The

pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severit ...

severity index (PSI) or PORT Score is a clinical prediction rule that

medical practitioners A health professional, healthcare professional, or healthcare worker (sometimes abbreviated HCW) is a provider of health care treatment and advice based on formal training and experience. The field includes those who work as a nurse, physician (suc ...

can use to calculate the probability of

morbidity A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...

and mortality among patients with

community acquired pneumonia Community-acquired pneumonia (CAP) refers to pneumonia (any of several lung diseases) contracted by a person outside of the healthcare system. In contrast, hospital-acquired pneumonia (HAP) is seen in patients who have recently visited a hospital ...

. The PSI/PORT score is often used to predict the need for

hospital A hospital is a health care institution providing patient treatment with specialized health science and auxiliary healthcare staff and medical equipment. The best-known type of hospital is the general hospital, which typically has an emergen ...

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 CURB-65, also known as the CURB criteria, is a clinical prediction rule that has been validated for predicting mortality in community-acquired pneumonia and infection of any site. The CURB-65 is based on the earlier CURB score and is recommended b ...

Development

The rule uses

demographics Demography () is the statistical study of populations, especially human beings. Demographic analysis examines and measures the dimensions and dynamics of populations; it can cover whole societies or groups defined by criteria such as ed ...

(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, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally consists of a series of questions about the pati ...

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 a ...

, 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 or ...

antibiotics.Page 40
/ref> *A Risk Class III patient, after evaluation of other factors including home environment and follow-up, may either: :*be sent home with oral antibiotics :*be admitted for a short hospital stay with antibiotics and

monitoring Monitoring may refer to: Science and technology Biology and healthcare * Monitoring (medicine), the observation of a disease, condition or one or several medical parameters over time * Baby monitoring * Biomonitoring, of toxic chemical compounds, ...

. *Patients with Risk Class IV-V pneumonia patient should be hospitalized for treatment.

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 and is comparable to the

in predicting mortality.

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