Objective: To compare patients with COVID-19 in intensive care units (ICUs) to healthy controls using nailfold videocapillaroscopy (NVC), offering standardised findings about micro-circulation.
Study design: A descriptive, cross-sectional study.
Place and duration of study: Medical Intensive Care Unit, Kayseri City Education and Research Hospital, Kayseri, Turkey between January and May 2021.
Methodology: The NVC parameters-capillary morphology, loop diameter, capillary density, dilated capillaries, giant capillaries, avascular areas, microaneurysms, and micro-hemorrhages of 32 patients with COVID-19 and 29 controls were recorded.
Results: The most common capillary morphology in the COVID-19 group (18/32, 56.2%) was serpentine, which also characterised some (6/29, 20.7%) patients in the non-COVID-19 group (p <0.001). The median capillary loop diameter was 77.78 ± 3.63 µm in the COVID-19 group and 71.67 ± 2.19 µm in the non-COVID-19 group (p=0.030). Mean capillary density was 6.41 ± 1.21/1 mm in the COVID-19 group and 8.55 ± 1.12/1 mm in the non-COVID-19 group (p <0.001). The COVID-19 group had significantly more enlarged capillaries (p = 0.001), giant capillaries (p = 0.025), avascular areas (p = 0.028), micro-aneurysms (p <0.001), and micro-hemorrhages (p = 0.011). Mean capillary density was 5.50 ± 0.19/1 mm among deceased patients with COVID-19, but 6.71 ± 0.25/1 mm among survivors (p = 0.011).
Conclusion: NVC findings differed between patients with COVID-19 and controls, and capillary density was less among deceased patients with COVID-19 than survivors.
Key words: Capillaries, COVID-19, İntensive care unit, Micro-circulation, Nailfold videocapillaroscopy.