Surgical site infection 2015

ANTHONY R. PEREZ, MD,MHA,FPCS,FACS,FPSGS,FPALES

Presented during the 21st PHICS Convention, 28-29 May 2015

TO DESCRIBE THE CURRENT EPIDEMIOLOGY OF SURGICAL SITE INFECTIONS ( SSI)

TO DISCUSS INFECTION CONTROL MEASURES THAT SHOULD BE TAKEN TO MINIMIZE THE 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


SSIS ARE THE MOST COMMON NOSOCOMIAL INFECTION, ACCOUNTING FOR 38 PERCENT OF NOSOCOMIAL INFECTIONS.

THE OVERALL RISK OF SSI IS LOW SSI DEVELOP IN 2 TO 5 PERCENT OF THE

MORE THAN 30 MILLION PATIENTS UNDERGOING SURGICAL PROCEDURES EACH YEAR

1 IN 24 PATIENTS WHO UNDERGO INPATIENT SURGERY IN THE UNITED STATES HAS A POSTOPERATIVE SSI


SSI RATES IN AMBULATORY SURGICAL SETTINGS ARE 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 ASSOCIATED WITH SUBSTANTIAL MORBIDITY AND MORTALITY, PROLONGED HOSPITAL STAY, AND INCREASED COST.

AMONG PATIENTS DYING IN THE POST OPERATIVE PERIOD, DEATH RELATED TO SSI IN OVER 75% OF CASES

IN ONE CASE CONTROLLED STUDY USING ORTHOPEDIC PATIENTS, SSI LED TO MEDIAN INCREASE IN HOSPITAL STAY OF 14 DAYS, 2X INCREASE IN RATE OF REHOSPITALIZATION AND INCREASED TOTAL COST > 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







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

Involvesthe deepsoft tissue e.g., fasciaand musclelayers)

Deep soft tissue (fascia & muscle)

Deep

incisional SSI


Subcutaneous tissue

Skin

Superficial

incisional

SSI

Involves anypart of theanatomy, other thanthe incision, which was opened or manipulated during theoperation 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 AFTER THE OPERATIONAND INVOLVES ONLY SKIN OR SUBCUTANEOUS

TISSUEAND AT LEAST ONE OF THE FOLLOWING:

PURULENT DRAINAGE

ORGANISMS ISOLATED

SIGNS OR SYMPTOMS OF INFECTION AND SUPERFICIAL INCISION IS DELIBERATELY OPENED BY SURGEON

DIAGNOSIS OF SUPERFICIAL INCISIONAL SSI BY THE SURGEON



OCCURS WITHIN 30 DAYS AFTER THE OPERATION OR WITHIN 1 YEAR IF IMPLANT IS IN PLACE AND THE INFECTION APPEARS TO BE RELATED TO THE OPERATION

AND INVOLVES DEEP SOFT TISSUES (E.G., FASCIAL AND MUSCLE

LAYERS)AND AT LEAST ONE OF THE FOLLOWING:

PURULENT DRAINAGE FROM THE DEEP INCISION A DEEP INCISION SPONTANEOUSLY DEHISCES OR IS

DELIBERATELY OPENED BY A SURGEON WITH SIGNS AND SYMPTOMS OF INFECTION

AN ABSCESS OR OTHER EVIDENCE OF INFECTION INVOLVING THE 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 AFTER THE OPERATION OR WITHIN 1 YEAR IF IMPLANT IS IN PLACE AND THE INFECTION APPEARS TO BE RELATED TO THE OPERATION

AND INFECTION INVOLVES ANY PART OF THE ANATOMY (E.G.,

ORGANS OR SPACES), OTHER THAN THE INCISION, WHICH WAS OPENED OR MANIPULATED DURING AN OPERATION

AND AT LEAST ONE OF THE FOLLOWING: PURULENT DRAINAGE FROM A DRAIN THAT IS PLACED THROUGH

A STAB WOUND INTO THE ORGAN/SPACE. ORGANISMS ISOLATED AN ABSCESS OR OTHER EVIDENCE OF INFECTION INVOLVING THE

ORGAN/SPACE THAT IS FOUND ON DIRECT EXAMINATION, DURING REOPERATION, OR BY HISTOPATHOLOGIC OR RADIOLOGIC EXAMINATION

DIAGNOSIS OF AN ORGAN/SPACE SSI BY A SURGEON



MICROBIAL CONTAMINATION OF THESURGICAL SITE IS A NECESSARYPRECURSOR OF SSI


QUANTITATIVELY, IT HAS BEEN SHOWN THAT IF A SURGICAL SITE IS CONTAMINATED WITH >105 MICROORGANISMS PER GRAM OF TISSUE, THE RISK OF SSI IS MARKEDLY INCREASED.

THE DOSE OF CONTAMINATING MICROORGANISMS REQUIRED TO PRODUCE INFECTION MAY BE MUCH LOWER WHEN FOREIGN MATERIAL IS PRESENT AT THE 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 woundclassification

ASA score > 2

Length of operation > 75th percentile of the specific operation being performed


ASA Class

Class I A patient in normal health

Class IIA patient with mild systemic disease resulting in no functional limitations

Class IIIA patient with severe systemic disease that limits activity, but is not incapacitating

Class IVA patient with severe systemic disease that is a constant threat to life

Class V A moribund patient not likely to survive without the operation

Class VI 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 INITIATED TO DECREASE MAJOR MORBIDITIES ASSOCIATED WITH NUMEROUS POTENTIAL COMPLICATIONS 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 GLUCONATE ACHIEVED GREATER REDUCTIONS IN SKIN MICROFLORA AND ALSO HAD GREATER RESIDUAL ACTIVITY AFTER A SINGLE APPLICATION

POVIDONE-IODINE EXERT A BACTERIOSTATIC EFFECT AS LONG AS THEY ARE PRESENT ON THE SKIN, BUT MAY BE INACTIVATED BY BLOOD OR SERUM PROTEINS.


NO STUDIES HAVE ADEQUATELY ASSESSED THE COMPARATIVE EFFECTS OF THESE PREOPERATIVE SKIN ANTISEPTICS ON SSI RISK IN WELL-CONTROLLED, OPERATION-SPECIFIC STUDIES


THE OBJECTIVE - TO ELIMINATE THE TRANSIENT MICROORGANISMS AND INHIBIT THE GROWTH OF RESIDENT FLORA UNDER THE GLOVED HAND AT THE BEGINNING OF SURGERY UNTIL THE END OF THE OPERATION.


ABOUT 18% OF GLOVES HAVE TINY PUNCTURES AFTER SURGERY, AND MORE THAN 80% OF CASES GO UNNOTICED BY THE SURGEON.

SURGICAL HAND ANTISEPSIS AIMS TO REDUCE THE RELEASE OF SKIN BACTERIA FROM THE HANDS OF THE SURGICAL TEAM INTO THE OPEN WOUND IN CASE OF AN UNNOTICED PUNCTURE OF THE SURGICAL GLOVE.


RINGS, WATCHES, BRACELETS (AND OTHER JEWELRIES), AND ARTIFICIAL NAILS SHOULD BE REMOVED PRIOR TO SURGICAL HAND ANTISEPSIS.

KEEP FINGERNAILS SHORT. DEBRIS FROM UNDER FINGERNAILS SHOULD BE REMOVED USING A NAIL CLEANER/NAIL PICK.

DARK NAIL POLISH OBSCURES THE SUBUNGAL SPACE AND THE 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 CONCENTRATIONS OF ALCOHOL BY FAR SURPASSES THAT OF ANY MEDICATED SOAP PRESENTLY AVAILABLE.


MOST OF THESE 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 HANDRUB VERSUS A MEDICATED SOAP HANDSCRUB


POVIDONE-IODINE AND CHLORHEXIDINE RESULT IN SIGNIFICANT REDUCTION IN BACTERIAL COUNTS

CHLORHEXIDINE BASED AQUEOUS SCRUBS ARE MORE EFFECTIVE THAN POVIDONE IODINE IN LOWERING NUMBER OF CFUS ON THE 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 ANTIMICROBIAL AGENT BASED ON ITS EFFICACY AGAINST THE MOST COMMON PATHOGENS CAUSING SSI FOR A SPECIFIC OPERATION

GIVEN AS A SINGLE DOSE OR CONTINUED FOR LESS THAN 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.



MAINTAIN THERAPEUTIC LEVELS OF THE ANTIMICROBIAL AGENT IN BOTH SERUM AND TISSUES THROUGHOUT THE OPERATION AND UNTIL, AT MOST, A FEW HOURS AFTER THE INCISION IS CLOSED IN THE OPERATING ROOM.

INTRAOPERATIVE REDOSING IS NEEDED IF THE DURATION OF THE PROCEDURE EXCEEDS TWO HALF-LIVES OF THE DRUG


GIVEN FOR CLEAN-CONTAMINATED WOUNDS.

USUALLY NOT INDICATED IN CLEAN WOUNDS.

CONTAMINATED AND DIRTY WOUNDS WILL NEED THERAPEUTIC ANTIMICROBIAL REGIMEN.



INDICATIONS FOR PROPHYLAXIS IN CLEAN WOUNDS

WHEN ANY PROSTHETIC IMPLANT/MATERIAL/ DEVICE WILL BE INSERTED

FOR ANY OPERATION IN WHICH AN INCISIONAL OR ORGAN/SPACE SSI WOULD POSE CATASTROPHIC RISK


EBPG for Antibiotic Prophylaxis in Elective Surgical Procedures

Guide to the Management of Common Surgical Infections


Biliary Surgery CefazolinCefuroxime

Gastroduodenal CefazolinCefuroxime

Colorectal Co-amoxyclavCefoxitinAmpi-sulbactamCefazolin + Metronidazole

CSF Shunts CloxacillinOxacillin

Other cranial surgery CefuroximeCefazolin


Cardiac Surgery Cefazolin

Non-cardiac Thoracic Surgery Cefazolin

Ortho Surgery Ceftriaxone

TURP GentamicinOfloxacin

Breast surgery CefazolinCefuroxime

Groin Hernia Surgery none




THE MICROBIAL LEVEL IN OPERATING ROOM AIR IS DIRECTLY PROPORTIONAL TO THE NUMBER OF PEOPLE MOVING ABOUT IN THE ROOM.

MINIMIZE PERSONNEL TRAFFIC DURING OPERATIONS

KEEP THE DOORS CLOSED AT ALL TIMES


OPERATING ROOMS SHOULD BE MAINTAINED AT POSITIVE PRESSURE WITH RESPECT TO CORRIDORS AND ADJACENT AREAS.

POSITIVE PRESSURE PREVENTS AIRFLOW FROM LESS CLEAN AREAS INTO MORE CLEAN AREAS.


PERFORM ROUTINE CLEANING OF THESE SURFACES TO REESTABLISH A CLEAN ENVIRONMENT AFTER EACH OPERATION.

THERE ARE NO DATA TO SUPPORT ROUTINE DISINFECTING OF ENVIRONMENTAL SURFACES BETWEEN OPERATIONS IN THE ABSENCE OF CONTAMINATION OR VISIBLE 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 ADHERENCE TO THE PRINCIPLES OF ASEPSIS BY ALL SCRUBBED PERSONNEL IS THE FOUNDATION OF 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 hemostasiswhile 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 PLACED THROUGH AN OPERATIVE INCISION INCREASE INCISIONAL SSI RISK

SSI RISK ALSO INCREASES WHEN OPEN DRAINS ARE USED RATHER THAN CLOSED SUCTION DRAINS



A SURGICAL INCISION CLOSED PRIMARILY IS USUALLY COVERED WITH A STERILE DRESSING FOR 24-48 HOURS.

BY THIS TIME HEMOSTASIS IS ACHIEVED AND A FIBRIN SCAB HAS FORMED TO SEAL THE WOUND.

BEYOND 48 HOURS, IT IS UNCLEAR WHETHER AN INCISION MUST BE COVERED BY A DRESSING OR WHETHER SHOWERING OR BATHING IS DETRIMENTAL TO HEALING.


WHEN A WOUND IS LEFT FOR DELAYED PRIMARY CLOSURE OR HEALING BY SECONDARY INTENTION, IT IS PACKED WITH STERILE MOIST GAUZE AND COVERED WITH A STERILE DRESSING.

WHEN A DRESSING MUST BE CHANGED, USE STERILE TECHNIQUE


THE INTENT OF DISCHARGE TEACHING IS TO:

MAINTAIN INTEGRITY OF THE HEALING INCISION

EDUCATE THE PATIENT ABOUT THE SIGNS AND SYMPTOMS OF INFECTION

ADVISE THE PATIENT ABOUT WHOM TO CONTACT TO 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


Healthcare

Surgical site infection 2015