Table 2. This table depicts the rate of successful command following by mental arithmetic in healthy volunteers, conscious neurological patients on the ward, minimally or fully conscious patients in the ICU, and comatose/sedated ICU patients.
Successful command following was defined by ≥4 significant pupillary dilations during five mental arithmetic tasks.
| Healthy volunteers | Neurological patients | Neurological patientsa | ICU patients, MCS or CS | ICU patients, coma/sedation | |
|---|---|---|---|---|---|
| N | 20 | 20 | 21 | 2 | 5 |
| 0 significant | 2 | 3 | 1 | 1b | 1 |
| 1 significant | 2 | 1 | 1 | 0 | 2 |
| 2 significant | 0 | 2 | 1 | 1b | 1 |
| 3 significant | 2 | 6 | 10 | 0 | 1 |
| 4 significant | 13 | 5 | 4 | 0 | 0 |
| 5 significant | 1 | 3 | 4 | 1 | 0 |
| Successful | 70% (n = 14∕20) | 40% (n = 8∕20) | 38% (n = 8∕21) | 33% (n = 1∕3) | 0% (n = 0∕5) |
Notes.
- CS
- conscious
- ICU
- intensive care unit
- MCS
- minimally conscious state
- N
- number of subjects
a
All mental arithmetic tasks involved 2 × 2-ciffered calculations (e.g., 3 × 32), except for 1 × 2-ciffered calculations (e.g., 8 × 32) in neurological patients indicated with (*).
b
This unsedated ICU patient in MCS with a pontine hemorrhagic stroke was examined twice at 7 days interval but failed to show command following during mental arithmetic in both sessions.