›Do not instil pressure-lowering or dilating drops beyond what the retina service requests
›Positioning and activity
›Upright posture with the head elevated 30 to 45 degrees, including overnight, so blood settles inferiorly and clears the visual axis
›Avoid Valsalva, heavy lifting, and bending below the waist
›Emergency evaluation
›Urgent B-scan ultrasound and serial examination to detect an underlying tear or detachment
›Repeat B-scan over days if the haemorrhage does not clear enough for a fundus view
›Treat the cause
›Laser or intravitreal anti-VEGF for proliferative diabetic retinopathy
›Retinopexy for a tear, vitrectomy for non-clearing haemorrhage or an associated detachment
›Anti-VEGF dosing given by ophthalmology, not in the emergency department: bevacizumab 1.25 mg in 0.05 ml, ranibizumab 0.5 mg in 0.05 ml, or aflibercept 2 mg in 0.05 ml intravitreally
Anticoagulant and antiplatelet management
›Isolated posterior vitreous detachment
›Not a reason to stop, hold, or reverse any anticoagulant or antiplatelet agent
›Continue aspirin 75 to 100 mg orally daily; there is no evidence it worsens visual outcome in spontaneous vitreous haemorrhage
›Vitreous haemorrhage on an anticoagulant
›Do not reflexively reverse; weigh the thrombotic indication (mechanical valve, recent venous thromboembolism, recent stroke or transient ischemic attack) against an intraocular bleed that is usually self-limited
›Check INR and correct only a supratherapeutic value; aim for the therapeutic range, not full reversal, for an isolated intraocular bleed
›Any decision to hold is made jointly with ophthalmology and the team managing the anticoagulation indication
›Resumption
›Restart a held agent once the retina service confirms haemostasis and no imminent surgery requires it withheld
Analgesia, dilating, and pressure-lowering adjuncts
›Analgesia
›Uncomplicated posterior vitreous detachment is painless and needs no analgesia
›For incidental headache or ocular surface discomfort: paracetamol (acetaminophen) 1 g orally every 6 hours, maximum 4 g in 24 hours
›Maximum 3 g in 24 hours if over 65, low body weight, chronic alcohol use, or hepatic impairment
›Ibuprofen 400 mg orally every 6 to 8 hours with food, maximum 1200 mg in 24 hours, only if there is no active vitreous haemorrhage, no anticoagulant, and no renal or peptic contraindication
›Examination drops
›Tropicamide 1 percent one drop, repeated once after 5 to 15 minutes, for dilation
›Phenylephrine 2.5 percent one drop added for wider dilation; avoid the 10 percent concentration
›Proparacaine 0.5 percent one to two drops for examination only; never prescribe a topical anaesthetic for home use because of corneal melt and delayed epithelial healing
›Post-dilation intraocular pressure rise or acute angle closure
›Topical first line
›Apraclonidine 0.5 percent one drop, or timolol 0.5 percent one drop if there is no asthma, bradycardia, or decompensated heart failure
›Add a topical prostaglandin or pilocarpine only on ophthalmology advice
›Acetazolamide for a marked rise
›Acetazolamide 500 mg orally or intravenously once
›Then 250 mg every 6 hours only if pressure remains elevated and ophthalmology has not intervened
›Avoid in sickle cell disease or trait because systemic acidosis promotes sickling and raises intraocular pressure
›Avoid in sulfonamide allergy, significant renal impairment, and hypokalaemia
›Intraocular gas already in situ from prior surgery
›Nitrous oxide is contraindicated for any anaesthetic; it expands the bubble and can raise intraocular pressure to sight-threatening levels
›Avoid air travel, high-altitude travel, and hyperbaric oxygen until the retina service confirms the gas has resorbed
Routine emergency interventions that require caution or modification
›Systemic thrombolysis or full anticoagulation for a concurrent indication (acute ischemic stroke, pulmonary embolism, ST-elevation myocardial infarction)
›Can enlarge a vitreous or retinal haemorrhage and convert a small bleed into a vision-threatening one
›Not an absolute contraindication; document baseline visual acuity and ophthalmic findings, involve ophthalmology, and weigh against the systemic indication
›Therapeutic anticoagulation or antiplatelet therapy
›Continue for isolated posterior vitreous detachment; for vitreous haemorrhage correct only supratherapeutic levels rather than fully reversing
›Pharmacologic pupil dilation
›Can precipitate acute angle closure in a shallow anterior chamber; assess chamber depth first and recheck symptoms and intraocular pressure afterward
›Systemic anticholinergics, sympathomimetics, and nebulised ipratropium can do the same
›Topical anaesthetic
›For examination only; repeated or home use causes corneal epithelial toxicity and melt
›Intubation, procedural sedation, and general anaesthesia
›Avoid nitrous oxide if intraocular gas tamponade is present, because bubble expansion can cause an intraocular pressure spike and central retinal artery occlusion
›Minimise coughing, bucking, and Valsalva during airway management when a retinal tear or fresh haemorrhage is present
›Succinylcholine transiently raises intraocular pressure; this matters only with a coexisting open globe, not for a closed-eye posterior vitreous detachment
›Oxygen and hyperbaric therapy
›Routine supplemental oxygen is safe
›Hyperbaric oxygen is contraindicated with intraocular gas in situ
›Fluid loading, vasopressors, and mechanical circulatory support including intra-aortic balloon pump
›No direct effect on posterior vitreous detachment and none is contraindicated by it
›Manage the systemic condition normally; posterior vitreous detachment does not alter resuscitation
›Analgesia
›Avoid high-dose or prolonged NSAIDs and aspirin-containing compound analgesics when there is active vitreous haemorrhage; paracetamol is preferred