With time and experience, experienced clinicians can usually 'get a feel' for whether or not a patient is seriously ill. Of course, just what such doctors are basing their assessments on varies, and so does the accuracy of these assessments. What is often needed is a more objective way of assessing severity, in a manner than even less experienced clinicians can benefit from.
CURB-65 seeks to do this for pneumonia. The word is an acronym for each of the risk factors measured:
- Confusion - this can be assessed by orientation to time, person and place, for instance.
- Urea greater than 7 mmol/l (Americans may be more familiar with a BUN > 19)
- Respiratory rate of 30 or more breaths per minute
- Blood pressure less than 90/60 (in either the systolic or diastolic components)
- 65 years of age or more
Thus there are five parameters in total, and the more of them that are present in a patient, the worse the prognosis. As you can see, the CURB-65 score is amazingly easy to do (only the 'urea' part takes more than 60 seconds to assess) and the good news is that it has shown to be accurate in predicting mortality. Specific figures may be attached, depending on the CURB-65 score: (I've rounded the figures off)
- 0: → 0.7%
- 1: → 3%
- 2: → 13%
- 3: → 17%
- 4: → 42%
- 5: → 57%
... although these figures are obviously heavily dependent on conditions being the same (i.e. first world, in a setting where ICU care is frequently possible, etc.) as those in the study from which they came.