*4.4.6.4. Cleaning and decontamination of specific equipment can be discussed as follows*

handled with care to prevent exposure to skin and mucous membranes, clothing and envi‐ ronment. All reusable equipments are to be cleaned and sterilized before using for another

*4.4.6.1 .High level disinfection (HLD), Intermediate level disinfection (ILD) and Low level disinfection*

High level disinfection (HLD) is a process that kills all microorganisms except large numbers of bacterial spores. The Food and Drug Administration definition of HLD is a sterilant used for a shorter contact time to achieve 106 log kill of an Mycobacterium sp. HLD chemicals can also be used for sterilization only with extended exposure time. The examples are glutaralde‐ hyde 2%, Hydrogen peroxide 7.5%, Hydrogen peroxide and peracetic acid 1% / 0.8%, Hypo‐ chlorite and hypochlorus acid i.e. 650-675 ppm and 400-450 ppm respectively etc. HLD can be used for heat – sensitive semi critical patient care equipments e.g. Gastrointestinal endoscopes,

Intermediate level disinfection (ILD) – ILD is defined as a disinfection procedure that is cidal for Mycobacteria, vegetative bacteria, most viruses and fungi but does not kill bacterial spores. Tuberculocide germicide does not prevent transmission of tuberculosis in health care set – ups. The term tuberculocide is used to denote germicidal potency of disinfectant. The examples of ILD are hypochlorite, alcohols, phenols etc. ILDs are mainly used for soiled noncritical patient care items or surfaces contaminated with visible blood/

Low level disinfection (LLD) is a process that kills most vegetative bacteria, some fungi and some viruses (lipophilic viruses) etc in ≤ 10 minutes. LLD includes some chlorine based products, phenolics and quaternary ammonium compounds or 70-90% alcohol. LLD is used

The definition of HLD, ILD and LLD correlates well with Spaulding's classification of devices [61]. The Equipment/device is defined as **Critical** if the medical device enter into a normally sterile tissue or vasculature and for reprocessing sterilization is required. The examples are

The medical devices are called **Semicritical** if the device can come in contact with mucous membrane or non intact skin. For reprocessing, sterilization is desirable but HLD is acceptable.

The **Noncritical** devices can be defined as devices that come in contact with intact skin, e.g.

In 1991, CDC has proposed an additional category as 'Environmental surfaces' to Spaulding's classification that do not come in contact with patients but serve as reservoir of resistant

Blood pressure cuff, Stethoscopes etc and for reprocessing ILD / LLD can be used.

patient.

16 Infection Control

*(LLD) [60].*

bronchoscopes etc.

body fluids/sputum/faeces/Mycobacteria.

*4.4.6.2. Critical, semicritical & non critical devices*

cardiac catheter, needle, surgical instruments, implants etc.

The examples are respiratory therapy equipment, some endoscopes etc.

for non critical patients care items.

*4.4.6.3. Environmental surfaces*

**Endoscopes :** Recently, in many operative and diagnostic procedures Endoscopes are used and hence, effective decontamination is essential for patient's safety [63]. Some endoscopes are available in both flexible and rigid construction. Modern flexible fibre optic scopes (bronchoscopes, cystoscpes, gastroscopes, sigmoidoscopes etc) cannot withstand high temperatures. These are very delicate, having multiple small channels and blind ends. Hence, they are very difficult to clean and decontaminate. Endoscopes and accessories which come in contact with sterile tissue are classified as critical items and sterilization or HLD should be done ideally. Endoscopes and accessories that come in contact with mucous membrane are put into semicritical items and should be treated with HLD after use. Endoscope sterilization or HLD involve the following steps i.e. disassembling the components, cleaning and disinfec‐ tion with HLD, rinsing the endoscope and its channels with sterile water to remove disinfec‐ tant, then flushing the channels with 70-90% ethyl or isopropyl alcohol and drying by forced air. Then the endoscopes are stored by hanging vertically with caps.

A logbook is to be maintained after each use and reprocessing by noting the patient's name, hospital registration number, the clinician who performed the endoscopy and HCW who did reprocessing and serial number of endoscopes etc. If any endoscope is used in a patient who has been subsequently diagnosed with CJD (Cruitzfeild Jacob disease), further follow up investigation must be done.

**Ventilators :** Mechanical ventilators are essentially used in Intensive Care Units (ICUs) and are common source of infection. Ventilator associated pneumonia is one of the commonest HAI after catheter associated UTI (CA-UTI). All HCWs must be trained to follow hand hygiene and use PPE while reprocessing ventilators or any other respiration devices. All disposable devices must be discarded. The ventilators should be cleaned to remove organic soil. The circuits and filters should be disposable so that it can be changed between patients.

**Suction equipment :** Preferably separate machine should be used for each patient. A fresh catheter must be used for every suction. After use the contents are discarded and bottle should be washed with detergent and water and then dried up. The tubing, lids, non return valve and bottles are autoclaved if required.

**Dental equipments :** Infection Control Practices regarding HBV and HCV are very important for dental equipments [64]. The instruments must be thoroughly cleaned before disinfection. High speed dental handpieces should be sterilized in between patients. Critical items like extraction forceps, scalpel blades, periodontal scalers etc. must be sterilised after each use. The semicritical items which come in contact with oral tissue i.e. bone amalgam condensers or syringes are sterilized and if cannot withstand heat, HLD may be done.

**Patient placement :** Adequate spacing is required to prevent transmission of HAI. Optimum spacing between beds is 1 – 2 meters. Single room with hand washing facilities with attached

Infection Control Practices in Health Care Set-Up

http://dx.doi.org/10.5772/55029

19

**Environmental Management Practices :** Safe drinking water supply, appropriate cleaning practices, housekeeping practices, laundry, pest control (mice, rodents etc) appropriate waste management facilities must be ensured to reduce HAIs. In isolation rooms, food should be

SARS is caused by a novel coronavirus – SARS Co – V [66] which could be found in sputum, tears, blood, urine and faeces. The virus is predominantly transmitted through droplets

Both Standard precautions and additional precautions are to be taken to prevent transmission. The patient must be placed in a single room and PPE must be used by all HCWs giving patient care, cleaning staffs, all laboratory staffs and sterilizing service workers. All waste from a SARS patient room should be treated as infectious waste. The specimens from a SARS patient should be transported in a leak proof bag (i.e. a plastic biohazard specimen bag). All infection control precautions must be followed while caring for SARS patient. A post mortem examination of SARS patient or probably having SARS is a very high risk procedure and should be avoided if possible. Staffs of the mortuary or funeral care home must be informed that the deceased had SARS. Embleming is not recommended. Even the preparation of the deceased should be

The risk of acquiring HIV infection after needle stick or sharps injury is less than 0.5% [67]. Standard precautions using PPE and proper disposal systems for needles and sharps should be followed. The HCWs should be trained in safe sharps practices. The serological testing of patients must be done as early as possible if there is needle prick or injury by sharps. Post

For HBV and HCV same precautions and infection control practices has to be followed as HIV. All HCWs at risk of exposure to HBV must be vaccinated. No post exposure therapy to HCV is available but seroconversion of HCWs must be documented. For occupational exposure to blood borne pathogens, counselling and clinical and serological follow up must be provided.

exposure prophylaxis should be started according to National guidelines.

toilet and bathroom is preferable to reduce transmission.

**6. Infection control precautions in special situation**

discharged during coughing, sneezing and talking by the patient.

served on disposable crockery and cutlery.

**6.1. Sever Acute Respiratory Syndrome (SARS)**

discouraged.

**6.3. HBV and HCV**

**6.2. HIV**

**Ophthalmic instruments :** Thorough cleaning of instruments followed by steam sterilization and if the instruments cannot withstand heat, low temperature sterilization with Ethylene oxide (EtO) can be done.

**Surgical instruments :** These may be cleaned manually or mechanically and sterilized [60]. Autoclaving is usually done but if the instrument is heat sensitive, low temperature steriliza‐ tion with EtO can be done [60].
