A cytokine storm is a hyperinflammatory state secondary to the excessive production of cytokines by a deregulated immune system. It manifests clinically as an influenza-like syndrome, which can be complicated by multi-organ failure and coagulopathy, leading, in the most severe cases, even to death. The term cytokine storm was first used in 1993 to describe the graft-versus-host disease following allogeneic hematopoietic stem cell transplantation. It was then reused to define the adverse syndromes secondary to the administration of immunostimulating agents, such as anti-CD28 antibodies or bioengineered immune cells, i.e., CAR T-cell therapy. Currently, the concept of cytokine storm has been better elucidated and extended to the pathogenesis of many other conditions, such as sepsis, autoinflammatory disease, primary and secondary hemophagocytic lymphohistiocytosis, and multicentric Castleman disease. Moreover, cytokine storm has recently emerged as a key aspect in the novel Coronavirus disease 2019, as affected patients show high levels of several key pro-inflammatory cytokines, such as IL-1, IL-2, IL-6, TNF-α, IFN-γ, IP-10, GM-CSF, MCP-1, and IL-10, some of which also correlate with disease severity. Therefore, since the onset of the pandemic, numerous agents have been tested in the effort to mitigate the cytokine storm in COVID-19 patients, some of which are effective in reducing mortality, especially in critically ill patients, and are now becoming standards of care, such as glucocorticoids or some cytokine inhibitors. However, the challenge is still far from being met, and other therapeutic strategies are being tested in the hope that we can eventually overcome the disease.

It is certain and established that overcrowding represents one of the main problems that has been affecting global health and the functioning of the healthcare system in the last decades, and this is especially true for the emergency department (ED). Since 1980, overcrowding has been identified as one of the main factors limiting correct, timely, and efficient hospital care. The more recent COVID-19 pandemic contributed to the accentuation of this phenomenon, which was already well known and of international interest. Considering what would appear to be a trivial definition of overcrowding, it may seem simple for the reader to hypothesize solutions for what seems to be one of the most avoidable problems affecting the hospital system. However, proposing solutions to overcrowding, as well as their implementation, cannot be separated from a correct and precise definition of the issue, which must consider the main causes and aggravating factors. In light of the need of finding solutions that can put an end to hospital overcrowding, this review aims, through a review of the literature, to summarize the triggering factors, as well as the possible solutions that can be proposed.