Prevention of BSI and VAPMeasuring Change in Outcomes

Part ITed Speroff, PhD

NNIS Surveillance Data

• Central line-associated BSI rate– 5.0/1000 central line-days

• Ventilator-associated pneumonia rate– 5.8/1000 ventilator-days

• The numerator is the number of events– Number of patients with infection or pneumonia

• The denominator is the number of central-line or ventilator days, standardized to 1,000– Census data in the ICU, all patients with lines or on ventilator

• NNIS rate is calculated as number of BSI or VAP events (numerator) divided by observed number of line or vent days for the ICU (denominator) times 1,000

Characteristics ofNNIS Rate Data

• Requires aggregating data over a large sample

• Takes time to accumulate data• Appropriate for Surveillance or Quality

assurance• Appropriate for detecting a rate increase• Not appropriate for detecting a rate

decrease unless sample is huge• Insufficient for Quality Improvement

Statistical Process Control Charts• Used in QI to detect improvement (did it

work?)

• Chart:

Central Line is Mean

UCL

LCL

Upper (UCL) and lower (LCL) control limits are usually 3 sigma units from the mean. A data point above the UCL or below the LCL is a significant change. There are additional control chart rules for detecting change.

X-axis is Time Scale: days, weeks months

BSI Rates and Control Chart

• Excel Tool

• Naming and Saving the File

• Entering Baseline Data

• Setting the Baseline Period for the Control Chart

• Editing Chart and Printing

Name and Save the FileSave Often

Rename the Template File

HCAHospitalName_ICUName_ICUSafety_MonYr

Spreadsheet is now calledMusic City_MICU_ICUSafety_Sep06

Note the Tabs at the Bottom:4 WorksheetsBSI NNIS RateVAP NNIS Rate

BSI NNIS Rate

First Entry: Month/Year10/2004

First Entry: CVC Days

Collecting CVC Days

First Entry: CVC-BSI Infections

Continue Data Entry

Data for Baseline Period Have Been EnteredNote: Data + Chart

Set Baseline Period:Move Cursor to Cell F20

Baseline goes from row 20 to 34Edit $D$50 to $D$34

Move Cursor to Cell G3Edit the Text

Text is a Reminder to You of the Baseline Period:

the data for mean and control limits

Chart: To Edit TitleMove Cursor on Title and Click

Edit to your Hospital Nameand ICU Name

Continue Data Entry:Only Baseline Data determine

Mean and Control Limits

Data Complete through 6/2006What do you see?

End of Part I

Questions and Commentsso far?

Continue to Part II