Laparoscopic surgery required expensive surgical instruments that are inherently difficult t clean. Steam sterilization in an autoclave is not possible for many instruments and Ethylene oxide sterilization is either unavailable or unsuitable between operations in many instances. The commonest method seems to be the use of prolonged exposure to Formaldehyde gas in a chamber or immersion in Glutataldehyde. A review of the literature regarding this is presented.

On study (1) on cleaned and sterilized instruments has shown residual organic debris on 87% of instruments that were considered clean. This was done on reusable laproscopic, reused disposable laparoscopic and conventional surgical instruments. Interestingly the amount of residue found on reusable laparoscopic and reused disposable laparoscopic instruments was similar. Following washing and ultrasonic cleaning one study (2) demonstrated bacterial growth of >100 Colony Forming Units (CFU) that disassembly of instruments before cleaning following by re-assembly leads to more tough sterilization than when the instruments are not dis-assembled.

It is recommended that certain laparoscopic instruments (such as optics that cannot be sterilized in an autoclave should receive a high level of disinfection (4). Decontamination of instruments should be done immediately after surgery by thorough washing and the use of an ultrasonic cleaner (5). The latter are now easily available in India. Instruments that can be taken apart must be disassembled prior to washing.

Formaldehyde has a broad spectrum of action on microorganisms. A number of studies have shown that with contact time of 60-180 minutes, formaldehyde at .2% will only sanitize. Formaldehyde at 2% will disinfect.

Formaldehyde at 2% will sterilize. Formaldehyde works best at a relative humidity of >70%-80% and at higher temperatures, and its activity against spores and acid fast bacilli is slow (6). The use of Glutaraldehyde is effective, but the manufacturer's instructions regarding pH, self life, and time for disinfection or sterilization must be followed.

It is worth noting that the agent causing creutzfeldtJokob disease in resistant to sterilization by boiling, ultraviolet irradiation, ionizing radiation, 70% ethanol plus formaldehyde vapour, glutaraldehyde, 4% formaldehyde (10% formalin, as used to preserve pathologic specimens) and Ethylene Oxide.

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