COVID-19 | Influenza | p-value | |
Demographics and clinical characteristics | |||
Age (years) | 49.5±11.1 | 49.4±11.1 | 0.99 |
BMI (kg·m−2) | 27.6±4.8 | 30.0±6.5 | 0.14 |
Female | 7 (28%) | 7 (28%) | |
Male | 18 (72%) | 18 (72%) | |
Pre-existing diabetes | 4 (16%) | 3 (12%) | 0.68 |
Time on ECMO (days) | 22.7±17.5 | 18.2±18.3 | 0.28 |
Time on mechanical ventilation (days) | 27.4±15.3 | 9.5±3.5 | 0.08 |
APACHE II score | 15.7±5.8 | 16.8±6.7 | 0.57 |
Murray score | 2.9±0.4 | 2.7±0.6 | 0.27 |
PA thrombi | |||
Incidence of PA thrombi | 15 (60%) | 11 (44%) | 0.40 |
Incidence of isolated peripheral PA thrombi | 11 (44%) | 8 (32%) | 0.56 |
CT parameters of pulmonary hypertension | |||
RV/LV diameter ratio | 1.16±0.37 | 0.90±0.13 | 0.008* |
RA/LA diameter ratio | 1.76±1.51 | 1.42±0.30 | 0.45 |
PA/Ao diameter ratio | 1.04±0.16 | 0.71±0.37 | 0.0003# |
PA volume (cm3) | 67.3±14.8 | 59.4±16.6 | 0.08 |
Infarct volume (%) | 0.28±0.93 | 0.19±0.53 | 0.88 |
Data are presented as mean±sd unless otherwise stated. Demographic information and clinical characteristics data were collected retrospectively, using IntelliSpace Critical Care and Anaesthesia software. To collect overall and isolated peripheral pulmonary artery (PA) thrombi data: segmental and subsegmental filling defects retrospectively observed on computed tomography pulmonary angiography (CTPA) were used as an imaging surrogate for peripheral PA thrombi. Data on central PA thrombi and deep vein thrombosis incidence were then collected retrospectively from previous CTPA and lower-limb Doppler ultrasound reports, respectively. CT parameters of pulmonary hypertension were measured retrospectively from CT images of the heart, which were reconstructed into a four-chamber view using Aquarius iNtuition Viewer. Data were analysed using either Student's t-test, Mann–Whitney U-test or Fisher's exact test as appropriate. BMI: body mass index; ECMO: extracorporeal membrane oxygenation; APACHE: Acute Physiology and Chronic Health Evaluation; RV: right ventricle; LV: left ventricle; RA: right atrium; LA: left atrium; Ao: aorta. *: p<0.05; #: p<0.0005.