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Guideline for Prevention of Surgical Site Infection, 1999

Table 7 Surgical Wound Classification

Class I/Clean:
An uninfected operative wound in which no inflammation is encountered and the respiratory, alimentary, genital, or uninfected urinary tract is not entered. In addition, clean wounds are primarily closed and, if necessary, drained with closed drainage. Operative incisional wounds that follow nonpenetrating (blunt) trauma should be included in this category if they meet the criteria.
Class II/Clean-Contaminated:
An operative wound in which the respiratory, alimentary, genital, or urinary tracts are entered under controlled conditions and without unusual contamination. Specifically, operations involving the biliary tract, appendix, vagina, and oropharynx are included in this category, provided no evidence of infection or major break in technique is encountered.
Class III/Contaminated:
Open, fresh, accidental wounds. In addition, operations with major breaks in sterile technique (e.g., open cardiac massage) or gross spillage from the gastrointestinal tract, and incisions in which acute, nonpurulent inflammation is encountered are included in this category.
Class IV/Dirty-Infected
Old traumatic wounds with retained devitalized tissue and those that involve existing clinical infection or perforated
viscera. This definition suggests that the organisms causing postoperative infection were present in the operative field before the operation.

Garner JS1 and Simmons BP [2].

Table 8 Parameters For Operating Room Ventilation, American Institute Of Architects, 1996

Temperature 68-73°F, depending on normal ambient temperatures
Relative humidity 30%-60%
Air movement From “clean to less clean” areas
Air changes Minimum 15 total air changes per hour
Minimum 3 air changes of outdoor air per hour

American Institute of Architects.[299]

Table 9 Parameters For Flash Sterilization Cycles, Association For The Advancement Of Medical Instrumentation

Gravity-Displacement Minimum Exposure Time and Temperature
Nonporous items 3 min at 132°C (270°F)
Nonporous and porous items 10 min at 132°C (270°F)
Prevacuum Minimum Exposure Time and Temperature
Nonporous items 3 min at 132°C (270°F)
Nonporous and porous items 4 min at 132°C (270°F)

Association for the Advancement of Medical Instrumentation. [321]

Table 10 Physical Status Classification, American Society Of Anesthesiologists*

Code Patient’s Preoperative Physical Status
1 Normally healthy patient
2 Patient with mild systemic disease
3 Patient with severe systemic disease that is not incapacitating
4 Patient with an incapacitating systemic disease that is a constant threat to life
5 Moribund patient who is not expected to survive for 24 hours with or without operation
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