Discussion
Several studies have shown that the prognosis of COVID-19-related ARDS is unfavorable.1-5 Furthermore, as Rh-negative is quite a rare blood type, ECMO could not be applied to this COVID-19 patient with Rh-negative blood type because it is unreasonable to ensure enough blood products with the same blood type. Thus, we severely restricted the volume of infusion and administered favipiravir and ciclesonide. Despite the presence of acute kidney injury and hypotension, we managed these complications using hydrocortisone and two types of renal replacement therapy. Finally, the patient survived and was discharged from the hospital.
Some clinical guidelines on ARDS recommend conservative fluid management, aiming to achieve a negative balance in body fluid management.14,15 In fact, the benefit of conservative fluid strategy has been supported in the recent randomized controlled trials (RCT).16,17 In the conservative group of these RCTs, the total amount of fluid used in the fluid therapy was 3,000–5,000 mL/day. Meanwhile, in our case, the average total fluids from day 2–7 were 2,942 mL/day. These differences indicate that in order to prioritize minimum lung damage, severe restriction of total fluids was required. We believe that this severe conservative management would enable the successful treatment of respiratory failure without ECMO, although it might partially induce acute kidney injury and refractory hypotension.
As for corticosteroids, there are pros and cons of hydrocortisone administration for critically ill COVID-19 patients.18In fact, the U.S. National Institute of Health guidelines mention that the efficacy of hydrocortisone has not been robustly supported as that of dexamethasone. The reason for this ambiguous statement could be that the two recent RCTs did not demonstrate the efficacy of hydrocortisone, although a significant reduction in the mortality rate was observed with the use of dexamethasone.19-21 However, we believe that hydrocortisone should be positively considered for severe COVID-19 patients who are suffering from refractory hypotension due to secondary adrenal insufficiency like our case. In such cases, the hydrocortisone could provide the following two beneficial effects: suppressing the extreme inflammatory response and raising the blood pressure. Actually, in the latter RCT, the hydrocortisone group which was given dependent on the vasopressor requirements, showed the lowest mortality rate, although with no statistical significance.19 In fact, in our case, although the purpose of hydrocortisone was to improve the hemodynamics without excessive fluid overload, the oxygenation was also restored rapidly in a short while after administration.
Thus, this case highlights the importance of severely conservative fluid management and hydrocortisone therapy for COVID-19 patients, particularly for those with Rh-negative blood type and secondary adrenal insufficiency. These medical interventions need to be positively considered for COVID-19 patients with rare blood types.