Clearing the air

Four Howorth Exflow UCVs, provided by Howorth Medical, are playing a major role in a new and innovative operating theatre at Broadgreen Hospital and Cardiothoracic Centre, Liverpool, UK.

Broadgreen Hospital wanted to go beyond the usual boundaries of operating theatre design and create a “barn theatre”, one large space in which a number of ultra-clean operating tables could function as efficiently next to each other as they would in four separate theatres.

A vital part of the design requirement was to ensure that if one of the four canopies or air conditioning systems failed, the other three tables could still be used safely. To achieve this, each canopy has its own air conditioning system, which automatically compensates for the changes if one goes down.

The open plan design clearly raises questions of cross contamination and patient privacy, which Howorth addressed in its design:

For multiple operations to take place in a single open space, it is essential that the ventilation system provides the protection against cross-contamination that would usually have been provided by the inter-vening theatre walls – the most effective method of achieving this is by the installation of UCVs. The Ex-flow 32 canopies used at Broadgreen, each provide a clean zone in excess of ten square metres

To create protection against potential bone and blood splatter and for patient privacy, the design allows for partially opaque screens, stopping 500mm from the floor, to be hung from the service beams around the canopies, if required

Howorth’s design is so innovative that no HTM standards currently exist for a theatre of this type, but the aim – for the theatre to reach the same UCV performance and requirements of HTM 2025 as a standard operating theatre, will set the benchmark by which future standards will be measured. Commissioning tests have recorded that the overall noise level within the open barn is only 52 dBA with all four UCVs operating at full speed, which exceeds the requirements of HTM for a single UCV.

Extensive smoke tests were undertaken by Howorth’s engineers and by Malcolm Thomas, the independent validations engineer appointed by the Royal Liverpool & Broadgreen University Hospital NHS Trust, to establish the effectiveness of the installed systems. In every case, the Exflow UCV systems fulfilled their required performance and the total installation was accepted for handover in August.

This design potentially offers many benefits, such as opportunities for enhanced team working and peer awareness of contemporary surgical practice and standards. In general, barn theatre design will allow more theatres to be put into smaller spaces and increase opportunities for the theatres to be used as a teaching facility. It is envisaged that the Broadgreen barn theatre, and others like it, will allow hospitals to progressively treat more people more quickly, safely and cost-effectively.

Howorth pioneered the development of an effective ultra clean air canopy which would protect the operating zone without the need for side walls. This culminated in the patented Exflow system, which utilises a concentrically graded airflow to optimise protection of the wound site, while minimising peripheral entrainment of external particulates.