Discussion

The COVID-19 pandemic placed a notable strain on the healthcare system resulting in increased adverse patient outcomes, delay in care, and increased financial burdens for health systems. ^{Reference Lyall and Lone9,Reference Rosenbaum27,Reference Dorsett31–Reference Grimm33,Reference Kaye, Okeagu and Pham37,Reference Anoushiravani, O’Connor and DiCaprio39,Reference Pei, Yamana and Kandula49} This study supplements existing emergency department research regarding increased adverse outcomes during periods of surge and crowding. ^{Reference Lucero, Sokol and Hyun10,Reference Finkelstein, Maguire and Zemek50,51} It demonstrated the association between the COVID-19 pandemic as a MCD and the severity of illness, overall patient length of stay, inpatient complication rates and cost of care on all patients admitted to an ICU during the first 9 months of disaster response in the United States.

First, we noticed that patients admitted to the ICU in 2020 had higher severity of disease. This was seen across all hospital and community types. Higher CMIs could be secondary to increased relative severity weight from COVID-19 associated MS-DRGs. However, this is unlikely as the Center for Medicare and Medicaid Services (CMS) compensated institutions by adjusting the reimbursement rate, not the weight of illness severity. ^{Reference Gershengorn, Garland and Gong53} This finding may be a means to support the preliminary research that patients delayed presentation to hospitals until their illnesses were critical. ^{Reference Kolata18–Reference Rosenbaum27} Such delays in seeking care are likely multifactorial but could have played a role in presenting a more severe state. ^{Reference Lazzerini, Barbi and Apicella22–Reference Rosenbaum27,Reference Blumenthal, Fowler and Abrams32,Reference Grimm33,Reference Ding, Ramakrishna and Long52} Possible contributors to delay in care include mandatory shutdowns, fear of infection, pandemic-related redistribution of resources, and suspension of screening programs. ^{Reference Kolata18–Reference Rosenbaum27,Reference Ding, Ramakrishna and Long52}

Next, the data demonstrated inferior patient outcomes in the 2020 cohort. It was found that both the total and ICU LOS were increased, and there were increased rates of complications. The worsened outcomes could be attributed to multiple factors. First, as elective surgical procedures were delayed early in the pandemic, there was a likely decreased number of post-operative patients. However, though the medical acuity is lower in the post-operative patients (i.e., lower Charlson Comorbidity Index and Acute Physiology and Chronic Health Evaluation (APACHE) scores) the LOS and cost of care have been comparable for both surgical and medical admissions. ^{Reference Gershengorn, Garland and Gong53} Additionally, elective surgeries resumed between 2 and 8 weeks after they were initially delayed as many health systems tried to prevent significant financial loss. ^{54,Reference Meredith, High and Freischlag55} Previously discussed, there was increased acuity as noted by the use of the CMI, which could contribute to the increased adverse outcomes. Furthermore, lack of tangible resources such as personal protective equipment (PPE), ventilators, venous access catheters and patient rooms may have contributed to the difference. ^{54–Reference Abrams and Greenhawt57} Early in the pandemic, there was a severe deficit in PPE for frontline health care workers which resulted in high rates of infection and death. ^{54–Reference Abrams and Greenhawt57} The lack of PPE and fear of consequences associated with unprotected patient care, likely resulted in decreased frequency of examinations, which potentially affected the ability of providers to detect fluctuations in patients’ conditions. ^{Reference Kwizera, Dünser and Nakibuuka58,Reference Dünser, Baelani and Ganbold59} Additionally, in some circumstances, ICU care was being supplied by providers who had received minimal training in critical care medicine which affected their ability to pivot as needed with patient care changes. ^{Reference Riviello, Letchford and Achieng60,Reference Robertson, Lippa and Broekman61} Finally, intangible resources such as time and the provider’s emotional capacity to respond to increased stress may potentially contribute to outcomes. ^{Reference Restauri and Sheridan62,Reference Koinis, Giannou and Drantaki63} Stress in health care providers has been shown to compromise patient care resulting in worsened outcomes. ^{Reference Alghamdi and Begum64}

It was observed that the death rate for patients admitted to the ICU was not significantly changed between 2019 and 2020. Previous patient factors that have been associated with increased mortality are nosocomial infection, advanced age, elevated APACHE scores and a high number of co-morbid conditions. Systemic factors that contribute to an increased number of deaths are low annual patient volume in the ICU, non-tertiary hospital level of care and bed availability. ^{Reference Liang, Li and Dong65–Reference Uppal, Silvestri and Siegler69} A factor that likely contributed to the lack of observed change in death rate was the length of the study period. This was potentially secondary to patient deaths occurring on the hospital general inpatient service or the hospice units, as the critical care beds were in high demand. The death rate has historically been impacted by increased strain on ICUs with patient surges, however this was over 7 weeks rather than 9 months. ^{Reference Uppal, Silvestri and Siegler69} The 9-month duration, and the wide spectrum of hospitals and health systems included are 2 factors that might have normalized the data of death rate data. Waves of patient surges occurred regionally at different times during the first 9 months of the COVID-19 pandemic which may have caused a false negative error in the unchanged mortality rate. ^{Reference Pei, Yamana and Kandula49}

Lastly, the financial burden sustained by hospitals was significantly higher in 2020 compared to 2019. It is worth noting, this increased cost was in the setting of lower overall patient volumes in 2020. Each ICU patient in 2020 cost an additional average of $3624. This was greatest at regional medical centers ($5603) and hospitals in rural communities ($4238). Like the inferior patient outcomes, this increase was likely multifactorial. The increased length of stay and complication rate would increase costs, although additional financial impact sources such as costs associated with supply and demand discrepancies could have contributed to the difference.

Hospitals underwent multiple changes during the COVID-19 pandemic, including establishing testing centers, increasing bed capacity and developing special pathogens isolation units. ^{Reference Uppal, Silvestri and Siegler69} Many hospitals enacted alternative staffing models, such as instructing staff to remain home to abide by social distancing guidelines—this impacted staffing ratios and utilization of critical care resources. Non-emergent surgeries, procedures and imaging were postponed. All these changes impacted hospital revenue yet allowed for the redeployment of resources to the areas of need. ^{Reference Kaye, Okeagu and Pham37,Reference Anoushiravani, O’Connor and DiCaprio39} Finally, the measures taken to safeguard the health of non-COVID-19 patients and hospital staff, such as additional or repetitive testing and increased hygiene policies, likely contributed to increased costs.