Critical test results for emergency department CT examinations performed at Hamilton Health Sciences, by diagnosis
| CT type | Critical test result | No. of results (95% CI); study period | ||
|---|---|---|---|---|
| Before pandemic (95% CI) | During pandemic (95% CI) | p value | ||
| CT examination of the head | Brain infarction | 20 (12–31) | 17 (10–27) | 0.6 |
| Intracranial hemorrhage | 27 (18–39) | 18 (11–28) | 0.2 | |
| Sinusitis, mastoiditis or orbital cellulitis | 22 (14–33) | 4 (1–10) | 0.002 | |
| CT angiogram of the head and neck | Carotid or vertebral occlusion or > 70% stenosis | 8 (3–16) | 7 (3–14) | 0.8 |
| Intracranial arterial thromboembolism | 1 (0–6) | 5 (2–12) | 0.1 | |
| Dural venous sinus thrombus | 2 (0–7) | 0 (0–4) | 1.0 | |
| CT pulmonary angiogram | Pulmonary embolism | 21 (13–32) | 12 (6–21) | 0.1 |
| CT examination of the abdomen and pelvis | Appendicitis | 8* (3–16) | 11† (5–20) | 0.5 |
| Diverticulitis | 24‡ (15–36) | 22§ (14–33) | 0.8 | |
| Bowel obstruction | 8 (3–16) | 13 (7–22) | 0.3 | |
| Ureteric calculi | 2 (0–7) | 11 (5–20) | 0.03 | |
| Acute aortic syndrome | 0 (0–4) | 0 (0–4) | NA | |
Note: CI = confidence interval, CT = computed tomography, NA = not applicable.
↵* Two complicated by pneumoperitoneum and 1 by abscess.
↵† Two complicated by pneumoperitoneum and 1 by pneumoperitoneum with phlegmon.
↵‡ Two complicated by abscess, 2 by phlegmon and 2 by pneumoperitoneum.
↵§ Four complicated by abscess and 1 by pneumoperitoneum.