APIC Chapter 13 Journal Club

March 18, 2015

Evidence for PracticeInfection Control Measures to prevent

Carbapenem-resistant Acinetobacter baumannii

in a hospital’s ICUs

Presented by: Elsa Santos-Cruz IP CICMount Sinai Hospital

LEVEL I – Experimental Study• Setting:

- The Korean Nosocomial Surveillance System identified Acinetobacter baumannii as the leading cause of

nosocomial infection in the ICUs.- A study was done in the Gyeongsang National University

Hospital located in South Korea. The 890-bed teaching hospital has a 19-bed MICU, a 14-bed SICU, and a 16-bed general isolation ward.

- A retrospective analysis was done to assess effectiveness of different Infection Control measures to prevent infection of Carbapenem-Resistant A. baumannii (CRAB).

Time Period of interventions1- July 2007 to June 2009

All patients with CRAB were placed on Contact Precautions

Disposable gloves and gowns were required upon entry to the room

Alcohol-based hand sanitizer use was encouraged

Daily environmental cleaning of cohorted rooms was done using sodium dichloro-isocyanurate (NaDCC)- containing solution (like bleach)

Nasal screening for CRAB in all ICU patients w/in 24 hrs of admission and weekly thereafter if CRAB was identified in the ICU

2- July 2009 to Dec. 2012 Biweekly education by

Infection Control team of the important of Infection Control protocols

Monitored infection control measures

Promoted infection control practices in preparation for hospital accreditation

Control & Definitions

• Patient with Nosocomial incidence of ESBL+ E. coli and K. pneumoniae (ESBL-EK) were managed with Standard Precautions only.

• Nosocomial was defined as a patient newly infected or colonized with CRAB more than 48 hrs. after admission.

• Patients with multiple positive samples were counted as one episode.

Sample size and composition• During the 6 year study:

Total number of patient admissions = 1,658,999Patients with positive CRAB = 588 (0.35/1000 pt. days)Patients with Nosocomial CRAB = 530 (90% of all CARB pts)

Patients from ICU w/positive CRAB = 342Pts. surveillance culture + for CRAB = 60

Pts. surveillance and clinical culture + = 47Pts. surveillance culture + only = 13

True infection w/ CRAB = 111/530 (21 %)Pneumonia – 76%Bacteremia – 10%Other sites – 14%

Infection Result-based conclusions• Nosocomial Incidence of CRAB/1000 pt. days

2007 = 0.352010 = 0.46 P = 0.0962012 = 0.06 P < .001

• Using segmented regression analysis, there is significant change in the incidence density of CRAB between period 1 and 2.

• Nosocomial Incidence of ESBL-EK2007 = 0.592012 = 1.00 P < .001

• Using segmented regression analysis, there is not significant change for the ESBL-EK

Other Result-based conclusions• Alcohol-based hand rub (AHBR) consumption per

1000 patient days was tracked during the study:5.6L = 2007 5.5L = 20089.6L = 20097.5L = 201011.2L = 201111.9L = 2012 P = <.001

• AHBR consumption was not correlated with change in CRAB (P = .141) although AHBR use increased significantly over the course of the study.

Other Result-based conclusions• Antimicrobial consumption in Defined Daily Doses

(DDD), was also tracked– total antimicrobial use– ß-Lactam/ß-lactamase inhibitor combinations– Extended-spectrum cephalosporins– Quinolones– Carbapenems

• Between 2010 – 2012, antibiotic use decreased– in aggregate (P < .001), – for carbapenems (P = .008) – significantly correlated with a decrease in CRAB (no P value

provided however).

Authors’ conclusions 1• Isolation and Surveillance cultures alone did not

change CRAB incidence (2007-2009)• Between 2010 – 2012, additional education led to

decreased CRAB incidence• Optimal CRAB screening is unknown• Infection Control practices compliance was believed

to be sub-optimal in first time period• Increased compliance with IC practices is inferred by

increased AHBR use in 2nd time period, correlated with preparation for national accreditation visit

• Education about Infection Control is believed to be leading cause of reduced CRAB

Authors’ conclusions 2• Changes in AHBR use did not affect CR-EK rates (those

pts were not tracked or put on isolation precautions)• Cohorting CRAB patients helped reduce rates of CRAB

incidence over the course of the study• Cohorting and isolation helped increase AHBR use and

compliance with Contact Precautions• Decreased use of antimicrobials helped reduce CRAB

rates but not CR-EK rates• Results are similar to a survey in Japan that found that

a reduction of CRAB was associated with Infection Control performance and hospital accreditation

Study Limitations• Inappropriate screening site for CRAB• Multiple changes were made without ability to

evaluate each change’s impact on infection rates• Unable to identify the specific infection control

measure(s) that reduced the incidence density of CRAB

• Compliance with IC measures was not tracked (study was retrospective)

• Unable to evaluate the relationship antimicrobial consumption to the reduction of CRAB

• CRAB isolates were not typed so patient-patient spread cannot be proven

Appraisal Results

• Level II – Experimental Study – Score: B