Background
Severity criteria | Scoring system/severe sepsis definition |
---|---|
Systemic inflammatory response syndrome (SIRS) [5] | Two or more of (means SIRS): heart rate ≥90 beats/minute, respiratory rate ≥20 breaths/minute, temperature <36 or ≥38°C, white blood cell count <4 or ≥12 cells/mm3
|
Standardised early warning system (SEWS) score [12] | Sum of scores allocated for each clinical observation:* respiratory rate, oxygen saturation, temperature, SBP, heart rate, stimulus required to invoke a response |
CURB65 pneumonia severity score [16] | One point for each of: new confusion, urea >7 mmol/l, respiratory rate ≥30 breaths/min, SBP <90 mmHg or DBP ≤60 mmHg, age ≥65 years |
Institute for Healthcare Improvement website [8] | One or more of (means severe sepsis): SBP <90 mmHg or decreased by >40 mmHg, MAP <70 mmHg, lactate >2 mmol/l, SpO2 ≤90%, urine output <30 ml/hr, creatinine >177 mmol/l, INR >1.5, APTT >60secs, platelets <100/mm3, bilirubin >35 mmol/l |
Surviving Sepsis Campaign guidelines 2008 [7] | One or more of (means severe sepsis): SBP <90 mmHg or decreased by >40 mmHg, MAP <70 mmHg, lactate >4 mmol/l, oliguria, altered mental status |
Survive Sepsis™ website [13] | One or more of (means severe sepsis): SBP <90 mmHg, MAP <65 mmHg, lactate >2 mmol/l, SpO2 ≤90%, urine output <30 ml/hr, creatinine >177 mmol/l, INR >1.5, APTT >60secs, platelets <100/mm3, bilirubin >34 mmol/l |
Methods
Setting and data description
Data analysis
Ethics and approvals
Results
Mortality summary
Variable | Category | N in category+
| 30 day mortality | OR (95% CI) for death within 30 days | 90 day mortality | OR (95% CI) for death within 90 days |
---|---|---|---|---|---|---|
Age group
|
<60 yrs
| 171 | 8% | 1.00 | 13% | 1.00 |
60–69 yrs
| 127 | 9% | 1.06 (0.47–2.43) | 10% | 0.73 (0.36–1.51) | |
70–79 yrs
| 174 | 20% |
2.82 (1.46–5.47)**
| 31% |
2.90 (1.68–4.99)**
| |
≥80 yrs
| 168 | 38% |
6.90 (3.68–12.95)**
| 53% |
7.43 (4.35–12.66)**
| |
Gender
|
Male
| 351 | 18% | 1.00 | 27% | 1.00 |
Female
| 289 | 21% | 1.22 (0.83–1.81) | 30% | 1.16 (0.82–1.64) | |
SIMD quintile
|
1 Deprived
| 130 | 19% | 1.00 | 26% | 1.00 |
2
| 107 | 21% | 1.09 (0.57–2.06) | 30% | 1.21 (0.68–2.13) | |
3
| 115 | 24% | 1.35 (0.74–2.49) | 36% | 1.56 (0.91–2.70) | |
4
| 161 | 18% | 0.92 (0.51–1.67) | 28% | 1.10 (0.65–1.84) | |
5 Affluent
| 111 | 18% | 0.92 (0.48–1.77) | 24% | 0.91 (0.51–1.63) | |
Charlson index
|
0
| 133 | 12% | 1.00 | 16% | 1.00 |
1
| 170 | 15% | 1.33 (0.68–2.60) | 24% | 1.71 (0.95–3.06) | |
2
| 137 | 22% |
2.03 (1.05–3.93)*
| 32% |
2.50 (1.39–4.49)**
| |
≥3
| 200 | 26% |
2.57 (1.40–4.73)**
| 37% |
3.13 (1.81–5.42)**
| |
Admission type
|
Elective
| 129 | 3% | 1.00 | 5% | 1.00 |
Emergency
| 511 | 23% |
9.59 (3.47–26.50)**
| 34% |
10.59 (4.57–24.51)**
| |
Ward type
|
Medicine
| 281 | 30% | 1.00 | 40% | 1.00 |
Surgery
| 244 | 11% |
0.28 (0.17–0.45)**
| 16% |
0.30 (0.20–0.45)**
| |
Orthopaedics
| 68 | 10% |
0.27 (0.12–0.61)**
| 21% |
0.39 (0.21–0.74)**
| |
Other
| 47 | 15% |
0.41 (0.18–0.95)*
| 29% | 0.64 (0.33–1.25) | |
Length of stay prior to sepsis onset
|
1–3 days
| 187 | 11% | 1.00 | 17% | 1.00 |
4–7 days
| 139 | 18% | 1.83 (0.97–3.45) | 27% |
1.83 (1.07–3.13)*
| |
8–21 days
| 213 | 23% |
2.50 (1.42–4.38)**
| 33% |
2.52 (1.56–4.06)**
| |
>21 days
| 101 | 29% |
3.53 (1.88–6.63)**
| 40% |
3.44 (1.98–5.98)**
| |
Blood culture result
|
Negative
| 418 | 18% | 1.00 | 26% | 1.00 |
Contaminant
| 65 | 22% | 1.22 (0.64–2.31) | 32% | 1.39 (0.79–2.44) | |
Positive
| 150 | 21% | 1.20 (0.76–1.91) | 34% |
1.50 (1.00–2.24)*
| |
SIRS criteria
|
2
| 227 | 13% | 1.00 | 22% | 1.00 |
3
| 279 | 19% | 1.60 (0.98–2.62) | 29% |
1.51 (1.01–2.27)*
| |
4
| 132 | 31% |
3.08 (1.80–5.26)*
| 36% |
2.08 (1.29–3.34)**
| |
SEWS score
|
0–1
| 95 | 15% | 1.00 | 26% | 1.00 |
2–3
| 242 | 15% | 1.01 (0.52–1.97) | 19% | 0.66 (0.38–1.15) | |
4–5
| 182 | 21% | 1.53 (0.78–2.99) | 35% | 1.48 (0.86–2.57) | |
≥6
| 121 | 30% |
2.45 (1.23–4.88)**
| 38% | 1.72 (0.96–3.09) | |
CURB65 score
|
0
| 112 | 3% | 1.00 | 6% | 1.00 |
1
| 179 | 11% |
4.57 (1.33–15.76)*
| 17% |
3.14 (1.33–7.41)**
| |
2
| 190 | 23% |
10.95 (3.31–36.19)**
| 34% |
7.80 (3.43–17.74)**
| |
≥3
| 159 | 36% |
20.30 (6.17–66.87)**
| 48% |
14.09 (6.17–32.17)**
| |
IHI criteria
|
Not severe
| 431 | 14% | 1.00 | 23% | 1.00 |
Severe
| 207 | 29% |
2.49 (1.66–3.72)**
| 39% |
2.11 (1.48–3.02)**
| |
SSC criteria
|
Not severe
| 468 | 14% | 1.00 | 22% | 1.00 |
Severe
| 172 | 34% |
3.24 (2.15–4.88)**
| 45% |
2.87 (1.98–4.17)**
| |
Survive Sepsis criteria
|
Not severe
| 450 | 15% | 1.00 | 23% | 1.00 |
Severe
| 188 | 30% |
2.53 (1.69–3.80)**
| 39% |
2.13 (1.48–3.07)**
|
Logistic regression
Severity criteria | Category | 30 day mortality OR (95% CI) | P value | 90 day mortality OR (95% CI) | P value |
---|---|---|---|---|---|
SIRS criteria
|
2
| 1.00 | - | 1.00 | - |
3
| 1.44 (0.83–2.49) | 0.197 | 1.26 (0.78–2.03) | 0.350 | |
4
|
2.36 (1.29-4.33)
|
0.005
| 1.39 (0.80–2.42) | 0.242 | |
SEWS score
|
0–1
| 1.00 | - | 1.00 | - |
2–3
| 1.06 (0.50–2.24) | 0.874 | 0.61 (0.32–1.17) | 0.137 | |
4–5
| 1.36 (0.65–2.87) | 0.413 | 1.36 (0.72–2.60) | 0.346 | |
≥6
|
2.20 (1.02–4.75)
|
0.045
| 1.32 (0.66–2.63) | 0.430 | |
CURB65 score
|
0
| 1.00 | - | 1.00 | - |
1
|
3.90 (1.10–13.81)
|
0.035
|
2.48 (1.02–6.04)
|
0.046
| |
2
|
8.93 (2.60–30.67)
|
0.001
|
5.81 (2.45–13.75)
|
<0.001
| |
≥3
|
16.97 (4.92–58.55)
|
<0.001
|
10.39 (4.33–24.93)
|
<0.001
| |
IHI criteria
|
Not severe
| 1.00 | - | 1.00 | - |
Severe
|
2.64 (1.66–4.21)
|
<0.001
|
2.20 (1.42–3.40)
|
<0.001
| |
SSC criteria
|
Not severe
| 1.00 | - | 1.00 | - |
Severe
|
3.16 (1.98–5.05)
|
<0.001
|
2.68 (1.73–4.15)
|
<0.001
| |
Survive Sepsis criteria
|
Not severe
| 1.00 | - | 1.00 | - |
Severe
|
2.66 (1.65–4.27)
|
<0.001
|
2.12 (1.36–3.30)
|
0.001
|
Performance characteristics of severity criteria
Severity criteria | Performance characteristics for 30 day mortality | AUROC (95% CI) | |||||
---|---|---|---|---|---|---|---|
Mortality below cut-off value | Sensitivity | Specificity | PPV | NPV | 30 day mortality | 90 day mortality | |
SIRS criteria
| 13% | 76% | 38% | 23% | 87% | 0.61 | 0.57 |
(29/227) | (94/123) | (198/515) | (94/411) | (198/227) | (0.55–0.67) | (0.52–0.62)b
| |
SEWS score
| 15% | 60% | 56% | 24% | 85% | 0.60 | 0.59 |
(50/337) | (74/124) | (287/516) | (74/303) | (287/337) | (0.54–0.66) | (0.54–0.65) | |
CURB65 score
| 8% | 81% | 52% | 29% | 92% | 0.72 | 0.72 |
(23/291) | (101/124) | (268/516) | (101/349) | (268/291) | (0.67–0.77) | (0.67–0.76) | |
IHI criteria
| 14% | 50% | 72% | 29% | 86% | 0.61 | 0.59 |
(62/431) | (61/123) | (369/515) | (61/207) | (369/431) | (0.55–0.66) | (0.54–0.64) | |
SSC criteria
| 14% | 48% | 78% | 34% | 86% | 0.63 | 0.61 |
(65/468) | (59/124) | (403/516) | (59/172) | (403/468) | (0.57–0.69) | (0.56–0.66) | |
Survive Sepsis criteria
| 15% | 46% | 75% | 30% | 85% | 0.61 | 0.58 |
(66/450) | (57/123) | (384/515) | (77/188) | (384/450) | (0.55–0.66) | (0.53–0.63) |