Timing of laparoscopic appendectomy and impacts on outcomes: A retrospective study of patients across in-hours, after-hours and holidays

Abstract

BACKGROUND

Acute appendicitis is a common surgical emergency, and appendectomy is essential to prevent complications such as perforation and peritonitis. Although the procedure is routine, outcomes may be affected by surgery timing, staffing, and hospital resources. Evidence on whether off-hour operations increase complications is conflicting. This study aimed to assess whether laparoscopic appendectomy performed during weekday in-hours, after-hours, or holiday periods influences postoperative outcomes.

AIM

To investigate clinical outcomes of laparoscopic appendectomy performed during weekday daytime, weekday evening, and weekends or holidays.

METHODS

The data of 977 patients who underwent laparoscopic appendectomy in a high-volume tertiary hospital between January 1, 2024, and December 31, 2024, were recruited. Patients were divided into three groups including surgeries during regular weekday in-hours (group 1), during weekday after-hours (group 2) and during weekends or extended holiday periods (group 3). Demographic, peri-, and postoperative data were compared.

RESULTS

There were no significant differences in operative time, conversion to open surgery, or complication rates between all groups. However, patients in the weekend/holiday group had significantly shorter time to surgery (median: 584 minutes vs 589 minutes vs 535 minutes, P = 0.002), and patients in the weekday in-hours group had significantly longer hospital stays than the other groups (median: 2 days vs 1 day vs 1 day, P < 0.001). No mortality occurred in any group.

CONCLUSION

In a well-staffed center, laparoscopic appendectomy during weekends or holidays is safe and may offer faster surgical access. Delay to surgery, not the working hour, is the main factor affecting outcomes.

Key Words: Laparoscopic appendectomy; Surgery timing; Weekend effect; Hospital stay; Surgical delay

Core Tip: The timing of laparoscopic appendectomy-whether during in-hours, after-hours, or weekends-does not negatively influence outcomes in well-organized tertiary centers. When performed in adequately staffed settings, weekend or holiday procedures are safe and may even allow faster surgical access. The principal factor affecting patient outcomes is surgical delay rather than the specific working hour.

INTRODUCTION

Acute appendicitis is one of the most common causes of emergency abdominal surgery worldwide. It occurs in about 200 cases per 100000 people, with a lifetime risk of roughly 9% in males and 7% in females[1,2]. In the United States, the lifetime risk ranges from 7% to 8%, while in South Korea it reaches 16%[3,4]. Early diagnosis and prompt surgery are essential to prevent complications like perforation, abscess, or peritonitis. Although appendectomy is a standard procedure, outcomes can be influenced by factors such as the timing of surgery, hospital staffing, and available resources[5,6]. Some research suggests delaying surgery in uncomplicated cases doesn’t increase risks, but other studies show postponing can raise the chances of perforation and other issues[7-10]. Therefore, the timing of surgical intervention is crucial[11,12].

Previous research indicates that surgeries conducted outside regular hours may lead to higher complication rates, longer hospital stays, and increased healthcare costs. These negative outcomes are often linked to lower staffing levels, healthcare worker fatigue, and limited access to diagnostic and support services during off-hours[10,13,14]. Nonetheless, the literature remains mixed, with some studies finding no significant difference in patient outcomes based on surgical timing. Many hospitals operate on shift systems during off-duty periods, resulting in variations in staffing, work hours, and hospital operations compared to regular hours[15]. Long shifts, fatigue, sleep deprivation, and reduced focus can impair clinical performance, potentially affecting outcomes for patients requiring emergency surgery[16,17].

This study aimed to assess how the timing of surgery influences clinical outcomes in patients undergoing appendectomy. We compared those operated on during regular weekday hours with those operated on at night or during extended public holidays. By examining various perioperative and postoperative factors across these groups, we aimed to understand if surgery timing impacts complication rates, hospital stays, and overall patient outcomes.

MATERIALS AND METHODS

The study protocol received approval from the Ethics Committee of Cam and Sakura City Hospital (Approval Code: 2025/151, Approval Date: 07 May 2025). It was conducted in accordance with the ethical principles of the Declaration of Helsinki. All patients were informed about the surgical procedures prior to surgery and provided written informed consent.

This retrospective observational study took place at a single tertiary care center, analyzing patient records from January 1, 2024, to December 31, 2024. Eligible participants were patients aged 18 years or older who underwent laparoscopic appendectomy during this period. Exclusion criteria included patients under 18, those who had undergone an open appendectomy, and cases with missing data. General surgery specialists performed all surgeries.

Patients were categorized into three groups according to when their surgery took place.

Group 1 consisted of patients who had surgery during regular weekday in-hours (08:00 to 16:30) (n = 243).

Group 2 comprised patients who underwent surgery during weekday after-hours (16:30 to 08:00) (n = 332).

Group 3 consisted of patients who underwent appendectomy procedures during weekends or extended holiday periods (n = 402).

This classification sought to assess how the timing of surgery-especially during off-hours or holidays-affected clinical outcomes. It aimed to compare the results of laparoscopic appendectomies performed during regular weekday daytime hours with those done during nighttime shifts and extended public holidays.

Demographic and clinical data were retrospectively collected from hospital records. The data analyzed included age, sex, time from admission to surgery, duration of the procedure, intraoperative findings (perforated vs non-perforated appendix), presence of surgical drains, and conversion rates to open surgery. Additionally, radiological findings, histopathological results, intraoperative and postoperative complications, morbidity, mortality, and length of hospital stay were documented.

Statistical analysis

Descriptive statistics were employed to summarize the data. The Kolmogorov-Smirnov test was utilized to evaluate the normality of continuous variables. Data exhibiting a normal distribution were reported as mean ± SD, whereas non-normally distributed data were expressed as median and interquartile range (IQR). Categorical variables were presented as n (%). Inter-group comparisons were conducted using the χ² test or Fisher’s exact test for categorical variables, and the Kruskal-Wallis test or Mann-Whitney U test for continuous variables, as applicable. Bonferroni correction was implemented for post hoc pairwise comparisons. Multivariate logistic regression analysis was performed to assess the potential influence of age, sex, timing group, perforation status, operative time, and time-to-surgery on postoperative complications. A P value less than 0.05 was regarded as statistically significant. All statistical analyses were executed utilizing SPSS software (version 22.0; IBM Corp., Armonk, NY, United States).

RESULTS

A total of 977 patients were enrolled in the study. A flowchart of the patient selection and sampling process according to the STROBE guidelines is shown in Figure 1. The distribution of demographic and perioperative variables is summarized in Table 1. There was no statistically significant difference in sex distribution among the groups (P = 0.297). The median age was 36 years (range: 18-91) in Group 1, 30 years (range: 18-78) in Group 2, and 32 years (range: 18-79) in Group 3.

Figure 1  A flowchart illustrating the patient selection and sampling process according to the STROBE guideline.

Table 1 Demographic and operative data of patients.

	Group 1 (n = 243)		Group 2 (n = 332)		Group 3 (n = 402)		P value
	n (%)	95%CI	n (%)	95%CI	n (%)	95%CI
Sex							0.297
Male	151 (62.1)	(55.9-68)	196 (59)	(53.7-64.2)	225 (56)	(51.1-60.7)
Female	92 (37.9)	(32-44.1)	136 (41)	(35.8-46.3)	177 (44)	(39.3-48.9)
Conversion to open surgery	3 (1.2)	(0.4-3.6)	6 (1.8)	(0.8-3.9)	13 (3.2)	(1.9-5.5)	0.202
Presence of surgical drains	235 (96.7)	(93.6-98.3)	328 (98.8)	(96.9-99.5)	392 (97.5)	(95.5-98.6)	0.229
Intraoperative findings							0.619
Perforated	13 (5.3)	(3.2-8.9)	15 (4.5)	(2.8-7.3)	15 (3.7)	(2.3-6.1)
Non- perforated	230 (94.7)	(91.1-96.9)	317 (95.5)	(92.7-97.2)	387 (96.3)	(93.9-97.7)
	Med (IQR)		Med (IQR)		Med (IQR)
Age1	36 (18-91)	32-38	30 (18-78)	29-33	32 (18-79)	30-34	0.240
Operative time (min)1	45 (35-65)	45-50	45 (31.25-60)	40-50	45 (35-65)	45-50	0.211

¹Data are presented as median (inter quantile range).

CI: Confidence interval: IQR: Inter quantile range.

Conversion to open surgery was necessary in 3 patients (1.2%) in Group 1, 6 patients (1.8%) in Group 2, and 13 patients (3.2%) in Group 3. This variation was not statistically significant (P = 0.202). The median operative time was consistent across all groups at 45 minutes, with IQR of 35-65 minutes for Group 1, 31.25-60 minutes for Group 2, and 35-65 minutes for Group 3 (P = 0.211). Surgical drains were utilized in 96.7%, 98.8%, and 97.5% of patients in Groups 1, 2, and 3, respectively (P = 0.229). Intraoperative observations indicated similar incidences of perforated and non-perforated appendicitis across all groups, with no statistically significant differences observed (P = 0.623) (Table 1).

The median time from admission to surgical intervention was significantly shorter in Group 3 than in Groups 1 and 2 (P < 0.05). Conversely, no statistically significant difference was identified between Groups 1 and 2 (P = 1.00) (Table 2).

Table 2 Clinical outcomes of patients.

	Group 1 (n = 243)		Group 2 (n = 332)		Group 3 (n = 402)		P value
	n (%)	95%CI	n (%)	95%CI	n (%)	95%CI
Intraoperative complication rate	0 (0)	0-1.6	0 (0)	0-1.1	1 (0.2)	0-1.4	0.489
Post-op complication	5 (2.1)	0.8-4.7	8 (2.4)	1.2-4.7	4 (1.0)	0.4-2.5	0.314
Mortality	0 (0)	0-1.6	0 (0)	0-1.1	0 (0)	0-0.1	1.00
	Med (IQR)		Med (IQR)		Med (IQR)
Time from the admission to surgery (minutes)1	584 (443-752)	557-628	589 (415.5-777.75)	558.5-629	535 (373-719.25)	502-564.5	0.002
							(1 vs 3:0.010)
							(2 vs 3:0.008)
							(1 vs 2: 1.00)
Length of hospital stay (day)1	2 (1-3)	1.0-2.0	1 (1-2)	1.0-1.0	1 (1-2)	1.0-1.0	< 0.001
							1 vs 2: < 0.001)
							(1 vs 3: < 0.001)
							(2 vs 3: 1.00)

¹Data are presented as median (inter quantile range).

CI: Confidence interval: IQR: Inter quantile range.

Intraoperative complications were infrequent, with only one case (0.2%) reported in Group 3. No complications were observed in Groups 1 or 2 (P = 0.489) (Table 2).

Postoperative complications occurred in 5 patients (2.1%) in Group 1, 8 patients (2.4%) in Group 2, and 4 patients (1.0%) in Group 3, with no significant difference (P = 0.314).

The duration of hospitalization exhibited significant variation among the groups (P < 0.001). The median length of stay was 2 days (IQR: 1-3) in Group 1, while it was 1 day (IQR: 1-2) in both Groups 2 and 3. Pairwise comparisons indicated that Group 1 experienced notably longer hospital stays compared to Groups 2 and 3 (P < 0.001), whereas no statistically significant difference was identified between Groups 2 and 3 (P = 1.00). Additionally, no cases of in-hospital mortality were observed across any of the groups (Table 2).

Table 3 presents the distribution of postoperative complications. A total of 17 patients experienced postoperative issues, with the most common being intra-abdominal abscess, abdominal hemorrhage, post-operative ileus, and surgical site infections (SSI). The overall complication rates were 2% in group 1, 0.24% in group 2, and 0.08% in group 3. No significant differences were found in the distribution of complications across the groups.

Table 3 Postoperative complications, n (%).

	Group 1 (n = 243)	Group 2 (n = 332)	Group 3 (n = 402)	P value
Intra-abdominal abscess	3 (1.2)	6 (0.18)	1 (0.02)
Hemorrhage	1 (0.04)	0	1 (0.02)
Post-op ileus	1 (0.04)	1 (0.03)	1 (0.02)
SSI (subcutaneous)	0	1 (0.03)	1 (0.02)
Total	5 (2)	8 (0.24)	4 (0.08)	0.314

SSI: Surgical site infection.

In addition to the univariate analyses, a multivariate logistic regression was performed to identify independent predictors of postoperative complications. The model included variables such as timing group, age, gender, time from admission to surgery, operative time, and intraoperative findings (presence of perforated or non-perforated acute appendicitis). Of these factors, only perforation status proved statistically significant (P = 0.009). Specifically, perforated appendicitis was associated with a sixfold increased risk of postoperative complications compared to non-perforated cases (Table 4).

Table 4 Multivariate logistic regression analysis of factors associated with postoperative complications.

Variable	OR (95%CI)	P value
Group (ref: Group 1)
Group 2	1.209 (0.379-3.858)	0.748
Group 3	0.516 (0.133-2.009)	0.340
Age	0.970 (0.931-1.010)	0.137
Gender (ref: Male)
Female	0.860 (0.299-2.476)	0.780
Time from the admission to surgery (min)	1.000 (0.999-1.001)	0.502
Operative time	1.010 (0.993-1.028)	0.253
Intraoperative findings (ref: Non-perforated)
Perforated	6.022 (1.566-23.155)	0.009

DISCUSSION

Acute appendicitis is a common surgical emergency that can be either simple or complicated, such as phlegmon or appendiceal abscess. Surgery is the gold standard for treatment, but the best timing for appendectomy remains uncertain. Several studies have shown that hospital operations often vary between regular working hours and outside those hours, including evenings, weekends, and public holidays[18,19]. During these times, hospitals typically operate with fewer staff and resources due to shift systems[15]. Healthcare workers are more likely to experience long hours, fatigue, and sleep deprivation during these periods, which can negatively affect their clinical performance[16]. These issues can impact diagnostic accuracy, decision-making, and surgical outcomes, especially in emergencies[12,17]. A time-dependent increase in complication or perforation rates has been observed with in-hospital delays of 6 to 48 hours[9,13,14,20]. In countries with frequent and long public holidays, the effect of out-of-hours hospital operations might be even more significant. Holidays often disrupt everyday hospital workflows, prompting questions about whether they also affect emergency department activities. Such changes are believed to cause delays in diagnosis or surgery and decrease the quality of operative care. Few studies have directly examined how holiday-related delays influence surgical outcomes during extended holiday periods in these healthcare systems[11,19].

This study aimed to assess whether the timing of surgery affects clinical outcomes in patients undergoing laparoscopic appendectomy during weekday in-hours, weekday after-hours, and weekends or long public holidays. By examining perioperative and postoperative variables across these groups, we sought to determine whether operative timing is associated with differences in complication rates, length of hospital stay, or overall patient outcomes. These results will help establish staffing policies and workflow planning in emergency surgical care.

Several studies have examined how the timing of surgery affects the outcomes of laparoscopic appendectomy. Kim and Kang[21] reported no significant differences in operative time, complications, or recovery between surgeries performed during or after hours. The day of discharge was not associated with higher readmission rates[22]. Consistent with this, Shen et al[18] and Mönttinen et al[23] found that outcomes did not significantly differ between daytime and nighttime procedures. Lane et al[24] also observed no significant differences between weekday and weekend cases, except for a slightly higher rate of SSI in weekday patients. A similar finding was noted in a study that grouped surgeries by time of day, which showed no difference unless the operation was delayed by more than 24 hours[10].

Other research emphasizes the risks associated with delayed surgery. Al-Qurayshi et al[9] found that delays and weekend admissions were associated with longer hospital stays and increased complications. A large-scale analysis of over 855000 cases indicated that delaying surgery beyond 12 hours in complex cases and 24 hours in simpler cases significantly increased the risk of adverse outcomes[7]. Hospital resources and staffing levels also play a critical role. Ozdemir et al[15] observed higher weekend mortality rates in hospitals with fewer staff. Our results support the view that surgery delays, rather than the timing within the day or week, primarily influence outcomes. While perforation rates showed no significant difference, earlier surgeries demonstrated a positive trend, consistent with Drake et al[25], who reported that performing surgery within 8.6 hours helps prevent perforation.

Our study, conducted at a busy tertiary hospital with 977 patients, categorized patients by the timing of their surgery: Weekday in-hours (Group 1), weekday after-hours (Group 2), or weekend or holiday (Group 3). We observed that Group 3 patients had a significantly shorter interval from admission to surgery than the other groups. However, there was no significant difference in overall complication rates among the groups, and no mortalities occurred in any group. Operative time, conversion to open surgery, drain use, and intraoperative findings showed no significant differences across groups. Despite concerns about weekend surgeries, our findings suggest that patients undergoing surgery on weekends or holidays may benefit from quicker access to surgery. Reduced elective procedures during these times likely facilitate faster emergency care. Several meta-analyses and large-scale studies have reported higher rates of after-hours surgeries, increased mortality, morbidity, complications, and longer wait times-in what is often called the “weekend effect”[26-29]. It's thought that limited healthcare services on weekends contribute to these outcomes. Some argue that the negative consequences of adverse events cannot be offset by increasing workload in subsequent days. Enhancing efforts to ensure consistent quality of care across all days is crucial, and identifying system deficiencies is key[30,31]. Interestingly, unlike previous studies, our research found shorter time-to-surgery during holidays. This may be due to the organizational features of our tertiary-care hospital, which has a team of attending surgeons and residents with defined roles, along with well-staffed anesthesia and nursing teams. Dedicated operating rooms are maintained for emergency cases, allowing rapid coordination and prompt intervention. When a patient with suspected surgical issues presents at the emergency department, they are quickly evaluated, and once surgery is needed, the surgical, anesthesia, and nursing teams are promptly mobilized. This effective combination of staffing, operating room readiness, and emergency triage seems to reduce or even eliminate delays commonly associated with the weekend effect. This organizational setup can be considered a strength of our national healthcare system.

This study has several limitations. First, it was conducted in a single, well-equipped tertiary hospital. Consequently, these findings may not be generalizable to smaller or resource-limited centers. Second, the retrospective nature of the study design limits our ability to establish causal relationships and account for all confounding variables, such as comorbidities or reasons for delays. Third, the surgical teams were not standardized; although all surgeons had specialized training, variations in experience and decision-making could influence outcomes.

CONCLUSION

At a well-equipped center, laparoscopic appendectomies performed on weekends and holidays proved to be safe and effective. Patients experienced shorter intervals from admission to surgery and shorter hospital stays than those operated on weekdays during working hours. Our findings challenge the assumption that weekend surgeries carry higher risks. Instead, they highlight a more crucial point: The timing of the surgery-specifically, how long the appendix remains untreated-is more important than the day of the week.