Comparison of economic and clinical outcomes between patients undergoing laparoscopic bariatric surgery with powered versus manual endoscopic surgical staplers

Abstract

Aims: To compare economic and clinical outcomes between patients undergoing laparoscopic Roux-en-Y gastric bypass (LRY) or laparoscopic sleeve gastrectomy (LSG) with use of powered vs manual endoscopic surgical staplers.

Materials and methods: Patients (aged ≥21 years) who underwent LRY or LSG during a hospital admission (January 1, 2012–September 30, 2015) were identified from the Premier Perspective Hospital Database. Use of powered vs manual staplers was identified from hospital administrative billing records. Multivariable analyses were used to compare the following outcomes between the powered and manual stapler groups, adjusting for patient and hospital characteristics and hospital-level clustering: hospital length of stay (LOS), total hospital costs, medical/surgical supply costs, room and board costs, operating room costs, operating room time, discharge status, bleeding/transfusion during the hospital admission, and 30, 60, and 90-day all-cause readmissions.

Results: The powered and manual stapler groups comprised 9,851 patients (mean age = 44.6 years; 79.3% female) and 21,558 patients (mean age = 45.0 years; 78.0% female), respectively. In the multivariable analyses, adjusted mean hospital LOS was 2.1 days for both the powered and manual stapler groups (p = .981). Adjusted mean total hospital costs ($12,415 vs $13,547, p = .003), adjusted mean supply costs ($4,629 vs $5,217, p = .011), and adjusted mean operating room costs ($4,126 vs $4,413, p = .009) were significantly lower in the powered vs manual stapler group. The adjusted rate of bleeding and/or transfusion during the hospital admission (2.46% vs 3.22%, p = .025) was significantly lower in the powered vs manual stapler group. The adjusted rates of 30, 60, and 90-day all-cause readmissions were similar between the groups (all p > .05). Sub-analysis by manufacturer showed similar results.

Limitations: This observational study cannot establish causal linkages.

Conclusions: In this analysis of patients who underwent LRY or LSG, the use of powered staplers was associated with better economic outcomes, and a lower rate of bleeding/transfusion vs manual staplers in the real-world setting.

Keywords:

• Laparoscopic roux-en-Y gastric bypass
• laparoscopic sleeve gastrectomy
• Bariatric surgery
• endoscopic surgical staplers
• costs

Introduction

According to the data from the National Health and Nutrition Examination Survey, 37.7% of adults in the US were obese (body mass index [BMI]: ≥30 kg/m²) and 7.7% had severe obesity (BMI: ≥40 kg/m²) in the 2013 to 2014 timeframe¹. The association between severe obesity and adverse health risks, including type 2 diabetes, dyslipidemia, hypertension, cardiovascular and cerebrovascular disease, and cancer, among others, has been well documented². In the US, the medical costs associated with obesity have been estimated at $209.7 billion annually in 2008 dollars, with the majority of the costs attributed to treating cardiovascular disease and type 2 diabetes^3–5.

Bariatric surgery is considered an effective procedure for stimulating significant weight loss and improving obesity-related comorbidities among severely obese persons^2,6,7. According to an analysis based on the Nationwide Inpatient Sample database, the number of bariatric surgeries performed in the US from 2008–2012 was estimated at 598,576⁸. Bariatric surgery techniques have evolved over the last decade, and nearly all surgeries are currently performed using the minimally invasive laparoscopic approach, which is associated with shorter hospital stays and lower complication rates than the open approach^8–10. Of the laparoscopic bariatric surgeries that are currently performed, the two most common are laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRY), which together accounted for 97.7% of bariatric procedures performed at academic medical centers in 2014¹¹. LSG is a relatively newer procedure than LRY, and its use has grown rapidly over the past several years, from less than one quarter of bariatric procedures at academic medical centers in the 4th quarter of 2011, to over 60% in the second quarter of 2014¹¹.

Endoscopic surgical stapling devices (henceforth, staplers) were introduced to facilitate tissue approximation and transection during endoscopic surgery¹². Staplers simplify the procedure and require less skill of the surgeon, but have been associated with complications, including leakage from staple lines, bleeding, and fistula formation^13–15. The first powered stapler (i.e. those for which the staples and the knife blade are driven not by manual force but instead by a power source) was approved for launch by the US FDA in 2010 for Covidien (now Medtronic, Minneapolis, MN) under the brand name “iDrive™ powered stapling system”¹⁶. Subsequently, Ethicon (Johnson & Johnson, Somerville, NJ) received approval to launch their ECHELON FLEX™ Powered ENDOPATH Stapler in the US in 2011¹². Both manufacturers have since introduced subsequent versions of their powered endoscopic stapling devices, namely the ‘iDrive™ Ultra powered stapling system’ from Covidien/Medtronic, and the ‘ECHELON FLEX™ Powered Plus Stapler’ with the ‘ECHELON FLEX™ GST System’ from Ethicon/Johnson & Johnson.

These powered staplers were developed to increase stability and enable more precise stapling relative to non-powered (manual) staplers. It is currently unclear, however, the extent to which such potential differences between the operation and performance of powered vs manual staplers translate into any differences in economic and clinical outcomes in the real-world setting. Thus, we conducted a large, retrospective, observational study in which we compared economic and clinical outcomes of US patients who underwent LRY or LSG with use of powered vs manual staplers.

Methods

Data and patient selection

This study’s data source was the Premier Perspective Hospital Database, which comprises administrative and hospital billing information for all hospital discharges occurring within more than 600 hospitals throughout the US. The database contains discharge-level information on all International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses and procedures recorded during each admission, a date-stamped log and cost of all billed items by cost-accounting department, administrative records on length of stay and discharge status, and selected information on patient, provider, hospital, and insurance characteristics. Although the database excludes federally funded hospitals (e.g. Veterans Affairs), the hospitals included therein are nationally representative based on bed size, geographic region, location (urban/rural), and teaching status.

Figure 1 shows the study’s patient selection process. Patients selected for study underwent elective LRY or LSG, as evidenced by ICD-9-CM procedure coding (See Supplemental Appendix 1 for a listing of all codes used in the study) during a hospital admission between January 1, 2012 and September 30, 2015. The first hospital admission for LRY or LSG during this period was defined as the index admission, and patients were required to be at least 21 years of age at the time of the index admission. Patients were also required to have an ICD-9-CM diagnosis code indicative of BMI ≥30 kg/m². Patients were excluded from the study if they had missing data on hospital supply, room and board, or total hospital costs, if they were transferred from another institution, or if they had other bariatric procedures during the index admission.

Figure 1. Selection of patient population. BMI: body mass index; LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy.

Use of either powered or manual staplers during the index admission was identified from hospital administrative records by searching for various combinations of device names (e.g. iDrive™ powered stapling system), model numbers (e.g. PCE45A), and/or descriptors of devices being “powered”. Staplers were also further classified by manufacturer (Medtronic powered, Medtronic manual; Ethicon powered; Ethicon manual) to support sensitivity analyses, as described below. Only patients for whom a stapler used during the index admission could be identified as either powered or manual were retained for study; patients with evidence of both powered and manual staplers were excluded from the study, due to the inability to assign them to one of the two study groups.

Measurement of patient and hospital/provider characteristics

Patient demographics and hospital/provider characteristics measured during the index admission included age, sex, marital status, race, payer type, urban vs rural hospital, hospital teaching status, hospital geographic region, hospital bed size, operating physician specialty, year of surgery/index admission, annual hospital surgical volume for LRY and LSG, and an indicator for whether hospital costs are derived from a cost-to-charge ratio vs procedural costing. Patient clinical characteristics measured during the index admission included BMI, the Charlson Comorbidity Index (CCI)¹⁷, the day on which the LRY or LSG surgery was performed after hospital admission, and several individual comorbidities (alcohol abuse, cancer, cerebrovascular disease, congestive heart failure, depression, diabetes, hypertension, hypothyroidism, liver disease, myocardial infarction, peripheral vascular disease, pulmonary circulation disorders, renal failure, rheumatoid arthritis, valvular disease). Comorbidities and the CCI were measured through the presence of ICD-9-CM codes, excluding those for which there was an indication that the comorbidity was not present on admission.

Measurement of economic and clinical outcomes

Economic and clinical outcomes evaluated during the index admission included hospital length of stay (LOS), total hospital costs, medical/surgical supply costs, room and board costs, operating room costs, operating room time (information on operating room time was available for most [93.6%] of the patients, and this outcome was analyzed only among patients with such information available), discharge to a home or home health organization vs other setting (e.g. skilled nursing facility), the composite complication of bleeding and/or transfusion based on ICD-9-CM codes and hospital billing records for transfusion supplies, and all-cause readmissions within 30, 60, and 90 days post-discharge. All costs were inflation adjusted to 2015 US dollars using the Medical Care component of the US Bureau of Labor Statistics Consumer Price Index. Within the study protocol, the bleeding and/or transfusion and all-cause readmission outcomes were designated as exploratory, while other outcomes were designated as primary. The exploratory outcomes were designated as such due to uncertainty regarding the validity of clinical coding (in the case of bleeding and/or transfusion) and because readmissions to the hospital within the Premier Perspective Hospital Database are captured only when the patient returns to the hospital in which the index admission took place, thereby introducing the potential for incomplete outcome data capture.

Statistical analyses

Statistical analyses were conducted for the overall population and were repeated separating the overall population into surgery type sub-groups (LRY or LSG). Bivariate analyses, stratified by the powered vs manual stapler groups, were utilized to describe patient and hospital/provider characteristics and unadjusted outcomes.

Multivariable regression models were used to compare outcomes between the powered vs manual stapler group, adjusting for all of the above-mentioned patient and hospital/provider characteristics. All models used link functions and error distributions which were tailored to the empirical distribution of the outcome variable based on the Modified Park test^18,19, specifically: log link and negative binomial or Poisson error distribution for length of stay; log link and gamma error distribution for costs; log link and Poisson error distribution for operating room time; and logit link and binomial error distribution for the remaining dichotomous outcomes (discharge to a home or home health organization vs other setting, the composite complication of bleeding and/or transfusion, and all-cause readmissions within 30, 60, and 90 days post-discharge). To account for the hospital-level clustered nature of the data, Generalized Estimating Equations (GEE) models were initially tested using an exchangeable working correlation structure—chosen based on a qualitative understanding of the potential nature of clustering within hospitals. For the model of room and board costs in the overall sample and all models of operating room time, an independent working correlation structure was substituted, because the models initially failed to converge. When neither an exchangeable nor independent working correlation structure resulted in model convergence, which was the case for all models of all-cause readmissions, Mixed Models were used in order to account for hospital-level clustering.

Adjusted outcomes were generated for each of the comparator groups using the least squares means approach based on observed margins. In the GEE models, inference was based on empirical (robust) standard error estimates. A two-sided critical value of 0.05 was used to determine statistical significance. All statistical analyses were performed using SAS version 9.3.

Sub-group and sensitivity analyses

Several sensitivity analyses were conducted to address potential issues of confounding or effect modification. First, in order to test whether the powered vs manual findings were driven by manufacturer-level phenomena, a sensitivity analysis was conducted in which the multivariable models were repeated comparing patients undergoing bariatric surgery with use of an Ethicon-manufactured powered stapler (which account for the majority of powered staplers) to those with use of a Medtronic-manufactured manual stapler. This analysis was also of interest, owing to the fact that these two categories of staplers formed the majority in the powered and manual platforms.

Next, the concomitant use of a buttress during the surgery was explored. According to the 2012 International Sleeve Gastrectomy Expert Panel Consensus Statement, the use of staple line reinforcement, such as a buttress or over-sewing the staple line, is thought to reduce bleeding along the staple line^20–23. However, staple line reinforcement has been shown to be associated with an increased risk of leaks in observational studies^21–23. Although the Premier Perspective Hospital Database does not contain information to support identification of over-sewing the staple line, buttress materials can be identified from hospital administrative records by searching for billing records of buttress materials. Thus, to address buttress as a potential confounding factor, a sensitivity analysis was conducted, using the overall population, in which unadjusted outcome data were compared between the sub-set of the powered and manual stapler groups, which had evidence of buttress, to examine whether these outcome data differed meaningfully from the primary analysis. A separate sensitivity analysis was conducted in which buttress was included as a covariate in the multivariable models—a variable which was not included in the primary analysis due to the likely low sensitivity of search algorithms to identify buttress materials (i.e. the absence of identified buttress materials does not necessarily indicate that it was not actually used).

Finally, circular staplers may be used to create the gastrojejunostomy anastomosis as an alternative to the staplers of interest under study, which introduces potential for use of another device in an important step of the LRY. There are presently mixed data on whether circular staplers increase the risk of complications in in LRY^24,25; however, if this technique correlates with use of powered vs manual staplers, it is possible that it could be a confounding factor for a number of the study outcomes—particularly costs arising from use of a second device. Thus, another sensitivity analysis was performed in which circular stapler use was included as a covariate in the multivariable models for the sub-group of patients undergoing LRY. This variable was not included in the primary analyses for the same reason noted for buttress above; bivariate analysis in the sub-group of LRY patients who had evidence of circular stapler use was not undertaken due to a small number of patients for whom there was such evidence.

Results

Patient and hospital/provider characteristics

Patient demographics, patient clinical characteristics, and hospital/provider characteristics are shown in in Tables 1–3, respectively. Of the overall study population (n = 31,409), 9,851 patients (mean age = 44.6 years; 79.3% female) were in the powered stapler group, and 21,558 patients (mean age = 45.0 years; 78.0% female) were in the manual stapler group. Among patients in the overall study population’s powered stapler group, 91.8% underwent bariatric surgery with use of an Ethicon-manufactured powered stapler, while 8.2% underwent bariatric surgery with use of a Medtronic-manufactured powered stapler. Among patients in the overall study population’s manual stapler group, 44.6% underwent bariatric surgery with use of an Ethicon-manufactured manual stapler, while 57.6% underwent bariatric surgery with use of a Medtronic-manufactured manual stapler; a small proportion of patients had evidence of both manufacturers’ brands of manual staplers being used. These proportions were relatively similar in the LRY and LSG sub-groups.

Table 1. Patient demographics.

	Overall study population				p	LRY sub-group				p	LSG sub-group				p
	Powered		Manual			Powered		Manual			Powered		Manual
	(n = 9,851)		(n = 21,558)			(n = 4,057)		(n = 9,613)			(n = 5,794)		(n = 11,945)
	n	%	n	%		n	%	n	%		n	%	n	%
Sex
Female	7,810	79.3	16,815	78.0	.01	3,286	81.0	7,465	77.7	<.001	4,524	78.1	9,350	78.3	.768
Male	2,041	20.7	4,743	22.0		771	19.0	2,148	22.3		1,270	21.9	2,595	21.7
Marital status
Married	4,986	50.6	10,537	48.9	.013	1,948	48.0	4,746	49.4	<.001	3,038	52.4	5,791	48.5	<.001
Single	3,619	36.7	8,075	37.5		1,501	37.0	3,740	38.9		2,118	36.6	4,335	36.3
Other	1,206	12.2	2,863	13.3		588	14.5	1,077	11.2		618	10.7	1,786	15.0
Missing	40	0.4	83	0.4	.013	20	0.5	50	0.5	<.001	20	0.3	33	0.3	<.001
Age in years, mean (SD)	44.6 (11.7)		45.0 (11.7)		.005	44.9 (11.7)		45.8 (11.8)		<.001	44.5 (11.8)		44.4 (11.7)		.594
Age category in years
21–24	292	3.0	630	2.9	.095	121	3.0	260	2.7	.003	171	3.0	370	3.1	.662
25–34	1,886	19.1	3,960	18.4		757	18.7	1,620	16.9		1,129	19.5	2,340	19.6
35–44	2,902	29.5	6,166	28.6		1,151	28.4	2,620	27.3		1,751	30.2	3,546	29.7
45–54	2,603	26.4	5,817	27.0		1,115	27.5	2,663	27.7		1,488	25.7	3,154	26.4
55–64	1,597	16.2	3,727	17.3		675	16.6	1,819	18.9		922	15.9	1,908	16.0
≥65	571	5.8	1,258	5.8		238	5.9	631	6.6		333	5.7	627	5.2
Race
White	6,723	68.2	13,123	60.9	<.001	2,869	70.7	5,718	59.5	<.001	3,854	66.5	7,405	62.0	<.001
African American	1,424	14.5	3,066	14.2		450	11.1	1,231	12.8		974	16.8	1,835	15.4
Other	1,704	17.3	5,369	24.9		738	18.2	2,664	27.7		966	16.7	2,705	22.6
Payer type
Commercial	5,773	58.6	13,162	61.1	<.001	2,161	53.3	5,234	54.4	<.001	3,612	62.3	7,928	66.4	<.001
Medicare	1,650	16.7	3,698	17.2		785	19.3	2,004	20.8		865	14.9	1,694	14.2
Medicaid	1,648	16.7	2,643	12.3		861	21.2	1,314	13.7		787	13.6	1,329	11.1
Other	780	7.9	2,055	9.5		250	6.2	1,061	11.0		530	9.1	994	8.3
Year of index admission
2012	985	10.0	5,481	25.4	<.001	515	12.7	3,213	33.4	<.001	470	8.1	2,268	19.0	<.001
2013	2,644	26.8	6,267	29.1		1,200	29.6	2,712	28.2		1,444	24.9	3,555	29.8
2014	3,365	34.2	5,828	27.0		1,342	33.1	2,201	22.9		2,023	34.9	3,627	30.4
2015	2,857	29.0	3,982	18.5		1,000	24.6	1,487	15.5		1,857	32.1	2,495	20.9

LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy; SD: standard deviation.

Table 2. Patient clinical characteristics.

	Overall study population				p	LRY sub-group				p	LSG sub-group				p
	Powered		Manual			Powered		Manual			Powered		Manual
	(n = 9,851)		(n = 21,558)			(n = 4,057)		(n = 9,613)			(n = 5,794)		(n = 11,945)
	n	%	n	%		n	%	n	%		n	%	n	%
Stapler manufacturer/group
Ethicon/powered	9,048	91.8	0	0	N/A	3,679	90.7	0	0	N/A	5,369	92.7	0	0	N/A
Medtronic/powered	803	8.2	0	0		378	9.3	0	0		425	7.3	0	0
Ethicon/manual	0	0	9,606	44.6		0	0	4,817	50.1		0	0	4,789	40.1
Medtronic/manual	0	0	12,418	57.6		0	0	5,145	53.5		0	0	7,273	60.9
BMI kg/m^2
30.0–34.9	134	1.4	332	1.5	<.001	45	1.1	135	1.4	<.001	89	1.5	197	1.7	.056
35.0–39.9	1,605	16.3	3,709	17.2		523	12.9	1,523	15.8		1,082	18.7	2,186	18.3
40.0–44.9	3,261	33.1	6,618	30.7		1,322	32.6	2,864	29.8		1,939	33.5	3,754	31.4
45.0–49.9	2,112	21.4	4,532	21.0		926	22.8	1,973	20.5		1,186	20.5	2,559	21.4
50.0–59.9	1,873	19.0	4,263	19.8		900	22.2	2,127	22.1		973	16.8	2,136	17.9
60.0–69.9	437	4.4	1,089	5.1		205	5.1	561	5.8		232	4.0	528	4.4
≥70	111	1.1	299	1.4		44	1.1	142	1.5		67	1.2	157	1.3
CCI score
0	4,293	43.6	9,019	41.8	.004	1,416	34.9	3,435	35.7	.114	2,877	49.7	5,584	46.7	<.001
1–2	4,607	46.8	10,365	48.1		2,121	52.3	5,035	52.4		2,486	42.9	5,330	44.6
3–4	851	8.6	1,885	8.7		466	11.5	988	10.3		385	6.6	897	7.5
≥5	100	1.0	289	1.3		54	1.3	155	1.6		46	0.8	134	1.1
Comorbidities
Alcohol abuse	24	0.2	64	0.3	.408	8	0.2	34	0.4	.131	16	0.3	30	0.3	.759
Cancer	644	6.5	1,216	5.6	.002	439	10.8	496	5.2	<.001	205	3.5	720	6.0	<.001
Cerebrovascular disease	8	0.1	53	0.3	.002	4	0.1	23	0.2	.091	4	0.1	30	0.3	.009
Congestive heart failure	194	2.0	517	2.4	.018	84	2.1	273	2.8	.01	110	1.9	244	2.0	.52
Depression	2,662	27.0	5,492	25.5	.004	1,242	30.6	2,657	27.6	<.001	1,420	24.5	2,835	23.7	.257
Diabetes	2,972	30.2	7,218	33.5	<.001	1,480	36.5	3,953	41.1	<.001	1,492	25.8	3,265	27.3	.026
Hypertension	5,633	57.2	12,966	60.1	<.001	2,441	60.2	6,167	64.2	<.001	3,192	55.1	6,799	56.9	.021
Hypothyroidism	1,354	13.7	2,970	13.8	.939	602	14.8	1,353	14.1	.244	752	13.0	1,617	13.5	.305
Liver disease	1,246	12.7	2,403	11.2	<.001	602	14.8	1,213	12.6	<.001	644	11.1	1,190	10.0	.018
Myocardial infarction	124	1.3	256	1.2	.592	63	1.6	116	1.2	.104	61	1.1	140	1.2	.482
PVD	66	0.7	181	0.8	.114	30	0.7	82	0.9	.501	36	0.6	99	0.8	.136
PCD	42	0.4	246	1.1	<.001	13	0.3	114	1.2	<.001	29	0.5	132	1.1	<.001
Renal failure	217	2.2	542	2.5	.096	82	2.0	265	2.8	.013	135	2.3	277	2.3	.964
Rheumatoid arthritis	200	2.0	460	2.1	.553	67	1.7	190	2.0	.201	133	2.3	270	2.3	.883
Valvular disease	96	1.0	265	1.2	.049	28	0.7	109	1.1	.017	68	1.2	156	1.3	.459
Day of surgery, mean (SD)^a	1 (0.2)		1 (0.9)		1.000	1 (0.3)		1 (1.3)		1.000	1 (0.2)		1 (0.2)		1.000
Circular stapler/buttress
Circular stapler	584	5.9	1,035	4.8	<.001	566	14.0	993	10.3	<.001	18	0.3	42	0.4	.66
Staple line buttress	2,259	22.9	3,195	14.8	<.001	448	11.0	1,283	13.4	<.001	1,811	31.3	1,912	16.0	<.001

BMI: body mass index; CCI: Charlson comorbidity index; LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy; PVD: peripheral vascular disease; PCD: pulmonary circulation disorder; SD: standard deviation.

^a Day on which bariatric surgery was performed; value of 1 indicates day of admission.

Table 3. Hospital/provider characteristics.

	Overall study population				p	LRY sub-group				p	LSG sub-group				p
	Powered		Manual			Powered		Manual			Powered		Manual
	(n = 9,851)		(n = 21,558)			(n = 4,057)		(n = 9,613)			(n = 5,794)		(n = 11,945)
	n	%	n	%		n	%	n	%		n	%	n	%
Urban/rural
Urban	9,202	93.4	18,794	87.2	<.001	3,711	91.5	8,185	85.1	<.001	5,491	94.8	10,609	88.8	<.001
Rural	649	6.6	2,764	12.8		346	8.5	1,428	14.9		303	5.2	1,336	11.2
Teaching status
Yes	6,130	62.2	11,229	52.1	<.001	2,479	61.1	4,902	51.0	<.001	3,651	63.0	6,327	53.0	<.001
No	3,721	37.8	10,329	47.9		1,578	38.9	4,711	49.0		2,143	37.0	5,618	47.0
Region
Midwest	1,523	15.5	2,850	13.2	<.001	778	19.2	1,668	17.4	<.001	745	12.9	1,182	9.9	<.001
Northeast	4,177	42.4	5,969	27.7		1,670	41.2	1,971	20.5		2,507	43.3	3,998	33.5
South	3,781	38.4	10,081	46.8		1,333	32.9	4,304	44.8		2,448	42.3	5,777	48.4
West	370	3.8	2,658	12.3		276	6.8	1,670	17.4		94	1.6	988	8.3
Bed size
1–300	3,224	32.7	6,244	29	<.001	1,226	30.2	2,718	28.3	<.001	1,998	34.5	3,526	29.5	<.001
301–500	3,329	33.8	8,276	38.4		1,500	37	4,150	43.2		1,829	31.6	4,126	34.5
>500	3,298	33.5	7,038	32.6		1,331	32.8	2,745	28.6		1,967	33.9	4,293	35.9
Operating physician specialty
Missing	84	0.9	751	3.5	<.001	29	0.7	414	4.3	<.001	55	0.9	337	2.8	<.001
General surgery	8,620	87.5	19,570	90.8		3,541	87.3	8,732	90.8		5,079	87.7	10,838	90.7
Abdominal surgery	174	1.8	800	3.7		55	1.4	349	3.6		119	2.1	451	3.8
Other specialty	186	1.9	194	0.9		142	3.5	58	0.6		44	0.8	136	1.1
Trauma surgery	75	0.8	215	1		12	0.3	44	0.5		63	1.1	171	1.4
Other	712	7.2	28	0.1		278	6.9	16	0.2		434	7.5	12	0.1
Costs from CCR method^a	1,471	14.9	6,451	29.9	<.001	552	13.6	3,006	31.3	<.001	919	15.9	3,445	28.8	<.001
Costs from procedural method	8,380	85.1	15,107	70.1		3,505	86.4	6,607	68.7		4,875	84.1	8,500	71.2
Surgical volume, mean (SD)^b	194 (101)		170 (95)		<.001	107 (58)		78 (52)		<.001	114 (54)		124 (71)		<.001

CCR: cost-to-charge ratio; LRY: laparoscopic Roux-en-Y gastric bypass; LSGL: laparoscopic sleeve gastrectomy; SD: standard deviation.

^a Hospital costs are derived from a cost-to-charge ratio.

^b Annual hospital surgical volume for LRY and LSG; in the LRY and LSG sub-groups, hospital surgical volumes are reported specifically in reference to the respective surgery type.

The majority of patients in the overall study population were between the ages of 35 and 54 years (powered = 55.9%; manual = 55.6%), white (powered = 68.2%; manual = 60.9%), and had commercial insurance coverage (powered = 58.6%; manual = 61.1%). Most were admitted for laparoscopic bariatric surgery at large (bed size = 300 to >500: powered = 67.3%; manual = 71.0%), teaching (powered = 62.2%; manual = 52.1%), urban hospitals (powered = 93.4%; manual = 87.2%). The hospitals to which the patients were admitted were primarily located in the South and Northeast regions of the US, reflecting the regional distribution of the hospitals contained in the Premier Perspective Hospital Database.

Of the overall study population, 54.5% of patients in the powered stapler group and 51.7% of patients in the manual stapler group had a BMI between 40.0–49.9 kg/m². Most patients had CCI scores of 2 and below (powered = 90.3%; manual = 89.9%). The most prevalent of the examined comorbidities were hypertension (powered = 57.2%; manual = 60.1%), diabetes (powered = 30.2%; manual = 33.5%), and depression (powered = 27.0%; manual = 25.5%).

Of the sub-group of patients who underwent LRY, 4,057 patients (mean age = 44.9 years; 81.0% female) were in the powered stapler group, and 9,613 patients (mean age = 45.8 years; 77.7% female) were in the manual stapler group. Of the sub-group of patients who underwent LSG, 5,794 patients (mean age = 44.5 years; 78.1% female) were in the powered stapler group, and 11,945 patients (mean age = 44.4 years; 78.3% female) were in the manual stapler group.

Unadjusted outcomes

Unadjusted outcomes are shown in Table 4. Statistical hypothesis testing was not performed for the unadjusted outcomes. Mean hospital LOS was 2.0 days for both the powered and manual stapler groups in the overall population (standard deviation = 1.5 for the powered stapler group and 1.8 for the manual stapler group). Among patients in the powered stapler group, mean total hospital costs, supply costs, and room and board costs were $11,478, $4,758, and $1,870, respectively; mean operating room time was 136.6 min, and operating room costs were $3,532. Among patients in the manual stapler group, mean total hospital costs, supply costs, and room and board costs were $13,388, $5,257, and $2,025, respectively; mean operating room time was 160.5 min, and operating room costs were $4,425.

Table 4. Unadjusted outcomes.^a

	Overall study population		LRY sub-group		LSG sub-group
	Powered	Manual	Powered	Manual	Powered	Manual
	(n = 9,851)	(n = 21,558)	(n = 4,057)	(n = 9,613)	(n = 5,794)	(n = 11,945)
Hospital LOS (days)
Mean (SD)	2.0 (1.5)	2.0 (1.8)	2.2 (1.9)	2.3 (2.4)	1.9 (1.2)	1.8 (1.2)
Median	2.0	2.0	2.0	2.0	2.0	2.0
Total hospital costs
Mean (SD)	$11,478 ($6,574)	$13,388 ($7,620)	$12,655 ($7,491)	$14,810 ($8,989)	$10,654 ($5,705)	$12,244 ($6,071)
Median	$10,405	$12,034	$11,646	$13,295	$9,853	$10,883
Supply costs
Mean (SD)	$4,758 ($4,280)	$5,257 ($4,023)	$5,338 ($3,270)	$5,828 ($4,309)	$4,352 ($4,822)	$4,797 ($3,714)
Median	$3,941	$4,479	$4,374	$5,069	$3,740	$4,011
Room and board costs
Mean (SD)	$1,870 ($1,847)	$2,025 ($2,732)	$1,993 ($2,384)	$2,262 ($3,228)	$1,784 ($1,342)	$1,834 ($2,237)
Median	$1,592	$1,597	$1,649	$1,769	$1,553	$1,421
Operating room costs
Mean (SD)	$3,532 ($1,900)	$4,425 ($2,550)	$3,953 ($2,137)	$4,938 ($2,892)	$3,237 ($1,653)	$4,012 ($2,149)
Median	$3,241	$3,894	$3,705	$4,321	$2,949	$3,513
Operating room time (minutes)
No of patients^b	9,136	20,268	3,704	8,923	5,432	11,345
Mean (SD)	136.6 (51.7)	160.5 (177.9)	159.8 (54.9)	192.6 (238.3)	120.9 (42.6)	135.2 (102.0)
Median	124.5	139.2	157.2	165.0	120.0	120.0
Discharge status, n (%)
Home or home health organization	9,807 (99.6)	21,258 (98.6)	4,028 (99.3)	9,455 (98.4)	5,779 (99.7)	11,803 (98.8)
Bleeding/transfusion, n (%)	236 (2.4)	776 (3.6)	147 (3.6)	442 (4.6)	89 (1.5)	334 (2.8)
Bleeding	194 (2.0)	448 (2.1)	126 (3.1)	261 (2.7)	68 (1.2)	187 (1.6)
Transfusion	153 (1.6)	572 (2.7)	93 (2.3)	322 (3.4)	60 (1.0)	250 (2.1)
All-cause readmission, n (%)
30-day readmission	435 (4.4)	1,008 (4.7)	243 (6.0)	583 (6.1)	192 (3.3)	425 (3.6)
60-day readmission	492 (5.0)	1,187 (5.5)	274 (6.8)	704 (7.3)	218 (3.8)	483 (4.0)
90-day readmission	544 (5.5)	1,303 (6.0)	308 (7.6)	768 (8.0)	236 (4.1)	535 (4.5)

LOS: length of stay; LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy; SD: standard deviation.

^a Costs are inflation-adjusted to 2015 US dollars using the Medical Care component of the US Bureau of Labor Statistics Consumer Price Index; statistical significance testing was not conducted for unadjusted outcomes.

^b Number of patients for whom operating room time data were available.

Most patients in the powered (99.6%) or manual (98.6%) stapler groups were discharged to home or a home health organization. Among patients in the powered stapler group, 2.4% had a diagnosis or hospital billing record indicative of bleeding or a transfusion during the index admission. Among patients in the manual stapler group, 3.6% had a diagnosis or hospital billing record indicative of bleeding or a transfusion during the index admission. In the powered stapler group, 2.0% had records indicative of bleeding, and 1.6% of patients had records indicative of transfusion (1.1% had both). In the manual stapler group, 2.1% had records indicative of bleeding and 2.7% of patients had records indicative of transfusion (1.1% had both). Thirty-, 60-, and 90-day all-cause readmission rates among patients in the powered stapler group were 4.4%, 5.0%, and 5.5%, respectively. Thirty-, 60-, and 90-day all-cause readmission rates among patients in the manual stapler group were 4.7%, 5.5%, and 6.0%, respectively.

Multivariable regression-adjusted outcomes

Multivariable regression-adjusted outcomes are shown in Table 5. Among patients in the overall study population, after adjusting for differences in patient and hospital/provider characteristics, adjusted mean hospital LOS was 2.05 days (p = .981) for both the powered and the manual stapler groups. Adjusted mean total hospital costs ($12,415 vs $13,547, p = .003) and supply costs ($4,629 vs $5,217, p = .011) were statistically significantly lower in the powered vs manual stapler group. Adjusted mean operating room time, on which information was available for 92.7% of the powered staple group and 94.0% of the manual stapler group, was numerically lower in the powered vs manual stapler group, but this difference did not reach the statistical significance level (135.0 vs 151.4 min, p = .066); however, adjusted mean operating room costs were statistically significantly lower in the powered vs manual stapler group ($4,126 vs $4,413, p = .009). The adjusted proportions of patients discharged to home or a home health organization were similar (99.93% vs 99.91%, p = .575) between the powered and manual stapler groups. The adjusted proportion of patients with bleeding and/or transfusion during the index admission was statistically significantly lower in the powered vs manual stapler group (2.46% vs 3.22%, p = .025). Adjusted 30-day (4.20% vs 4.08%, p = .749), 60-day (4.68% vs 4.86%, p = .679), and 90-day (5.27% vs 5.55%, p = .569) hospital readmission rates did not differ between the powered and manual stapler groups.

Table 5. Multivariable-adjusted outcomes.^a

	Adjusted outcome	Adjusted outcome	Difference	% Difference(Powered – Manual)	p
	Powered	Manual	(Powered - Manual)
Overall study population, n	9,851	21,558
Hospital LOS (days)	2.05	2.05	0.0	0%	.981
Total hospital costs	$12,415	$13,547	−$1,132	−8%	.003
Supply costs	$4,629	$5,217	−$587	−11%	.011
Room and board costs	$1,845	$1,946	−$102	−5%	.379
Operating room costs	$4,126	$4,413	−$288	−7%	.009
Operating room time (min)^b	135	151.4	−16.4	−11%	.066
Discharge status^c	99.93%	99.91%	0.02%	0%	.575
Bleeding/transfusion	2.46%	3.22%	−0.76%	−24%	.025
30-day readmission	4.20%	4.08%	0.12%	3%	.749
60-day readmission	4.68%	4.86%	−0.18%	−4%	.679
90-day readmission	5.27%	5.55%	−0.28%	−5%	.569
LRY sub-group, n	4,057	9,613
Hospital LOS (days)	2.31	2.26	0.05	2%	.635
Total hospital costs	$14,068	$14,644	−$576	−4%	.306
Supply costs	$5,555	$5,582	−$26	0%	.916
Room and board costs	$2,166	$2,240	−$74	−3%	.604
Operating room costs	$4,484	$4,959	−$475	−10%	.002
Operating room time (min)^b	162.7	179.1	−16.4	−9%	.273
Discharge status^c	99.82%	99.80%	0.02%	0%	.852
Bleeding/transfusion	3.70%	4.32%	−0.62%	−14%	.216
30-day readmission	6.16%	5.41%	0.75%	14%	.289
60-day readmission	6.62%	6.59%	0.03%	0%	.966
90-day readmission	7.62%	7.52%	0.10%	1%	.909
LSG sub-group, n	5,794	11,945
Hospital LOS (days)	1.87	1.88	0.0	0%	.987
Total hospital costs	$10,708	$12,124	−$1,416	−12%	<.001
Supply costs	$3,875	$4,736	−$861	−18%	.001
Room and board costs	$1,798	$1,936	−$137	−7%	.219
Operating room costs	$3,631	$3,871	−$240	−6%	.015
Operating room time (min)^b	121.6	130.5	−8.9	−7%	.092
Discharge status^c	100.00%	99.99%	0.01%	0%	.712
Bleeding/transfusion	1.34%	2.31%	−0.97%	−42%	.013
30-day readmission	2.97%	3.13%	−0.16%	−5%	.692
60-day readmission	3.44%	3.68%	−0.24%	−7%	.579
90-day readmission	3.71%	4.11%	−0.40%	−10%	.398

LOS: length of stay; LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy; SD: standard deviation.

^a Multivariable-adjusted outcomes were generated using the least squares means approach based on observed margins; costs are inflation-adjusted to 2015 US dollars using the Medical Care component of the US Bureau of Labor Statistics Consumer Price Index.

^b Number of patients for whom operating room time data were available: Overall, powered n = 9,136, manual n = 20,268; LRY, powered n = 3,704, manual n = 8,923; LSG, powered n = 5,432, manual n = 11,345.

^c Discharge to a home or home health organization vs other setting (e.g. skilled nursing facility).

Among patients who underwent LRY, after adjusting for differences in patient and hospital/provider characteristics, adjusted mean operating room costs were statistically significantly lower in the powered vs manual stapler group ($4,484 vs $4,959, p = .002). All other outcomes evaluated did not differ between the powered and manual stapler groups.

Among patients who underwent LSG, after adjusting for differences in patient and hospital/provider characteristics, adjusted mean hospital LOS did not differ between the powered and manual stapler groups (1.87 vs 1.88 days, p = .987). Adjusted mean total hospital costs ($10,708 vs $12,124, p < .001) and supply costs ($3,875 vs $4,736, p = .001) were statistically significantly lower in the powered vs manual stapler group. Adjusted mean operating room time was numerically lower in the powered vs manual stapler group, but did not reach the significance level (121.6 vs 130.5 min, p = .092); however, operating room costs were statistically significantly lower in the powered vs manual stapler group ($3,631 vs $3,871, p = .015). The proportions of patients discharged to home or home health organization were similar (100.00% vs 99.99%, p = .712) between the study groups. The proportion of patients with bleeding and/or transfusion was statistically significantly lower in the powered vs manual stapler group (1.34% vs 2.31%, p = .013). Thirty- (2.97% vs 3.13%, p = .692), 60- (3.44% vs 3.68%, p = .579), and 90-day (3.71% vs 4.11%, p = .398) hospital readmission did not differ between the powered and manual stapler groups.

Sensitivity analyses

Multivariable-regression adjusted outcomes for the sensitivity analyses comparing the Ethicon-manufactured power staplers to Medtronic-manufactured manual staplers are shown in Table 6. The results were largely consistent with the primary analyses, although the magnitude of the adjusted mean cost differences generally increased relative to the primary analyses. For example, in the primary analyses involving the overall study population, adjusted mean total hospital costs were $1,132 lower for the powered vs manual stapler group; this cost difference grew to be $1,777 lower for the Ethicon-manufactured powered vs Medtronic-manufactured manual stapler group. A few other differences were also evident, including: the loss of statistical significance on differences for operating room cost for all analyses; the loss of statistical significance on differences for bleeding/transfusion in the sub-group of patients undergoing LSG (to p = .0577); the introduction of statistical significance on differences for room and board costs for the overall study population and the sub-group of patients undergoing LSG; the introduction of statistical significance on differences for operating room time for the overall study population and the sub-group of patients undergoing LRY; and the introduction of statistical significance on differences for bleeding/transfusion and supply costs in the sub-group of patients undergoing LRY.

Table 6. Multivariable-adjusted outcomes for sensitivity analysis comparing Ethicon-manufactured powered staplers to Medtronic-manufactured manual staplers.^a

	Adjusted outcome	Adjusted outcome	Difference	% difference (Powered – Manual)	p
	Ethicon-manufactured Powered	Medtronic-manufactured Manual	(Powered - Manual)
Overall study population, n	9,048	12,418
Hospital LOS (days)	2.02	2.07	−0.05	−2%	.689
Total hospital costs	$12,261	$14,038	−$1,777	−13%	.022
Supply costs	$4,477	$5,902	−$1,425	−24%	<.001
Room and board costs	$1,783	$2,088	−$306	−15%	.020
Operating room costs	$3,951	$4,383	−$432	−10%	.193
Operating room time (min)^b	133	154	−21	−14%	.011
Discharge status^c	99.95%	99.95%	0.00%	0%	.963
Bleeding/transfusion	1.61%	3.05%	−1.44%	−47%	.013
30-day readmission	3.71%	4.06%	−0.35%	−9%	.428
60-day readmission	4.26%	4.85%	−0.59%	−12%	.260
90-day readmission	4.86%	5.50%	−0.64%	−12%	.282
LRY sub-group, n	3,679	5,145
Hospital LOS (days)	2.35	2.22	0.13	6%	.535
Total hospital costs	$14,340	$14,872	−$532	−4%	.741
Supply costs	$4,926	$6,142	−$1,216	−20%	.039
Room and board costs	$2,151	$2,301	−$151	−7%	.564
Operating room costs	$4,663	$4,966	−$303	−6%	.561
Operating room time (min)^b	160	181	−20	−11%	.046
Discharge status^c		Too little variability in outcomes to converge
Bleeding/transfusion	2.60%	4.51%	−1.91%	−42%	.039
30-day readmission	6.02%	5.84%	0.18%	3%	.846
60-day readmission	6.86%	6.99%	−0.13%	−2%	.906
90-day readmission	7.82%	8.18%	−0.36%	−4%	.774
LSG sub-group, n	5,369	7,273
Hospital LOS (days)	1.83	1.91	−0.08	−4%	.405
Total hospital costs	$10,420	$12,658	−$2,238	−18%	<.001
Supply costs	$3,759	$5,283	−$1,524	−29%	<.001
Room and board costs	$1,756	$1,961	−$205	−10%	.042
Operating room costs	$3,378	$3,819	−$442	−12%	.087
Operating room time (min)^b	121	132	−11	−8%	.069
Discharge status^c		Too little variability in outcomes to converge
Bleeding/transfusion	0.91%	1.44%	−0.52%	−36%	.058
30-day readmission	2.50%	2.86%	−0.36%	−13%	.385
60-day readmission	2.89%	3.43%	−0.54%	−16%	.264
90-day readmission	3.22%	3.73%	−0.51%	−14%	.336

LOS: length of stay; LRY: laparoscopic Roux-en-Y gastric bypass; LSG: laparoscopic sleeve gastrectomy; SD: standard deviation.

^a Multivariable-adjusted outcomes were generated using the least squares means approach based on observed margins; costs are inflation-adjusted to 2015 US dollars using the Medical Care component of the US Bureau of Labor Statistics Consumer Price Index.

^b Number of patients for whom operating room time data were available: Overall, Ethicon-manufactured powered n = 8,347, Medtronic-manufactured manual n = 12,081; LRY, Ethicon-manufactured powered n = 3,334, Medtronic-manufactured manual n = 4,954; LSG, Ethicon-manufactured powered n = 5,013, Medtronic-manufactured manual n = 7,127.

^c Discharge to a home or home health organization vs other setting (e.g. skilled nursing facility).

In the powered staple group, 22.9% (overall) and 14.0% (LRY sub-group) of patients had evidence of staple line buttress use and circular stapler use, respectively; in the manual stapler group, these proportions were 14.8% and 10.3%. The sensitivity analyses examining the potential role of staple line reinforcement through buttress in the overall study population and the use of circular staplers in the sub-group of patients who underwent LRY yielded results that were highly consistent with the primary analyses in terms of both magnitude and statistical significance. The detailed results of these sensitivity analyses are shown in Supplemental Appendices 2–4.

Discussion

To our knowledge, based on a review of the literature, the present study is the first to compare economic and clinical outcomes between patients undergoing laparoscopic bariatric surgery with powered vs manual staplers. We found that, among the overall population of patients who underwent either LRY or LSG, total hospital costs, supply costs, and operating room costs were lower for the powered stapler group vs the manual stapler group. Furthermore, we found that the rate of bleeding and/or transfusions during the index hospitalization was lower for the powered stapler group vs the manual stapler group. The relative incremental clinical and economic benefits of powered staplers were more prominent among patients who had undergone LSG than among patients who had undergone LRY; although they were generally directionally consistent across the two surgical sub-groups.

Owing to the unique nature of the present study’s findings, there are currently no studies to which the findings regarding the primary objective of comparing powered vs manual endocutters can be compared. However, other prior studies examining selected outcomes that were examined in the present study have reported relatively similar overall findings. For example, in three prior longitudinal cohort studies of patients undergoing bariatric surgeries (separately representing 19,651, 28,616, and 57,918 patients) including LRYGB, LSG, and other types of bariatric surgeries, the average hospital length of stay was reported to be 2.5 days²⁶, which is relatively similar to the 2.0 days reported in the present study. The half-day difference between the prior studies and the present study may be driven by the fact that there has been a secular trend of decreasing hospital lengths of stay over time²⁷ and that the present study’s time period spanned 2012–2015, whereas the aforementioned studies’ time periods spanned 2004–May 31, 2013, 2007–2010, and 2007–2009. The present study’s rate of bleeding (overall, 3.2%) is also similar to what was reported in a prior meta-analysis, which reported bleeding rates between 1.2–3.5%²². Furthermore, the present study’s readmission rate at 30 days (4.4%) is similar to that of prior studies (3.5–5%²⁶). Finally, in one prior single-center study examining patients undergoing LRYGB at the Stanford University Medical Center between May 2008 and November 2013, the mean operating room time ranged from 202–235 min, which is relatively similar to the present study’s mean operating room time of ∼183 min in the sub-group of patients undergoing LRYGB²⁸.

Despite the present lack of data that are directly comparable to those of the present study, the underlying hypothesis for why differences may be expected between powered and manual staplers is somewhat intuitive and may help to contextualize the present study’s findings.

Part of the benefit of the powered device (which in the present study was represented mostly by Ethicon staplers) may be derived from the combination of increased stability, along with superior control of tissue movement with advanced reloads that are available on these devices that potentially cause less damage to tissue, and help with formation of a more integrated staple-line. In benchtop testing on porcine stomach tissue, Ethicon’s powered staplers were found to reduce movement at the distal tip by 88% compared to manually-fired devices, thus potentially causing less trauma to adjacent tissue during thick transections²⁹. Specifically, surgeons (n = 19) fired each instrument/reload once (PSE60A/ECR60G, 030449/030459, and EGIAUSTND/EGIA60AMT); median reduction of distal tip motion was 88%, with a range of reduction of 71–95%²⁹. In pre-clinical analyses, fewer staple malformations were reported with the Ethicon’s powered stapling device compared to its non-powered version when fired on porcine small bowel specimens³⁰. Clinical studies in the US, Europe, and Asia have also demonstrated the utility of these device and reload combinations^31,32.

The other, more surgeon-related benefit may be derived from the speed and the procedural economy of effort which powered staplers allow in effectively executing 6–8 firings in a bariatric procedure. This may be offering the surgeon, who is required to make several decisions in each steps of the procedure, the psychological freedom to focus on the patient and to plan ahead for the next steps. Surgeons agree that improved endoscopic linear stapling device stability is a critical component of surgery and is likely to result in more frequent positive surgical outcomes³³. This could potentially reduce surgery stress based on the interesting theoretical framework of the biopsychosocial model (BPSM) of challenge and threat³⁴ that has been applied to explain differences in stress reaction to surgical device use³⁵. The framework is predicated upon the surgeon’s evaluation of the demands of a procedure compared against the possession or availability of necessary resources to cope effectively with such demands³⁴. When resources are perceived to be sufficient, a “challenge” state occurs, resulting in a surgeon experiencing more favorable cognitive, affective, physiological, and behavioral outcomes. In contrast, if a surgeon perceives that she/he does not possess the resources required to meet the demands of the situation, a “threat” state emerges. It has also been shown that poor surgical performance may arise when surgeons evaluate a stressful event as a “threat” instead of a “challenge”³⁶. Differences in bleeding complication/transfusion rates could potentially be driven by this combination of device- and surgeon-driven factors that favor the use of powered endoscopic staplers.

Although we were unable to precisely pinpoint the drivers of the lower total hospital costs in the powered stapler group, the largest cost sub-category differences between the powered and manual stapler groups were observed in supply costs and operating room costs. Future analyses should attempt to understand what changes in supply requirements drive the observed lower supply costs. We observed a directionally lower, although not reaching statistical significance, operating room time for the powered stapler group, which may in part explain the lower operating room costs for the powered stapler group.

Limitations

This study was subject to limitations. First, large administrative databases containing real-world healthcare data are, in general, currently limited with respect to detailed information on medical devices. Although the development and dissemination of Unique Device Identifiers (UDI) into such databases will substantially improve the ability to study medical devices in a real-world setting, the present-day reality is that devices used within the hospital setting must primarily be identified through search of non-standardized text fields which describe the device in an electronic medical record or hospital billing system. Such search strategies may theoretically have relatively high positive predictive value for the identification of target devices; however, they may lack sensitivity to identify all instances of the use of a given device or technology. Second, as is the case with any coded healthcare database, there is a potential for measurement error or misclassification arising from codes being recorded incorrectly or incorrect recording of a given device’s usage. Third, although we used multivariable regression models to control for multiple potential confounders, as well as hospital-level clustering, laparoscopic bariatric surgical procedures are complex, and their outcomes are driven by factors which we could not measure well, including but not limited to surgeon experience, surgeon technique when utilizing a stapler, patient tissue quality and thickness, and its interplay with staple height selection, prior surgeries, and the utilization of other devices that might facilitate the procedure (e.g. advanced energy dissectors); thus, our findings cannot be interpreted as causal. When considering the measured covariates, however, magnitudes of differences between the powered and manual stapler cohorts were generally small, despite some statistically significant differences driven by the large study sample sizes. Finally, the Premier Perspective Hospital Database is a non-probability sample which may not necessarily reflect the mix of institutional and surgeon experience of all hospitals in the US or populations residing in other countries.

Conclusions

In this large-scale analysis of patients who underwent LRY or LSG, the use of powered staplers was associated with better economic outcomes and a lower rate of bleeding complication/transfusion compared to manual staplers in the real-world setting.

Transparency

Declaration of funding

This study and development of this manuscript was supported by Johnson & Johnson (Ethicon, Somerville, NJ).

Declaration of financial/other interests

SR and EF are employees of Ethicon, a Johnson & Johnson company. AY, SY, IK, and SJ are employees of Johnson & Johnson. CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Acknowledgments

We would like to acknowledge Jay Lin and Melissa Lingohr-Smith from Novosys Health for editorial support and review of this manuscript.