FDDC in an operating theater in Dr. Roberto Gilbert Hospital, Wednesday 5th of September 2018

Abstract

А STERISAFE® employee supervised the Full-Depth Disinfection Cycle in the children’s hospital Dr. Roberto Gilbert Elizalde, Guayaquil, Ecuador.

The disinfection cycle took place in one of the hopitals operating theaters. The operating theater had a volume of 115 m3.

Samples were taken after manual cleaning, before FDDC and after the FDDC cycle. Please read the full report below, which will be visuality illustrating the approach and results with the aid of Hygicult® Total Plate Count (TPC).

Introduction

The Full-Depth Disinfection Cycle by STERISAFE uses ozone to decontaminate the air and surfaces for bacteria, vira and fungi. After the disinfection is completed the STERISAFE reverses the ozone gas into breathable oxygen, removes remaining particles and the room is disinfected and safe to use.

Methodology

This field test used Hygicult® TPC (Total Plate Counts) to illustrate visually the disinfection efficacy. The TPC plates show the reduction of the colony forming units (CFUs) by comparing before and after disinfection with FDDC results.

Samples were taken after manual cleaning before Full-Depth Disinfection Cycle. Next, a sample after the (60minutes disinfection time) FDDC at the very same location.

The pictures show the exact locations where samples were taken and the Hygicult® TPC results.

Each Hygicult® TPC plate has two sides, market in this resport as Side A and Side B.

Hygiene mapping

STERISAFE is using Hygicult TPC from Orion Diagnostica (Finland) for its hygiene mapping. It is a reliable, economic, and easy-to-use on-site surface hygiene monitoring tests.

It is intended for general hygiene monitoring as most common bacteria, yeasts, and moulds can grow on it. The slide is covered on both sides with Total Plate Count (TPC) medium that supports the growth of the most common bacteria and fungi. The medium contains neutralising agents making the product suitable to be used in environments where disinfectant chemicals have been used. Each plates has two side of 9.8cm2 area each.

Hygicult is certified to be equivalent to the reference methods Trypticase soy agar (TSA) culture plates and contact plates. The certification has been made by NordVal Protocol 1, which complies with ISO 16140-2 1.

Each location is sampled twice. Results come after 4 to 5 days and are counted manually.

The Hygiene Mapping gives a general surface hygiene level of the room with a four colors code system. To determine the level, two factors are considered:

The level of contamination in CFU/sample. Above 5 CFU, the surface is considered contaminated
The type of surface with a level of criticality. The higher the risk of cross-infection via the given surface, the higher the criticality.

Type of surface
Criticality	Interpretation
	Very high risk of infection transfer if contaminated
	High risk of infection transfer if contaminated
	Moderate risk of infection transfer if contaminated
	Low risk of infection transfer if contaminated

Level of contamination
Hygiene Level	Interpretation
	>50% of surfaces contaminated or average contamination of >50 CFU/plates
	Between 20 and 50% of surfaces contaminated
	Between 0 and 20% of surfaces contaminated
	0% of surface contaminated

Total surface hygiene

Poor Hygiene	Moderate Hygiene	Acceptable Hygiene	Excellent Hygiene

General surface hygiene

Results from microbiological sampling on 5 locations in the operating theatre before cleaning:

Areas	Criticality	Results	Contamination level
High touch		4 out of 5 samples were taken on high touch areas. 2 of 4 of these areas where considered contaminated, with an average contamination of 9 CFU/plate, leaving the contamination level moderate to acceptable.
Under operating table		1 out of 5 samples were taken under the operating table. With 4 CFU/plate this leaves the contamination level acceptable.

Sample results

The results from the Avance CS2 Pro display is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.