Overcrowding in Emergency Departments (EDs) is a phenomenon that is now widespread globally and causes a significant negative impact that goes on to affect the entire hospital. This contributes to a number of consequences that can affect both the number of resources available and the quality of care. Overcrowding is due to a number of factors that in most cases lead to an increase in the number of people within the ED, an increase in mortality and morbidity, and a decrease in the ability to provide critical services in a timely manner to patients suffering from medical emergencies. This phenomenon results in the Emergency Department reaching, and in some cases exceeding, its optimal capacity. In this review, the main causes and consequences involving this phenomenon were collected, including the effect caused by the SARS-CoV-2 virus in recent years. Finally, special attention was paid to the main operational strategies that have been developed over the years, strategies that can be applied both at the ED level (microlevel strategies) and at the hospital level (macrolevel strategies).

Demographic studies show that life expectancy is increasing in developed countries; increased longevity has also increased the share of the older population with often concomitant chronic conditions. An ageing population and increased comorbidities lead to more complex pharmacological therapies (polypharmacy). The particular picture provided by chronic conditions and polypharmacy can lead to longer hospital stays and a greater need for healthcare. Elderly patients are identified as being in the high-risk group for the development of healthcare-associated infections (HAIs) due to the age-related decline of the immune system, known as immunosenescence. Comorbid conditions can often complicate infections, diminishing our ability to treat them effectively. Respiratory tract infections are the most common healthcare-associated infections, followed by urinary tract infections. HAIs in geriatric patients are responsible for longer hospital stays, extended antibiotic therapy, significant mortality, and higher healthcare costs. This is because the microorganisms involved are multidrug-resistant and, therefore, more difficult to eliminate. Moreover, geriatric patients are frequently transferred from one facility (nursing homes, skilled nursing facilities, home care, and other specialty clinics) to another or from one hospital ward to another; these transitions cause care fragmentation, which can undermine the effectiveness of treatment and allow pathogens to be transferred from one setting to another and from one person to another. Multifactorial efforts such as early recognition of infections, restricted use of invasive devices, and effective infection control measures (surveillance, isolation practices, hand hygiene, etc.) can contribute to significant reduction of HAIs in geriatric patients.