Transcript SIRS in pregnancy

SIRS in pregnancy:
A prospective audit of 253 women
Peter Richardson (ST6 Anaesthetics)
Liz Stephenson (Midwifery Supervisor)
Rachel Collis (Consultant Anaesthetist)
Background
CMACE
• “early warning signs went unrecognised”
• “failure to distinguish signs of serious illness
from commonplace symptoms of pregnancy”
• “opportunities to save lives were missed” (70%)
(Lewis G et al, CMACE. BJOG, 2011)
CMACE recommendations
• Immediate, aggressive treatment (~ 1st hour)
• National MEOWS charts
• Need for national guideline for identification and
management of sepsis in pregnancy
• In the interim ~ Surviving Sepsis Campaign
Surviving Sepsis Campaign
• Bundles of care [1]

Resuscitation (up to 6 hours)

Ongoing care (up to 24 hours)
• Review ~15000 patients [2]

7% reduction hospital mortality

Sustained improvement in quality of care
• Sepsis Six
(1. Dellinger RP et al. Crit Care Med, 2004 updated 2008)
(2. Levy MM et al. Crit Care Med, 2010)
Sepsis Six
st
(1
hour)
• High-flow oxygen
• Take blood cultures
• Broad-spectrum IV antibiotics
• Give IV fluids (Hartmann's or equivalent)
• Check Hb and Lactate
• Accurately monitor urine output
Pathophysiology
• Complex and incompletely-understood
• Inflammatory cascade in 3 stages

Organisms → cytokine release

Acute phase response (growth factor,
complement, macrophages, platelets)

Systemic activation (humoral cascade, vascular
permeability, end-organ dysfunction)
(Burdette SD et al. eMedicine, 2011)
SIRS criteria
• “clinical response to non-specific insult”
• 2 or more of the following:

Temperature > 38ºC or < 36ºC

Heart rate > 90

Resp rate > 20 (or PaCO2 < 32mmHg)

WBC count > 12 or < 4 (or > 10% bands)
(Bone RC et al. Chest 2002)
When is a patient septic?
(Bone RC et al, ACCP/SCCM consensus. Chest 1992)
Does SIRS predict sepsis?
• Evidence equivocal
• Up to 70% of ward admissions may have SIRS

26% sepsis

18% severe sepsis

7% died

Time interval to developing sepsis decreases
with number of SIRS criteria
(Rangel-Fausto et al. JAMA, 1995)
Does SIRS predict sepsis?
• Length of hospital stay related to number of
SIRS criteria
(Pittet D et al. Int Care Med, 1995)
Does SIRS predict sepsis?
• On admission to A&E, SIRS criteria are a poor
predictor of in-hospital mortality
(Shapiro N et al. Ann Emerg Med, 2006)
Does SIRS predict sepsis?
• In pregnancy (US study of 913 women):

SIRS criteria in 575 (63%)

MEWS score > 5 in 92 (10%)

5 cases proven sepsis with one death

Positive Predictive Values 0.9% and 0.05%

Conclusion: classic SIRS and MEWS criteria
cannot be used for Obstetric patients
(Lappen JR et al. Am J Obstet Gynecol, 2011)
UHW audit
• Aims
–To evaluate role of classic SIRS criteria in
labouring women presenting to tertiary UK centre
–To establish predictive criteria for identification of
SIRS and sepsis in Obstetric population
Methods
• Institutional approval, LREC not required
• All consecutive women delivering in MLU or
CLU over 12 random days July-Aug 2011
• Audit form by primary midwife; senior review
• Further data from PAS
• Casenotes review where required
Results
• 253 women identified
• 28 excluded from further analysis
–25 elective LSCS
–3 data not recorded
• 225 analysed
Baseline information
• Type of care
–Midwife-led
85 (38%)
–Consultant-led
103 (46%)
–Transfer MLU to CLU
32 (14%)
Baseline information
Parity
120
100
80
60
40
20
0
0
1
2
3
>3
Baseline information
Baseline information
• Risk factors for infection
–Induction of labour
62 (28%)
–Syntocinon infusion
44 (20%)
–Labour >12 hrs
30 (13%)
–SROM > 24 hours
24 (11%)
–Epidural analgesia
77 (34%)
SIRS criteria - Temperature
• Mean maximum intrapartum temp:
36.8
– Range 35.8 – 38.6
– Standard deviation 0.50
– Mean + 2SD = 37.8
• Patients with temp > 38
2
SIRS criteria - Temperature
• Mean minimum intrapartum temp:
36.3
– Range 35.2 – 37.6
– Standard deviation 0.37
– Mean – 2SD = 35.6
• Patients with temp < 36
40
SIRS criteria - Tachycardia
• Patients with tachy > 100
52 (23%)
SIRS criteria - Tachypnoea
• Patients with resps > 20
8 (4%)
SIRS criteria – WBC count
• Measured in 146 (65%)
• Mean WBC count
14.8
– Range 4.9 – 30.8
– Standard deviation 4.9
– Mean + 2SD = 24.6
• Patients with WBC count > 12
107
• Patients with WBC count < 4
0
SIRS and sepsis
• Patients with >= 2 SIRS criteria
51 (23%)
SIRS and sepsis
• 33/51 (65%) of those with SIRS received some
form of further sepsis screening
• 62 others screened despite 1 or 0 criteria
–
–
–
–
–
CRP
Blood culture
Urine culture
HVS
Placenta (hist)
41
10
32
38
7
Positive (>6)
Positive
Positive
Positive
Positive
30
2
3
5
1
Sepsis and SIRS
• Of 10 patients with culture-proven infection:
–
–
–
–
–
–
–
–
1/10 elevated temp
2/10 low temp
6/10 tachycardia
2/10 tachypnoea
7/10 “SIRS”
10/10 at least one SIRS criterion
10/10 raised WBC count
6/6 raised CRP
Conversely…
• 1/3 with max temp > 2SD (>37.8ºC) septic
• 1/2 with min temp < 2SD (<35.6ºC) septic
• 6/52 with tachycardia septic
... but 2/8 with tachypnoea
• 7/51 with 2 SIRS criteria septic
... but 3/9 with 3 SIRS criteria
• 10/107 with raised WBC count
• 6/30 with raised CRP
Risk factors revisited
• 5/44 inductions
• 6/62 on syntocinon infusion
• 3/30 prolonged labour
• 1/24 prolonged SROM
• 7/77 epidural
~ overall about 1 in 10 developed sepsis
Conclusions
• In pregnant patients:
–WBC count of no value in predicting sepsis
–CRP of little value in predicting sepsis
–SIRS criteria of little value in predicting sepsis
–Based on current SSC guidelines, ~ 8/10 patients
would be treated unnecessarily
–Cost and health implications
Who needs Sepsis Six?
• Suggested guidelines:
–Screen and treat all cases suspected on clinical
grounds
–Temp > 2SD (~38ºC)
–Temp < 2SD (~35.5ºC)
–Tachypnoea > 20
–3 or more SIRS criteria
–(WBC count < 4)
–No specific role for raised WBC count or CRP
Thank you
Limitations
• Imperfect definition (“sepsis without SIRS”)
• Incomplete data sets
• Cannot accurately calculate PPV, NPV
• No data for WBC count < 4