Surgical infections
Definitio
• Surgical infections = infections that are surgically treatable (primary surgical
infection) or appear as consequence of medical procedures
• Surgical infection is an infection that:
(1) is unlikely to respond to nonsurgical treatment (it usually must be excised or
drained) and occupies an unvascularized space in tissue or
(2) occurs in an operated site
Classification (1)
Acute \ Subacute \ Chronic
Localised \ Systemic
Etiology:
•Bacterial •Viral •Fungal •Parasitic etc.
Single germ -Pluribacterial
Nonspecific -Specific (TB, actinomicosis etc.)
Etiology
Determinant factors:
•Microorganism
(1) microbial pathogenicity and number,
(2) host defenses,
(3) the local environment, and
(4) surgical technique(for postoperative infection).
1
, Pathogenesis - 1
-Primum movens – bacterial agression produces a local and systemic reaction
-Tissue necrosis is always present in localised infection
-Inflammation is the cornerstone: Inflammation is a protective response
-intended to eliminate the initial cause of cell injury as well as the necrotic
cells and tissues resulting from the original insult.
Pathogenesis - 2
For localised infection:
•an infectious agent
•a susceptible host
•a closed, unperfused space
Pathophysiology - 1
Inflammation:
• Local vasodilation
• Increased vascular permeability
• PMN migration
•Mediators (kinins, complement, clotting factors, inflammation factors)
Influencing factors:
• Virulence and germ species
• Germ inoculation quantity
• Microbial association
•The host
Infection course:
•Local:
2
Definitio
• Surgical infections = infections that are surgically treatable (primary surgical
infection) or appear as consequence of medical procedures
• Surgical infection is an infection that:
(1) is unlikely to respond to nonsurgical treatment (it usually must be excised or
drained) and occupies an unvascularized space in tissue or
(2) occurs in an operated site
Classification (1)
Acute \ Subacute \ Chronic
Localised \ Systemic
Etiology:
•Bacterial •Viral •Fungal •Parasitic etc.
Single germ -Pluribacterial
Nonspecific -Specific (TB, actinomicosis etc.)
Etiology
Determinant factors:
•Microorganism
(1) microbial pathogenicity and number,
(2) host defenses,
(3) the local environment, and
(4) surgical technique(for postoperative infection).
1
, Pathogenesis - 1
-Primum movens – bacterial agression produces a local and systemic reaction
-Tissue necrosis is always present in localised infection
-Inflammation is the cornerstone: Inflammation is a protective response
-intended to eliminate the initial cause of cell injury as well as the necrotic
cells and tissues resulting from the original insult.
Pathogenesis - 2
For localised infection:
•an infectious agent
•a susceptible host
•a closed, unperfused space
Pathophysiology - 1
Inflammation:
• Local vasodilation
• Increased vascular permeability
• PMN migration
•Mediators (kinins, complement, clotting factors, inflammation factors)
Influencing factors:
• Virulence and germ species
• Germ inoculation quantity
• Microbial association
•The host
Infection course:
•Local:
2
