Pneumonia: Risk Stratification Scoring Tools

Pneumonia Severity Index (PSI)

Fine et al., JAMA 1997

• Pneumonia Patient Outcomes Research Team (PORT)
• A large derivation and validation study with >50,000 patients
• Best identifies low-risk/ low-mortality patients
• Tends to miss higher-risk pneumonia in younger patients because score is based on age
• Does not factor in immunosuppression (eg. HIV) and poor social support

Risk factors	Points
Men	Age (years)
Women	Age (years)-10
Nursing home resident	+10
History of neoplasm	+30
History of liver disease	+20
History of heart failure	+10
History of stroke	+10
History of renal failure	+10
Altered mental status	+20
RR ≥ 30 breaths/ min	+20
SBP < 90 mmHg	+20
Temp < 95F (35C) or ≥104F (40C)	+15
HR ≥ 125 bpm	+10
Arterial pH < 7.35	+30
BUN > 30 mg/dL	+20
Na < 130 mmol/L	+20
Glucose ≥250 mg/dL	+10
Hematocrit < 30%	+10
PaO2 < 60 mmHg	+10
Pleural effusion	+10

PSI Class	Total Points	30-Day Mortality	Disposition
I	< 51	0.1%	Outpatient
II	51-70	0.6%	Outpatient
III	71-90	0.9%	Outpatient vs short-stay inpatient
IV	91-130	9.3%	Inpatient
V	> 130	27.0%	Inpatient ICU

CURB-65 Severity Score

Supported by (British Thoracic Society Standards of Care Committee & Aujesky et al, Am J Med, 2005)

• Best identifies high-risk/ high-mortality patients
• Tends to misclassify moderate-risk pneumonia patients (as low-risk)
• Does not account for co-morbidities and hypoxemia

| | Risk Factor | Points | | ------ | ----------------------------------------------- | -----: | | C** | **Confusion | 1 | | U** | Uremia (BUN >19 mg/dL) | 1 | | **R | R*R ≥ 30 breaths/min | 1 | | *B | B*P low (SBP <90 mmHg or DBP <60 mmHg) | 1 | | *65 | Age ≥ 65 years | 1 |

Total Points	30-Day Mortality	Disposition
0	0.6%	Outpatient
1	3.2%	Outpatient
2	13.0%	Outpatient or short-stay inpatient
3	17.0%	Inpatient
4	41.5%	Inpatient, likely ICU
5	57.0%	Inpatient ICU

SMART-COP

Supported by Australian CAP Study (Charles et al., Clin Infect Dis, 2008)

• Tool to predict need for intensive respiratory or vasopressor support (IRVS)

	Risk factor	Points
S	Systolic BP < 90 mmHg	2
M	Multilobar CXR involvement	1
A	Albumin < 3.5 g/dL	1
R	If age ≤ 50 years: RR ≥ 25 breaths/min If age > 50 years: RR ≥ 30 breaths min	1
T	Tachycardia HR ≥ 125 bpm	1
C	Confusion (new onset)	1
O	Oxygen low If age ≤50 years: PaO2 < 70 mmHg, or O2 sat ≤ 93%, or PaO2/FiO2 < 333 If age >50 years: PaO2 < 60 mmHg, or O2 sat ≤ 90%, or PaO2/FiO2 < 250	2
P	Arterial pH < 7.35	2

Total points	Risk of needing IRVS
0-2	Low
3-4	Moderate (1 in 8)
5-6	High (1 in 3)
≥ 7	Very high (2 in 3)

References

• Aujesky D et. al. Prospective comparison of three validated prediction rules for prognosis in community-acquired pneumonia. Am J Med. 2005 Apr;118(4):384-92. [PubMed]
• Fine MJ et. al. A prediction rule to identify low-risk patients with community-acquired pneumonia. N Engl J Med. 1997 Jan 23;336(4):243-50. [PubMed]
• Charles PG et. al. SMART-COP: a tool for predicting the need for intensive respiratory or vasopressor support in community-acquired pneumonia. Clin Infect Dis. 2008 Aug 1;47(3):375-84. [PubMed]
• British Thoracic Society Standards of Care Committee. BTS Guidelines for the Management of Community Acquired Pneumonia in Adults. Thorax. 2001 Dec;56 Suppl 4:IV1-64. [PubMed]