Preventing Surgical Site Infections

BC Hip & Knee Arthroplasty CollaborativeFebruary 7, 2006

Felicia Laing, BSc MSc CIC, Infection ControlAnisha Lakhani, BScPharm Pharm DFraser Health Authority

It’s All About Patient Safety

Keys to Safer Hospitals Newsweek Dec 12, 2005“…9000 to 24,000 Canadian patients die annually following an adverse event in hospital. Our report quantified a long-suspected problem in the Canadian healthcare system, and clearly indicates that steps must be taken now to address it. It is time to improve the safety of the care we provide to patients.” – Dr. Peter Norton on the Canadian Adverse Events Study CMAJ 2004; 170(11): 1678-86.

Medical Mishaps

0%

5%

10%

15%

20%

25%

Drug-related

Woundinfect.

Techcomp.

Latecomp.

Diag.mishap

Ther.Mishap

Nontech.comp.

Proc.Related

Leape LL et al NEJM 1991; 324:377-84

Burden of Illness

• Surgical wound $160,900,000• Pneumonia $129,000,000• Bacteremia $36,200,000• Urinary tract $61,500,000• Other sites $65,600,000

Total $453,200,000/year

Emerging AROs (MRSA) Additional $24-35 mill/year

Shirley Paton, Public Health Agency of Canada, May 2005

Burden of Nosocomial Infections

Infection Type

Rate per 100 adm

No. Infections per Year

Extra Days per Case

Extra Bed Days/Yr

Cost per Infection

Cost per Year $000,000

Surgical Wound

1.39 53,421 8.2 438,052 $4,100 $219

Pneumonia 0.60 23,060 20.0 461,200 $10,000 $230

Bacteremia 0.27 10,377 24.0 249,048 $12,000 $125

Urinary 2.39 91,853 2.4 220,447 $1,200 $110

Other 1.07 41,123 4.8 197,390 $2,400 $97

Total 219,834 1,566,137 $781

Surgical Wound InfectionsExtra LOS

Zoutman et al Infect Control Hosp Epidemiol 1998;19:254-259..

Time Period Mean days Median days

Gross Infection LOS 13.6 7.0

Attributable Infection LOS 10.2 4.5

Gross and Attributable Wound Infection Related Length of Stay

Distribution of SSI Costs

Nursing, 51%

Laboratory, 9%

Pharmacy, 10%

Hotel, 14%

Operating Room, 3%

Imaging & Other Tests, 2%Professional

Services, 5%

Outpatient & Emergency, 6%

Zoutman et al Infect Control Hosp Epidemiol 1998;19:254-259.

SSI Risk Factors

• Age• Obesity• Diabetes• Malnutrition• Prolonged preoperative stay• Infection at remote site• Systemic steroid use• Nicotine use

• Hair removal/Shaving• Duration of surgery• Surgical technique• Presence of drains• Inappropriate use of

antimicrobial prophylaxis

Prevention of Surgical Site Infections

• Shorten the length of preoperative stay• Eliminate infections at remote sites• Avoid the removal of hair• Minimize the duration of surgery• Use appropriate antimicrobial prophylaxis

Prevention of Surgical Site Infection

• Preoperative StayIncreased potential for colonization with nosocomial pathogens as pre-op hospital stay increases

• Presence of Remote InfectionsNRC study SSI rate by 2.7 times55% of wound infections with same microorganisms

Prevention of Surgical Site Infections

• Shorten the length of preoperative stay• Eliminate infections at remote sites• Avoid the removal of hair• Minimize the duration of surgery• Use appropriate antimicrobial prophylaxis

Pre-operative Hair Removal

Shaving the surgical site with a razor induces small skin lacerations• Potential sites for infection• Disturbs hair follicles which are often colonized

with S. aureus• Risk greatest when done the night before• Patient education

Be sure that patients know that they should not do you a favour and shave before they come to the hospital!

Pre-operative Shaving/Hair Removal

Alexander, 1983Method of hair removal SSI rate (RR,CI95)Razor 9.3%Clipper 4.6% (0.5,0.07-0.86)

Timing of hair removal SSI rateClipper night before surgery 6.9%Clipper morning of surgery 2.2% (0.3,0.09-1.13)

Arch Surg 1983; 118:347-352

Prevention of Surgical Site Infections

• Shorten the length of preoperative stay• Eliminate infections at remote sites• Avoid the removal of hair• Minimize the duration of surgery• Use appropriate antimicrobial prophylaxis

Length of Operation

• Duration of operation > 2 hours• Increase in the contamination of the wound• Increase in tissue damage from drying,

prolonged retraction and manipulation• Increase in the amount of suture and

electrocoagulation• Greater suppression of host defenses from

blood loss and shock

Cruse and Foord Surg Clin North Am 1980;60:27-40.

To Drain or not to Drain?

• Possible contributor to SSI: mixed reviews• 84-94% use drains, 33-41% remove after 24 hrs

– Chandratreya 1998 JR Coll Edinburgh

• Potential complications– Blood transfusion– Hematoma– Infection

• Bacterial colonization of interior surface – retrograde migration from skin flora

• Foreign body suppress local tissue defense

Downloaded from: Principles and Practice of Infectious Diseases © 2004 Elsevier

Up to 20% of skin-associated bacteria in skin appendages (hair follicles, sebaceous glands) & are not eliminated by topical antisepsis. Transection of these skin structures by surgical incision may carry the patient's resident bacteria deep into the wound and set the stage for subsequent infection.

Skin Antisepsis

Pre-operative Skin PrepChoices, choices, choices

Antiseptic Agent

Gram + bacteria

Gram negbacteria

Speed of killing sensitive bacteria

Inactivated by mucus or proteins

Comments

Alcohols Good Good Fast Moderate Lacks residual effect; alternative for I2 allergies

Chlorhexidine2% and 4% aqueous

Good Good Intermediate Minimal Persistent antimicrobial effect on skin

Iodophors, Iodine in alcohol

Good Good Fast/Intermediate

Moderate to Marked

Good visualization of prep site

Health Canada 1998 http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/98pdf/cdr24s8e.pdf

Pre-operative Skin Prep

• Apply in a manner that preserves skin integrity and prevent injury

• Avoid pooling – Decreases risk of chemical burns – Provides a longer duration of action – Reduces possibility of fire

• Of proven efficacy• Risk stratification• Case finding methods• 1-year follow-up for procedures with implants• Post- discharge surveillance• Reporting rates to surgeons

Cruse and Foord Surg Clin North Am 1980; 60:27-40Olson et al. Arch Surg 1990; 125:794-803.

Surgical Site Infection Surveillance

NNIS Risk Index for SSI Surveillance

Patient-specific Risk Score Total 0-3 points

• Wound class III or IV 1 point

• ASA score 3, 4, 5 1 point

• Duration of surgery >cutpoint 1 point

Risk

0 1 2,3

Knee prosthesis 2 hr 0.88 1.65 2.52

Hip prosthesis 2 hr 0.86 1.28 2.26

Duration Cutpoint

*Infections per 100 proceduresCDC NNIS report December 2004http://www.cdc.gov/ncidod/dhqp/pdf/nnis/2004NNISreport.pdf

SSI Rate* by Surgery Type and Risk Category

Safer Healthcare Now! Campaign

• Promote improvements in patient safety• Six changes that save lives:

Prevent surgical site infectionsPrevent central line-associated bloodstream infectionsPrevent ventilator-associated pneumoniaPrevent adverse drug eventsDeploy rapid response teamsDeliver reliable, evidence-based care for acute myocardial infarction

As of Feb 2006, 146 organizations have joined the campaign

Prevent Surgical Site Infections

• Implement 4 key components of care

Appropriate use of antimicrobial prophylaxisAppropriate hair removalMaintenance of postoperative glucose control for major cardiac surgery patientsPost-operative normothermia for colorectal surgery patients

SSI Surveillance

• Created by the Ministry of Health 2005• Accountable to the Provincial Medical Services

Committee• Maximize coordination and integration of activities

for preventing HAI

• Surveillance initiatives across BC

http://www.picnetbc.ca/

CDADSSI

Bridging the Gap

Preventing Surgical Site Infections Part II

Dr. Anisha Lakhani

February 7, 2006

Prophylaxis against infection

• 1969: Infection risk with THR was 9.5%• 1972: Institution of antimicrobial prophylaxis,

clean air rooms, improved techniques, prosthesis.• Infection rates reduced to 1.3%

(Charnley 1969, 1972)

• Reported rate of infections in revision operations • Hip revision 3.2%• Knee revision 5.6%

(Hanssen 1999)

Infections TKR, a study

• Case control study, Total Knee Replacement– 6,120 patients, 1993-1999, New York & Belgium– 62% osteoarthritis, 20% had rheumatoid arthritis– 116 patients with SSI matched with non infected

patients for gender, age, month of surgery– All pts got IV antibiotics ~ 30 mins prior OR and

were maintained on them for 48 hrs (1995) or 24 hrs (post 1995)

– Choice: Cefazolin or Vancomycin if allergy

Peersman Clin Orthoped Rel Research 2001, 392;

113 patients with infection

• Superficial wound infection (14%)– All within 3 months

• Deep infection (86%)– 29% within 3 months– 71% after 3 months

Risk Factors for Infections

• Prior open surgical procedure• Immunocompromised

– (renal transplant, IVDU, immunosuppressive drugs, infections, open skin.)

• Poor nutrition – Albumin < 35 g/L

• Recurrent UTIs or infection elsewhere• Diabetes Mellitus• Obesity

Note: There was no change in infection rate when antibiotic duration reduced to 24 hr from 48 hrs

Organisms

Which bugs to cover?

• Clean surgical procedures (no entry into GI, gynecologic, and respiratory tracts) Staphylococcus aureus from the exogenous environment or the patient's skin flora is the usual cause of infection

• Cefazolin considered the best choice– Gram positive coverage– Enteric gram negative coverage– Watch for allergies

Cefazolin & Penicillin Allergy

• 80% - 90% of all patients reporting a penicillin allergy are negative for penicillin allergy with skin testing,

• Patients with positive skin test for penicillin allergy are at four fold increased risk for allergic reaction to cephalosporin. Note: This is a very select group of patients.

• A review of almost 16,000 patients treated with cephalosporins – 8.1% of patients with a history of penicillin allergy had

allergic reactions to this class of antibiotics– 1.9% of patients with no reported penicillin allergy history

reacted.• Skin testing for allergy to cephalosporins is much less

standardized than with penicillins and is of questionable clinical benefit

Cefazolin & Pen Allergy

• Detailed & accurate medical history is important

• Patient likely has a true allergy to beta lactams if they report urticaria, pruritis, angioedema, bronchospasm, hypotension or arrhythmia

• Patients with following serious adverse drug reaction should be considered for alternatives to beta lactams: drug induced hypersensitivity syndrome, drug fever or toxic epidermal necrolysis.

Dosing time

Cefazolin

• A single 1 g dose IV provided average serum levels of cefazolin (in mcg/ml) from

• 188.4 at 5 minutes• 135.8 at 15 minutes, • 106.8 at 30 minutes• 73.7 at 1 hour• 16.5 at 4 hours.

• The serum half-life is approximately 1.8 hours following IV administration.

• Excreted unchanged in the urine 60% in the first, up to 80% in 24 hours.

• Bile levels in patients (without obstruction) can reach or exceed serum levels by up to five times.

• In synovial fluid, the cefazolin level becomes comparable to that reached in serum at about 4 hours after drug administration.

Cefazolin dose & time

• Administer 1 g dose within 60 minutes prior to incision

• Use 2 g dose if over 80 Kg weight • Repeat the dose if procedure longer

than 3-4 hours

Right Time – How? Where? When?

• The prophylactic antibiotic process

• Illustrates patient flow• Reveals multiple

opportunities for ensuring the patient receives the right antibiotic and other appropriate interventions.

Ideal process?

• Map out the process

• Find ideal spot• Ensure that

– Right antibiotic is administered

– At the right time

Impact of blood loss & redosing, a Study

• 1,548 patients, Massachusetts (1998- 99)• Cardiac surgery • First dose < 90 mins prior to incision

(cefazolin 1g)• Second dose if procedure lasting > 240

mins and before incision closed

Intra-operative Re-dosing of Cefazolin

Dental Work & Prophylaxis

• Rationale– Risk of bacteremia high in patients with

ongoing inflammation in the mouth. REF– Bacteremia cause seeding via

hematogenous route in patients undergoing total joint implants. REF• Critical period - bacteremia can occur up to 2

year REF• Evidence?

Hanssen Clin Orthop Rel Research 1999; 369

Hanssen Clin Orthop Rel Research 1999; 369

Table 1. Patients at Potential Increased Risk of Hematogenous Total Joint Infection

• All patients during the first two (2) years after prosthetic joint replacement.

• Immunocompromised/immunosuppressed patients – Inflammatory arthropathies (e.g.: rheumatoid arthritis, systemic

lupus erythematosus) – Drug -induced immunosuppression – Radiation-induced immunosuppression

• Patients with co-morbidities (e.g.) – Previous prosthetic joint infections – Malnourishment – Hemophilia – HIV infection – Insulin-dependent (Type 1) diabetes – Malignancy

American Academy of Orthopedic Surgeons

Dental Prophylaxis Limited to High Risk Procedures

Table 2. Incidence Stratification of Bacteremic Dental Procedures*

• HIGHER INCIDENCE1 • Dental extractions • Periodontal procedures including surgery, subgingival placement

of antibiotic fibers/strips, scaling and root planing, probing, recall maintenance

• Dental implant placement and replantation of avulsed teeth • Endodontic (root canal) instrumentation or surgery only beyond

the apex • Initial placement of orthodontic bands but not brackets • Intraligamentary and intraosseous local anesthetic injections • Prophylactic cleaning of teeth or implants where bleeding is

anticipated American Academy of Orthopedic Surgeons

Regimens (Single dose)

Suggested antibiotic prophylaxis regimens

• Patients not allergic to penicillin: cephalexin, cephradine or amoxicillin: 2 grams orally 1 hour prior to dental procedure.

• Patients not allergic to penicillin and unable to take oral medications: cefazolin 1 gram or ampicillin 2 grams IM/IV 1 hour prior to the procedure.

• Patients allergic to penicillin: clindamycin: 600 mg orally 1 hour prior to the dental procedure.

• Patients allergic to penicillin and unable to take oral medications: clindamycin 600 mg IV, 1 hour prior to the procedure.

• *No second doses are recommended for any of these dosing regimens.

American Academy of Orthopedic Surgeons

Key Points On Surgical Prophylaxis OVERVIEW

1. Administer prophylactic antibiotic within 60 minutesprior to the incision.

2. Use Cefazolin 2 g dose if patient weighs > 80 kg. 3. Assess cephalosporin allergy appropriately. 4. Alternative for cephalosporin allergy is Clindamycin

600 mg IV, unless resistant organisms. 5. Repeat the dose in 3 – 4 hours if long procedure.6. Maximum duration of prophylaxis is no more than

24 hours after surgery unless prosthesis. 7. Limit Vancomycin: use in patients with MRSA

colonization, unless allergic to it. Vancomycin must be infused over 1 hour and infusion must begin 1 –2 hours prior to surgery.