Outcomes in Minimally Invasive Sleeve Gastrectomy and Implications for Surgical Resident Education

Abstract

Introduction:

Resident participation in advanced minimally invasive and bariatric surgeries is controversial. The aim of this study is to evaluate the safety of resident participation in robotic and laparoscopic sleeve gastrectomy (SG).

Methods:

Prospectively maintained institutional Metabolic and Bariatric Surgery Accreditation Quality Improvement Program database was used to identify patients who underwent SG, which was performed at our institution between January, 2018, and December, 2021. Operative notes were reviewed to determine the training level of the assistant. These were then classified into 7 groups: postgraduate years 1–5 residents, bariatric fellow (6), and attending surgeons (7). Each group was stratified and their outcomes, which included duration of surgery, length of stay (LOS), postoperative complications, readmissions, and reoperations, were compared.

Results:

Out of 2571 cases, the assistants for the procedures were minimally invasive surgery (MIS) fellows (n = 863, 58.8%), fifth- and fourth-year residents (n = 228, 15.5%), third- and second-year residents (n = 164, 11.2%), no assistants (n = 212, 14.5%), and 134 robotic SG. Mean body mass index was higher in cases wherein the attending surgeon performed by himself (47.1, standard deviation 7.7) when compared with other groups. There were no conversions to open. Mean LOS was 1.3 days, and there was no difference between groups (P = .242). Postoperative complications were low, with 11 reoperations in 30 days (3.3%) and no difference between groups. There was no mortality in 30 or 90 days.

Conclusion:

Postoperative outcomes were similar for patients who underwent SG regardless of the assistant's level of training. Including residents in bariatric procedures is safe and does not affect patient safety. Encouraging residents to participate in complex MIS procedures is recommended as part of their training.

Introduction

The incidence of obesity is increasing in the United States. As such, there has been a concomitant increase in the number of bariatric procedures performed each year.¹ Bariatric surgery is currently the gold standard in the treatment of morbid obesity and its related complications. In fact, metabolic surgery is very effective in increasing life expectancy and improving obesity-related comorbidities, such as hypertension, diabetes mellitus (DM), and dyslipidemia.²

The most common bariatric procedures currently performed in the United States are sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB).³ In the past decade, there has been an increasing shift toward laparoscopic SG, which can be part of a staged approach in high-risk patients or as a standalone procedure.^4,5 Despite their popularity, bariatric procedures are technically complex and can have very morbid complications, which can be challenging for early or inexperienced surgeons. Fellowship training has been associated with improved surgical outcomes and, therefore, has become a significant requirement for establishing and maintaining a bariatric practice in the United States.^6–8

Multiple authors have studied resident participation in the safety and outcomes of a wide range of surgical procedures within different subspecialties.^9–12 The model of graduated autonomy in both patient care and surgical participation is widely accepted. However, the implications related to this model of training have not been broadly discussed in the literature.¹ The aim of this study is to use our institutional Metabolic and Bariatric Surgery Accreditation Quality Improvement Program (MBSAQIP) database to evaluate the safety of active resident participation in laparoscopic or robotic SG.

Methods

Data collection

The MBSAQIP Data Registry is a prospectively collected database that includes patient demographics, perioperative information, and postoperative morbidity and mortality data. This study was conducted by pooling in patients who underwent laparoscopic or robotic SG at our institution between January, 2018, and December, 2021, using the MBSAQIP database. All patients underwent an intense preoperative bariatric program with a multidisciplinary team.

Baseline demographics included gender, age, body mass index (BMI), American Society of Anesthesiologists (ASA) class, smoking status, DM, hypertension, chronic obstructive pulmonary disease, sleep apnea, steroid use, myocardial infarction, dyslipidemia, use of anticoagulants, and gastroesophageal reflux disease.

The level of training of the assistants was also evaluated, which ranged from postgraduate year (PGY) 1 residents to a minimally invasive surgery (MIS) fellow. Perioperative and postoperative data were collected, that is, surgical approach (laparoscopic or robotic), operative time (OT), length of stay (LOS), and complications such as gastrointestinal bleeding, surgical site infection (SSI), emergency department (ED visits), readmissions within 30 days, reoperations within 30 days, deep venous thrombosis (DVT), acute renal failure, blood transfusion, mortality in 30 and 90 days, sepsis, pneumonia, and unplanned admission to the intensive care unit.

Sleeve gastrectomy in our academic institution

Residents at all levels of training are exposed to bariatric surgery in our institution. They actively participate with the surgical team and often perform surgical steps concordant to their skillset, familiarity with the procedure, and difficulty of the case. Naturally, more experienced residents can perform significant portions of the surgery, but junior residents are often able to actively participate in a majority of the cases with appropriate guidance. SG has been advertised in the past as a simple and fast procedure, but it can be challenging even for experienced surgeons.

All procedures were performed with the MIS approach and the same surgical technique was used by 5 different surgeons, with minimal differences, such as the use of a fibrin sealant in the staple line or sewing the staple line with omentum. All trainees had access to laparoscopic and robotic simulators and all patients were managed in the same way in the perioperative period.

Statistical analysis

Categorical variables have been presented as frequencies and percentages, and continuous variables have been presented as mean and standard deviation. Univariate analyses were performed using Pearson's chi-squared test for categorical variables and the Kruskal–Wallis test for continuous variables. A P value <.05 was considered significant. Statistical analysis was performed using SPSS software, version 28 (IBM© www.ibm.com). Approval for this study was obtained through the institutional review board (IRB 2022-13755) and all Health Insurance Portability and Accountability Act (HIPAA) procedures were followed. Written consent was not needed.

Results

A total of 2571 patients underwent minimally invasive SG in our academic center between January, 2018, and December, 2021. Mean age was 39.2 years (±12.2), and 2140 (83.2%) patients were women. Patient characteristics are listed in Table 1. Most patients were ASA II (549; 21.4%) or ASA III (2005; 78%). In total, 2426 (94.4%) patients underwent the laparoscopic approach.

Table 1.

Patient Characteristics

n = 2571	n (%)
BMI^a	45.6 (8)
Age^a	39.2 (12.2)
LOS^a	1.3 (0.7)
OT^a	79.3 (39.2)
Gender
Women	2140 (83.2)
Men	431 (16.8)
Smoker	174 (6.8)
DM
Noninsulin dependent	310 (12.1)
Insulin dependent	148 (5.8)
Steroid/immunossupression	32 (1.2)
COPD	28 (1.1)
Sleep apnea	808 (31.4)
GERD	349 (13.6)
Myocardial infarct	17 (0.7)
Hypertension	875 (34)
Dyslipidemia	369 (14.4)
Anticoagulation	40 (1.6)
ASA
ASA I	1 (0)
ASA II	549 (21.4)
ASA III	2005 (78)
ASA IV	15 (0.6)
Surgical approach
Laparoscopic	2426 (94.4)
Robotic	145 (5.6)

Mean (SD).

ASA, American Society of Anesthesiologists; BMI, body mass index; COPD, chronic obstructive pulmonary disease; DM, diabetes mellitus; GERD, gastroesophageal reflux disease; LOS, length of stay; OT, operative time; SD, standard deviation.

Regarding level of training, most procedures were assisted by MIS fellows (979; 28.1%), followed by PGY-4 residents (546; 21.2%), attending surgeons (502; 19.5%), and PGY-2 residents (390; 15.2%) (Table 2). Surgeons operated in patients with higher BMI and ASA III when compared with other groups (Table 3). MIS fellows and attending surgeons also performed most robotic surgeries. Mean OT was 79.3 minutes (±39.2). When stratified by groups, there was no difference between groups (Table 4).

Table 2.

Surgical Cases by Postgraduate Year Residents

n = 2571	n (%)
PGY level
PGY 1	42 (1.6)
PGY 2	390 (15.2)
PGY 3	51 (2)
PGY 4	546 (21.2)
PGY 5	61 (2.4)
Fellow	979 (38.1)
Attending surgeon	502 (19.5)

PGY, postgraduate year.

Table 3.

Patient Characteristics by Postgraduate Year residents, Fellow, and Attending Physician

	PGY 1 n = 42	PGY 2 n = 390	PGY 3 n = 51	PGY 4 n = 546	PGY 5 n = 61	Fellow n = 979	Attending physician n = 502	P
Mean age (SD)	37.2 (10.6)	39.1 (11.8)	38.1 (13.6)	40 (11.8)	38.3 (11.8)	39.2 (12.5)	38.9 (12.6)	.534
Mean BMI (SD)	45.1 (7.8)	45.6 (8.3)	43 (6.2)	44.9 (7.2)	44.3 (6.7)	45.3 (7.7)	47.6 (9.1)	<.001
Mean LOS (SD)	1.4 (0.5)	1.4 (0.7)	1.5 (0.8)	1.5 (1)	1.6 (0.8)	1.3 (0.7)	1.4 (0.7)	<.001
Gender, n (%)								.114
Women	39 (92.9)	320 (82.1)	45 (88.2)	456 (83.5)	56 (91.8)	820 (83.8)	404 (80.5)
Men	3 (7.1)	70 (17.9)	6 (11.8)	90 (16.5)	5 (8.2)	159 (16.2)	98 (19.5)
Smoker	2 (4.8)	31 (7.9)	5 (9.8)	30 (5.5)	4 (6.6)	62 (6.3)	40 (8)	.58
DM, n (%)								<.001
No	33 (78.6)	327 (83.8)	46 (90.2)	448 (82.1)	53 (86.9)	800 (81.7)	406 (80.9)
Noninsulin dependent	6 (14.3)	44 (11.3)	5 (9.8)	72 (13.2)	8 (13.1)	95 (9.7)	80 (15.9)
Insulin dependent	3 (7.1)	19 (4.9)	0	26 (4.8)	0	84 (8.6)	16 (3.2)
COPD	0	5 (1.3)	1 (2)	7 (1.3)	1 (1.6)	9 (0.9)	5 (1)	.951
Sleep apnea	16 (38.1)	135 (34.6)	15 (29.4)	164 (30)	19 (31.1)	293 (29.9)	166 (33.1)	.551
GERD	4 (9.5)	47 (12.1)	7 (13.7)	92 (16.8)	8 (13.1)	129 (13.2)	62 (12.4)	.308
Myocardial infarction	0	2 (0.5)	0	5 (0.9)	0	8 (0.8)	2 (0.4)	.859
Hypertension	8 (19)	126 (32.3)	13 (25.5)	197 (36.1)	20 (32.8)	340 (34.7)	171 (34.1)	.265
Dyslipidemia	4 (9.5)	44 (11.3)	4 (7.8)	95 (17.4)	11 (18)	152 (15.5)	59 (11.8)	.28
Anticoagulation	0	5 (1.3)	0	9 (1.6)	1 (1.6)	16 (1.6)	9 (1.8)	.927
ASA, n (%)								.028
I	0	0	0	0	0	0	1 (0.2)
II	15 (35.7)	87 (22.3)	19 (38)	131 (24)	16 (26.2)	189 (19.3)	92 (18.3)
III	26 (61.9)	300 (76.9)	31 (60)	411 (75.3)	45 (73.8)	784 (80.1)	408 (81.3)
IV	1 (2.4)	3 (0.8)	1 (2)	4 (0.7)	0	6 (0.6)	1 (0.2)
Surgical approach, n (%)								<.001
Laparoscopy	37 (88.1)	359 (92.1)	51 (100)	528 (96.7)	61 (100)	928 (94.8)	462 (92)
Robotic	5 (11.9)	31 (7.9)	0	18 (3.3)	0	51 (5.2)	40 (8)

Table 4.

Perioperative Outcomes

	PGY 1 n = 42	PGY 2 n = 390	PGY 3 n = 51	PGY 4 n = 546	PGY 5 n = 61	Fellow n = 979	Attending physician n = 502	P
ED visits	3 (7%)	25 (6%)	6 (12%)	40 (7%)	7 (11%)	65 (7%)	45 (9%)	.417
Readmission within 30 days	1 (2%)	13 (3%)	1 (2%)	12 (2%)	4 (7%)	24 (2%)	17 (3%)	.478
Reoperations within 30 days	1 (2%)	2 (0.5%)	1 (2%)	3 (0.5%)	3 (5%)	1 (0.1%)	2 (0.3%)	.453
Unplanned intervention within 30 days	2 (0.4%)	1 (0.2%)	1 (2%)	2 (0.3%)	0	1 (0.1%)	1 (0.1%)	.242
Mean OT (SD)	73 (42.5)	79.6 (39.7)	80 (30.4)	81 (43.1)	73.9 (32.5)	80.4 (39)	76.5 (36.1)	.373

ED, emergency department; OT, operative time; PGY, postgraduate year; SD, standard deviation.

There were 191 (7.4%) ED visits, 72 (2.8%) readmissions within 30 days, 13 (0.5%) reoperations within 30 days, and only 6 (0.2%) unplanned interventions within 30 days. There was no difference between the groups when comparing these outcomes (Table 4). There were 18 (0.7%) patients who required blood transfusion, 8 (0.3%) DVTs, 7 (0.3%) patients with pneumonia, and 9 (0.4%) patients with urinary tract infection (UTI), with no difference between the groups (Table 5). There was no conversion to open surgery and no mortality in 30 days.

Table 5.

Postoperative Outcomes

	PGY 1 n = 42	PGY 2 n = 390	PGY 3 n = 51	PGY 4 n = 546	PGY 5 n = 61	Fellow n = 979	Attending physician n = 502	P
UTI	1 (2.4)	2 (0.5)	0	0	1 (1.6)	3 (0.3)	2 (0.4)	.111
Acute renal failure	0	0	1 (2)	0	1 (1.6)	1 (0.1)	0	1
Blood transfusion	0	5 (1.3)	0	4 (0.7)	0	8 (0.8)	1 (0.2)	.544
GI bleeding	0	2 (0.5)	0	0	0	0	1 (0.2)	.3
Unplanned admission to ICU	0	0	0	0	1 (1.6)	1 (0.1)	1 (0.2)	.34
Pneumonia	0	2 (0.5)	0	0	1 (1.6)	3 (0.3)	1 (0.2)	.329
Sepsis	0	1 (0.3)	0	0	0	1 (0.1)	0	.856
Septic shock	0	0	1 (2)	0	0	0	0	1

GI, gastrointestinal; ICU, intensive care unit; PGY, postgraduate year; UTI, urinary tract infection.

Discussion

Bariatric surgery is a highly specialized field that requires significant training, usually through a fellowship. More basic bariatric procedures, such as SG, may be amenable to resident participation under the guidance of a well-trained surgeon. However, the literature has showed some concern that resident participation in bariatric procedures may worsen outcomes. In this study, we have demonstrated that perioperative outcomes after SG are comparable between residents, fellows, and surgeons.

It is expected that attending surgeons operate on patients with higher BMI, presence of hiatal hernia, and adhesions from previous surgeries, as they seem to be more challenging for residents. The results obtained support our hypothesis, that is, general surgery resident involvement in SG guided by an experienced bariatric surgeon does not lead to increased morbidity or short-term surgical outcomes.

In our general surgery program, the overall number of cases allotted to our residents depends upon their years of training. This happens due to a different schedule for each year, with PGY-2 and PGY-4 residents more exposed to the MIS rotation than residents from other classes. Our program has a well-established 1-year MIS fellowship where the fellow can perform a large number of cases. Moreover, our department is a high-volume referral center for bariatric surgery in an underserved area of the United States, and despite the presence of the fellow, residents are still exposed to a high number of bariatric procedures.

Patient safety at academic institutions has been an ongoing concern for the surgical community.¹³ Mostaedi et al. demonstrated that general surgery resident programs do not adequately expose residents to bariatric procedures.¹⁴ Residents may lack knowledge and experience to recognize early signs of complications and they may be unequipped to manage them. Therefore, resident involvement in bariatric surgery should be broadly investigated to better understand where programs can enhance surgical education to improve patient outcomes.

With the increasing number of bariatric procedures and the number of bariatric fellowships, the balance between surgical training and patient safety has become of utmost importance.¹⁵ By using data from a national database from 2010 to 2012, Aminian et al. found no significant increase in postoperative complication rates for laparoscopic SG conducted with fellow assistance.¹⁶ However, Goldberg et al., using the MBSAQIP database, identified increased complication rate when the procedure was performed with fellow or resident assistance.¹⁷ In this study, there was no statistical difference in complication rates between the groups.

Bonner et al., analyzing the MBSAQIP database, reported similar complication rates after bariatric procedures involving fellows, residents, and attending surgeons, with an increased OT for bariatric procedures performed with fellows when compared with residents or attending surgeons.¹⁸ Although this result may seem counter intuitive, it is worth noting that fellows have more autonomy during surgical procedures than residents. In addition, other studies have also showed increased morbidity with resident involvement in SG, such as UTI and cardiac events, increased readmissions, pulmonary emboli, and SSIs.¹⁹ In this study, there was no difference found between residents, fellows, and attending surgeons regarding 30 days outcomes.

Longer OT is associated with increased risk of SSI.^20,21 Studies have shown that resident or fellow involvement is associated with longer OT.^22–24 However, in this study, there was no difference in mean OT between the groups, and the SSI rate was low. Aly et al. compared residents and fellows performing different MIS procedures such as hiatal hernia repair, SG, RYGB, and others.²⁵ In their study, surgical outcomes were similar between fellow and chief resident assistance, and did not compromise patient safety.

Haskins et al., using the American College of Surgeons–National Surgical Quality Improvement Program (ACS-NSQIP) database, with >19,000 patients who underwent either RYGB or SG, showed that operations involving a senior-level resident were more likely to experience prolonged OT, cardiac and pulmonary events, wound and septic events, and longer LOS when compared with bariatric procedures involving no resident or junior residents.¹ The authors concluded that these outcomes were related to perioperative care rather than the intraoperative assistance by residents, suggesting that more focus and emphasis on perioperative progressive responsibility may be needed.

Limitations and strengths

This is a single-center and retrospective cohort study. It is important to note that we cannot estimate what steps of the surgery the residents performed. More experienced residents may have done the procedure almost entirely and junior residents might have done small tasks. Furthermore, we cannot determine the extent of resident involvement in robotic cases or postoperatively. However, this does not invalidate our results as our objective is to evaluate the safety and early outcomes of bariatric surgery with resident involvement in perioperative and postoperative care. In addition, selection bias may have existed as surgeons are more likely to operate in more complex cases, such as patients with higher BMI, concomitant hiatal hernia, or adhesions from previous surgeries.

Lastly, since complication rates after bariatric surgery are low and the number of patients in some groups was low, we may have not found a difference in outcomes because we had not enough events and power. The main strength of our study is to stratify the resident groups differently from what has been published in the literature. This allowed us to better understand some characteristics of our MIS service and how the residents are being exposed to bariatric procedures. Other programs may benefit from our data and exposing residents early in their surgery training to bariatric surgery.

Conclusion

Footnotes

Authors' Contributions

Study design was conducted by D.C., D.L.L., J.C., and E.M.-A. Data collection and analysis were carried out by D.L.L., R.D., and R.B. Article preparation and editing were done by D.L.L., R.D., X.P., R.B., J.C., E.M.-A., and D.C.

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

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