Cutting risk of viral aerosols in operating theatres
Viral infections present a critical health threat to medical professionals, especially when operations are being performed. During keyhole surgery for example, in which a small camera is inserted into the patient’s abdomen, it is necessary to inflate the patient with carbon dioxide, like a balloon. This enables both the camera to be able to see, and the surgeon to use other instruments. This is achieved via a valved device – the trocar – that penetrates the abdominal wall. “The challenge is that gas leaks out around the insertion point, and from the opening when the surgeon removes an instrument and inserts another,” says PORSAV project coordinator Ciaran Clissmann from Pintail in Ireland. “If the patient is infected with COVID-19 or some other infectious disease, there’s a risk that the gas inside the body will be contaminated with the virus.” Leaks can lead to a jet of possibly contaminated gas entering the operating room. The risk is significant enough that some professional surgical societies were advocating the cancellation of all keyhole surgery at the start of the COVID-19 pandemic.
Aerosol visualisation and leak capture
The EU-funded PORSAV project sought to make the operating environment safer by advancing a possible solution – aerosol visualisation and leak capture. “Aerosol leaks are made up of different gases in the air in the operating room,” explains Clissmann. “This makes it possible to ‘see’ them using a technology called Schlieren imaging, which visualises changes in gas density.” Prior to the PORSAV project, Schlieren image capturing technology was optimised by a team from University College Dublin. Medical equipment manufacturer Palliare had also developed a prototype aerosol-leak capture device, called the LeakTrap. This works by attaching rings around the trocar where it pierces the skin, and at the top, where instruments are inserted and removed.
Validation in clinical settings
The goal of the PORSAV project was to validate the LeakTrap device in clinical settings, and to then scale up production in order to make them available to hospitals across Europe and beyond. “We finalised the LeakTrap device design, and set up a mass manufacturing line in Poland,” adds Clissmann. “Clinical validation of the device was carried out in Dublin and Paris.” Over 100 patients were ultimately involved in trials – half with the devices in use, half without. Each operation was videoed using Schlieren imaging and analysed to demonstrate the extent of leaks with and without the devices. This work underlined the efficacy of the device in protecting surgeons.
Updated surgical practices
“The key success of this project has been taking a novel medical device from prototype to fully validated mass production in a very short time frame,” says Clissmann. “This project will benefit surgical staff, most notably nurses, who actually spend more time in the operating theatre than individual surgeons. Healthcare systems as a whole will benefit, by reducing risks to key personnel.” While COVID-19 is less of an issue than it was when the project began, surgical smoke and other contaminants are only just beginning to be understood. “There are many possible applications for being able to ‘see the invisible’, both in surgery and elsewhere,” notes Clissmann. The project team is currently working with the European Association for Endoscopic Surgery (EAES) to have the devices included in updated surgical guidelines. The LeakTrap is awaiting medical device approval in Europe, with FDA approval in the United States already in place.
Keywords
PORSAV, viral, health, infections, COVID-19, surgeon, surgical, trocar, keyhole surgery
