qSOFA Calculator — Quick Sepsis Screening

What qSOFA was built for — and what it became

Sepsis-3 (2016) derived qSOFA as a rapid bedside prompt: in a patient with suspected infection outside the ICU, two of three simple findings — respiratory rate ≥22, systolic pressure ≤100, altered mentation — flag a group with substantially higher mortality, without waiting for labs. It was meant to prompt escalation and a full SOFA assessment, not to define sepsis and not to gate antibiotics. Subsequent validation showed the trade it makes: good specificity, poor sensitivity. By the time qSOFA turns positive, many septic patients are already sick; many others never trip it at all. The 2021 Surviving Sepsis Campaign therefore recommends against using qSOFA as a standalone screen, favoring multivariable approaches (SIRS, NEWS, MEWS) alongside clinical judgment.

The stroke-unit angle

Infection complicates roughly a third of stroke admissions — pneumonia (aspiration above all) and urinary infection lead the list, and post-stroke pneumonia independently predicts mortality. qSOFA misbehaves here in both directions. Falsely positive: baseline aphasia, neglect, or drowsiness from the stroke reads as "altered mentation," and dysautonomia or induced hypertension protocols distort blood pressure criteria. Falsely reassuring: a patient on permissive-hypertension parameters can be developing septic vasodilation while still reading SBP 130. Anchor the mentation item to the documented post-stroke baseline (this is one of many reasons serial GCS/NIHSS documentation pays off), and treat fever plus new tachypnea in a dysphagic patient as pneumonia until proven otherwise, whatever the score says.