Microbiology

'O' Choosing the appropriate prophylactic antimicrobial relies on anticipating which organisms will be encountered during the operation. SSIs associated with extra-ab dominal operations are the result of skin flora organisms in nearly all cases. These organisms include gram-positive cocci, with S. aureus and Staphylococcus epiderm-idis being among the most frequently isolated SSI pathogens according to the National Nosocomial Infections Surveillance System (NNIS)5 (Table 85-2). Streptococcus spp. and other gram-positive aerobes may also be implicated.

Table 85-1 National Red Cross Wound Classification, Risk of SSI, and Antibiotic Indication

Classification Description

SSI Antibiotic Risk Prophylaxis

Clean

Clean-contaminated

Contaminated

Dirty

No acute inflam- Low mation or transection of Gl, oropharyngeal. GU, biliary, or respiratory tracts; elective case, no technique break

Controlled opening of aforementioned tracts with minimal spillage or minor technique break; clean procedures performed emergently or with major technique breaks

Acutc, nonpurulent High inflammation present; major spillage or technique break during clean-contaminated procedures

Obvious pre-existing — infection present (abscess, pus, or necrotic tissue

Indicated

Medium Indicated

Indicated

Not indicated; antibiotics used for treatment

Intra-abdominal operations involve a diverse flora with the potential for polymi-crobial SSIs. Escherichia coli make up a large portion of bowel flora and are frequently isolated as pathogensaccording to the NNIS.5 Other entericgram-negative bacteria, as well as anaerobes (especially Bacteroides spp.), may be encountered during intra-abdominal operations.

Candida albicans is being implicated as the cause of a growing number of SSIs. According to the NNIS, from 1991 to 1995, the incidence of fungal SSIs rose from 0.1 to 0.3 per 1,000 discharges.5 Increased use of broad-spectrum antimicrobials and rising prevalence ofimmunocompromised and human immunodeficiency virus-infected individuals are factors in fungal SSIs. Despite this increase, antifungal prophylaxis for surgery is not currently recommended.

The Prevention and Treatment of Headaches

The Prevention and Treatment of Headaches

Are Constant Headaches Making Your Life Stressful? Discover Proven Methods For Eliminating Even The Most Powerful Of Headaches, It’s Easier Than You Think… Stop Chronic Migraine Pain and Tension Headaches From Destroying Your Life… Proven steps anyone can take to overcome even the worst chronic head pain…

Get My Free Audio Book


Post a comment