Desinfection and Sterilisation MUDr. Lenka Černohorská, Ph.D Asepsis and antisepsis Asepsis: prevention against infection Antisepsis: process of removing infection

Decontamination methods SterilisationDestroy all microbes High degree desinfection Destroy almost all microbes, some alive DesinfectionDestroy pathogennous microbes DesinsectionDestroy harmful insects DeratisationDestroy harmful rodents

Rules of right decontamination Right method or preparate: Must kill microrganisms Can not destroy desinfected or sterilizated material Should have: enough intensity of various factors (temperature, concentration…), enough time lenght

DESINFECTION PREPARATES Peracetate acid (Persteril). For spores, funges and tuberculosis; 0,5% solution = high degree desinfection! It’s agresive, unstabile, decolourize textilie Peroxid hydrogen (H 2 O 2 ) - similar, less agresive, less effective – wounds washing. Halogen preparates: chlornans: NaOCl - known as Savo, limy chlor – for cesspools Chloramin B – for hands, surfaces Iod tincture (Jodonal B, Jodisol, Betadine), for wound desinfection.

Desinfection 2 KMnO 4 – wound washing Formaldehyd – for textil Kresol (lysol) effective, but smell, agresive, not often used Ethylalkohol – in mixture, not very effective; Highest effectivity has 70 % solution Surface active preparates - Ajatin - for skin desinfection, Septonex Anorganic acids and alkaline Hard metals – for water reservoires etc. Combinated preparates, for ex. Incidur

Sterilisation I Hot vapour under pressure (autoclaves). Vapour must be right saturated. Used for glass materials, metal, ceramic, pottery, porcelain, textil, rubber and some plastic materials. Temperature 121 – 134 °C. Hot air sterilisation (apparates with air circulation 180 °C 20 minutes or 170 °C 30 minutes or 160 °C hour). Used for metals, glass, porcelain and pottery. Flowing steam (Arnold apparatus) – sterilisation cultivation soils

Sterilisation II Gama rays: used for gloves for one use. Plasmatic sterilisation in highfrequency electromagnetic field (modern method) Chemical sterilisation via formaldehyd steam or ethylenoxid. Used in case, where physical methods can’t be used. Fire is used only for microbiological loops, damage other materials. Burn of rubbish. Other methods: fractionate sterilisation, filtration of solution etc. - special methods, rare used

Before decontamination is often needed mechanical washing. After decontamination: for ex. ventilate rest of chemical solution. Don’t let instruments stay on table whole year etc.

Control of desinfection effectivity and sterilisation Control of sterilisation: chemical - indicators change their colour in specific temperature, biological - strains of Bacillus genus absolve all cycle and after that we discover if they alive. After desinfection we do swabs from desinfected surface or let the preparate influence to control strains.