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The best treatment for eye irritation caused by CS spray

Three Part Question

In [patients with eye symptoms following contamination with CS spray] is [active blown air more effective than irrigation with water or normal saline] in [reducing the pain of corneal irritation and preventing corneal abrasions].

Clinical Scenario

A 28-year-old man is brought to the emergency department by ambulance. He was thrown out from a club following an argument with a bouncer. As he tried to escape from the bouncer he was sprayed in the eyes by another doorman. At the scene the paramedics tell you that the bouncer had a can of CS spray with him that had been confiscated by the police. He has watery and painful eyes with a foreign body sensation. You ask one of the senior nurses to perform an eye washout but she suggests that he would be better off standing in front of a fan and letting the air blow the CS particles off. You wonder how on earth they know this but remember that sister Milly Terry is a weekend warrior with the Territorial Army and that they use CS gas for Chemical, biological, radiological and nuclear (CBRN) training.

Search Strategy

Medline 1948 to 2011 week 28 using Ovid Interface.

EMBASE 1974 to 2011 week 28.

All EBM reviews—Cochrane DSR, ACP Journal Club, DARE, CCTR, CMR, HTA and NHSEED.
({exp o-Chlorobenzylidenemalonitrile or exp Tear Gases or cs tear or chlorobenzyl$.mp} AND {exp Eye or eye$.mp or}).

Search Outcome

34 papers were found of which none were relevant to our question


CS spray or o-chlorobenzylidene malonitrate is largely in use by police forces as a chemical incapacitant spray. In its aerosol form CS is dispersed as a fine dust and produces side effects that make its use as an incapacitant spray so useful. Severe local reactions occur within seconds to the mucous membranes and skin. Ocular symptoms such as lacrimation, blepharospasm, erythema of the conjunctiva and periorbital oedema occur, worse in contact lens wearers. Due to CS being highly soluble in water irrigation can increase the discomfort. Research is these circumstances will be challenging given patient symptoms.

Clinical Bottom Line

Wear Personal protective equipment (PPE), blow air directly into eyes using a fan if available ensuring no one is downwind. If irritation persists, copious irrigation with 2 l of cold water or normal saline but it must be cold as otherwise symptoms can worsen. If still persistent then a slit-lamp examination may be needed as there may be embedded particles that need removing.