Surveillance definitions of CLABSI, VAP,
SSI and CAUTI:
A summary of definition criteria in
the CDC NHSN Manual
CDC National Healthcare Safety Network
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Before reporting an HAI (healthcare-associated
infection), it must satisfy the specific criteria
It is very important to use the criteria consistently to
achieve accuracy of reporting of infections
Use clinical, laboratory, pharmacy, radiology and other
diagnostic information as well as patient charts and
notes
DO NOT USE LABORATORY RESULTS ALONE!
(as these may indicate colonization only)
Physician’s diagnosis alone, in absence of other
available criteria, is acceptable except for pneumonia
HAI ( Healthcare-associated Infection)
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A localized or systemic condition resulting from adverse
reaction to the presence of an infectious agent/s or its
toxin/s
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There must be no evidence that the infection was present or
incubating at the time of admission
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The source of the infection may be endogenous or
exogenous
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Infections in infants that result from the passage through
the birth canal are HAI’s
Infections that are NOT HAI
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Complications or extensions of infections already
present on admission, UNLESS a change of pathogen or
symptoms strongly suggests the acquisition of a new
infection ( a new event)
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Infections in infants that are acquired trans-placentally,
eg. rubella, CMV, syphilis, AND become evident < 48
hours after birth.
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Re-activation of a latent infection eg. Herpes zoster
(shingles), herpes simplex, syphilis, TB
Conditions that are NOT infections
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Colonizations: presence of microbes but no adverse
clinical signs and symptoms eg. positive Microscopy on
urine report
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Inflammation in response to tissue injury or chemicals &
other non-infectious agents
CLABSI Event
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Primary bloodstream infections that are associated with
the presence of a central line (or umbilical catheter in
neonates) at the time of or within 48 hours before the
onset of the event (infection)
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There is no minimum time that the line must be in place
before the event
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LCBI (Laboratory-confirmed bloodstream infection) or
CSEP( clinical sepsis) in <1 year-olds
Location of attribution ( where the event became evident) and transfer rule( exception) – see details in
NHSN Manual.
What is a central line?
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An intravascular catheter that terminates at or close to
the heart or in one of the great vessels (aorta, pulmonary
artery, superior & inferior vena cava, brachio-cephalic
veins, internal jugular veins, subclavian veins, external
iliac veins and common femoral veins)
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Neonates: umbilical artery or vein
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Must be a lumened device through which fluids are
infused, pushed or withdrawn. May be temporary or
permanent (e.g. dialysis tunneled or implanted catheters,
including ports)
LCBI – must meet 1 of 3 criteria
Criterion 1 and 2 apply for all ages, including babies
Criterion 1:
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Pt has a RECOGNIZED pathogen cultured from 1/more blood
cultures
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AND
the organism in the blood is NOT related to an infection at
another site
Recognized pathogens: S. aureus, Enterococcus spp,
E.coli, Pseudomonas spp, Candida spp.
What if it is a common skin contaminant?
(Coagulase negative staphylococci, diptheroids, Bacillus
spp, viridans group streptococci, Propionibacterium spp,
Micrococcus & Aerococcus spp)
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It must have been identified in 2 or more blood cultures
Drawn on separate occasions ( but within 2 days of each
other) AND
Patient must have symptoms AND not related to other
site.
LCBI – must meet 1 of 3 criteria
Criterion 1 and 2 apply for all ages, including babies
Criterion 2:
 Patient has at least 1 of the following S/S:
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fever ( >38 for adults: 38 rectal or tympanic, 37 oral or 36 axilliary
for babies ), chills, or hypotension AND
S/S and pos lab results are not related to infection at another site
AND
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common skin contaminant cultured from 2 or more blood cultures
drawn at different times
LCBI (Laboratory confirmed bloodstream infection)
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Positive catheter tip cultures alone DO NOT indicate a
BSI (bloodstream infection)
Purulent phlebitis with positive culture of catheter tip and
NO or negative blood culture is reported as CVS-VASC,
not a BSI
Only report as a primary BSI if there is no other site of
infection. Secondary BSI’s are associated with an
infection at another site with the same antibiogram
CSEP ( Clinical sepsis in babies)
Criterion 3:
Patient under 1 year of age has at least one of the
following clinical S/S with no other recognized cause:
 Fever ( >38 rectal), hypothermia ( <37 rectal), apnea, or
bradycardia
AND
 Blood culture not done or no organisms detected
AND
 No apparent infection at another site
AND
 Physician commences treatment for sepsis
Temperature: 38 rectal/tympanic/temporal artery = 37 oral = 36 axillary
37 rectal/tympanic/temporal artery = 36 oral = 35 axillary
VAP (Ventilator Associated Pneumonia) event
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Diagnosed on radiological, clinical and laboratory criteria
Report PNEU’s that are ventilator-associated if the patient was intubated
and ventilated at the time of surveillance, OR within 48 hours before the
onset of the event, including the weaning period
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There is no minimum period of time the ventilator must be in place in order
for the PNEU to be considered VAP
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Location of attribution: Where patient was on the date PNEU was identified
(eg. Operating room cannot be allocated)
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Pt extubated and discharged from hospital A. Admitted hospital B next day with
PNEU. = VAP for hospital A
Transfer rule for internal transfers: if VAP develops within 48 hours of transfer, it
is attributed to the transferring location
Physician’s diagnosis ALONE is NOT acceptable, except in outbreaks of
respiratory syncitial virus, influenza or adenovirus
Definition of a ventilator
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A device to assist or control respiration continuously,
Through a tracheostomy or
By endotracheal intubation
Lung expansion devices like:
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Intermittent positive pressure breathing ( IPPB) or
Nasal positive end-expiratory pressure ( PEEP) or
Continuous nasal pos airway pressure ( CPAP or
hypoCPAP)
Are not considered ventilators UNLESS
 Delivered via tracheostomy or endotracheal intubation
(e.g. ET- CPAP)
When it is not PNEU
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When clinical status changes are due to:
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Myocardial infarction, pulmonary embolism, RDS, atalectasis,
malignancy, COAD, hyaline membrane disease, bronchopulmonary dysplasia, etc.
Intubated patients with tracheal colonization or URTI
(eg. tracheo-bronchitis) rather than early onset PNEU
Patients with tracheitis, tracheo-bronchitis, or
bronchiolitis without pneumonia are reported as BRON
Patients with lung abscess or empyema without
pneumonia are reported as LUNG
When patient is elderly, an infant, or immunocompromised, typical S/S of pneumonia may be masked
– see algorithms
Interpret sputum samples carefully – may be
contaminated with airway colonizers, eg. Candida
(However Gram stain can be an important clue)
Nosocomial pneumonia
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Characterised by onset:
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Early onset: occurs within the first 4 days of hospitalization
Moraxella catarrhalis, H. influenzae, S. pneumoniae
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including MRSA
Viruses can cause early and late onset
Yeasts, fungi, legionellae and Pneumocystis carinii usually cause
late onset
Pneumonia due to gross aspiration is considered nosocomial if it
meets any specific criteria and was not present at admission
Multiple episodes of pneumonia may occur in critically ill patients
with long ICU stays.
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Late onset: often caused by gram negative bacteria and S. aureus,
If the episode resolved and a new episode occurred, it is a new event.
Change in pathogen alone is NOT indicative of a new event – there must be new
S/S and radiographic evidence.
Refer NHSN Manual for Algorithms:P18–21 and footnotes P21 – 22 and flow diagrams: P 23 - 24
Footnotes to algorithms for VAP
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The diagnosis of HAI PNEU in non-ventilated patients is
not always easy.
Pulmonary or cardiac disease will cloud the clinical
picture, eg. Pulmonary oedema from CCF may simulate
S/S of pneumonia
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Thus serial X-rays are necessary to confirm the diagnosis.
Look at X-rays 3 days prior to the diagnosis and on days 2 and
7 after the diagnosis
Pneumonia may have a rapid onset and progression, but
it does not resolve quickly. Radiographic changes persist
for weeks
If X-rays confirm rapid resolution, then it is probably NOT
a pneumonia, but a non-infectious process like
atalectasis or CCF
Footnotes to algorithms for VAP
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X-ray terminology that may indicate PNEU:
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Purulent sputum:
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Air-space disease; focal opacification; patchy areas of increased density
Secretions from lungs / bronchi / trachea that contain > 25 neutrophils
and <10 squamous epithelial cells per low power field ( x100)
A single notation of purulent sputum or change in character of sputum is
not meaningful – changes must be documented over a 24 hour period
before they can be seen as indicative of the onset of disease
Patients with pneumonia due to viruses & mycoplasma will have
scant or watery sputum ( or sometimes muco-purulent), few S/S,
changes will only be seen on X-rays.
Infants with RSV or influenza may produce copious sputum
Patients with pneumonia due to Legionella spp, mycoplasma or
viruses: few bacteria seen on gram stain
Footnotes to algorithms for VAP
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Tachypnoea:
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Adults: > 25 breaths per minute
Prems : > 75 breaths/min
Under 2 months old: > 60 breaths / min
2-12 months: > 50 breaths / min
Children > 1 year old: > 30 breaths / min
“Rales” = crackles
An endo-tracheal aspirate is NOT a minimally
contaminated specimen, therefore, it does NOT meet the
laboratory criteria
Semi-quantitative or non-quantitative cultures of sputum
obtained by deep cough, induction, aspiration, or lavage
are acceptable
Footnotes to algorithms for VAP
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Immunocompromised patients include:
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Neutropaenia (absolute neutrophil count
Leukaemia
Lymphoma
HIV with CD 4 count < 200
Splenectomy
Early post-transplant
Cytotoxic chemotherapy
High dose steroids
< 500/cubic mm)
Algorithms for VAP
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PNU 1: an algorithm used for clinically defined
pneumonia
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PNU 2: Table 5: Pneumonia with common bacterial
or filamentous fungal pathogens and specific laboratory
findings
Table 6: Pneumonia with viral, Legionella,
Chlamydia, Mycoplasma and other uncommon
pathogens and specific laboratory findings
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PNU 3: Pneumonia in immunocompromised patients
CAUTI event
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Catheter-associated UTI’s are classified into 2 groups:
SUTI and ASB. ( excludes OUTI)
Report UTI’s that are catheter-associated if the patient
had an in-dwelling catheter at the time or within 7 days
before the onset of the event
There is no minimum time the catheter must be in situ in
order for the UTI to considered catheter-associated
Location of attribution and transfer rule as per VAP
Definition of an in-dwelling catheter
A drainage tube
 That is inserted into the urinary bladder
 Through the urethra
 Is left in place
 And is connected to a closed drainage system
 Does NOT include straight in-and-out catheters
SUTI (Symptomatic Urinary Tract Infection)
Must meet at least 1 of the following:
Criterion 1:
 Patient has at least 1 of the following S/S with no other
recognized cause:
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fever > 38, urgency, frequency, dysuria, or suprapubic
tenderness
and
Patient has positive urine culture, i.e. > 100,000
microorganisms per ml of urine with no more than 2
species of microorganism
SUTI (Symptomatic Urinary Tract Infection)
Criterion 2:
 Patient has at least 2 of the following S/S with no other
recognized cause:
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fever>38, urgency, frequency, dysuria, or suprapubic tenderness
and at least 1 of the following:
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positive dipstick for leukocyte esterase &/or nitrate
pyuria ( > 10 wbc/cubic mm)
organisms seen on gram stain of unspun urine
at least 2 urine cultures with repeated isolation of same uropathogen (
G negative bacteria or S. saprophyticus) with >100 cfu/ml in non-voided
specimens
< 100 000cfu/ml of a single uropathogen in a patient on antibiotics for
UTI
Physician diagnosis of UTI
Physician commences specific therapy for UTI
SUTI (Symptomatic Urinary Tract Infection)
Criterion 3:
 Patient under 1 year has at least one of the following S/S
with no other recognized cause:
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fever ( >38 rectal), hypothermia ( <37 rectal), apnea,
bradycardia, dysuria, lethargy, or vomiting
and
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Patient has positive urine culture, >100 000 cfu/ml with
no more than 2 species of microorganisms
SUTI (Symptomatic Urinary Tract Infection)
Criterion 4:
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Patient < 1 year has at least one of the following with no other
recognized cause:
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fever > 38 rectal, hypothermia < 37 rectal, apnea, bradycardia,
dysuria, lethargy, or vomiting
and
At least one of the following:
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Positive dipstick for leukocytes &/or nitrate
Pyuria ( > 10 wbc/ cubic mm)
Organisms seen on gram stain of unspun urine
At least 2 cultures with repeated isolation of the same uropathogen
with > 100 cfu/ml in non-voided specimens
< 100 000 cfu/ml of a single uro-pathogen in a patient on specific UTI
antibiotics
Physician diagnosis or physician commences specific UTI therapy
Comments on UTI
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A culture of a urinary catheter tip is NOT an acceptable
laboratory test to diagnose UTI
Urine cultures must be obtained appropriately:
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clean catch or catheterization
In infants, a urine culture should be obtained by bladder
catheterization or suprapubic aspiration; a bag culture is
NOT reliable.
ASB : Asymptomatic Bacteriuria
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Patient has had an indwelling catheter within 7 days
before the culture
AND
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patient has positive urine culture;
> 100 000 organisms per ml
with no more than 2 species
AND
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patient has no fever, urgency, dysuria, suprapubic
tenderness
SSI (Surgical Site Infection) Event
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Definition of an operation:
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takes place in an operating room
during a single trip to the OR( operating room)
where the surgeon makes at least one incision through the skin
or mucous membrane,
including laparoscopy
and closes the incision before the pt leaves the operating room
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An OR includes an operating room, C-section room,
interventional radiology room, cardiac cath lab
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An implant includes any non-human foreign body that is
permanently placed in a patient, including screws, mesh,
wires that are left permanently.
Superficial incisional SSI
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Infection occurs within 30 days after the operation
AND
involves only skin and subcutaneous tissue of the incision
AND
patient has at least one of the following:
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Purulent drainage
Report organisms isolated from wound swabs as follows: ( Prof Duse criteria)
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if mono-microbial growth ( one organism)
if a Strep. pyogenes ( beta haemolytic Strep Group A) isolated
if 2 organisms, must be known wound pathogens in a quantity 2+ or more
if > 2 organisms, report only the one associated with predominant growth, provided that pus cells were seen on microscopy
if 3 or more organisms, do not report unless found on a repeat specimen or wound aspirate
At least one of the following:
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pain / tenderness, localized swelling, redness/ heat and the incision is deliberately opened by surgeon and is culture pos or not
cultured.
If culture neg, it does not meet this criterion.
Diagnosis of superficial SSI by surgeon
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There are 2 types:
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SIP (primary incision) . Patient has more than 1 incision for the operation, eg. Chest incision for CABG
SIS (secondary incision) eg. Donor site incision on leg or arm for CABG
Reporting instructions for SSI
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Do not report a stitch abscess
Do not report a localized stab wound infection as SSI – it
is reported as skin or soft tissue
Cellulitis, by itself, does not meet the criteria for SSI
Infected circumcision site is reported as CIRC
Infected burn wound is reported as BURN and not SSI
If incisional site infection extends into fascial or muscle
layers, report as deep ( DIP / DIS)
Deep Incisional SSI
Infection occurs within 30 days if no implant or
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Within 1 year if implant is placed and infection is related to the
operative procedure
AND
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Involves deep soft tissues ( fascia / muscle)
AND
Patient has at least ONE of the following:
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Purulent drainage from deep incision, but not organ / space
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Deep incision spontaneously dehisces or
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Is opened by surgeon and
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Is culture-pos or not cultured when the pt has at least one of the
following S/S:
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Fever>38, localized pain/tenderness
( A culture-negative finding does not meet this criterion)
An abscess or other evidence of infection found by direct exam /
x-rays / histopathologic exam
Diagnosis by a surgeon
2 Types: DIP (primary incision), and DIS ( secondary incision)
Organ / space SSI
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Involves any part of the body ( including skin incision,
fascia, muscle layer) that is opened and manipulated
during an operative procedure
Specific additional sites are assigned to organ/space
SSI’s to identify the location e.g.
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Appendectomy with sub-diaphragmatic abscess = SSI – IAB
(intra-abdominal specific site)
SSI - BONE
( Table on P 37, NHSN Manual)
Organ / space SSI
Infection occurs within 30 days after the operation if no implant
and within 1 year if implant is placed & infection is related to
operative procedure
AND
Infection involves any part of the body, excluding skin incision,
fascia, muscle) that is opened or manipulated during the operation
AND
Patient has at least one of the following:
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Purulent drainage from a drain placed through a stab wound into the
organ / space
Organisms obtained from aseptically obtained culture of fluid or tissue
in the organ / space
Abscess found on direct examination or x-rays or histopathology
examination
Diagnosis by surgeon or physician