Microdroplet and spatter contamination during phacoemulsification cataract surgery in the era of COVID‐19

Abstract

Importance Determine phacoemulsification cataract surgery risk in a Covid‐19 era. Background SARS‐CoV‐2 (Covid‐19) transmission via microdroplet and aerosol generating procedures present a risk to medical professionals. As the most common elective surgical procedure performed globally; determining contamination risk from phacoemulsification cataract surgery may guide personal protection equipment use. Design Pilot study involving phacoemulsification cataract surgery on enucleated porcine eyes by experienced ophthalmologists in an ophthalmic operating theatre. Participants Two ophthalmic surgical teams. Methods Standardised phacoemulsification of porcine eyes by two ophthalmologists accompanied by an assistant. Fluorescein incorporated into phacoemulsification irrigation fluid identifying microdroplets and spatter. Contamination documented using a single‐lens reflex camera with a 532 nm narrow bandpass (fluorescein) filter, in‐conjunction with a wide‐field blue light and flat horizontal laser beam (wavelength 532 nm). Quantitative image analysis using Image‐J software. Main Outcome Measures Microdroplet and spatter contamination from cataract phacoemulsification. Results With phacoemulsification instruments fully within the eye, spatter contamination was limited to <10 cm. Insertion and removal of the phacoemulsification needle and bimanual irrigation/aspiration, with irrigation active generated spatter on the surgeons' gloves and gown extending to >16 cm below the neckline in surgeon 1 and > 5.5 cm below the neckline of surgeon 2. A small tear in the phacoemulsification irrigation sleeve, presented a worse‐case scenario the greatest spatter. No contamination above the surgeons' neckline nor contamination of assistant occurred. Conclusions and Relevance Cataract phacoemulsification generates microdroplets and spatter. Until further studies on SARS‐CoV‐2 transmission via microdroplets or aerosolisation of ocular fluid are reported, this pilot study only supports standard personal protective equipment.

“COVID new normal” in ophthalmology: Implications for ophthalmologists, eye care, ophthalmic education and research

“…Although SARS‐CoV‐2 has been identified in tears, it is not clear whether these viral particles are infectious 8,9 . Phacoemulsification cataract surgery is a recognized cause of droplet generation, 14 but the evidence on aerosolization is mixed. McGhee et al 14 demonstrate that despite droplet formation, spread to the surgeon appears to be low and phacoemulsification surgery is probably safe using standard surgical precautions.…”

SARS‐CoV‐2 and COVID‐19 for the ophthalmologist

“…They are summarized briefly in Table 1. Simulations in the ophthalmic office and operating theatre have suggested that these measures significantly decrease the likelihood of SARS‐CoV‐2 infection in ophthalmology practice 125‐129 …”

Phacoemulsification and COVID‐19 risk

“…Absence of evidence does not mean evidence of absence, so studies such as that by McGhee et al 9 are needed to build our scientific evidence base and allow sensible conclusions regarding theoretical viral transmission from surgery. One extrapolation from the data presented by McGhee et al is that standard personal protection equipment (PPE)—surgical gown, gloves and mask—appear to provide adequate protection from droplets for those closest to the phacoemulsifier.…”

“…In terms of protecting surgeons and other operating theatre staff from exposure to possible infection from the patient for SARS‐CoV‐2, our focus should remain on our systems for mitigating the far more likely respiratory and droplet transmission, using the assumption that any patient may be a source of transmission 7,8 . However, evidence like that presented by McGhee et al 9 will help us learn to protect surgeons and others in the operating theatre from potential infective material produced by our most common surgical procedure.…”

“…While spread of the virus by aerosol has been proposed with some evidence, the predominant epidemiological evidence is that droplet transmission is the major vector. [6][7][8] In this issue of Clinical and Experimental Ophthalmology, McGhee et al 9 provide some practical evidence of droplet spread during routine phacoemulsification. While this does not address the actual infectivity of such droplet spatter, it is a timely and useful step on the way to an evidence base for the risk to cataract surgeons and other workers in the operating theatre.…”