|
Definitions for the Terms
Bacteremia, Sepsis, Severe Sepsis,
Septic Shock, and Other Related
Disorders
A 1992 American
College of Chest Physicians/Society
of Critical Care Medicine consensus
panel defined the following terms
which are relevant to the discussion
of septic shock:
Infection:
Infection is a microbial phenomenon
characterized by an inflammatory
response to the presence of
microorganisms or the invasion of
normally sterile host tissue by
those organisms.
Bacteremia:
Bacteremia refers to the presence of
viable bacteria in the blood.
Systemic
inflammatory response syndrome:
Systemic inflammatory response
syndrome (SIRS) is a widespread
inflammatory response to a variety
of severe clinical insults. This
syndrome is clinically recognized by
the presence of two or more of the
following:
- Temperature
>38°C or <36°C
- Heart rate
>90 beats/min
- Respiratory
rate >20 breaths/min or PaCO2 <32
mmHg
- WBC >12,000
cells/mm3, <4000 cells/mm3, or >10
percent immature (band) forms
Sepsis: Sepsis is
the systemic response to infection.
Thus, in sepsis, the clinical signs
describing SIRS are present together
with definitive evidence of
infection.
Severe sepsis:
Sepsis is considered severe when it
is associated with organ
dysfunction, hypoperfusion, or
hypotension. The manifestations of
hypoperfusion may include, but are
not limited to, lactic acidosis,
oliguria, or an acute alteration in
mental status.
Septic shock:
Septic shock is sepsis with
hypotension despite adequate fluid
resuscitation. It includes perfusion
abnormalities such as lactic
acidosis, oliguria, or an acute
alteration in mental status.
Patients receiving inotropic or
vasopressor agents may not be
hypotensive at the time that
perfusion abnormalities are
measured.
Hypotension:
Hypotension is defined as a systolic
BP of <90 mmHg or a reduction of >40
mmHg from baseline, in the absence
of other causes for the fall in
blood pressure.
Multiple organ
dysfunction syndrome: Multiple organ
dysfunction syndrome (MODS) refers
to the presence of altered organ
function in an acutely ill patient
such that homeostasis cannot be
maintained without intervention. The
multiple organ dysfunction syndrome
is classified as either primary or
secondary.
- Primary
MODS is the result of a
well-defined insult in which organ
dysfunction occurs early and can
be directly attributable to the
insult itself (eg, renal failure
due to rhabdomyolysis).
- Secondary
MODS is organ failure not in
direct response to the insult
itself, but as a consequence of a
host response. In the context of
the definitions of sepsis and
SIRS, MODS represents the more
severe end of the spectrum of
severity of illness characterized
by SIRS/sepsis.
|
Principles of Critical Care, Third Edition, by J. Hall
3th edition (June 24, 2005)
Textbook Of Critical Care, Fifth Edition, by M. Fink
5th Bk&Cdr edition (January 10, 2005)
|
