What effect did the New Zealand COVID-19 lockdown have on computed tomography-head scan utilisation in patients presenting to the emergency department with traumatic head injuries?

Objectives: To explore the unique impact the first COVID-19 national lockdown in New Zealand (NZ) had on the utility of computed tomography (CT)-head scanning in patients presenting to the ED with head injuries.

Methods: Retrospective observational study of CT-head use in head-injured patients presenting to the ED during the 2020 COVID-19 lockdown compared to the corresponding time period in 2019.

Results: During the lockdown period in 2020, the total number of ED presentations reduced by 30.3% (95% confidence interval [CI] 28.8-31.6) from 13 477 to 9403. The total number of head injury presentations also reduced by 32% (95% CI 27-36.7) from 523 to 356. The proportion of head-injured patients remained similar (3.9% [n = 523] in 2019 vs 3.8% [n = 356] in 2020). Of the head injured patients, 185 (51.9%, 95% CI 44.5-59.4) had CT-head scans performed in 2020 compared to 269 (51.4%, 95% CI 45.2-57.5) in 2019; a reduction of 31.2% (95% CI 24.5-37.9). The proportion of patients who had a CT-head scan remained similar (51.4% [95% CI 45.2-57.5] in 2019 vs 51.9% [95% CI 44.5-59.4] in 2020). There were no significant differences in the proportion of CT-head scans with acute traumatic pathology (13.0% [95% CI 8.7-17.3] in 2019 vs 12.4% [95% CI 7.4-17.5] in 2020, P = 0.86).

Conclusions: During the first COVID-19 lockdown in NZ, the total number of patients presenting to the ED decreased by one third. Reassuringly, the proportion of patients who presented with head injuries, had a CT-head scan performed, and had positive CT-head findings remained the same as the previous year.