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FOCUS POINTS
Ophthalmic procedures in children are mostly accomplished under general anesthesia with potent volatile anesthetics.
The airway is managed with a supraglottic device or endotracheal intubation with or without muscle relaxation dependent on duration and extent of the procedure.
Succinylcholine and post-administration fasciculations should be used with caution in these procedures; precurarization with a nondepolarizing muscle relaxant should be considered.
Releasing muscle tension and avoiding eye pressure can abolish the oculocardiac reflex (OCR) but anticholinergic medication administration may be required.
Serotonin 5-HT3 receptor antagonists (antagonists) and dexamethasone are effective in preventing postoperative nausea and vomiting (PONV).
Intravenous lidocaine and deep extubation are two useful modalities to avoid coughing during extubation in these procedures.
Retinopathy of prematurity is common in premature infants and treatment needs to be performed within 72 hours.
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The maximum growth of a child’s eyeball occurs during the first two years of life with an infant’s eyeball volume increasing by 40%.1 The outer transparent mucous membrane that covers the inner surface of the lids and the sclera is the conjunctiva (Figure 15-1). The conjunctiva is continuous with the skin at the margin of the lid. The sclera is a collagen containing outer fibrous layer of the eye. The cornea is an avascular, transparent layer that acts as the glass of a watch. The ophthalmic division of the trigeminal nerve supplies the sensory nerves to the cornea. The iris divides the anterior chamber from the posterior chamber and the round aperture in the center is the pupil. The iris, using a balance between parasympathetic mediated constriction and sympathetic mediated dilation, controls the amount of light entering the eye. The ciliary body contains the ciliary process that produces aqueous humor and the ciliary muscle, which allows a variable focus of the lens by altering the tension on the lens capsule. The lens is an avascular, transparent structure that separates the aqueous anteriorly from the vitreous posteriorly. It is suspended behind the iris by zonules that connect to the ciliary muscle. The retina is a thin multilayer neural membrane that lines the inner posterior two-thirds of the globe. Images are focused on the retina with signals sent to the brain. The optic nerve contains approximately 1 million axons that arise from the ganglion cells of the retina and exits the posterior portion of the globe. The blood supply for the optic nerve consists of branches of the central retinal artery, ophthalmic artery, and other internal carotid branches. The extraocular muscles consist of two oblique muscles which primarily control torsion movements and four rectus muscles that depress, elevate, adduct, and abduct the globe. Cranial nerve VI (abducens) innervates the lateral rectus muscle, cranial nerve IV (trochlear) innervates the superior oblique, and cranial nerve III (oculomotor) innervates the inferior oblique and superior, medial, and inferior rectus.2
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