Renal Replacement Therapy in a World of Constraints: Lessons from the COVID-19 Pandemic

To the Editor:

We read with interest the insightful article by Mekontso Dessap and coworkers titled “Technical Innovation in Critical Care in a World of Constraints: Lessons from the COVID-19 Pandemic” (1).

Critical care services worldwide have had to cope with constrained conditions during the coronavirus disease (COVID-19) pandemic, particularly because of the limited availability of life-sustaining devices. Mekontso Dessap and colleagues (1) dealt only with the obvious major problems of respiratory failure and mechanical ventilation. However, COVID-19 also causes an excess number of other organ failures, particularly acute kidney injury (AKI), requiring renal replacement therapy (RRT).

Among critically ill patients with COVID-19, 56–76% developed AKI (2), and 14–36% of these patients required RRT (2). This led some teams to face RRT shortages, leading to significant challenges in RRT delivery during the first wave (3). Acute peritoneal dialysis, a modality seldom used in high-income countries, regained interest in this context (4), resulting in outcomes that were similar to those among patients who received extracorporeal RRT (5).

Besides recourse to peritoneal dialysis, a more rational use of extracorporeal RRT can help in coping with such constrained situations. Recent evidence demonstrates that RRT initiation can be safely deferred in many patients with AKI, allowing a major reduction in the number who actually need this treatment (6). In addition to a better selection of patients who need RRT initiation, wiser use of available techniques may allow a substantial increase in the number of patients who can be treated on the same day. Indeed, intermittent hemodialysis may allow the daily treatment of three to four patients with only one machine, in contrast to continuous RRT techniques. This is not the place to compare the relative merits of each technique in normal situations, even if current evidence does not provide any definite clue as to the superiority of one over the other technique for any patient-centered outcome (6). Catastrophic conditions, such as those recently encountered, do not allow subtle discussions on the possible minor advantages of any technique.

A frugal approach to critical care should not be limited to mechanical ventilation. The rationalization of RRT delivery is another means of aligning with the principles of sustainability mandated by climate and sanitary crises. This approach may be useful not only in low-income countries but also in rich ones, where economic and environmental challenges should encourage frugality.