente femenino de 61 años de edad, programada para lavado de cámara vítrea en ojo izquierdo. La técnica anestésica fue sedación más bloqueo retrobulbar; posterior a dicho procedimiento, se observa deterioro neurológico, alteraciones cardiovasculares, disminución de la saturación de oxígeno manteniendo ventilación espontánea, pero con obstrucción de la vía aérea; se da apoyo ventilatorio y se administra antihipertensivo, respondiendo favorablemente 40 minutos después del bloqueo retrobulbar. La relación entre un bloqueo orbitario y la aparición de sintomatología neurológica, cardiovascular y/o respiratoria debe suscitar sospechas de anestesia del tronco encefálico. Lo más importante es el reconocimiento y atención temprana de esta complicación para evitar secuelas neurológicas, cardiovasculares o incluso la muerte.

Abstract: Perioperative morbidity and mortality in ophthalmic surgery is low, considering that most of the population that requires these procedures are elderly patients with multiple comorbidities. Embryologically, the optic nerve and the meningeal sheaths that cover it originate from the ectoderm, are closely related to the meningeal layers that cover the central nervous system, whereby their inadvertent puncture during orbital blocks causes drug spread by the cerebrospinal fluid through the subarachnoid space to the brainstem. The case of a 61-year-old female patient is reported, programmed for lavage of the left eye vitreous chamber. The anesthetic technique was sedation and retrobulbar block; after this procedure, neurological impairment, cardiovascular alterations, decreased oxygen saturation were observed, maintaining spontaneous ventilation but with airway obstruction; ventilatory support is given and antihypertensive is administered, responding favorably 40 minutes after retrobulbar block. The relationship between an orbital block and the appearance of neurological, cardiovascular or respiratory symptoms should raise suspicion of brainstem anesthesia. The most important thing is early recognition and attention to this complication, to avoid neurological and cardiovascular sequelae or even death.

Efficacy of ropivacaine versus bupivacaine in preventing peribulbar block failure: A meta-analysis.

PURPOSE: Peribulbar block is considered a standard of care in ophthalmological practice due to its easy execution and minor complications. There is a paucity of studies confirming efficacy between ropivacaine and bupivacaine for this specific technique. We evaluated the efficacy of ropivacaine or bupivacaine in preventing total or partial peribulbar block failure in ophthalmic surgeries. METHODS: Meta-analysis of randomized clinical trials, comparing patients submitted to ophthalmic surgeries under peribulbar anesthesia with ropivacaine and bupivacaine. We searched in different databases for articles published until March, 2018. Data on patients, anesthesia, procedures and akinesia were tabulated. After calculating the chi-square of heterogeneity, we adopted a random-effects model with DerSimonian-Laird test, as well as an odds ratio and a 95% confidence interval. RESULTS: From the 310 articles identified, 21 studies were selected. The use of ropivacaine was considered a protective factor for ocular akinesia failure in peribulbar block when compared to bupivacaine (OR = 0.53, 95% CI = 0.35-0.81 and p value = 0.003). CONCLUSIONS: In ophthalmic surgeries, ropivacaine in peribulbar anesthesia is associated with lower rate of block failure when compared to bupivacaine.

A new surgical technique to treat corneal perforations using amniotic membrane and surgical adhesive / Nova técnica cirúrgica para tratamento de perfuração de córnea utilizando membrana amniótica e adesivo cirúrgico

The objectives of this study were to compare surgical techniques and the effects of using n-butyl 2-cyanoacrylate and bovine amniotic membrane to repair perforated lesions in corneas. Penetrating keratoplasty was performed in sixty New Zealand White rabbits under general anesthesia. Group 1 (G1) was treated with n-butyl 2-cyanoacrylate, group 2 (G2) received a fragment of amniotic membrane through the anterior chamber and application of n-butyl 2-cyanoacrylate over the lesion, group 3 (G3) was treated with the same technique as G2 with the addition of an amniotic membrane bandage covering the cornea and sutured in the limbus region, and group 4 (G4) was treated with an amniotic membrane sutured to the lesion and an amniotic membrane bandage sutured in the limbus region. Clinical, histological and histomorphometric examinations of the corneas were performed. The membrane acted as a barrier for aqueous humor in G2 and G3, thereby keeping the surface dry for adhesive application; it also prevented the adhesive from contacting intraocular structures. The groups treated with amniotic membrane and surgical adhesive showed better results than the groups treated with either material alone. Thus, the combination of the membrane with the adhesive is recommended for this type of lesion.(AU)

Os objetivos deste estudo foram comparar técnicas cirúrgicas e efeitos do n-butil 2-cianoacrilato e da membrana amniótica bovina na reparação de lesões perfuradas em córneas. Sessenta coelhos da raça Nova Zelândia Branca foram submetidos à ceratoplastia penetrante sob anestesia geral. O grupo 1 (G1) foi tratado com n-butil 2-cianoacrilato; o grupo 2 (G2) recebeu um fragmento de membrana amniótica pela câmara anterior e aplicação de n-butil 2-cianoacrilato sobre a lesão; o grupo 3 (G3) foi tratado com a mesma técnica aplicada ao G2, adicionando-se uma bandagem de membrana amniótica cobrindo a córnea e suturada à região do limbo; e o grupo 4 (G4) foi tratado com membrana amniótica suturada nas bordas da lesão e bandagem de membrana amniótica suturada na região do limbo. Foram realizados exames clínico, histológico e histomorfométrico. A membrana atuou como barreira contra o extravasamento do humor aquoso nos grupos 2 e 3, manteve a superfície seca para posterior aplicação do adesivo e impediu o contato do adesivo com as estruturas intraoculares. Os grupos tratados com o adesivo associado à membrana amniótica demonstraram melhores resultados do que aqueles tratados com cada material isoladamente. Assim, a combinação da membrana com o adesivo é indicada neste tipo de lesão.(AU)

A new surgical technique to treat corneal perforations using amniotic membrane and surgical adhesive / Nova técnica cirúrgica para tratamento de perfuração de córnea utilizando membrana amniótica e adesivo cirúrgico

The objectives of this study were to compare surgical techniques and the effects of using n-butyl 2-cyanoacrylate and bovine amniotic membrane to repair perforated lesions in corneas. Penetrating keratoplasty was performed in sixty New Zealand White rabbits under general anesthesia. Group 1 (G1) was treated with n-butyl 2-cyanoacrylate, group 2 (G2) received a fragment of amniotic membrane through the anterior chamber and application of n-butyl 2-cyanoacrylate over the lesion, group 3 (G3) was treated with the same technique as G2 with the addition of an amniotic membrane bandage covering the cornea and sutured in the limbus region, and group 4 (G4) was treated with an amniotic membrane sutured to the lesion and an amniotic membrane bandage sutured in the limbus region. Clinical, histological and histomorphometric examinations of the corneas were performed. The membrane acted as a barrier for aqueous humor in G2 and G3, thereby keeping the surface dry for adhesive application; it also prevented the adhesive from contacting intraocular structures. The groups treated with amniotic membrane and surgical adhesive showed better results than the groups treated with either material alone. Thus, the combination of the membrane with the adhesive is recommended for this type of lesion...

Os objetivos deste estudo foram comparar técnicas cirúrgicas e efeitos do n-butil 2-cianoacrilato e da membrana amniótica bovina na reparação de lesões perfuradas em córneas. Sessenta coelhos da raça Nova Zelândia Branca foram submetidos à ceratoplastia penetrante sob anestesia geral. O grupo 1 (G1) foi tratado com n-butil 2-cianoacrilato; o grupo 2 (G2) recebeu um fragmento de membrana amniótica pela câmara anterior e aplicação de n-butil 2-cianoacrilato sobre a lesão; o grupo 3 (G3) foi tratado com a mesma técnica aplicada ao G2, adicionando-se uma bandagem de membrana amniótica cobrindo a córnea e suturada à região do limbo; e o grupo 4 (G4) foi tratado com membrana amniótica suturada nas bordas da lesão e bandagem de membrana amniótica suturada na região do limbo. Foram realizados exames clínico, histológico e histomorfométrico. A membrana atuou como barreira contra o extravasamento do humor aquoso nos grupos 2 e 3, manteve a superfície seca para posterior aplicação do adesivo e impediu o contato do adesivo com as estruturas intraoculares. Os grupos tratados com o adesivo associado à membrana amniótica demonstraram melhores resultados do que aqueles tratados com cada material isoladamente. Assim, a combinação da membrana com o adesivo é indicada neste tipo de lesão...

Avaliação clínica preliminar do fechamento comparativo de incisões corneanas com sutura e biofill (película celulósica)

The cellulosis Biofill membrane, which has been utilized as a temporary substitute for skin in esthetic and repair surgery, has recently been tested in ophthalmology. With the objective to obtain an alternative for sutures that require the opening of the cornea through the anterior chamber, a comparative study was done to relate the closure of corneal incision by the use of suture and with the aid of Biofill. Five dogs, of unknow breed, and with varying weight and age, were used to perform these incisions. In one eye, the incision was closed with Biofill, while on the other a simple continuous suture was done. An analysis of the results was obtained by daily clinical examination and by use of ophthalmoscopy. The results obtained with the use of cellulosis Biofill pellicle (film) on the closure of corneal incisions, proved to be more efficient in comparison to' incisions closed by the usage of suture.

A membrana celulósica Biofill vem sendo utilizada como substituto temporário da pele em cirurgias estéticas e reparadoras, sendo recentemente testada em oftalmologia. Com a finalidade de obter-se uma alternativa para suturas em cirurgias que exijam a abertura da câmara anterior através da córnea, foi feito um estudo comparativo entre o fechamento de incisões corneanas com sutura e com Biofill. Foram utilizados 5 animais da espécie canina, sem raça definida, de peso e idade variáveis, nos quais foram realizadas incisões corneanas completas. Em um olho a incisão foi fechada com película celulósica, e no outro com sutura contínua simples. A avaliação dos resultados foi feita através de exames clínicos diários e da oftalmoscopia. Os resultados obtidos com a utilização do Biofill no fechamento de incisões corneanas, mostraram-se favoráveis quando comparados com a síntese por sutura.

AVALIAÇÃO CLÍNICA PRELIMINAR DO FECHAMENTO COMPARATIVO DE INCISÕES CORNEANAS COM SUTURA E BIOFILL (PELÍCULA CELULÓSICA)

The cellulosis Biofill membrane, which has been utilized as a temporary substitute for skin in esthetic and repair surgery, has recently been tested in ophthalmology. With the objective to obtain an alternative for sutures that require the opening of the cornea through the anterior chamber, a comparative study was done to relate the closure of corneal incision by the use of suture and with the aid of Biofill. Five dogs, of unknow breed, and with varying weight and age, were used to perform these incisions. In one eye, the incision was closed with Biofill, while on the other a simple continuous suture was done. An analysis of the results was obtained by daily clinical examination and by use of ophthalmoscopy. The results obtained with the use of cellulosis Biofill pellicle (film) on the closure of corneal incisions, proved to be more efficient in comparison to' incisions closed by the usage of suture.

A membrana celulósica Biofill vem sendo utilizada como substituto temporário da pele em cirurgias estéticas e reparadoras, sendo recentemente testada em oftalmologia. Com a finalidade de obter-se uma alternativa para suturas em cirurgias que exijam a abertura da câmara anterior através da córnea, foi feito um estudo comparativo entre o fechamento de incisões corneanas com sutura e com Biofill. Foram utilizados 5 animais da espécie canina, sem raça definida, de peso e idade variáveis, nos quais foram realizadas incisões corneanas completas. Em um olho a incisão foi fechada com película celulósica, e no outro com sutura contínua simples. A avaliação dos resultados foi feita através de exames clínicos diários e da oftalmoscopia. Os resultados obtidos com a utilização do Biofill no fechamento de incisões corneanas, mostraram-se favoráveis quando comparados com a síntese por sutura.