POWH Journal Club Article Review

1
POWH Journal ClubArticle Review

• Ben Kwok
• SRMO

2
The Clinical Value of Systemic Inflammatory
Response Syndrome (SIRS) in Abdominal Aortic
Aneurysm Repair

• Norwood M, Bown M, Lloyd G, Bell P, Sayers R.
• Dept of Surg, University of Leicester, Leicester,
  UK
• Eur J Vasc Endovasc Surg 2004 27(3) 292-298

3
Purpose

• To determine whether number of SIRS criteria and
  timing of SIRS correlates with multiple organ
  failure (MOF) and outcome in patients after AAA
  surgery

4
Background

• SIRS 2 or more of these criteria (Bone et al
  Chest 1992)
• WCCgt12 or lt4 or gt10 immature (band) forms
• Temp gt38C or lt36C
• Heart Rate gt 90/min
• Resp Rate gt20/min or PaCO2 lt 4.3kPa (32.25 mmHg)
• SIRS ? sepsis ? septic shock ? multiple organ
  dysfunction

5
Methods

• 151 consecutive AAA repair patients prospectively
  recruited (Oct 00-Apr 02)
• Inclusion criteria- Any AAA repair
• Elective (100)
• Urgent (16) symptomatic repair lt24h post
  admission
• Ruptured (35) intra or retroperitoneal blood at
  laparotomy
• No exclusion criteria
• Daily record post-op of SIRS score
• number of SIRS criteria 0-4

6
Methods

• Outcome measures included
• Organ failure as defined by Knaus et al (Ann Surg
  1985) multiple if gt2 organs failed
• Mortality
• Length of stay in hospital
• Length of stay in surgical ward
• Length of stay in critical care unit

7
Organ Failure
8
Results Elective AAA

• 89 - SIRS at some point during admission
• 54 - SIRS only during first 3 post-op days
• Pts that died (n5) had prolonged and higher mean
  SIRS scores 2.19 c/w 0.95 (plt0.01)
• High early SIRS score ? no correlation with
  adverse outcome
• Cumulative SIRS score gt10 in 1st 4 post-op days
  correlated with higher mortality (p0.02 Fishers
  exact test)

9
Results Elective AAA

• SIRS scores of 3 or 4 during 1st 4 post-op days
  had higher incidence of MOF.
• 1/51 with SIRS score2 developed MOF
• 6/49 with SIRS score3 developed MOF
• BUT No statistically significant difference
  (Fishers exact test p0.06)
• If SIRS during 5th-10th day post-op
• more likely to die (p0.01 Fishers exact test)
• longer ward stay (16.37 days vs 10.94 days)
  p0.02 Students t-test)

10
Results Ruptured AAA

• All 35 patients had SIRS post-op
• Non-survivors had higher mean SIRS score than
  survivors 2.06 vs 1.37 (plt0.01 t-test) BUT no
  difference in survival whether peak SIRS score
  was 2, 3 or 4 (no test or p-value quoted)
• Pts that stayed in hospital longer than the mean
  time had higher mean SIRS score 1.76 vs 1.26
  (p0.04)
• Again, No statistically significant correlation
  between tighter SIRS criteria (3 or 4) and MOF
  (p0.85 ?2)

11
Conclusions of Authors

• No correlation between precise number of SIRS
  criteria and mortality, length of hospital stay
  or organ failure
• In elective AAA repairs
• High cumulative SIRS scores (10) in 1st 4 days
  post-op?more likely to die
• High SIRS score on isolated days not associated
  with increased mortality
• Presence of SIRS from day 5-10?longer hospital
  stay and higher mortality (not influenced by peak
  SIRS score)
• In ruptured AAA repairs
• Early high SIRS scores regardless of outcome

12
Problems

• No statistically significant correlation between
  MOF and tighter SIRS definition (3 or 4 criteria)
• ? Any correlation between SIRS and MOF at all in
  this study not looked at in this study
• ? SIRS ? sepsis ? septic shock ? multiple organ
  dysfunction hypothesis still valid
• More complex analysis of data required to find
  significant results