Prolonged prothrombin time as an early prognostic indicator of severe acute respiratory distress syndrome in patients with COVID-19 related pneumonia

Abstract

Background: Clinical observations demonstrated that COVID-19 related pneumonia is often accompanied by hematological and coagulation abnormalities including lymphopenia, thrombocytopenia, and prolonged prothrombin time. The evaluation of laboratory findings including coagulation and inflammation parameters may represent a promising approach for early determination of COVID-19 severity.

Methods and materials: In the present study, we aimed to identify laboratory parameters present upon admission in patients with COVID-19 related viral pneumonia and associated with an early in-hospital development of refractory respiratory failure or severe acute respiratory distress syndrome requiring treatment in an intensive care unit. We investigated differences in the C-reactive protein (CRP) and fibrinogen levels, prothrombin time (PT) and international normalized ratio (INR) between COVID-19 patients who had been transferred to an ICU within two weeks after admission (n = 82) and COVID-19 patients with stable course of the disease (n = 74).

Results: Multiple comparisons showed statistically significantly prolonged PT on admission in ICU-transferred COVID-19 patients (14.15 sec, median, CI 95% 13.4 ÷ 14.9) compared to the stable COVID-19 patients (13.25 sec, median, CI 95% 12.9 ÷ 13.6) (p-value = .0005). CRP levels upon admission were statistically significantly higher in ICU-transferred COVID-19 patients (132 mg/L, median, CI95% 113 ÷ 159) compared to the stable COVID-19 patients (51 mg/L, median, CI95% 33 ÷ 72) (p-value < .0001). On-admission fibrinogen and INR levels did not statistically significantly differ between ICU-transferred COVID-19 patients and stable COVID-19 patients.

Conclusion: We suggest that CRP and PT levels present on admission in COVID-19 patients may be used as early prognostic markers of severe pneumonia requiring transfer to ICU.

Keywords: C-reactive protein; COVID-19; SARS-CoV-2; coagulation; coronavirus; pneumonia; prognostic indicator; prothrombin time; respiratory failure.

Figure 1.

Out-of-hospital stay before admission for ICU-transferred COVID-19 patients compared to stable COVID-19 patients, data are presented as median with CI 95%. **p-Value < .01; *p-value < .05.

Figure 2.

Comparisons of lung tissue inflammation severity on admission according to CRP and fibrinogen levels and chest CT (lung tissue affected, %) for ICU-transferred patients vs. control group. ****p-Value < .0001; ns, not significant.

Figure 3.

Multiple comparisons of coagulation parameters (PT and INR) measured upon admission for ICU-transferred COVID-19 patients vs. control group: PTs are significantly different, but INRs are not. ****p-Value < .0001; ns, not significant.

Figure 4.

Multiple comparisons of lung tissue inflammation severity and CRP levels upon admission and on 7th days after hospitalization in ICU-transferred COVID-19 patients and control group. Data presented as median and CI95%. ****p-Value < .0001; ns, not significant.

Figure 5.

Platelet counts upon admission and on the 7th day after hospitalisation in ICU-transferred and stable COVID-19 patients. Data presented as median and CI95%. ****p-Value < .0001; ns, not significant.