Surgical Care at the District Hospital
Part 1 2 3 4 5 6 Primary Trauma Care Manual
Resusciation and Anaesthesia
Resuscitation and Preparation for Anaesthesia and Surgery
Management of emergencies and cardiopulmonary resuscitation
Other conditions requiring urgent attention
Intravenous access
Fluids and drugs
Drugs and resuscitation
Preoperative assessment and investigations
Anaesthetic issues in the emergency situation
Important medical conditions for the anaesthetist
Practical Anaesthesia
General anaesthesia
Anaesthesia during pregnancy and for operative delivery
Pediatric anaesthesia
Conduction anaesthesia
Specimen anaesthetic techniques
Monitoring the anaesthetized patient
Postoperative management
Anaesthetic infrastructure and supplies
Equipment and supplies for different level hospitals
Anaesthesia and oxygen
Fires, explosions and other risks
Care and maintenance of equipment
Fires, Explosions and Other Risks
 




All operating room staff should be aware of the risks of fire or explosion as a result of the use of anaesthetic vapours. It is important to distinguish between gas mixtures that can burn and those that are explosive. Explosions are much more dangerous to both staff and patients. Of the inhalational anaesthetics mentioned in this book, only ether is flammable or explosive in clinical concentrations:

:: Mixtures of ether and air in the concentrations used for anaesthesia are flammable
:: Mixtures of ether and air (whatever the concentration) are not explosive
:: Mixtures of ether with oxygen or nitrous oxide are explosive
:: Other substances used in the operating room, such as alcoholic skin preparations, also present a risk of fire or even explosion in the presence of high concentrations of oxygen.


There is no site within the draw-over apparatus or breathing system where a fire or explosion could start. The point of risk is therefore the place where the patient’s expired gas enters the room – or at any point where anaesthetic gas accidentally leaks into the room from the apparatus. If you are using 3–5% ether as an anaesthetic in combination with a muscle relaxant, it is likely that the ether concentration in the patient’s expired gas will be less than the lowest flammable concentration (2%).

If ether is used on a compressed gas machine (Boyle’s machine), the gases are always explosive.

When flammable gases are in use, the most likely sources of combustion in the operating theatre are the surgical diathermy machine and other electrical apparatus. Static electricity is unlikely to start a fire, but may trigger an explosion if an oxygen-rich gas mixture is present.

To minimize the risk of explosion, never allow the simultaneous use of diathermy on a patient anaesthetized with ether. If one of these techniques must be used for the benefit of the patient, the other must not be allowed.

If possible, your operating room and equipment should be of the antistatic type. This is important in a dry climate, but less so in a humid one where a natural coating of moisture on objects prevents the buildup of static.

Electrical sockets and switches should either be spark-proof or be situated at least 1 metre above floor level. The patient’s expired gases should be carried away from the expiratory valve down wide-bore tubing at least to the floor (ether is heavier than air) or out of the operating room. Make sure that no-one stands on the hose and that there is nothing that could trigger combustion near the end of the tubing. If you use oxygen enrichment during induction, but not surgery, the patient’s expired gas will cease to be explosive within 3 minutes of stopping the addition of oxygen.

No potential cause of combustion or source of sparking should be allowed within 30 cm of any expiratory valve through which a potentially flammable or explosive mixture is escaping.



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