NSIH day - 20 Feb 20041

Surveillance of Surgical Site Infections

H.Carsauw, C.SuetensH.Carsauw, C.SuetensNSIHNSIHWIV WIV –– EpidemiologyEpidemiology

NSIH day - 20 Feb 20042

Importance of Surgical Site Infections

l SSI are one of the most common adverse events of surgery

l Excess morbidity, length of stay, costs, antibiotic use…

E Monitoring the incidence of SSI is essential Monitoring the incidence of SSI is essential component in the prevention & control component in the prevention & control

NSIH day - 20 Feb 20043

NSIH – SSI Surveillance

l Reestablished July 2001 before: 1992 – 96

l Protocol in agreement with :

v Quality Decree Flemish government

v Requirements in the field of surveillance of nosocomial infections at European level : HELICSHELICS

NSIH day - 20 Feb 20044

Participation in NSIH - SSI surveillanceJuly 2001 – Dec 2003*

Other Categ.°

Categ. QualityDecree

No. Operations

No. Hosp.Registr. Option

141214.82116.23346

(39+7)1 ICD-9-CM

2 NNIS category

20.37121.78359Total

--55505550133 Aggregated denominator data

* Preliminary data KPRO, Gastric surg, Other vasc, Spinal fusion

°Other categories:

NSIH day - 20 Feb 20045

Number of operations registered by quarter, July 2001 – Dec 2003*

0

1000

2000

3000

4000

5000

6000

7000

8000

2001q3 2001q4 2002q1 2002q2 2002q3 2002q4 2003q1 2003q2 2003q3 2003q4

Quarter

No

. of O

per

atio

ns

ICD-9-CM code NNIS categ. Aggreg. denom. data

NSIH day - 20 Feb 20046

The Quality Decree Flemish government, 01/01/2000

Operation categories to be followed mandatorily:(NNIS system, CDC)

v Colon surgery (COLO)

v Herniorrhaphy (HER)

v Hip prosthesis (HPRO)

v Laminectomy (LAM)

v Vascular surgery (VS)

v Coronary bypass (CBGB & CBGC)

NSIH day - 20 Feb 20047

Stratification by Risk IndexNNIS system, CDC

l Basic Risk Index:

– Wound class– ASA score– Duration

RI : 0 à 3

l Idem + consider Laparo/Endoscopy :

v For COLO , CHOL:Basic Risk Index - 1

v For APPY, GAST:If Basic Risk Index=0:l 0 - lapl 0 – no lap

NOT applicable to other operation categories !

e.g. Hernia, Appendectomy, ...

NSIH day - 20 Feb 20048

Missing Risk Index factors

At least one

Duration

Wound class

ASA score

Risk stratification factor

1,2 %1.1 %1.2 %

9,4 %17.5 %8.6 %

% Missing

TotalOther operation categories

Operation cat. Quality decree

2,7 %0.9 %2.9 %

6,9 %16.2 %6.0 %

NSIH day - 20 Feb 20049

Discharge date versus End of Follow-up in the hospital

01/0

7/01

01/0

1/02

04/0

7/02

04/0

1/03

07/0

7/03

01/0

1/04

Dat

e of

dis

ch./d

eath

, FU

scr

een

01/07/01 01/01/02 04/07/02 04/01/03 07/07/03 01/01/04Date end FU in hosp., pt screen

End FU in hosp > Discharge ??

NSIH day - 20 Feb 200410

Distribution of operations by NNIS Risk Index

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

-1 0 1 2 3 unknown

NNIS Risk Index

No

of o

pera

tions

NSIH day - 20 Feb 200411

SSI rate by NNIS Risk Index

1,5%

2,3%

6,6%

2,4%

0,0%

1,0%

2,0%

3,0%

4,0%

5,0%

6,0%

7,0%

0 1 2+3 unknownNNIS Risk Index

% S

SI

NSIH day - 20 Feb 200412

SSI rate by NNIS operation category

1,1%

6,4%

1,9%

0,8%

1,6% 1,8%

0,0%

1,0%

2,0%

3,0%

4,0%

5,0%

6,0%

7,0%

her colo hpro lam vs cabg

NNIS operation category

% S

SI

NSIH day - 20 Feb 200413

Types of SSI

NSIH day - 20 Feb 200414

Type of SSI by NNIS operation category

0%

20%

40%

60%

80%

100%

HER COLO HPRO LAM VS CBGCNNIS surgical procedure category

% o

f pro

ced

ure

s

Superf. incis.

Deep incis.

Organ/space

NSIH day - 20 Feb 200415

SSI date vs. discharge date

01/0

1/02

02/0

7/02

01/0

1/03

01/0

7/03

Dat

e of

dis

char

ge

01/01/02 02/07/02 01/01/03 01/07/03Infection date

38, 2 %38, 2 %

61, 8 %61, 8 %

NSIH day - 20 Feb 200416

Proportion of SSI diagnosed during hospital stay vs. post-discharge, by surgical procedure category

80,0%

37,5% 46,7% 49,1%27,3%

12,5%

0%

20%

40%

60%

80%

100%

her colo hpro lam vs cabg

NNIS operation category

% o

f SS

I dia

gnos

ed in

hos

p /

post

dis

char

ge

Post discharge

In hospital

NSIH day - 20 Feb 200417

SSI diagnosed after discharge from hospital

l NSIH 1992 - 96: 12,6 %l NSIH 2001 – 03: 38,2 %

Detection source

7%

23%

24%

30%

16%

OPDSurgeon Private

GP

ReadmissionOther

NSIH day - 20 Feb 200418

Discussion & Conclusion

l NSIH - SSI surveillance data : “Flemish data” (Quality decree)

l Missing NNIS Risk Index factors => comparability ?

l Involvement of the surgical profession generally poor (the “owners of the data”)

l Importance of postdischarge surveillance