Physician absenteeism from hospitals, though uncommon, can occur primarily due to strikes held to express professional opinions [12345]. For instance, in the United Kingdom, junior doctors went on strike in 2016 to protest new contract conditions [1]. Similarly, Kenyan physicians went on strike in 2017 over the government’s failure to execute an agreement signed in 2013 [2]. South Korea has also experienced several doctors’ strikes, with the largest and most recent occurring in 2020. This strike was primarily driven by opposition to 4 policies; namely, increasing the number of medical students by 400 each year for the next 10 years, establishing a public medical college for further increase in medical students, including oriental medicine in national health insurance, and approving telemedicine services. The strike, which lasted for 17 days, was led by junior doctors, mainly residents and interns, who left the training hospitals, and by medical students, who refused to attend classes [6].

In 2024, doctors in South Korea, mainly residents and interns, resigned from their training hospitals in disappointment over new medical policies, including the increase of 2,000 medical students. They chose to resign rather than strike due to criticism surrounding doctors’ strikes and recent legal changes made shortly before the new medical policy announcement, including a new law revoking medical licenses after an arrest. These changes led to increased legal remedies and discouraged strikes. Their resignations were driven by frustration over medical policies and were based on individual judgment. More than 90% of the essential residents and interns left their positions, impacting the hospital system in South Korea [7], where they constituted approximately 40% of the total doctors in training hospitals [8].

The absence of residents and interns substantially affected hospital operations. Despite being trainees, they played an essential role in hospital management. Studies based on the 2020 strike in South Korea identified alterations in emergency room systems [69]; however, research on the impact on operations has been limited. Before the massive resignation in 2024, residents and interns were involved in the operations and inpatient clinic management, suggesting that their massive resignation could have an influence on patient outcomes, including intra- and postoperative complications.

This situation presents a valuable research opportunity, as it is difficult to find hospitals in South Korea operating primarily with specialists. Therefore, this study aimed to focus on patient outcomes by comparing surgical complications before and during the junior doctors’ massive resignations.

A total of 218 and 31 patients in the control and crisis periods who underwent gastric cancer surgery, respectively, were included in the study. Approximately 73 surgeries were performed from February 20 to June 10 each year prior to the medical crisis, which decreased to 31 during the medical crisis. No significant difference was observed in terms of patient characteristics between the crisis and control period (Tables 1, 2, 3). The operation duration was 164.5 minutes before the medical crisis and 154.0 minutes during it (P = 0.19) (Table 2).

No significant differences were observed between the 2 periods in terms of the first flatus day after surgery (P = 0.99) or the first liquid diet day after surgery (P = 0.28) (Table 3). The length of hospital stay decreased during the medical crisis (control period, 6.12 days; crisis period, 5.52 days), but this change was not statistically significant (P = 0.57) (Table 3).

The incidence of postoperative complications was 22.02% (48 of 218) during the control period and 9.68% (3 of 31) during the crisis period (P = 0.15) (Table 4). No severe complications (Clavien-Dindo grade ≥IIIa) were observed during the crisis period, and the difference against the control was not statistically significant (P = 0.31) (Table 4).

During the crisis period, 3 patients experienced complications, including paralytic ileus, pleural effusion, and both simultaneously. Changes in the type of complications between the control and crisis periods were not significant (P = 0.94) (Table 4).

Based on the univariate logistic regression analysis, age, sex, BMI, hypertension, diabetes mellitus, type of gastrectomy, operation duration, proximal resection margin, and stage based on the AJCC (American Joint Committee on Cancer) staging system were significantly associated with complication rates. Multivariate logistic regression analysis, including the effect of the medical crisis, revealed that sex (P = 0.03) and BMI (P = 0.03) were significant, while the effect of mass resignation (P = 0.29) was not (Table 5).

The mass resignation caused by the abrupt announcement of health policies led to significant changes in the hospital system, potentially affecting the quality of general surgery. The absence of junior doctors resulted in a major reduction in manpower, forcing hospitals to reduce the number of surgeries performed. Despite this, our study found no impact on the postoperative outcomes.

Several factors may explain why complications did not differ significantly between the crisis and control periods. First, the number of operations per day decreased from approximately 3 to 1, which might have allowed the operating surgeon to focus more effectively on each procedure. This suggests that optimizing the number of surgeries per day could be beneficial for ensuring adequate patient care and reducing physician workload, thereby minimizing the risk of medical errors. Second, during the months of March, April, and May—when most data were collected—the medical crisis was in its early stages. This period of transition allowed specialists to manage the increased workload, with the faculty and remaining fellows compensating for the absent junior doctors. Thus, hospital operations were sustained, and potential complications were mitigated after the mass resignation, rendering patient outcomes between the periods statistically insignificant.

Despite the lack of statistical significance, the observed decrease in operation duration is notable. During the control period, residents took turns as surgical assistants for different faculty members. Conversely, during the crisis period, a fixed specialized assistant supported the faculty member, which potentially improved synchronization and efficiency. Moreover, the absence of residents reduced the time previously allocated to their education, contributing to shorter operation durations.

Although the decrease in hospital stays was statistically insignificant, it remains an interesting observation. Residents play a larger role in postoperative care than in the surgical process itself. This finding may suggest that postoperative care at the hospital was insufficient during the crisis period.

However, some concerns remain. The education of junior doctors, which is crucial for the future healthcare workforce in Korea, has not been addressed, posing challenges in maintaining the country’s high-quality healthcare system. Moreover, the reduced number of operations has led to significant financial deficits for most hospitals, with the risk of bankruptcy for tertiary training hospitals. Additionally, the high workload on remaining healthcare providers threatens the system’s sustainability and may reduce patient care capacity. Addressing these issues is critical in preventing systemic collapse.

This study had several limitations. As a single-center, single-surgeon study, it may not represent the surgical outcomes of other hospitals or surgeons. Complications could vary with different surgical procedures, levels of resident involvement, or professional expertise among surgeons. Future studies focusing on surgeries that extensively require resident and intern involvement, or a nationwide study would be necessary to assess the broader impact of the resignation on the medical system. During the medical crisis period, junior doctors were replaced by highly experienced surgical assistants (with over 10 years of experience); studying hospitals without such assistants would more accurately reveal the impact of the absence of junior doctors.

During the crisis period, there were no patients with an ASA classification III (Table 1). This absence might initially suggest that surgeons were avoiding difficult cases. However, Korean medical law generally does not allow surgeons to refuse patients, making it challenging for them to selectively avoid high-risk cases. Therefore, the absence of patients with an ASA classification III in Table 1 is likely coincidental, as the overall number of patients decreased during the crisis period, reducing the likelihood of encountering patients with an ASA classification III. Another thing to consider is that the medical crisis impacted the entire nation; the hospitals, surgeons, or anesthesiologists might have subconsciously opted to avoid more complex cases.

Despite these limitations, this study pioneers the evaluation of surgical outcomes following the mass resignation of junior doctors in South Korea in 2024.

In conclusion, despite the medical crisis in South Korea, patient outcomes for gastric cancer surgery were stable in terms of the frequency of postoperative complications.