The first minimally invasive surgery (MIS) was attempted by Georg Kelling in 1901. However, we had to wait for the development of the computer chip television in the late 1980s to make the first successful laparoscopic cholecystectomy [1]. The laparoscopic cholecystectomy rapidly grew in popularity but there were many questions about its safety compared with the “gold standard” of open cholecystectomy [2]. The same pictures were seen in other general surgery procedures including appendectomy, colectomy, and herniorrhaphy [3]. With additional experience, training, and improvement of surgical instruments, the early “learning curve” injuries were decreased [4]. Nowadays, MIS offers patients several benefits, such as smaller incisions, fast recovery times, and reduced pain/scarring. Each general surgery training center should verify that their residents have adequate knowledge and skills to perform both open and laparoscopic surgery safely.

There was a decline in open surgical experience for general surgery residents from 2000 to 2017 in the United States [5]. Faculty staff should be concerned that residents may be insufficiently exposed to open and laparoscopic techniques in some procedures [6]. However, there is a lack of vigorous data describing the operative experiences during surgery residency training outside of the United States [7]. In Thailand, there are some reports in general surgery trainee’s operative experience; but they are out of date and insufficient for comparing between open and laparoscopic procedures [8]. The laparoscopic procedure has become a gold standard in many organ systems, such as cholecystectomy, adrenalectomy, and appendectomy [9]. We aimed to figure out the trend of MIS experience of general surgery residents in Thailand.

A retrospective review of the Royal College of Surgeons of Thailand (RCST) electronic logbook from 2007 to 2018 was performed for common open and laparoscopic general surgery operations as an assistant or operating surgeon. Cholecystectomy, appendectomy, and hernia surgery experience were assessed for trends in the number of procedures performed by the resident each year. We compared the Accreditation Council for Graduate Medical Education (ACGME) general surgery case logs statistical report from the academic year 2007 to 2018, which was the number of operations performed by graduating general surgery residents in the United States. However, before comparison, we divided the numbers of ACGME general surgery case logs statistical reports by 5 to make the data similar to the results from RCST as much as possible.

The data were separated into three groups: period 1, 2007–2010; period 2, 2011–2014; and period 3, 2015–2018. The changes in the average number of operative experiences per year per person between periods were compared by using an analysis of variance. Results with a p-value of less than 0.05 were considered to be statistically significant. STATA software version 10 (StataCorp LLC) was used for statistical analysis.

In Thailand, the total average number of cases of appendectomy, cholecystectomy, and hernia surgery increased from 26.86 in 2007 to 34.97 in 2018 (an increase of 30.19%). The total average number of cases performed laparoscopically increased from 6.04 to 9.16 (an increase of 51.66%) and open increased from 20.82 to 25.81 (an increase of 23.97%) (Table 1). There was a decrease in the average number of open procedures among cholecystectomy and appendectomy in the United States (10.6 to 8.4, 23.9 to 5.6). In contrast, the average number of selected laparoscopic procedures increased every year (Table 2).

In Thailand, the number of open appendectomies had a significant increase in each period. There was a decrease in the number of open cholecystectomies from period 1 to period 2 and an increase from period 2 to period 3. However, there was no statistical significance (3.27, 3.16, 3.49; p = 0.075). The same picture was seen in open hernia surgery, there was a decrease from period 1 to period 2 and an increase from period 2 to period 3 without statistical significance (6.48, 6.14, 6.30; p = 0.4838). The total number of laparoscopic cholecystectomy and minimally invasive hernia surgery performed had a significant increase in each period (5.83, 6.57, 8.10; p < 0.001). The change in laparoscopic appendectomy has fluctuated, there was a decrease from period 1 to 2 and an increase from period 2 to period 3 without statistically significant (0.21, 0.18, 0.26). There was a significant increase in the number of endoscopic retrograde cholangiopancreatography (ERCP) (0.56, 1.01, 1.88; p < 0.001). However, the number of open common bile duct exploration (OCBDE) procedures gradually decreased with statistical significance in Thai general surgery residents (0.80, 0.55, 0.38; p = 0.003) (Table 3).

In Thailand, the rate of laparoscopic cholecystectomy slightly increased from 64.33% in 2007 to 69.61% in 2018, parallel to the United States. However, among appendectomy and hernia surgery, the rate of procedures performed laparoscopically in Thailand was extremely low and only slightly increased. In contrast, the rate of laparoscopic appendectomy in the United States dramatically increased from 53.68% to 91.85% within 12 years. The rate of hernia surgery performed laparoscopically gradually increased from 23.82% in 2007 to 44.17% in 2018 (Fig. 1). Overall, Thai general surgery residents have more experience with open appendectomy and ERCP, but significantly less experience with all other operations/procedures.

MIS increases in popularity every day. The results of MIS were comparable to open surgery in terms of effectiveness. In addition, MIS offers smaller incisions, fast recovery times, and reduced postoperative pain [10]. Each training center should provide both open and minimally invasive experiences for general surgery residents to fulfill the patients’ needs.

In Thailand, the overall operative experience in both open and MIS increased every year in the past 12 years. The number of MIS experiences rose by over 50% during this period. However, the overall MIS experience was still low when compared to the United States general surgery residents [5].

Thai general surgery residents had a significant increase in the number of laparoscopic cholecystectomy experiences. It slightly increased the rate of laparoscopic cholecystectomy experience from 65% to 70%. The rate of laparoscopic cholecystectomy in the United States resident remains stable at around 90%. Although laparoscopic cholecystectomy has several benefits and can be performed safely by general surgery residents [11]. Being able to convert from a laparoscopic approach to open surgery is very important for a competent surgeon [12–14]. As a training center, we have to make sure that our general surgery residents are also comfortable doing open cholecystectomies.

The rate of laparoscopic appendectomy in the United States residents increased moderately from 50% to 90%. There were several data indicating resident-performed laparoscopic appendectomies were safe [15,16]. This procedure can also stimulate surgical autonomy in laparoscopic surgery [17]. However, the percentage of laparoscopic appendectomy performed by general surgery residents in Thailand remained stable at near zero.

Laparoscopic hernia repair is an alternative to standard open inguinal hernia repair. It is associated with less postoperative pain and a quicker return to normal activity. Laparoscopic herniorrhaphy may offer several benefits for patients with bilateral or recurrent inguinal hernias [18]. Teaching and mentoring residents in the operating room for laparoscopic hernia repair are safe [19]. However, the percentage of laparoscopic hernia repair in Thai residents grew slowly when compared to the United States residents.

Nowadays, ERCP followed by laparoscopic cholecystectomy and laparoscopic common bile duct exploration are the two most popular methods in the management of choledocholithiasis. Both procedures show promising results without significant differences in success rate, mortality, and morbidity [20]. In Thailand, the number of ERCP procedures has significantly increased following global trends. On the other hand, the number of residents’ experiences in OCBDE has declined significantly as same as the previous study in the United States [21,22]. A novel simulation including fresh cadavers should be considered to enhance the open surgery skill to alleviate the loss of low-volume, complex procedures.

Both open and laparoscopy skills are very important for general surgeons. In the United States, there was a problem of reduction in the volume of open procedures performed by general surgery residents [5,23,24]. However, Thai general surgery residents had far less experience in MIS, especially in laparoscopic appendectomy and laparoscopic hernia repair. It would be better for general surgery resident to get a well-balanced distribution of open and basic laparoscopic procedures during their residency training [25]. There are several options, including cadaver workshops, skill evaluations, and a set of optimum operative procedures required to increase surgical experience [26–28]. The RCST should revise the curriculum to enhance these laparoscopic surgery skills to match the trends in MIS.

There were various limitations to this study. First, the recorded data from Thailand and the United States were different. In Thailand, the logbook recorded the number of procedures performed by 1st- to 4th-year general surgery residents each year. At the same time, the United States case log showed the average number of specific operations per resident through the entire training, from the first through the final year. Second, there was a difference in the length of training; Thai surgery residency mostly requires 4 years of training, while the United States requires a minimum of 5 years. Third, Thai and American curricula had different minimal requirements; the Thai curriculum only required 100 procedures performed as operating surgeon for each resident, while the United States curriculum required each resident to perform at least 850 procedures. Fourth, these factors might explain the vast difference in the case numbers performed by Thai and United States residents. In addition, only laparoscopic cholecystectomy, appendectomy, and hernia repair procedures were available for comparison. Both general surgery residents from Thailand and the United States manually recorded the logs by themselves; thus, the number of procedures recorded and the authenticity of data might be inaccurate [29]. The differences in healthcare systems, medical infrastructure, and socioeconomic factors might also contribute to the differences between Thailand and the United States [30]. However, we needed access to these data to perform a comparative analysis.

In conclusion, the number of open- and minimally invasive procedures performed or assisted by Thai general surgery residents is slowly increasing but generally lags behind United States residents. The Thai education program must be updated to improve residents’ technical skills in open and laparoscopic surgery, aligning with global trend.

Ethical statements

We conducted this study in compliance with the principles of the Declaration of Helsinki. The study’s protocol was reviewed and approved by the Institutional Review Board of Khon Kaen University Ethics Committee (No. HE631151). Written informed consent was waived.

Authors’ contributions

Conceptualization: CE, JW, KE, TS, DG, RP

Data curation: CE, PA

Methodology: CE, KE, EP, DG, RP

Formal analysis: CE, EP

Investigation, Visualization: CE

Software: PA

Supervision: SR, KJ

Writing–original draft: CE

Writing–review & editing: JW, KE, TS, SP, RP

All authors read and approved the final manuscript.

Conflict of interest

All authors have no conflicts of interest to declare.

Funding/support

None.

Data availability

The data presented in this study are available on request from the corresponding author.

The average number of procedures performed by general surgery residents per person in each year of training in Thailand

The average number of procedures performed by general surgical residents per a person in each year of training in the United States

The average number of procedures performed by general surgery residents per a person compared over three periods in Thailand