Letter. Sterilization of surgical instruments
May I mention another method of disinfection not listed in your recent article (No. 19, 1996), which I have used in eye camps in Pakistan. This is the use of steam without an autoclave. One uses a deep sterilizer only partly filled with water, with trays of eye instruments suspended in a rack above the water level. We have used either bottled gas or electricity for heating; I prefer the former in the absence of mains electricity as one can then provide for the lighting with a much smaller generator. Small instruments soon heat up in the steam above the closed sterilizer, and are given at least five minutes. There are several advantages: the steam is largely free of any impurities in the water; the instruments may dry more quickly than after boiling; and there does not appear to be any problem from blunting. Some surgeons and eye theatre nurses will question the efficacy of the method, and demand a longer exposure to steam, but I have not met infection definitely attributable to the method. I would be interested to hear of the experience of others.
The steaming method [that is without pressure] is, a popular and relatively effective method of disinfection in developing countries Please note – it does not sterilize.
It is important to:
- Maintain the level and boiling point of the water.
- Ensure the water is at boiling point before placing the instruments in the steamer – ‘heating up’ is not sufficient!
- Steam the instruments for a minimum of 10 minutes and preferably 20.
- Cover the receptacle.
The questionable access of steam to the lumens of instruments is a serious concern.
The steaming method is sometimes chosen only in an attempt to avoid blunting of instruments. There is no other direct benefit of steaming. Rather, adding 2% soda to the water in the boiling method is advised.
1 Brouwer MR, Hardus, PLL. Sterilization of ophthalmological instruments. Tropical Doctor 1988; 18: 174-6.
2 Hughes RA. Sterilization of Instruments in Isolated Hospitals. Tropical Doctor 1982; 12: 87.
References to steaming without pressure would be welcomed. Despite an extensive literature search none have been traced. We welcome correspondence from our readers regarding experience and opinion in this area.