As well emphasized in the famous catchphrase “time is brain,” rapid diagnosis and quick achievement of reperfusion are crucial for hyperacute stroke management to minimize brain injury. Thus, time indices such as door-to-imaging time (DIT), door-to-needle time (DNT), and door-to-puncture time (DPT) are widely acknowledged as quality indicators of stroke care. For example, the Get With The Guidelines (GWTG)-Stroke program has proposed the following targets to reach: door-to-imaging time within 25 min, door-to-needle time within 60 min, and door-to-puncture time within 2 h (1–3).

Starting from the year 2019, the COVID-19 pandemic has brought worldwide chaos and significantly impacted global lifestyle, including the healthcare system (4). Emergency care system, including that for acute ischemic stroke, is not an exception (5). The pandemic has resulted in delays in the time course of reaching to treatment for acute stroke patients, such as elongated time from symptom detection to hospital arrival in the community, leading to worse functional prognosis (6, 7). After the first COVID-19 case in Korea, the Korean government has implemented quarantine policies, requiring suspected COVID-19 patients to be isolated at home and confirmed cases to be placed in residential treatment centers. In addition, each hospital has implemented its quarantine policies based on circumstances (8, 9).

This study aimed to determine changes in time indices of acute stroke care during the COVID-19 pandemic and effects of in-hospital quarantine policies on these time indices within a single medical center.

Between January 1st, 2019 and February 19th, 2020, a total of 268 individuals who visited the emergency department presented with stroke symptoms within 6 h after a final diagnosis of ischemic stroke. Among these patients, about two-thirds were males. The mean age was 69 years old. Their initial National Institutes of Health Stroke Scale (NIHSS) score upon admission was 5 (IQR: 3–12). A significant proportion of patients had a history of hypertension, accounting for more than half of cases (61%), while over 25% of patients were diagnosed with diabetes mellitus. Notably, 49 (18.3%) patients had a prior medical history of stroke or transient ischemic attack. Among stroke subtypes, large artery atherosclerosis accounted for the highest at approximately one-third, followed by cardioembolism (26.9%) and small vessel occlusion (19.0%). Ninety-five (35%) patients had a large artery occlusion relevant to the infarct lesion. In terms of treatment, about one-third and 20% received intravenous thrombolysis and endovascular thrombectomy, respectively (Table 1).

When looking into the trend between each quarter of the year and quality indicators, we observed a gradual decrease in the number of patients with a concomitant increase in new COVID-19 cases in the community over time (Figure 1A and Supplementary Table S1). Additionally, increasing trends were noted for door-to-neurologist referral time, DIT, and DPT. However, other quality indicators such as DNT and discharge or 3-month mRS exhibited no differences (Figures 1B–F and Supplementary Table S1).

In the multivariable analysis to determine effects of calendar date on quality indicators (Table 2), calendar date seemed to increase DIT and door-to-neurology-referral time in Model 2 after adjusting for age, sex, premorbid mRS, initial NIHSS, and onset-to-arrival time. Furthermore, DPT seemed to be increased after incorporating other covariates (Model 3).

After that, we divided patients into those who arrived in our emergency department before (n = 173) and after (n = 95) the change in in-hospital quarantine policy with mandatory COVID-19 screening. There were no differences in baseline characteristics between these groups except that the premorbid mRS was slightly higher after implementation of the mandatory COVID-19 screening (Supplementary Table S2). However, the proportion of patients treated with endovascular thrombectomy was much higher after the change in in-hospital quarantine policy (15.6% before mandatory COVID-19 screening vs. 28.4% after the mandatory COVID-19 screening). A delay in median DIT was observed comparing before and after the change in quarantine policy (11 min vs. 14 min). Although it did not reach the statistical significance threshold, median door-to-referral time (20 min vs. 23 min) and median DPT (137 min vs. 151.5 min) were also prolonged after the change in the mandatory COVID-19 screening policy. Despite these shifts in quality indicators, no substantial differences were noted in functional outcomes such as discharge mRS scores or 3 months’ mRS scores (Table 3).

After introducing information of whether the patient was admitted before or after implementing the mandatory COVID-19 screening as a variable in addition to previous multivariable models, the change in the quarantine policy seemed to increase the DIT even after adjusting for other covariates (Table 4).

Our results indicate that there are challenges when managing patients who present with acute ischemic stroke during the COVID-19 pandemic. With the advent of the COVID-19 outbreak, there was a progressive decline in the number of patients presenting with acute stroke symptoms. Moreover, during the COVID-19 era, delays of time-to-neurology referral, DIT, and DPT were observed. Remarkably, implementation of the mandatory COVID-19 screening process for all patients during this period contributed to an increase of DIT, indicating its impact on intervention decision-making. While crucial for infection control, this policy notably disrupted timely management for acute stroke patients.

During the pandemic, cases confirmed with COVID-19 in Korea were required to be isolated in negative-pressure rooms within healthcare facilities or living treatment centers based on the severity of their condition (14). Additionally, those COVID-19 patients in Korea tended to avoid seeking healthcare services, although their situations needed such services, potentially having adverse effects on public health (15). This phenomenon was recognized globally. For example, one study has underscored how COVID-19 screening can disrupt optimal care including hospital admissions for cancer patients (16). Regarding stroke patients, a study conducted in China reported a decrease in the number of acute stroke patients visiting the emergency department after the onset of COVID-19, along with an observed increase in both door-to-onset time and door-to-needle time (17). Consistently, a study by Hsiao et al. (18) highlighted a decrease not only in acute stroke consultations but also in reperfusion treatment rates, emphasizing the need for education to ensure that patients in the community can access emergency care. Similarly, a meta-analysis has shown that the onset-to-arrival time of stroke patients is increased during the COVID-19 era because of a tendency to avoid hospital visits (19). Likewise, our study showed that the number of acute stroke patients decreased as the pandemic went on, which could be attributed to reluctance of patients to seek hospital care. The previously mentioned meta-analysis also highlighted that stroke response time was delayed within hospitals due to precautions such as symptom screening and additional isolation policies (19). Strict in-hospital isolation policies can also impact the management of acute ischemic stroke, leading to increased severity and in-hospital mortality rates (5). These not only affects acute stroke patients, but also has repercussions on general stroke patient care, including response times, treatment interventions, and stroke prevention, all of which are deteriorated after the onset of COVID-19 (19–21). These findings emphasize the need for a cautious approach when settling a policy regarding infection control to ensure it does not disrupt the process for acute stroke care.

In response to the advent of the COVID-19 pandemic, the “protected code stroke” was proposed as an approach to managing hyperacute stroke patients during the pandemic. This protocol included a simple screening questionnaire. If COVID-19 was suspected, personal protective equipment should be used when managing patients (22). The Korean Stroke Society has also issued a scientific statement noting that all medical staff should use personal protective equipment, minimize close contact with patients and in-hospital patient transportation, and limit advanced neuroimaging until COVID-19 is ruled out. However, it did not specify that COVID-19 must be excluded before procedures (23). During early stages of the COVID-19 pandemic, real-time RT-PCR assay was considered the gold standard for COVID-19 diagnosis. Although RT-PCR is known for its high sensitivity and specificity, it involves complex procedures and typically takes at least 4 h to get results, potentially causing delays in in-hospital processes (24–26). In response to these concerns, rapid antigen detection tests and rapid molecular assays were introduced. While these tests had somewhat lower sensitivity and specificity than RT-PCR, they were deemed suitable for certain criteria and eventually replaced RT-PCR (27, 28). The implementation of these new diagnostic tools has led to reduced emergency department stays and more efficient management of oncology patients (16, 29). Compared to RT-PCR, they are more cost-effective for acute management of trauma patients (26). Altogether, they have been proven to be valuable for improving management and enabling swift decision-making, although these rapid detection methods show lower sensitivity and specificity than RT-PCR. However, our center introduced RT-PCR as a screening tool, resulting in delays in acute stroke care. Therefore, cautious consideration regarding the necessity of confirmatory tests in emergent situations is essential as other infectious diseases may emerge in the future.

Our study focused on the effect of implementing an in-hospital quarantine policy on quality indicators in addition to worsening of the COVID-19 pandemic itself. Although door-to-neurologist referral time and door-to-puncture time showed delays, these results showed no significant differences after adjusting for potential confounders. Such results might be due to a low statistical power caused by a small sample size. However, implementation of the mandatory COVID-19 screening was found to be associated with a delay in DIT even after adjusting for potential confounders including the calendar date which accounted for worsening of the pandemic itself. In acute stroke patients, shortening the time from symptom onset to reperfusion therapy is the most critical factor affecting their prognosis (1, 30, 31). DIT is a crucial component of door-to-reperfusion time, signifying its central role in acute stroke management and patient outcomes (32). Some previous studies have shown that prolonged DIT can lead to delays in onset-to-treatment time, which in turn may impact a patient’s prognosis, although direct correlations between DIT and patient outcomes were not established in those studies (2, 33, 34). Both the National Institute of Neurological Disorders and Stroke guidelines and the American Heart Association/American Stroke Association recommend maintaining a DIT within 25 min to effectively minimize door-to-reperfusion time (2, 13, 35). This underscores the pivotal nature of door-to-imaging time in optimizing stroke management and improving patient outcomes (2, 13, 35). Several studies demonstrated significant efforts to reduce door-to-needle time and reperfusion time in the care of acute stroke patients, achieving meaningful reductions. However, even these studies consistently reported delays in door-to-image time despite these improvements (36, 37). Divergent from prior research studies that have primarily explored the effect of COVID-19 on acute stroke management, our study distinctly focused on how stringent quarantine policies could influence the quality of care for acute stroke patients. This emphasizes the significance of careful consideration before modifying quarantine policies for situations in which time is a crucial component of efficient management. Given that limited research has dedicated to assessing the impact of quarantine policies, further investigations comparing patient outcomes before and after implementation of such policies are imperative.

Some limitations should be noted for our study. First, the retrospective design itself and the collection of information that relied on medical chart reviews might potentially result in a bias. Second, the small number of study subjects might have resulted in a reduced statistical power of the analysis, mainly for multivariable analysis, which might have underestimated effect sizes or failed to detect significant associations for other quality indicators besides DIT. Third, the study’s single-center nature limits generalizability of our results. Lastly, our analysis did not apply adjustments for multiple hypothesis testing, which could increase the risk of type I error. However, we chose not to adjust for multiple comparisons to avoid inflating type II error, which might obscure clinically meaningful associations. This decision aligns with established literature arguing against routine adjustments in similar contexts (38, 39). Despite this, cautious interpretation of p-values is recommended to ensure the robustness of our conclusions. Although the study has the limitations, it has a notable strength in including 3-month mRS scores for a significant portion of the study population. This allowed for an assessment of longer-term functional outcomes and provided valuable insights into the impact of acute stroke management during the COVID-19 era, enhancing the reliability of our findings.

Our study provides insights into how in-hospital infection control measures can affect the quality of care in hyperacute stroke management. The implementation of stringent quarantine policies impacted DIT and highlighted challenges faced for maintaining efficient stroke care. This emphasizes the need for cautious consideration when adjusting in-hospital quarantine policies for conditions where time-sensitive management is paramount.