Citation: Imperiale TF, Glowinski EA, Lin-Cooper C, et al. Five-year risk of colorectal neoplasia after negative screening colonoscopy. N Engl J Med. 2008;359:1218-1224.
Can validated discharge instability criteria predict mortality or readmission within 30 days of hospital discharge for community acquired pneumonia (CAP)?
Background: Prior prospective cohort data have delineated instability criteria utilizing vital sign criteria at hospital discharge for CAP. However, guidelines for determining patient readiness for discharge remain largely unstudied.
Study design: Prospective, observational cohort study.
Setting: A single, non-urban teaching hospital in Spain.
Synopsis: In this study, 870 adults with CAP were evaluated following discharge. Abnormal oxygenation and vital signs were utilized to calculate an instability score. Criteria for instability were defined as temperature >37.5° C, heart rate <100, respiratory rate >24, systolic blood pressure (SBP) <90 (or diastolic blood pressure, DBP <60), and oxygen saturation <90% (or PaO2 <60).
Of all the instability criteria, only low oxygenation predicted readmission at 30 days (Hazard Ratio [HR] 1.4, p=0.03). However, mortality was significantly increased when instability criteria of temperature (HR 4.5, p=0.04), blood pressure (HR 2.6, p=0.02), respiratory rate (HR 2.4, p=0.03), or oxygenation (HR 2.4, p=0.03) were met. Elevated heart rate was not found to predict death.
The authors assigned each of the significant instability criteria a score of one or two (based on the weight of its hazard ratio), with respiratory rate, low blood pressure, and low oxygenation each assigned one point, and temperature assigned two points. Patients with an instability score of two or more had a six-fold increased risk of death (HR 5.8; 95%, p=0.0001). The negative predictive value (NPV) of an instability score less than two was very helpful (NPV=98%) in identifying patients with low mortality risk; however, the positive predictive value (PPV) of an instability score >2 is not necessarily helpful (PPV=13%) clinically.
Bottom line: Patients with a temperature >37.5° C or any combination of RR >24, SBP <90 (or DBP <60), and SpO2 <90% (or Pa02 <60) are at increased risk of death. Identifying a low instability score is most helpful in clinical practice.
Citation: Capelastegui A, Espana P, Bilbao A, et al. Pneumonia: criteria for patient instability on hospital discharge. Chest. 2008;34:595-600.