cliot (version 1.0.0)

psi_port_score: Pneumonia Severity Index (PSI/PORT) Score

Description

Calculates the Pneumonia Severity Index (PSI), also known as the PORT Score, to stratify patients with community-acquired pneumonia (CAP) into risk classes (I-V) based on demographics, comorbidities, physical exam findings, and laboratory results. This helps determine the appropriate site of care (outpatient vs. inpatient).

Usage

psi_port_score(age, sex, nursing_home, neoplastic_disease, liver_disease,
               congestive_heart_failure, cerebrovascular_disease, renal_disease,
               altered_mental_status, respiratory_rate, systolic_bp, temperature_c,
               heart_rate, arterial_ph, bun_mg_dl, sodium_mmol_l, glucose_mg_dl,
               hematocrit_percent, pao2_mmhg, pleural_effusion, sao2_percent = NULL)

Value

A list containing:

PSI_Score

The calculated total score.

Risk_Class

The risk classification (II-V).

Mortality_Risk

Estimated mortality percentage.

Recommendation

Suggested site of care.

Arguments

age

Numeric. Patient age in years.

sex

String. Patient sex ("Male" or "Female").

nursing_home

Numeric (0 or 1). Nursing home resident. (1 = Yes, +10 pts).

neoplastic_disease

Numeric (0 or 1). Active neoplastic disease. (1 = Yes, +30 pts).

liver_disease

Numeric (0 or 1). History of liver disease. (1 = Yes, +20 pts).

congestive_heart_failure

Numeric (0 or 1). History of congestive heart failure. (1 = Yes, +10 pts).

cerebrovascular_disease

Numeric (0 or 1). History of cerebrovascular disease. (1 = Yes, +10 pts).

renal_disease

Numeric (0 or 1). History of renal disease. (1 = Yes, +10 pts).

altered_mental_status

Numeric (0 or 1). Altered mental status (disorientation, stupor, coma). (1 = Yes, +20 pts).

respiratory_rate

Numeric. Respiratory rate in breaths/min. (>= 30: +20 pts).

systolic_bp

Numeric. Systolic blood pressure in mmHg. (< 90: +20 pts).

temperature_c

Numeric. Temperature in Celsius. (< 35 or >= 40: +15 pts).

heart_rate

Numeric. Pulse in beats/min. (>= 125: +10 pts).

arterial_ph

Numeric. Arterial pH. (< 7.35: +30 pts).

bun_mg_dl

Numeric. Blood Urea Nitrogen in mg/dL. (>= 30: +20 pts).

sodium_mmol_l

Numeric. Serum Sodium in mmol/L. (< 130: +20 pts).

glucose_mg_dl

Numeric. Glucose in mg/dL. (>= 250: +10 pts).

hematocrit_percent

Numeric. Hematocrit percentage. (< 30: +10 pts).

pao2_mmhg

Numeric. Arterial partial pressure of oxygen in mmHg. (< 60: +10 pts).

pleural_effusion

Numeric (0 or 1). Presence of pleural effusion on imaging. (1 = Yes, +10 pts).

sao2_percent

Numeric (Optional). Oxygen saturation percentage. Used if PaO2 is not available. (< 90

References

Fine MJ, Auble TE, Yealy DM, et al. A prediction rule to identify low-risk patients with community-acquired pneumonia. N Engl J Med. 1997;336(4):243-250. doi:10.1056/NEJM199701233360402

Examples

# Example 1: Low Risk
# 40yo Male, No comorbidities, Normal Vitals/Labs
# Score = 40
psi_port_score(40, "male", 0, 0, 0, 0, 0, 0, 0, 16, 120, 37, 70, 7.4, 15, 140, 90, 40, 90, 0)

# Example 2: High Risk
# 70yo Female (-10), Nursing Home (+10), CHF (+10), RR 32 (+20), BUN 40 (+20)
# Score = 60 + 10 + 10 + 20 + 20 = 120 (Class IV)
psi_port_score(70, "female", 1, 0, 0, 1, 0, 0, 0, 32, 110, 37, 80, 7.4, 40, 140, 100, 40, 80, 0)