The
pneumonia
Pneumonia is an Inflammation, inflammatory condition of the lung primarily affecting the small air sacs known as Pulmonary alveolus, alveoli. Symptoms typically include some combination of Cough#Classification, productive or dry cough, ches ...
severity index (PSI) or PORT Score is a clinical prediction rule that
medical practitioners can use to calculate the probability of
morbidity
A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are asso ...
and
mortality among patients with
community acquired pneumonia.
The PSI/PORT score is often used to predict the need for
hospital
A hospital is a healthcare institution providing patient treatment with specialized Medical Science, health science and auxiliary healthcare staff and medical equipment. The best-known type of hospital is the general hospital, which typically ...
ization in people with pneumonia.
This is consistent with the conclusions stated in the original report that published the PSI/PORT score:
"The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes. This prediction rule may help physicians make more rational decisions about hospitalization for patients with pneumonia."
Mortality prediction is similar to that when using
CURB-65.
Development
The rule uses
demographics
Demography () is the statistical study of human populations: their size, composition (e.g., ethnic group, age), and how they change through the interplay of fertility (births), mortality (deaths), and migration.
Demographic analysis examin ...
(whether someone is older, and is male or female), the coexistence of co-morbid illnesses, findings on
physical examination
In a physical examination, medical examination, clinical examination, or medical checkup, a medical practitioner examines a patient for any possible medical signs or symptoms of a Disease, medical condition. It generally consists of a series of ...
and
vital signs
Vital signs (also known as vitals) are a group of the four to six most crucial medical signs that indicate the status of the body's vital (life-sustaining) functions. These measurements are taken to help assess the general physical health of ...
, and essential laboratory findings. This study demonstrated that patients could be stratified into five risk categories, Risk Classes I-V, and that these classes could be used to predict 30-day survival.
Usage
The purpose of the PSI is to classify the severity of a patient's pneumonia to determine the amount of resources to be allocated for care. Most commonly, the PSI scoring system has been used to decide whether patients with pneumonia can be treated as outpatients or as (hospitalized) inpatients.
*A Risk Class I or Risk Class II pneumonia patient can be sent home on
oral
The word oral may refer to:
Relating to the mouth
* Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid
**Oral administration of medicines
** Oral examination (also known as an oral exam or ora ...
antibiotics.
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*A Risk Class III patient, after evaluation of other factors including home environment and follow-up, may either:
:*be sent home with oral antibiotics
Algorithm
The PSI Algorithm is detailed below. An online, automated PSI calculator was once available on the US AHRQ website for Personal Digital Assistants that are no longer sold. In 2018 AHRQ presented a new toolkit on the basis of CURB-65, an older counterpart to the PSI. In the 2019 ATS/IDSA Guidelines for the Diagnosis and Treatment of Adults with Community-acquired
Pneumonia, PSI was recommended over CURB-65 because of lack of evidence supporting the safety and effectiveness of the latter.
Data source for derivation and validation
The rule was derived then validated with data from 38,000 patients from the MedisGroup Cohort Study for 1989, comprising 1 year of data from 257 hospitals across the US who used the MedisGroup patient outcome tracking software built and serviced by Mediqual Systems ( Cardinal Health). One significant caveat to the data source was that patients who were discharged home or transferred from the MedisGroup hospitals could not be followed at the 30-day mark, and were therefore assumed to be "alive" at that time. Further validation was performed with the Pneumonia Patient Outcomes Research Team ORT(1991) cohort study. This categorization method has been replicated by others
Derivation and validation data
Note: % Died refers to 30-day mortality.
References
External links
Pneumonia: New Prediction Model Proves PromisingCommunity-Acquired Pneumonia Mortality Risk for Adults (Pneumonia Patient Outcomes Research Team - PORT) Score CalculatorFigure 1, Halm E, Teirstein A. Management of Community-Acquired Pneumonia. NEJM 2002 347 (25): 2039
{{DEFAULTSORT:Pneumonia Severity Index
Diagnostic intensive care medicine
Pneumonia
Medical signs