Prevention of Surgical Site Infections William A. Rutala, Ph.D., M.P.H. UNC Health Care System and UNC School of Medicine, Chapel Hill, NC

Prevention of Surgical Site Infections

William A. Rutala, Ph.D., M.P.H.

UNC Health Care System and UNC School of Medicine, Chapel Hill, NC

Disclosure

This educational activity is brought to you, in part, by Advanced Sterilization Products (ASP) and Ethicon. The speaker receives an honorarium from ASP and Ethicon and must present information in compliance with FDA requirements applicable to ASP.

TOPICS

Epidemiology of healthcare associated infections (HAI) Review the morbidity, mortality, and economic

consequences of HAIs Discuss the risk factors and etiology of SSIs Provide strategies to prevent SSIs National initiatives to prevent SSIs

Healthcare-Associated Infections (HAIs)

HAIs are those that develop in the hospital that were neither incubating nor present at the time of admission

40 million persons hospitalized annually in US; 5% or 2M will develop a HAI Morbidity and mortality (90,000 deaths); 6th leading cause

of death in the US Variable prolongation of hospital stay $5-10 billion/year

Impact of Healthcare-Associated Infections

Infection Type Deaths Directly Due To Infection

Deaths, Infections Contributed

% U.S. Total % U.S. Total Pneumonia 3.1 7,087 10.1 22,983 BSI 4.4 4,496 8.6 8,844 SSI 0.6 3,251 1.9 9,726 UTI 0.1 947 0.7 6,503 Total 0.9 19,027 2.7 58,092

Source: Emori TG, Gaynes R. Clin Microbio Rev 1993;6:429

Cost Estimates for Specific Healthcare-Associated Infections

HAI type Weight-Adjusted Cost per HAIMean + SE

Range of Published Estimates of Cost per HAI

VAP 25,072 + 4,132 8,682-31,316BSI 23,242 + 5,184 6,908-37,260SSI 10,443 + 3,249 2,527-29,367CA-UTI 758 + 41 728-810

2005 US dollarsAnderson DJ, et al. ICHE 2007;28:767-773

Most PrevalentMost Prevalent

Urinary Tract33%

S urg ical S ite23%

P rimary B loodstream

19%

O ther25%

Urinary TractS urg ical S iteP rimary B loodstreamO ther

Weinstein RA. Emerg Infect Dis. 1998;4(3):416-420. CDC, NNIS Semiannual Report, Dec 2000.

Surgical Site InfectionSurgical Site Infection


SSIs third most common HAI, accounting for 14-16% of HAIs Among surgical patients, SSIs were most common accounting for

~40% of healthcare-associated infections 67% incisional infections (confined to incision) 33% organ/space infections

Increase an average of 7 days to each hospitalization Increase >$10,000 (2005 $) to each hospitalization Appropriate preoperative administration of antibiotics and other

prevention measures are effective in preventing infection

Surgical Site Infections. Available at: http://www.ihi.org/IHI/Topics/PatientSafety/SurgicalSiteInfections/.Odom-Forren J. Nursing2006. 2006;36(6):58-63.

http://www.ihi.org/IHI/Topics/PatientSafety/SurgicalSiteInfections/


Advances in infection control practices Improved operating room ventilation Sterilization methods Barriers Surgical technique Antimicrobial prophylaxis

Challenges in the Prevention and Management of Surgical Site Infections

Changing population of hospital patients Increased severity of illness Increased numbers of surgical patients who are elderly Increased numbers of chronic, debilitating or immunocompromising

underlying diseases Shorter duration of hospitalization Increased numbers of prosthetic implant and organ transplant operations

performed Public reporting of infection rates/proportions Growing frequency of antimicrobial-resistant pathogens Non-reimbursement for “medical errors”-CMS Lack of compliance with hand hygiene

SSI: Pathogenesis

Risk of surgical site infections =

Dose of bacterial contamination x virulence (toxins)

Resistance of the host

SSI: Primary Risk FactorsSSI: Primary Risk Factors

Endogenous microorganisms Skin-dwelling microorganisms

Most common sourceS aureus most common isolateFecal flora (gnr) when incisions are near the perineum or groin

Exogenous microorganisms Surgical personnel (members of surgical team) OR environment (including air) All tools, instruments, and materials

Mangram AJ, et al. Infect Control Hosp Epidemiol. 1999;20(4):250-278.

SSI: Microbiology (NNIS, 1996)

Pathogen 1986-89 1990-96 Staphylococcus aureus 17% 20% Coagulase-negative staphylococci 12% 14% E. coli 10% 8% Enterococcus sp. 8% 12% Pseudomonas aeruginosa 8% 8% Enterobacter sp. 8% 7% Proteus mirabilis 4% 3% Klebsiella pneumonae 3% 3% Other Streptococcus spp. 3% 3% Candida albicans 2% 3% C. albicans, Grp D strep, Other Gram(+) ---- 2% each

PATHOGENS ASSOCIATED WITH SSIs: NHSN, 2006-2007

0% 5% 10% 15% 20% 25% 30% 35%

Other

A. baumannii

K. oxytoca

Candida

K. pneumoniae

Enterobacter

P. aeruginosa

E. coli

Enterococcus

CoNS

S. aureus

Hidron AI, et al. ICHE 2008;29:996-1011

To Reduce the Risk of Surgical Site InfectionTo Reduce the Risk of Surgical Site Infection

A simple but realistic approach must be applied with the awareness that the risk of SSIs is influenced by

characteristics of the patient, operation, personnel and hospital


CDC: SSI Recommendations, 1999

Definitions IA: Strongly recommended for all hospitals and strongly

supported by experimental or epidemiologic studies IB: Strongly recommended for all hospitals and viewed as

effective by experts II: Suggested for implementation in many hospitals;

suggestive clinical or epidemiologic studies, strong theoretical rationale

SSI: CDC GuidelinesSSI: CDC Guidelines

Patient characteristics

Preoperative issues

Intra-operative issues

Postoperative issues



Patient characteristics/risk factorPreoperative issues




Risk and Prevention in SSIsRisk and Prevention in SSIs

Risk Factor-a variable that has a significant independent association with the development

of SSI after a specific operation

SSI: Intrinsic/Patient Risk Factors

Age-extremes Nutritional status-poor Diabetes-controversial;

increased glucose levels in post-op period ↑ risk

Smoking-nicotine delays wound healing ↑ risk

Obesity>20% ideal body weight

Remote infections ↑ risk Endogenous mucosal

microorganisms Preoperative nares S.

aureus- CT patients Immunosuppressive drugs

may ↑ risk Preoperative stay-surrogate

for severity of illness

Prevention of SSIs

Preoperative preparation of the patient Minimize preoperative stay (II) Identify and treat remote site infections (IA) Adequately control glucose in diabetics (IB) Encourage discontinuation of tobacco for 30d (IB). Consider

delaying elective procedures in severely malnourished patients (II)

No recommendations to taper or discontinue steroids (Unresolved issue)



Preoperative issues




SSI: Preoperative IssuesSSI: Preoperative IssuesModifiable RisksModifiable Risks

Glucose control-in diabetic patientsPreoperative CHG shower

Appropriate hair removal

Hand hygiene

Skin antisepsis

Antimicrobial prophylaxis

Normothermia-hypo higher risks

Mangram AJ, et al. Infect Control Hosp Epidemiol. 1999;20(4):250-278. 5 Million lives. Institute for Healthcare Improvement. Available at: http://ihi.org/IHI/Programs/Campaign/Campaign.htm. Accessed on February 8, 2007.

Prevention of SSIs

Preoperative preparation of the patient Preoperative showers with antiseptic agent at least the night

before (IB) Do not remove hair preoperatively unless it will interfere

with the operation (IA) If hair removed, remove just prior to surgery with electric

clippers (IA) Wash and clean at and around incision site prior to

performing antiseptic skin preparation (IB)

Preoperative Showers

Garibaldi R (J Hosp Infect 1988;11(suppl B):5 Reduction in bacterial counts: Chlorhexidine 9-fold,

povidone-iodine 1.3-fold Cruse and Foord (Arch Surg 1973;107:206)

Clean surgery SSI rate, no shower = 2.3% SSI rate, shower with soap = 2.1% SSI rate, shower with hexachlorophene = 1.3%

Chlorhexidine: Chlorhexidine: Preoperative ShowersPreoperative Showers

CDC recommends preoperative showering with antiseptic1

CHG more effective than PI and triclocarban

Lower rates of intraoperative wound contamination

1. Mangram AJ et al. Infect Control Hosp Epidemiol. 1999;20(4):250-278.2. Garibaldi RA. J Hosp Infect. 1988;11(suppl B):5-9.

Chlorhexidine: Chlorhexidine: Preoperative ShowersPreoperative Showers

Patients who had 2 preoperative showers with CHG 24 hours before surgery had reduced rates of wound infection compared to patients who showered with soap.

Hayek LJ, et al. J Hosp Infect. 1987;10(2):165-172.

0

25

50

75

100

125

150

CH

G C

on

cen

tra

tio

n (

PP

M)

CH

G C

on

cen

tra

tio

n (

PP

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Skin SitesSkin Sites

Left Left ElbowElbow

Right Right ElbowElbow

AbdominalAbdominal Left Left KneeKnee

Right Right KneeKnee

4% Chlorhexidine Gluconate (CHG) Shower - 4% Chlorhexidine Gluconate (CHG) Shower - Mean Skin Surface Concentration (N=60)Mean Skin Surface Concentration (N=60)

MICMIC9090 = 4.8 ppm = 4.8 ppm

Group 2A Group 2A “Morning (AM)”“Morning (AM)”

Group 3A Group 3A

““Both (AM and PM)”Both (AM and PM)”

CHG Shower CHG Shower

Group 1A Group 1A “Evening (PM)”“Evening (PM)”

p p <<0.050.05NSNS

P<0.001P<0.001

Edmiston et al, J Am Coll Surg 2008;207:233-239Edmiston et al, J Am Coll Surg 2008;207:233-239

Preoperative Hair Removal

Seropian and Reynolds (Am J Surg 1971;121:251) SSI rate, razor-shave (microabrasions) = 5.6%

SSI rate, razor-shave >24 hours = 20% SSI rate, razor-shave within 24 hours = 7.1%SSI, razor-shave immediately preop = 3.1%

SSI rate, no removal or depilatory = 0.6%

Preoperative Hair Removal

Cruse and Foord (Arch Surg 1973;107:206) SSI rate, razor-shave = 2.5% Manual hair clipped = 1.7% Electric hair clipper = 1.4% No shave or clip = 0.9%

SSI: Preoperative IssuesSSI: Preoperative IssuesModifiable RisksModifiable Risks

Glucose control-in diabetic patientsPreoperative CHG shower

Appropriate hair removal

Hand hygiene

Skin antisepsis

Antimicrobial prophylaxis

Normothermia-hypo higher risks

Mangram AJ, et al. Infect Control Hosp Epidemiol. 1999;20(4):250-278. 5 Million lives. Institute for Healthcare Improvement. Available at: http://ihi.org/IHI/Programs/Campaign/Campaign.htm. Accessed on February 8, 2007.

Prevention of SSIs

Preoperative preparation of the surgical team Keep nails short and no artificial nails (IB) Perform preoperative surgical scrub for 2-5 minutes with

antiseptic-alcohol, chlorhexidine, iodophors (IB); new waterless, surgical hand antisepsis with alcohol

Perform preoperative scrub including forearms (IB) Do not wear hand/arm jewelry (II) Prohibiting nail polish (No recommendation)

Importance of Our Skin Importance of Our Skin

Microorganisms 80% in first 5 cell layers of epidermis

When skin is perforated Integrity is compromised infection risk

#1 Function:Protective Barrier

Normal Skin Micro-FloraNormal Skin Micro-Flora

Numbers per square centimeter of skin surface (cfu/cm2). Counts on hands range from 3.9x104 to 4.6x106.

Numbers of bacteria that colonize different parts of the body

Surgical Hand Antisepsis


Surgical hand scrubs should: Significantly reduce microorganisms on intact skin Contain a non-irritating antimicrobial preparation Have broad-spectrum activity Be fast-acting and persistent

Active AgentsTincture of

IodineTraditional Iodophors

CHG/ Alcohol

Broad Spectrum X X X

Rapid Activity X X X

Residual Activity X

Activity in Blood/Organic X

Non-Irritating X

Minimal Absorption X

Combined AgentsCombined Agents


Studies suggest that neither a brush nor a sponge is necessary to reduce bacterial counts on the hands of surgical personnel to acceptable levels, especially when alcohol-based products are used

One study (AORN J 2001;73:412) found a brushless application of a preparation of 1% CHG plus 61% ethanol yielded lower bacterial counts on the hands of participants than using a sponge/brush to apply 4% CHG

Prevention of SSI

Preoperative preparation of the patient Use appropriate antiseptic for skin preparation (IB)

Alcohol (70-92%) Chlorhexidine 4%, 2% or 0.5% in alcohol base Iodine/iodophors Apply in concentric circles moving to periphery Prep area to include incision and any drain sites

2% CHG/70% IPA vs. 10% PVP-I2% CHG/70% IPA vs. 10% PVP-I

Randomized, parallel group, open label, healthy human volunteers

55 subjects Microbial samples: right and left abdominal and inguinal sites Efficacy defined as

≥2.0 log10 reduction from baseline CFUs/cm2 on abdominal sites ≥3.0 log10 mean reduction from baseline CFUs/cm2 on inguinal sites

Hibbard JS. J Infus Nursing. 2005;28(3):194-207.

2%2% CHG/70% IPACHG/70% IPA vsvs.. 10% PVP-I 10% PVP-I

0

0.5

1

1.52

2.5

3

3.5

10 minutes 24 hours 48 hoursMean reduct

ion in

CFU

count

s

2% CHG/70% IPA 10 % PVP-1

00.5

11.5

22.5

33.5

44.5

10 minutes 24 hours 48 hoursMea

n re

duct

ion in

CFU

count

s

2% CHG/70% IPA 10% PVP-1

Abdominal Inguinal

P=0.0001 compared to baseline for all results

Hibbard JS. J Infus Nursing. 2005;28(3):194-207

2% CHG/70% IPA for 2% CHG/70% IPA for Foot and Ankle SurgeryFoot and Ankle Surgery

Prospective, randomized trial 125 evaluable patients

40 subjects/group 5 pre-prep baseline

Products ChloraPrep® (2% CHG/70% IPA) DuraPrep® (0.7% Iodine/74% IPA) Techni-Care® (3% Chloroxylenol-PCMX)

Cultures: hallux, web spaces between toes, and control site

Ostrander RV, et al. Bone Joint Surg Am. 2005;87(5):980-985.


Ostrander RV, et al. J Bone Joint Surg Am. 2005;87-A:980-985.

Control = anterior tibia, 12 cm proximal to the ankle joint.


Ostrander RV, et al. J Bone Joint Surg Am. 2005;87-A:980-985.

Prevention of SSIs

Management of infected or colonized surgical personnel Exclude from duty, surgical personnel who have draining

skin lesions until infection eliminated or personnel have received adequate therapy (IB)

Do not routinely exclude personnel colonized with S. aureus or group A strep unless personnel linked epidemiologically to outbreak (IB)

Educate personnel regarding symptoms and signs of infection-have them report to OHS (IB)

Prophylactic Antibiotics

Antibiotics given for the purpose of preventing infection when infection is not present but the risk of postoperative infection is present. Cefazolin is widely used for clean operations.

Surgical Infection PreventionArch Surg 2005;140:174

40.792.947.6All Surgeries (34,133)

79.190.852.4Hysterectomy (2,756)

41.075.940.6Colon (5,279)

36.397.452.0Hip/knee (15,030)

44.891.940.0Vascular (3,207)

34.395.845.3Cardiac (7,861)

Antibiotic stopped within 24 hours

%

Correct Antibiotic

%

Antibiotic within 1 hour%Surgery (N)

Prevent Surgical Site Infections:Institute for Healthcare Improvement

Components if implemented reliably can eliminate SSIs Appropriate use of antibiotics: one hour before incision; appropriate

antibiotics; discontinue with 24 h after surgery (Surgical Care Improvement Project-CMS Quality Indicator)

Appropriate hair removal Maintenance of postoperative glucose control (<200mg/dl) for major

cardiac surgery patients Establishment of postoperative normothermia for colorectal surgery

patients



Preoperative issues




SSI: Primary Risk FactorsSSI: Primary Risk Factors

Endogenous microorganisms Skin-dwelling microorganisms

Most common sourceS aureus most common isolateFecal flora (gnr) when incisions are near the perineum or groin

Exogenous microorganisms Surgical personnel (members of surgical team) OR environment (including air) All tools, instruments, and materials


OR Environment

Air Largest source of airborne microbial contamination is the

OR staff Organisms become airborne as a result of conversation or

shedding from the hair or exposed skin Microbial level directly proportional to the number of people

moving about in the room Improved ventilation associated with decreased SSI

Prevention of SSIs

Intraoperative (Ventilation) Maintain 15 AC/hr (>3 fresh), positive pressure (IB) Filter all air through appropriate filters (IB) Introduce air at ceiling and exhaust near floor (IB) Keep OR doors closed as needed for passage of

equipment, personnel, and patients (IB) Limit the number of OR personnel (IB) Consider ultraclean air for orthopedic implants (II)

OR Environment

Ventilation Three primary design components act to purify the OR air

High-flow ventilation - 15 air changes per hour (3 outside air)

High-efficiency filtration 90-99.97%Positive pressure relative to adjacent areas (prevents

contamination from less clean areas) Maintain the temperature (680-730F [20-230C]) and relative

humidity (30-60%)

Prevention of SSIs

Intraoperative (Cleaning/disinfection environmental surfaces) Clean when visibly soiled/contaminated with EPA approved

disinfectant before the next operation (IB) Do not perform special cleaning after contaminated or dirty

surgery (IB) Do not use tacky mats (IB) Cleaning between surgery if no visible contamination (No

recommendation)

Prevention of SSIs

Intraoperative (Sterilization of surgical instruments) Perform flash sterilization only for patient care items that will

be used immediately. Do not use for reasons of convenience, as an alternative to purchasing additional instrument sets, or to save time (IB)

Sterilize all surgical instruments according to published guidelines (IB)

OR Environment

Microbiologic Sampling No standardized parameters by which to compare

microbial levels obtained from cultures of ambient air or environmental surface

Routine microbiologic sampling cannot be justified Environmental sampling should only be performed as

part of an epidemiologic investigation

Prevention of SSIs

Intraoperative (Surgical attire and drapes-minimize patient’s exposure to skin, mm, or hair of surgical team and protect team from exposure to blood and OPIM) Wear a mask to fully cover the mouth and nose, and a cap

or hood to fully cover hair on head and face (IB) Wear sterile gloves (IB) Do not wear shoe covers to prevent SSIs (IB)

Prevention of SSIs

Intraoperative Use materials for surgical gowns and drapes that are

effective barriers when wet (IB) Change surgical scrubs when visibly soiled, contaminated

and/or penetrated by blood (IB)

Prevention of SSIs

Asepsis and surgical technique Adhere to the principles of asepsis when placing

intravascular devices, spinal or epidural anesthesia catheters, or when dispensing and administering IV drugs (IB)

Handle tissue gently, maintain effective hemostasis, minimize devitalized tissue and foreign bodies, and eradicate dead space at the surgical site (IB)

CDC Surgical Site Infection Prevention Guidelines - 1999

Category IA and IB

No prior infections 15 air changes/hr in ORDo not shave in advance Keep OR doors closed Control glucose in D.M. pts Use sterile instrumentsStop tobacco use Wear a maskShower with antiseptic soap Cover hairPrep skin with approp. agent Wear sterile glovesSurgical team nails short Gentle tissue handlingSurgical team scrub hands DPC for heavily contaminated

Exclude I/C surgical team woundsGive prophylactic antibiotics Closed suction drains (when used)Pos pressure ventilation in OR Sterile dressing x 24-48 hr

SSI surveillance with feedback to surgeons

Conclusions

Surgical site infections result in significant patient morbidity and mortality, and increased hospital cost

Reduction in surgical site infections can be achieved by strict adherence to standard surgical guidelines

Observations have revealed failure to follow standard guidelines

Strict adherence to standard guidelines crucial to reduce SSIs

TOPICS

Epidemiology of healthcare associated infections (HAI) Review the morbidity, mortality, and economic

consequences of HAIs Discuss the risk factors and etiology of SSIs Provide strategies to prevent SSIs National initiatives to prevent SSIs

Thank you

Documents

Prevention of Surgical Site Infections William A. Rutala, Ph.D., M.P.H. UNC Health Care System and UNC School of Medicine, Chapel Hill, NC