This study aims to describe the characteristics of hospitalised COVID-19 patients in a tertiary care hospital close to an international airport in Japan and to compare these characteristics among different waves during the pandemic.

Retrospective observational study.

Tertiary care centre in Japan.

All patients diagnosed with COVID-19 who were hospitalised between January 2020 and April 2022 were included.

Clinical characteristics, characteristics of admission, treatments and outcomes were investigated and compared among six pandemic waves.

A total of 827 patients were included. The median age was 58.0 years. More than half of the patients (58.3%) had at least one comorbidity. The majority of patients (89.0%) were domestically infected patients admitted under the Infectious Diseases Law, while the remaining patients (11.0%) were those diagnosed during airport quarantine and admitted under the Quarantine Act. Hospital-acquired COVID-19 infection occurred in 7.0% of cases, and mainly during the sixth wave. Overall, some form of oxygen therapy, high-flow oxygen devices, invasive mechanical ventilation (IMV) and extracorporeal membrane oxygenation was provided in 46.3%, 10.4%, 4.5% and 1.5% of cases, respectively. Only 1.8% of patients were treated in the intensive care unit (ICU), and 59.5% of patients on IMV were managed in the non-ICU ward. The in-hospital mortality rate was 5.8%. Median age, percentages of some comorbidities, vaccination coverage, medications for COVID-19, types of supportive care and ICU admissions differed significantly among waves.

This study suggests that patient characteristics, vaccination coverage, standard of treatment and severity of illness changed across waves during the COVID-19 pandemic. Intensive care delivery in non-ICU wards was unavoidable due to limited ICU capacity, which may be a key consideration when preparing for future pandemics.

Preoperative biliary drainage (PBD) is often required for patients with pancreatic cancer accompanied by biliary obstruction to ensure the safe administration of neoadjuvant chemotherapy or to manage cholangitis and jaundice. Although endoscopic retrograde cholangiopancreatography (ERCP) is the standard approach for PBD, it carries a significant risk of post-ERCP pancreatitis. Endoscopic ultrasound-guided biliary drainage (EUS-BD), particularly via hepaticogastrostomy (EUS-HGS), offers a promising alternative that avoids papillary manipulation. However, the clinical utility of EUS-BD as primary drainage for PBD remains unclear due to a lack of prospective studies. This multicentre prospective trial aims to evaluate the safety and efficacy of EUS-HGS as primary drainage for PBD in patients with resectable or borderline resectable pancreatic cancer.

This multicentre prospective study involves seven institutions in Japan. Eligible patients will undergo EUS-HGS using a 7Fr plastic stent. The primary endpoint is clinical success, defined by improvements in bilirubin or liver enzyme levels within 14 days postprocedure. Secondary endpoints include technical success rate, adverse event incidence, stent patency and surgical outcomes. A total of 30 patients will be enrolled, considering an expected clinical success rate of 90% and a 10% dropout allowance.

This study has been approved by the National Cancer Center Institutional Review Board (Research No. 2024-084). The results of this study will be reported at an international conference and published in an international peer-reviewed journal.

UMIN ID: 000055173.