Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Medical Gases Study guide Medical gas and suction safety CQC Regulation 12, 15 and 18 • HTMO2-O1B (Department of Health) Introduction to medical gas and suction safety Basic medical gas and suction safety training course for staff. Objective: To understand the basic principles of medical gas and suction safety in your workplace. European Pharmacopoeia and the Medicines Act define standards for the manufacturing and composition of medical gases. A medical gas is prescribed for a patient and classified as a drug. In an emergency, oxygen may be administered without a prescription, but in all cases must be recorded in the patient records. Most common medical gases Oxygen (O2) Medical air Introduction Medical gases are widely used around our hospitals and in the community and are supplied in cylinders or piped into wards and clinical areas. They are safe if handled correctly, however, misuse or mishandling can have catastrophic consequences. The purpose of this training is to raise awareness of the types of gases commonly used, the risks and hazards associated with their use and handling, identifying faulty cylinders and the appropriate action to be taken. What are medical gases? Defined as ‘‘a gas, in any form, intended for administration to a patient; either by inhalation (including ventilation), application, inflation of a body cavity or by any other means (including cardiopulmonary bypass and extracorporeal ventilation equipment)’’. Medical vacuum/suction (not actually a gas at all but is an essential medical gas service) Entonox (50 percent O2 /50 percent N2O) Nitrous oxide (N2O) Heliox 21 (79 percent He/21 percent O2) Carbon dioxide (CO2) Helium (He). You must familiarise yourself with the product data sheets for all the medical gases you use. Links to data sheets can be found on the medical gases page on the Trust Intranet. Categories of medical gases Permanent – these remain in a gaseous state under normal temperatures (eg medical air, oxygen, Heliox 21) Liquefiable – these are supplied under normal temperatures but in a liquid state (eg nitrous oxide and carbon dioxide) Cryogenic – these gases are supplied and stored at extremely low temperatures (eg liquid nitrogen and liquid oxygen). 1 Identification of medical gas cylinders The shoulder of a medical gas cylinder is colour specific to each gas: Wound cleaning or suturing Minor surgery Dressing changes Physiotherapy. Training is required to use Entonox and is provided by the Barts Health Pain Service Team. Oxygen An estimated 17.5 percent of UK hospital patients are receiving oxygen at any given time Regulations cover transport of cylinders by car – including use of TREM card, Transport Emergency Card. (Transporting cylinder recommendations can be found in medical gases section of the Intranet). About 18,000 people every day More than two million per year Essential for life in humans and animals Widespread use in hospitals and home. The majority of oxygen use is in the areas of: Critical care areas – ITU, HDU, CCU Operating theatres – intra and postoperatively Most wards – A&E, respiratory and surgical. Nitrous oxide Used predominantly by anaesthetists/dentists Its anaesthetic effects allow a reduction in the dose of other anaesthetic agents, thus reducing cost and side effects Also used to induce anaesthesia in children The commonest situation is when O2 and N2O (30:70) are used with a volatile agent. Eg one percent isoflurane Must always be used with oxygen. Medical air Piped or cylinder gas 4 bar used for patient’s needs eg delivery of nebuliser medications 7 bar used in theatres to drive medical equipment eg orthopaedic drills, saws, suction devices. Must never be administered to a patient. Heliox Used in emergency situations where the airways become partially-obstructed due to disease or foreign body Increases volume of gas into lungs due to lower density Resistance to breathing reduced. Entonox Analgesic (short term and acute pain relief), primarily used in: Midwifery Ambulances 2 MEDICAL GAS AND SUCTION SAFETY Note the batch label contains the gas cylinder expiry date – usually three years shelf life and must not be used after this date. Carbon dioxide Use in laparoscopic surgery to insufflate body cavity for increased access Also used in specialist areas eg endoscopy. Hazards Symbol Hazard Medical Gas Oxidising Oxygen, nitrous oxide and Entonox will encourage things to burn vigorously Pressure All gases supplied in cylinders. The stored pressure in medical gas cylinders can be up to 300bar Cold The storage temperature of liquid cryogenic N2 is – 196°C and O2 is – 183°C Helium Nitrogen, carbon dioxide and nitrous oxide can Asphyxiation cause oxygen deficient atmospheres Used in intra-aortic balloon pump therapy to improve coronary artery perfusion. Cylinder collar information Hazard: oxygen enrichment and oxidisation Oxygen itself is not flammable but it supports combustion and will react with most substances causing them to become highly flammable and to burn vigorously. The main hazards from oxygen-enriched environments are fire and explosion and even materials considered ‘non-flammable’ and ‘fire retardant’ can combust and burn. Oxygen enrichment can result from: Leaks from poor connections, damaged or poorly maintained equipment Using excessive flow rates of oxygen or oxidising gases Oxygen equipment left on when not required Poor ventilation in areas where oxygen or oxidising gases are used or stored. 3 An increase in oxygen concentration of only four percent doubles the risk of ignition and rate of combustion for many common items. Ignition can occur from low-energy ignition sources (eg small electrical/static sparks or light friction). At higher oxygen concentrations ignition may require so little heat or energy that combustion may appear to be spontaneous. If a ward or clinical area is oxygen-enriched, the following common items are particularly vulnerable to combustion: Hair and clothing Bed linen, mattresses, pillows and curtains Dressings, especially if medicated or ‘wet’ (treated with ointments, emollients, etc.) Surgical skin disinfectants Sanitising hand-gels and hand-rubs and any oils, greases, ointments or creams Hazard: pressure It is important to be aware of pressures at which gases are stored and used. Medical gas cylinders are filled to pressures of 127 to 300 bar (up to 150 times that of your car tyre!). Pressure itself is not necessarily dangerous. Hazardous situations occur when pressure is mishandled or improperly contained. In terms of medical gases it is appropriate to consider pressure as a form of stored energy that when released can be deadly. Exploding cylinders are able to travel in excess of 300 metres. Cardboard and paper items Chemicals and equipment used for cleaning and disinfection Electrical and electronic equipment. Best practice to minimise the risks of oxygen enrichment and oxidation fires are: Ensure hands and clothing are clean and free from oil, grease, hand-sanitising gels/rubs or hand creams Use only equipment designed specifically for use with oxygen or oxidising gases Ensure flowmeters and regulators are within their service date Use the appropriate flow rate of gas according to the method of delivery (mask, nasal ‘specs’, etc.) as prescribed Always turn gases off at the outlet source when not in use Store cylinders only in designated gas storage areas. Oxygen and nitrogen are supplied to the hospital in both gaseous and liquid form. The liquid forms (cryogenic liquid gas) are stored at less than – 180°C. Liquid gases and their vapours can cause cold burn to exposed parts of the body. Prolonged exposure can also cause frostbite, possibly leading to loss of bodily extremities such as fingers, toes and nose. Special training must be completed by all staff required to handle and work with cryogenic gases. When working with cryogenic liquids, such as filling nitrogen flasks from Dewars, personnel must wear the following personal protective equipment (PPE) designed specifically for protection from cryogenic gases: – Full-face visor Set up the cylinder for patient use before placing it close to the patient – Protective gloves Place the cylinder in an appropriately-designed holder if available – Apron Avoid placing the cylinder on the bed next to the patient if possible. 4 Hazard: temperature – Safety shoes MEDICAL GAS AND SUCTION SAFETY clinical areas. You should familiarise yourself with the piped services available in your work area. Piped gases Hazard: asphyxiation Asphyxiation may occur where the local environment has become oxygen deficient (oxygen concentration below 20 percent). Nitrogen, nitrous oxide, carbon dioxide and helium can cause this. Risk assessments should be carried out and recorded for all situations in which these gases are used and stored. These gases are supplied by plant equipment located at each of the hospital sites. The status of each system is monitored from central ‘switchboards’ through the use of master alarm panels with local alarms located in wards and departments. You should familiarise yourself with the piped gas services and the alarm panel in your work area: The following table shows the effects of low concentrations of oxygen in the local environment. Atmospheric Effects oxygen percent 21 percent to 18 percent No easily discernible symptoms detected. 18 percent to 11 percent Reduction of physical and intellectual performance. Sufferer not aware of this. 11 percent to 8 percent At 11 percent fainting may occur within a few minutes without warning. Death may result below 11 percent. 8 percent to 6 percent Fainting will occur after a very short time. Successful resuscitation possible if performed immediately. 6 percent to 0 Area Valve Service Unit (AVSU) and emergency isolation of medical gas supplies: Valves contained in locked boxes (ASVUs) are found in or around wards and clinical areas. Nursing staff should be aware of the location of each AVSU for their area. Each AVSU should be clearly labelled identifying the gas, the areas served and the number of outlets. Fainting and deep unconsciousness occurs almost immediately. Successful resuscitation unlikely. Brain damage highly probable even if resuscitation is successful. Supply and storage of medical gases Medical gases are supplied in compressed gas cylinders or piped to wards and clinical areas through complex systems collectively known as the medical gas pipeline services (MGPS). Where possible the piped gas services should always be used in preference to cylinders. The availability of piped medical gas services varies between wards and Caution Special care should be exercised when medical air and medical oxygen outlets are piped to the same bed, as the flow meters and equipment are very similar and could be confused. It is recommended that when not in use, medical air flow meters are removed from the outlet. 5 Compressed gas cylinders Compressed gas supplied in cylinders is a convenient way to deliver medical gases to patients in situations where piped services are unavailable or impractical, such as patient transfers, self-ambulatory patients and ‘crash’ trolleys. Cylinders are available in many different sizes, with a variety of valve types and can supply a variety of medical gases. For ease of reference, suppliers of compressed medical gases assign different letter codes to all their cylinders depending on size, construction and valve type. Please take a moment to look at the medical gas cylinder data chart on the Intranet. http:// bartshealthintranet/About-Us/CAGs/ClinicalSupport-Services/Clinical-physics/Clinicalengineering/Medical-Device-Training/Medicalgases.aspx Some cylinders may require the fitting of a pressureregulating device, known simply as a regulator, before they can be used. This is carried out by our trained porters. However, newer lighter-weight cylinders with ‘integral valve systems’ are available for some gases. These newer cylinders come equipped with a regulator and flowmeter built in, and have two outlets (except for Entonox which has only an integral regulator and Schrader valve). http://bartshealthintranet/About-Us/CAGs/ Clinical-Support-Services/Clinical-physics/Clinicalengineering/Documents/Entonox-Cylinders.pdf 6 Designated cylinder areas: Cylinders at ward level should be kept to a minimum They should be kept secured or in trolleys in a defined store or ‘cylinder parking area’ Those kept on ‘crash’ trolleys and anaesthetic machines must be held securely Cylinder stock levels in wards and clinics should be checked daily. Full and empty cylinders should be segregated. Ready to use cylinder stores: In theatres or A&E and ICUs it may be necessary to hold a small number of cylinders for immediate use No combustible material or non-medical gases to be stored in the same area Numbers of cylinders should be kept to 24hr use Cylinders should be stored in racks, with sufficient space to manoeuvre cylinder on and off trolleys The room must be clearly labelled with adequate prohibition and warning signs: MEDICAL GAS AND SUCTION SAFETY MEDICAL LIQUID NITROGEN All staff required to handle liquid nitrogen must be aware of the hazards and receive cryogenic safety training. Contact the Medical Device Training Team for details. Faulty cylinders Cylinders are described as faulty where the complaint is minor and the patient is not put at risk. This may be due to: Empty or part-full cylinders (not needed immediately) Faulty valve outlet Damaged outlet Minor leaks. Empty when required for immediate use Abnormal patient reaction to gas Been involved in an accident/fire. Follow the Barts Health incident reporting procedure via the Trust Intranet and inform the gas supplier. Suction The following wall suction units are found in many clinical areas throughout Barts Health. Ensure that you are familiar with what is used in your ward or clinical area and that you are trained to use any portable suction required for your patients. Policy links/further reading Barts Health NHS Trust Intranet medical gas section If a cylinder is faulty it should be removed from service and the clinical area or home. Contacts Email: Medical Device Training Team Tel: 020 359 46589 Incident cylinders BOC: www.bochealthcare.co.uk Cylinders are described as incident where the complaint is serious and the patient is considered to be put at risk. May be due to: Gas contamination Incorrect labelling Ignition damage British Thoracic Society: www.brit-thoracic.org.uk MUST DO’s Successfully complete the Medical Gas and Suction Safety quiz Following successful completion your records will be updated automatically 7