Surgical site infection 2015

ANTHONY R. PEREZ, MD,MHA,FPCS,FACS,FPSGS,FPALES
Presented during the 21st PHICS Convention, 28-29 May 2015

 TO DESCRIBETHE CURRENT
EPIDEMIOLOGY OF SURGICAL SITE
INFECTIONS ( SSI)
 TO DISCUSS INFECTION CONTROL
MEASURESTHAT SHOULD BETAKENTO
MINIMIZETHE RATE OF SURGICAL SITE
INFECTIONS

 Infections of the tissues, organs, or spaces
exposed by surgeons during performance of
an invasive procedure.
 Infections occurring up to 30 days after
surgery (or up to one year after surgery in
patients receiving implants) and affecting
either the incision or deep tissue at the
operation site.

 Among the top 3 most common hospital
acquired infections.
 The most common hospital acquired
infection among surgical patients
▪ 2/3 incisional
▪ 1/3 organs/spaces

 SSISARETHE MOST COMMON NOSOCOMIAL
INFECTION, ACCOUNTING FOR 38 PERCENT
OF NOSOCOMIAL INFECTIONS.
 THE OVERALL RISK OF SSI IS LOW
 SSI DEVELOP IN 2TO 5 PERCENT OFTHE
MORETHAN 30 MILLION PATIENTS
UNDERGOING SURGICAL PROCEDURES EACH
YEAR
 1 IN 24 PATIENTSWHO UNDERGO INPATIENT
SURGERY INTHE UNITED STATES HASA
POSTOPERATIVE SSI

 SSI RATES IN AMBULATORY SURGICAL
SETTINGSARE RELATIVELY LOW
 ONE STUDY NOTED OVERALL RATES AT 14
AND 30 DAYS OF 3.1 AND 4.8 PER 1000
PROCEDURES

 SURGICAL SITE INFECTIONS (SSIS) ARE
ASSOCIATEDWITH SUBSTANTIAL MORBIDITY
AND MORTALITY, PROLONGED HOSPITAL
STAY,AND INCREASED COST.
 AMONG PATIENTS DYING INTHE POST
OPERATIVE PERIOD, DEATH RELATEDTO SSI
IN OVER 75% OF CASES
 IN ONE CASE CONTROLLED STUDY USING
ORTHOPEDIC PATIENTS, SSI LEDTO MEDIAN
INCREASE IN HOSPITAL STAY OF 14 DAYS, 2X
INCREASE IN RATE OF REHOSPITALIZATION
AND INCREASEDTOTALCOST > 300%

 Local data is lacking
 Surgical Site Infection Data
 PCS Committee on Surgical Infection

Philippine Society of
General Surgeons
Metro Manila Chapter

SURGICAL SITE INFECTION
RATE

 Incisional SSI
 Superficial – skin and subcutaneous
 Deep – deeper soft tissue e.g. fascia, muscles
 Organ/Space SSI
▪ involve any part of the anatomy (e.g. organ or space) other
than incised body wall layers, that was opened or
manipulated during an operation

Subcutaneous
tissue
Skin
Superficial
incisional
SSI
Involves only
skin or
subcutaneous
tissue
of the incision

Subcutaneous
tissue
Skin
Superficial
incisional
SSI
Involves
the deep
soft tissue
e.g., fascia
and muscle
layers)
Deep soft tissue
(fascia & muscle)
Deep
incisional SSI

Subcutaneous
tissue
Skin
Superficial
incisional
SSI
Involves any
part of the
anatomy,
other than
the incision,
which was
opened or
manipulated
during the
operation Deep soft tissue
(fascia & muscle)
Deep
incisional SSI
Organ/space Organ/space
SSI

 National Nosocomial Infection Surveillance of
the CDC
 Standardized surveillance criteria for
accuracy and consistency in reporting

 OCCURS WITHIN 30 DAYS AFTERTHE OPERATION
AND
 INVOLVES ONLY SKIN OR SUBCUTANEOUS
TISSUE
AND AT LEAST ONE OFTHE FOLLOWING:
 PURULENT DRAINAGE
 ORGANISMS ISOLATED
 SIGNS OR SYMPTOMS OF INFECTION AND
SUPERFICIAL INCISION IS DELIBERATELY OPENED BY
SURGEON
 DIAGNOSIS OF SUPERFICIAL INCISIONAL SSI BYTHE
SURGEON

 OCCURS WITHIN 30 DAYS AFTERTHE OPERATION OR WITHIN
1YEAR IF IMPLANT IS IN PLACE ANDTHE INFECTION APPEARS
TO BE RELATEDTOTHE OPERATION
AND
 INVOLVES DEEP SOFTTISSUES (E.G., FASCIAL AND MUSCLE
LAYERS)
 PURULENT DRAINAGE FROMTHE DEEP INCISION
 A DEEP INCISION SPONTANEOUSLY DEHISCES OR IS
DELIBERATELYOPENED BY A SURGEON WITH SIGNS AND
SYMPTOMSOF INFECTION
 AN ABSCESSOR OTHER EVIDENCEOF INFECTION INVOLVINGTHE
DEEP INCISION IS FOUND ON DIRECT EXAMINATION, DURING
REOPERATION,OR BY HISTOPATHOLOGIC OR RADIOLOGIC
EXAMINATION
 DIAGNOSIS OF A DEEP INCISIONAL SSI by a surgeon

 OCCURS WITHIN 30 DAYS AFTERTHE OPERATION OR WITHIN
1YEAR IF IMPLANT IS IN PLACE ANDTHE INFECTION APPEARS
TO BE RELATEDTOTHE OPERATION
AND
 INFECTION INVOLVES ANY PART OFTHE ANATOMY (E.G.,
ORGANS OR SPACES), OTHERTHANTHE INCISION, WHICHWAS
OPENED OR MANIPULATED DURING AN OPERATION
 PURULENT DRAINAGE FROM A DRAINTHAT IS PLACEDTHROUGH
A STABWOUND INTOTHE ORGAN/SPACE.
 ORGANISMS ISOLATED
 AN ABSCESSOR OTHER EVIDENCEOF INFECTION INVOLVINGTHE
ORGAN/SPACETHAT IS FOUNDON DIRECT EXAMINATION,
DURING REOPERATION,OR BY HISTOPATHOLOGIC OR
RADIOLOGIC EXAMINATION
 DIAGNOSIS OF AN ORGAN/SPACE SSI BY A SURGEON

 MICROBIAL CONTAMINATION OF THE
SURGICAL SITE IS A NECESSARY
PRECURSOR OF SSI

 QUANTITATIVELY, IT HAS BEEN SHOWNTHAT
IF A SURGICAL SITE IS CONTAMINATEDWITH
>105 MICROORGANISMS PER GRAM OF
TISSUE,THE RISK OF SSI IS MARKEDLY
INCREASED.
 THE DOSE OF CONTAMINATING
MICROORGANISMS REQUIREDTO PRODUCE
INFECTION MAY BE MUCH LOWERWHEN
FOREIGN MATERIAL IS PRESENT ATTHE SITE.

Dose of bacterial
contamination
Virulence
Resistance of the
host patient
Risk of
surgical site
infection
X =

 Clean wounds
 Class I
 no infection is present
 no hollow viscus is entered
 only skin microflora potentially contaminate the
wound
 Class ID
 wounds are similar except that a prosthetic device
(e.g., mesh or valve) is inserted

 Clean/contaminated wounds
 Class II
 a hollow viscus such as the respiratory,
alimentary, or genitourinary tracts with
indigenous bacterial flora is opened under
controlled circumstances
 without significant spillage of contents

 Contaminated wounds
 Class III
 open traumatic wounds encountered early after injury
 those with extensive introduction of bacteria into a
normally sterile area of the body due to major breaks
in sterile technique (e.g., open cardiac massage),
 gross spillage of viscus contents such as from the
intestine, or incision through inflamed, albeit
nonpurulent, tissue

 Dirty wounds
 Class IV
 traumatic wounds with significant delay in
treatment and in which necrotic tissue is present
 those created in the presence of overt infection
(purulent material)
 those created to access a perforated viscus with
high degree of contamination

Wound Classification Expected SSI Rates
Clean (class I) 1-4%
Clean/contaminated (class II) 6-9%
Contaminated (class III) 13-20%
Dirty (class IV) 40%

3 independent variables associated with
SSI risk
 Contaminated or dirty/infected wound
classification
 ASA score > 2
 Length of operation > 75th percentile of the specific
operation being performed

ASA Class
Class I A patient in normal health
Class II
A patient with mild systemic disease resulting in no functional
limitations
Class III
A patient with severe systemic disease that limits activity, but is
not incapacitating
Class IV
A patient with severe systemic disease that is a constant threat to
life
ClassV A moribund patient not likely to survive without the operation
ClassVI
A patient already declared brain dead whose organs are being
removed for donor purposes

Operation T Point (hrs)
Coronary artery bypass graft 5
Bile duct, liver, or pancreatic surgery 4
Craniotomy 4
Head and neck surgery 4
Colonic surgery 3
Joint prosthesis surgery 3
Vascular surgery 3
Abdominal or vaginal hysterectomy 2
Ventricular shunt 2
Herniorrhaphy 2
Appendectomy 1
Limb amputation 1
Cesarean section 1

Wound Class All NNIS 0 NNIS 1 NNIS 2 NNIS 3
Clean 2.1 % 1.0% 2.3% 5.4% N/A
Clean
contaminated
3.3% 2.1% 4.0% 9.5% N/A
Contaminated 6.4% N/A 3.4% 6.8% 12.8%
Dirty/Infected 7.1% N/A 3.1% 8.1% 13.2%
All 2.8% 1.5% 2.9% 6.8% 13%

 Patient characteristics
 Operation characteristics
 Preoperative
 Intraoperative
 Postoperative

 Age
 Diabetes
 Smoking
 Steroid Use
 Malnutrition
 Obesity
 Altered immune
response
 Prolonged
preoperative stay
 Preoperative
colonization with S.
aureus
 Perioperative
transfusion
 Coexistent infection at
a remote body site

 Duration of surgical
scrub
 Maintain body temp
 Skin antisepsis
 Preoperative shaving
 Duration of operation
 Antimicrobial
prophylaxis
 Operating room
ventilation
 Inadequate
sterilization of
instruments
 Foreign material at
surgical site
 Surgical drains
 Surgical technique
 Poor hemostasis
 Failure to obliterate
dead space
 Tissue trauma

 Significant relationship between increasing
levels of HgA1c and SSI rates
 Increased glucose levels (>200 mg/dL) in the
immediate postoperative period (<48 hours)
were associated with increased SSI risk
 Delay elective procedures until after sugar
levels have been controlled

 Cigarette smoking was an independent risk
factor for SSI
 Nicotine use delays primary wound healing
 Cessation of smoking is recommended

 Patients who are receiving steroids or other
immunosuppressive drugs may be
predisposed to developing SSI but the data
supporting this relationship are
contradictory.

 NUTRITIONAL SUPPORT IN
MALNOURISHED PATIENTS UNDERGOING
MAJOR SURGERY IS INITIATEDTO
DECREASE MAJOR MORBIDITIES
ASSOCIATEDWITH NUMEROUS
POTENTIALCOMPLICATIONS LIKE FASCIAL
DEHISENCE,ANASTOMOTIC LEAKS, ETC.

 Theoretically, severe malnutrition is
associated with postoperative nosocomial
infections, impaired wound healing dynamics
or death.
 Preoperative and/or postoperative
“nutritional therapy” has not been
demonstrated to reduce incisional SSI risk.

 Blood transfusion apparently doubles the risk
for SSI.
However, several confounding variables may
have influenced the reported association.
 There is currently no scientific basis for
withholding necessary blood products from
surgical patients as a means of SSI risk
reduction.

 Preoperative antiseptic shower or bath
decreases skin microbial colony counts.
 Chlorhexidine reduced bacterial colony
counts ninefold.
 They have not definitively been shown to
reduce SSI rates

 Preoperative hair removal by any means was
associated with increased SSI rates.
 No hair should be removed unless necessary.

 Increased SSI risk associated with shaving has
been attributed to microscopic cuts in the
skin that later serve as foci for bacterial
multiplication.
 Clipping hair has been associated with a
lower SSI risk than shaving

 Most commonly used agents:
 Iodophors (e.g., povidone-iodine)
 Acohol-containing products
 Biguanides (chlorhexidine gluconate)

 Alcohol is readily available, inexpensive, and
remains the most effective and rapid-acting
skin antiseptic.
 Aqueous 70% to 92% alcohol solutions have
germicidal activity against bacteria, fungi,
and viruses, but spores can be resistant.
 One potential disadvantage is its
flammability.

 BOTH CHLORHEXIDINE GLUCONATE AND
IODOPHORS HAVE BROAD SPECTRA OF
ANTIMICROBIAL ACTIVITY
 CHLORHEXIDINE GLUCONATEACHIEVED GREATER
REDUCTIONS IN SKIN MICROFLORA AND ALSO
HAD GREATER RESIDUAL ACTIVITYAFTER A SINGLE
APPLICATION
 POVIDONE-IODINE EXERT A BACTERIOSTATIC
EFFECT AS LONGASTHEY ARE PRESENT ONTHE
SKIN, BUT MAY BE INACTIVATED BY BLOOD OR
SERUM PROTEINS.

 NO STUDIES HAVE ADEQUATELY
ASSESSEDTHE COMPARATIVE EFFECTS OF
THESE PREOPERATIVE SKINANTISEPTICS
ON SSI RISK INWELL-CONTROLLED,
OPERATION-SPECIFIC STUDIES

 THE OBJECTIVE -TO ELIMINATETHE
TRANSIENT MICROORGANISMSAND
INHIBITTHE GROWTH OF RESIDENT FLORA
UNDERTHE GLOVED HAND ATTHE
BEGINNING OF SURGERY UNTILTHE END
OFTHE OPERATION.

 ABOUT 18% OF GLOVES HAVETINY
PUNCTURESAFTER SURGERY,AND MORE
THAN 80% OF CASES GO UNNOTICED BYTHE
SURGEON.
 SURGICAL HAND ANTISEPSISAIMSTO
REDUCETHE RELEASE OF SKIN BACTERIA
FROMTHE HANDS OFTHE SURGICALTEAM
INTOTHE OPENWOUND IN CASE OF AN
UNNOTICED PUNCTURE OFTHE SURGICAL
GLOVE.

 RINGS,WATCHES, BRACELETS (AND OTHER
JEWELRIES), AND ARTIFICIAL NAILS SHOULD
BE REMOVED PRIORTO SURGICAL HAND
ANTISEPSIS.
 KEEP FINGERNAILS SHORT. DEBRIS FROM
UNDER FINGERNAILS SHOULD BE REMOVED
USINGA NAIL CLEANER/NAIL PICK.
 DARK NAIL POLISH OBSCURESTHE
SUBUNGAL SPACEANDTHE LIKELIHOOD OF
CAREFUL CLEANSING IS REDUCED.

 Agents used for surgical hand antisepsis
should have the following characteristics
 Able to significantly reduce microorganisms on
intact skin
 Have broad‐spectrum activity
 Fast‐acting
 Persistent
 Safe
 Non‐irritating

 Preoperative surgical hand antiseptic agents
 Alcohol
▪ Ethanol
▪ Isopropanol
▪ N-Propanol
 Iodophors
▪ Povidone-iodine
 Biguanides
▪ Chlorhexidine gluconate

 THE ANTIBACTERIAL EFFICACY OF
PRODUCTS CONTAINING HIGH
CONCENTRATIONSOF ALCOHOL BY FAR
SURPASSESTHAT OF ANY MEDICATED
SOAP PRESENTLY AVAILABLE.

 MOST OFTHESE STUDIES EVALUATING
SURGICAL SCRUB ANTISEPTICS HAVE
FOCUSED ON MEASURING HAND
BACTERIAL COLONY COUNTS RATHER
THAN INCIDENCE SSI
 ONLY 1 RCT MEASURED SSI RATES, AND IT
SHOWED SIMILAR RATES BETWEEN AN
ALCOHOL HANDRUBVERSUS A
MEDICATED SOAP HANDSCRUB

 POVIDONE-IODINEAND CHLORHEXIDINE
RESULT IN SIGNIFICANT REDUCTION IN
BACTERIAL COUNTS
 CHLORHEXIDINE BASED AQUEOUS
SCRUBS ARE MORE EFFECTIVETHAN
POVIDONE IODINE IN LOWERING NUMBER
OF CFUS ONTHE HANDS

 Traditionally, aqueous antimicrobial soaps
require a surgical scrub with the use of brushes.
 Recently, almost all studies discourage the use
of brushes. It can cause skin abrasions and
changes in microbial flora that can lead to an
increased risk of infection.
 Use brushes when the hands are visibly soiled.

 Administration of an antimicrobial agent or
agents before initiation of certain specific
types of surgical procedures to reduce the
number of microbes that enter the tissue or
body cavity
 Used to reduce the risk of SSI

Mangram AJ et al. Infect Control Hosp Epidemiol. 1999;20:250-278.
Preop administration, serum levels adequate
throughout procedure with a drug active
against expected microorganisms.
High Serum Levels
1. Preop timing
2. IV route
3. Highest dose
of drug
During Procedure
1. Long half-life
2. Long procedure–
redose
3. Large blood loss–
redose
Duration
1. None after wound
closed
2. 24 hours maximum

 USE AN ANTIMICROBIALAGENT BASED ON
ITS EFFICACYAGAINSTTHE MOST
COMMON PATHOGENS CAUSING SSI FOR A
SPECIFIC OPERATION
 GIVENAS A SINGLE DOSE OR CONTINUED
FOR LESSTHAN 24 HOURS

 Time the infusion of the initial dose of
antimicrobial agent so that a bactericidal
concentration of the drug is established in
serum and tissues by the time the skin is
incised.
 The optimal time for administration of
preoperative doses is within 60 minutes
before surgical incision.

 MAINTAINTHERAPEUTIC LEVELS OFTHE
ANTIMICROBIALAGENT IN BOTH SERUM
ANDTISSUESTHROUGHOUTTHE
OPERATION AND UNTIL, AT MOST, A FEW
HOURS AFTERTHE INCISION IS CLOSED IN
THE OPERATING ROOM.
 INTRAOPERATIVE REDOSING IS NEEDED IF
THE DURATION OFTHE PROCEDURE
EXCEEDSTWO HALF-LIVESOFTHE DRUG

 GIVEN FOR CLEAN-CONTAMINATED
WOUNDS.
 USUALLY NOT INDICATED IN CLEAN
WOUNDS.
 CONTAMINATEDAND DIRTYWOUNDS
WILL NEEDTHERAPEUTIC ANTIMICROBIAL
REGIMEN.

INDICATIONS FOR PROPHYLAXIS IN CLEAN
WOUNDS
 WHEN ANY PROSTHETIC
IMPLANT/MATERIAL/ DEVICEWILL BE
INSERTED
 FOR ANY OPERATION INWHICH AN
INCISIONALOR ORGAN/SPACE SSIWOULD
POSE CATASTROPHIC RISK

 EBPG for Antibiotic Prophylaxis in Elective
Surgical Procedures
 Guide to the Management of Common
Surgical Infections

Biliary Surgery Cefazolin
Cefuroxime
Gastroduodenal Cefazolin
Cefuroxime
Colorectal Co-amoxyclav
Cefoxitin
Ampi-sulbactam
Cefazolin + Metronidazole
CSF Shunts Cloxacillin
Oxacillin
Other cranial surgery Cefuroxime
Cefazolin

Cardiac Surgery Cefazolin
Non-cardiacThoracic Surgery Cefazolin
Ortho Surgery Ceftriaxone
TURP Gentamicin
Ofloxacin
Breast surgery Cefazolin
Cefuroxime
Groin Hernia Surgery none

 THE MICROBIAL LEVEL IN OPERATING
ROOM AIR IS DIRECTLY PROPORTIONALTO
THE NUMBER OF PEOPLE MOVINGABOUT
INTHE ROOM.
 MINIMIZE PERSONNELTRAFFIC DURING
OPERATIONS
 KEEPTHE DOORS CLOSED AT ALLTIMES

 OPERATING ROOMS SHOULD BE
MAINTAINEDAT POSITIVE PRESSUREWITH
RESPECTTO CORRIDORS AND ADJACENT
AREAS.
 POSITIVE PRESSURE PREVENTSAIRFLOW
FROM LESS CLEAN AREAS INTO MORE
CLEANAREAS.

 PERFORM ROUTINE CLEANING OFTHESE
SURFACESTO REESTABLISHA CLEAN
ENVIRONMENTAFTER EACH OPERATION.
 THERE ARE NO DATATO SUPPORT
ROUTINE DISINFECTINGOF
ENVIRONMENTAL SURFACES BETWEEN
OPERATIONS INTHE ABSENCE OF
CONTAMINATIONORVISIBLE SOILING.

 Inadequate sterilization of surgical
instruments has resulted in SSI outbreaks.
 Surgical instruments can be sterilized by
steam under pressure, dry heat, ethylene
oxide, or other approved methods

 Surgical attire refers to scrub suits,
caps/hoods, shoe covers, masks, gloves, and
gowns.
 These barriers minimize a patient’s exposure
to the skin, mucous membranes, or hair of
surgical team members, as well as to protect
surgical team members from exposure to
blood and bloodborne pathogens from the
patient.

 RIGOROUS ADHERENCETOTHE
PRINCIPLES OF ASEPSIS BY ALL SCRUBBED
PERSONNEL ISTHE FOUNDATIONOF
SURGICAL SITE INFECTION PREVENTION.

 Better intraoperative and postoperative
temperature control of the patient may
reduce the risk of SSI.
 Patients maintained at higher core
temperature (> 36.5oC) had an SSI rate lower
than those maintained at lower core
temperature.

 Experimental evidence has favored the
concept that increased oxygen delivery has a
favorable influence in the prevention of
infection.
 It is presumed that increased oxygen
availability is a positive host factor, perhaps
via enhanced production of oxidant products
that facilitate phagocytic eradication of
microbes.

 Effective hemostasis
while preserving
adequate blood supply
 Preventing
hypothermia
 Gently handling tissues
 Avoiding inadvertent
entries into a hollow
viscus
 Removing devitalized
tissues
 Using drains and suture
material appropriately
 Eradicating dead space
 Appropriately
managing the
postoperative incision

 Class I and II wounds may be closed primarily.
 Class III and IV wounds are associated with
higher rates of incisional SSIs and these can be
managed by delayed primary closure or healing
by secondary intention.
 SSI risk stratification may lead to identification
of specific subgroups of patients who will benefit
from specific wound management techniques.

 Monofilament sutures appear to have lower
SSI risk compared to braided sutures

 DRAINS PLACEDTHROUGH AN OPERATIVE
INCISION INCREASE INCISIONAL SSI RISK
 SSI RISK ALSO INCREASESWHEN OPEN
DRAINS ARE USED RATHERTHAN CLOSED
SUCTION DRAINS

 A SURGICAL INCISION CLOSED PRIMARILY IS
USUALLY COVEREDWITH A STERILE
DRESSING FOR 24-48 HOURS.
 BYTHISTIME HEMOSTASIS IS ACHIEVEDAND
A FIBRIN SCAB HAS FORMEDTO SEALTHE
WOUND.
 BEYOND 48 HOURS, IT IS UNCLEARWHETHER
AN INCISION MUST BE COVERED BY A
DRESSING ORWHETHER SHOWERING OR
BATHING IS DETRIMENTALTO HEALING.

 WHEN AWOUND IS LEFT FOR DELAYED
PRIMARY CLOSURE OR HEALING BY
SECONDARY INTENTION, IT IS PACKED
WITH STERILE MOIST GAUZE AND
COVEREDWITH A STERILE DRESSING.
 WHEN A DRESSING MUST BE CHANGED,
USE STERILETECHNIQUE

 THE INTENT OF DISCHARGETEACHING IS
TO:
 MAINTAIN INTEGRITY OFTHE HEALING
INCISION
 EDUCATETHE PATIENT ABOUTTHE SIGNS AND
SYMPTOMS OF INFECTION
 ADVISETHE PATIENT ABOUT WHOMTO
CONTACTTO REPORT ANY PROBLEMS.

 Effective therapy for Incisional SSIs consists
solely of incision and drainage without the
addition of antibiotics.
 Antibiotic therapy:
 evidence of significant cellulitis
 concurrent SIRS

 The wound is opened and is allowed to heal
by secondary intention.
 Change of dressing
 Use of topical antibiotics and antiseptics to
further wound healing remains unproven.

Effective therapy for Organ/Space SSI:
 Source control to resect or repair the
diseased organ
 Débridement of necrotic, infected tissue and
debris
 Administration of antimicrobial agents
directed against aerobes and anaerobes

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