Summary: Bacteremia is under active microbiological surveillance at JHH.
All positive blood cultures are forwarded to HEIC for review. Bacteremia is an infection of the blood stream that can progress to a life threatening sepsis. Bacteremia can originate from bacterial infection at any site, and is the common "terminal pathway" of bacterial disease progression (Ferguson, 1996).
Because it may originate from a range of initial conditions, diagnosis of bacteremia may be complicated.
A study of bacteremia in a community hospital found that bacteremia had doubled from 4.59/1,000 admissions in 1980-1983 to 9.44/ 1,000 admissions in 1990-1993 (Steinberg, 1996).
Sepsis is the thirteenth leading cause of death in the U.S. and the leading cause of death for patients in intensive care units (ICU) (Ackerman, 1994).
Despite advances in technology about half of patients with sepsis will die (Spooner, 1992, Arizmendi, 1990).
The inability to reduce sepsis mortality may be due to increases in the underlying health risks of the patient population.
Immunosuppression, invasive procedures, very young or very old age increase the risk of mortality (Ackerman, 1994) .
Eligible Patients
All patients admitted to the hospital
Surveillance Definition of Infection
NOSOCOMIAL BACTEREMIA must meet at least one of the following three criteria:
Criterion 1: Bacteremia caused by a recognized pathogen
Patient has a recognized pathogen cultured from one or more blood cultures obtained on or after hospital day 2. (Same pathogen not cultured from blood prior to hospital day 2). See {recurrent bacteremia} and {calculating hospital day 2}.
Criterion 2: Bacteremia caused by common skin flora. (e.g. coagulase-negative staphylococci or Corynebacterium bacillus, Micrococcus, or Propionibacterium species)
Patients must be culture positive and symptomatic to be considered bacteremic.
Culture positive: Patients must have either:
- two blood cultures positive for the same organism within 5 days or
one blood culture and a vascular catheter culture-both positive for the same organism within 5 days
Symptomatic: within 24 hours (before or after) the positive blood culture. Patients must have either
- a fever (temp. >38°C), or
- chills or hypotension (systolic BP <90 mmHg or oliguria <20 cc/hr)
Criterion 3: Patients less than one year old, bacteremia caused by common skin flora. (e.g. coagulase-negative staphylococci or Corynebacterium bacillus, Micrococcus, or Propionibacterium species)
Patients must be culture positive and symptomatic to be considered bacteremic.
Culture positive:
Patients must have either:
- two blood cultures positive for the same organism drawn on separate occasions, or
- one positive blood cultre from a patient with an intravenous line, and physician institutes appropriate antimicrobial therapy
Symptomatic:
Patients must have one of the following three sypmtoms
- fever (> 38° C) or hypothermia (<37° C)
- apnea
- bradycardia
Definitions
|
Nosocomial |
not incubating at time of admission |
|
Identical organisms |
Identical organisms are defined as the same genus and species with an antimicrobial susceptibility difference of < 1 tube dilution for each antibiotic tested (use the most resistant organism to list) or as tested by DNA analysis. Antimicrobial susceptibility differences of > 2 tube dilutions are considered different organisms. |
|
Recurrent bacteremia |
bacteremia that recurs with the same organism after two weeks will be documented as a new infection (no positive blood cultures for that organism in the previous two weeks).
positive cultures for different organisms within the same 72 hr. period are recorded as a single bacteremic event. |
|
Primary bacteremia |
Confirmed bloodstream infection without positive cultures from another site. |
|
Secondary bacteremia |
Secondary bacteremia is a culture-confirmed bloodstream infection (BSI) when there is a positive culture with the same species ( antibiogram for epidemiologically important resistance patterns) from another body site.
exception: bacteremias caused by common skin flora are considered secondary only if their is evidence of infection with the common skin flora at another site. |
E. Nosocomial infections are those that are acquired during a hospital stay. Thus, bacteremias at the time of admission and those occuring through Day=1 are not considered nosocomial. After the begining of Day=2, a positive blood culture would indicate a nosocomial bacteremia.
For patients re-admitted rapidly after a recent hospitalization or procedure (less than 2 days later) bactermias occuring within the first two days will be counted as nosocomial. However, in the case of patients who are re-admitted with the same organism, the second bacteremic event is not counted as a new case.
For Example
January, 1999
|
Mon |
Tues |
Weds |
Thurs |
Friday |
Saturday |
Sunday |
| |
|
|
|
1
Admitted
Day=0 |
2
Day=1 |
3
Positive Blood Culture
Day=2 |
|
4
Day=3 |
5
Day=4 |
6
Day=5 |
7
Discharged
Day=6 |
8 |
9
Re-Admitted
Day=0 |
10
Positive Blood Culture
Same Organism
Day=1 |
|
11
Day=3 |
12
Discharged
Day=4 |
13 |
14
Re-Admitted
Positive Blood Culture
Different Organism
Day=0 |
15 |
16 |
17 |
Assuming all other criteria are met, the bacteremia occuring January 3rd would be considered nosocomial. The bacteremia on January 10 would not be counted as new case, but would be treated as a recurrence o f the initial bacteremia. The third bacteremia, occuring January 14, would be counted as a second episode of nosocomial bacteremia.
