Gastric Wall Thickness and the Choice of Linear Staples in Laparoscopic Sleeve Gastrectomy: Challenging Conventional Concepts

Elastomeric Polyesters in Cardiovascular Tissue Engineering and Organs-on-a-Chip

Cardiovascular tissue constructs provide unique design requirements due to their functional responses to substrate mechanical properties and cyclic stretching behavior of cardiac tissue that requires the use of durable elastic materials. Given the diversity of polyester synthesis approaches, an opportunity exists to develop a new class of biocompatible, elastic, and immunomodulatory cardiovascular polymers. Furthermore, elastomeric polyester materials have the capability to provide tailored biomechanical synergy with native tissue and hence reduce inflammatory response in vivo and better support tissue maturation in vitro. In this review, we highlight underlying chemistry and design strategies of polyester elastomers optimized for cardiac tissue scaffolds. The major advantages of these materials such as their tunable elasticity, desirable biodegradation, and potential for incorporation of bioactive compounds are further expanded. Unique fabrication methods using polyester materials such as micromolding, 3D stamping, electrospinning, laser ablation, and 3D printing are discussed. Moreover, applications of these biomaterials in cardiovascular organ-on-a-chip devices and patches are analyzed. Finally, we outline unaddressed challenges in the field that need further study to enable the impactful translation of soft polyesters to clinical applications.

Evaluation of automated staple sizes on gastric layer incorporation and intraluminal pressure for partial gastrectomy closure in an ex vivo canine model

OBJECTIVE

To evaluate the performance of automated staple sizes on a cadaveric canine partial gastrectomy model.

METHODS

Stomachs were transected through the gastric body axis and randomly allocated to two closure groups: Group B, thoracoabdominal (TA) stapler 3.5 mm staple cartridge (blue); Group G, TA stapler 4.8 mm staple cartridge (green). After construct completion, leak testing was performed for both groups and compared. Initial leakage pressure (ILP), maximal leakage pressure (MLP) and leakage location were recorded. Staple lines were evaluated by direct observation and fluoroscopy to assess sub-mucosal layer incorporation and staple conformation. Staple shape was classified as optimal or suboptimal. Significance was set at p less than 0.5.

RESULTS

Following gastrectomy, the mean double gastric wall thickness was 7.82 ± 2.05 mm at the gastric body. Mean ILP was significantly lower in groups G (17.13 ± 1.19 mmHg) compared to group B (50.46 ± 6.03 mmHg, p = 0.0013). Similarly, mean MLP was significantly lower in group G (21.41 ± 1.39 mmHg) compared to group B (64.61 ± 10.21 mmHg, p < 0.0001). Although group G had higher percentage of B-shaped staple formation compared to group B, this was not significant (group G; 92.38%, group B; 54.56%; p = 0.054).

CONCLUSION

The 3.5 mm TA staple cartridge (blue) achieved superior bursting pressures compared with the 4.8 mm TA staple cartridge (blue) for the closure of a canine partial gastrectomy model. Both staple sizes incorporated all gastric layers. No differences were noticed in optimal staple conformation between groups. In vivo investigation is warranted to evaluate the use of different staple sizes on gastric tissue perfusion, successful healing and post-operative stasis and dehiscence.

Laparoscopic vertical sleeve gastrectomy in felines: A cadaveric feasibility study and experimental case series in two cats

OBJECTIVE

To evaluate the feasibility of laparoscopic vertical sleeve gastrectomy (LVSG) in feline cadavers using endoscopic stapling equipment and report clinical outcomes in two live feline subjects.

STUDY DESIGN

Cadaveric study and experimental case series.

ANIMALS

Ten feline cadavers; two feline subjects.

METHODS

LVSG technique was refined on feline cadavers and included retraction of the liver, dissection of the stomach, assessment of proper location for gastrectomy via stapling, and leak testing. Appropriateness of gastrectomy, gastrectomy %, surgical times and complications were recorded. The procedure was performed on two live feline subjects, and they were followed for 4 months to report surgical complications.

RESULTS

LVSG was completed in 9/10 cadavers and both live patients. Stenosis at the incisura was recorded in 2/9 cadavers. No obvious leaks were seen in the 8 cadavers that were tested or either live patient. The mean surgical time for all cadaver procedures and live patients was 110.4 and 115 minutes, respectively. Mean weight of resected cadaver stomach was 10 g and the mean % of the total stomach weight resected was 27.6%. No intra- or postoperative surgical complications occurred in the live subjects.

CONCLUSION

LVSG technique appears feasible and safe for use in live patients.

CLINICAL RELEVANCE

This LVSG technique may be safely used for partial gastric resection in cats. Further studies are necessary to determine if it is effective at reversing the effects of obesity and diabetes in this population.

Measurement of gastric wall thickness after laparoscopic sleeve gastrectomy: obesity comorbidities and gastric wall in Chinese patients with obesity

Leakage of the sleeve remains constant after laparoscopic sleeve gastrectomy (LSG). This complication may be due to a mismatch between the staple height and gastric wall thickness (GWT). Our aim was to measure the GWT in Chinese patients with obesity and investigate the relationship between GWT and gender, body mass index (BMI), body weight, and obesity-related comorbidities. The GWT of 210 resected specimens after LSG was measured using a tissue measuring device, at a compression pressure of 8 g/mm² at three predetermined locations: antrum, midbody, and fundus. Two hundred ten patients (171 female/39 male). The gastric wall was thickest at the antrum followed by the midbody and thinnest at the fundus (3.02 mm, 2.22 mm, and 1.6 mm, respectively). Patients with gastritis and those with reflux esophagitis had thicker GWT at the antrum; male had thicker GWT at the antrum and fundus; patients with body weight > 100 kg, and those with BMI > 40 kg/m² had thicker GWT at the fundus. Linear regression analysis revealed a significant association between GWT with body weight and BMI at the antrum and fundus; Furthermore, hypertension associated with the GWT at the fundus (P < 0.01, P < 0.01, P < 0.02, P < 0.01; and P < 0.04, respectively). This study showed that the anatomical location of the gastric wall is a major predicting factor of GWT. Furthermore, gastritis, reflux esophagitis, male gender, BMI > 40 kg/m², body weight > 100 kg, and hypertension may increase the GWT at the antrum and fundus in Chinese patients with obesity.

Standardization of the One-anastomosis Gastric Bypass Procedure for Morbid Obesity: Technical Aspects and Early Outcomes

BACKGROUND

One-anastomosis gastric bypass (OAGB) has become an accepted metabolic/bariatric surgery procedure. This study aimed to describe our center's standardized OAGB operative technique and report early (≤30 d) safety outcomes in patients with severe obesity.

METHODS

The medical records of patients who had undergone either primary (n=681, 88.0%) or revisional OAGB (n=93, 12.0%) were retrospectively evaluated. Patient demographics, operative time, length of hospital stay, readmissions, reoperations, and ≤30-day morbidity and mortality rates were analyzed.

RESULTS

A total of 774 consecutive patients with severe obesity (647 female, 83.6%) underwent OAGB between January 2016 and December 2021. Their mean age was 36.2±10.8 years (range: 18 to 70 y) and mean body mass index was 42.7±4.2 kg/m 2 (range: 17.2 to 61 kg/m 2 ). Mean operating time was 52.6±19.9 minutes (range: 25 to 295 min) and length of hospital stay was 1.6±0.9 days (range: 1 to 9 d). Early postoperative complications occurred in 16 cases (2.1%), including 2 leaks with an intra-abdominal abscess (0.3%), bleeding (n=3, 0.4%), acute kidney failure (n=1, 0.15%), urinary tract infection (n=2, 0.3%), and intensive care unit stay (n=4, 0.5%). Seventy patients (9.1%) were readmitted, and re-laparoscopy was performed in 1 patient (0.1%). There was no mortality.

CONCLUSIONS

In the very early term, OAGB was a safe primary and revisional metabolic/bariatric surgery operation. Consistent performance of a standardized OAGB procedure contributed to low rates of morbidity and mortality in the hands of metabolic/bariatric surgeons with good laparoscopic skills at a high-volume center.

Optimization of Surgical Time Through the Implementation of a Rational Protocol to Prevent Bleeding in Sleeve Gastrectomy

Introduction: Staple line oversewing (SLO) is a prophylactic alternative due to its low cost and its effect of decreasing the incidence and severity of bleeding complications in sleeve gastrectomy (SG). However, this approach significantly increases the surgical time and may be associated with stenosis. The study aims to identify whether its usage was sufficient to optimize the surgical time in patients whose screening for the risk of occult bleeding was negative. Materials and Methods: The study enrolled 103 patients. Having the systolic blood pressure goal of 140 mmHg, the staple line is checked for bleeding points, counting as follows: >5 bleeding points proceed to SLO, <5 bleeding points are managed using clips, and if no bleeding points are found, the procedure can be completed. Results: The bleeding test was positive in 79.6% of the cases and oversewing was necessary for 44.7% of the total. The bleeding test result was significant for the increased surgical time. The mean surgical time in SLO was 16.4% higher than in clipping. There was a significant difference in surgical time between SLO and clipping; however, no significant difference was identified between clipping and continuing the procedure without further measures. No postoperative complication related to staple line bleeding was identified. Discussion: In a scenario with limitations for the use of high-cost homeostatic agents, the stratified protocol to prevent bleeding in SG stapling line was able to significantly reduce surgical time without significant added risks. Conclusion: A stratified protocol to prevent bleeding in SG stapling line was able to significantly reduce surgical time.

Influence of preoperative weight loss on gastric wall thickness-analysis of laparoscopic sleeve gastrectomy histological material

PURPOSE

The variables possibly enabling the prediction of gastric wall thickness during laparoscopic sleeve gastrectomy remain undetermined. The aim of the study was to identify preoperative factors affecting gastric wall thickness in patients undergoing laparoscopic sleeve gastrectomy.

METHODS

The measurements of the double-wall thickness of gastric specimen excised during sleeve gastrectomy were taken at three locations after 15 s of compression with an applied pressure of 8 g/mm². Statistical calculations were used to determine the influence of preoperative weight loss and other perioperative parameters on gastric wall thickness.

RESULTS

The study involved one hundred patients (78 female; 22 male). The thickest tissue was observed at the antrum with the mean value 2.55 mm (range 1.77-4.0 mm), followed by the midbody, mean 2.13 mm (range 1.34-3.20 mm), and the fundus, mean 1.69 mm (range 0.99-2.69 mm). Positive relationships were found between gastric wall thickness and both preoperative weight loss and age in all three measured locations; p < 0.05. In a linear regression model, age and preoperative weight loss were found to be statistically significant and positive predictors of higher gastric wall thickness only at the antrum. Male patients were observed to have thicker gastric wall at all three locations as compared to female patients.

CONCLUSION

Preoperative weight loss should be considered an important factor influencing gastric wall thickness. Age and gender can also be helpful in predicting the varying tissue thickness. Anatomical region is a key factor determining thickness of the stomach walls.

Battle of the buttress: 5-year propensity-matched analysis of staple-line reinforcement techniques from the MBSAQIP database

BACKGROUND

Vertical sleeve gastrectomy (VSG) has demonstrated to be safe; however, controversy remains on how to decrease major complications, particularly bleeding and leaks. There are variations in staple-line reinforcement techniques, including no reinforcement, oversewing, and buttressing. We sought to evaluate the effect of those methods on post-operative complications using the Metabolic and Bariatric Surgery Accreditation Quality Initiative Program (MBSAQIP) database.

METHODS

The MBSAQIP was queried for patients who underwent VSG during 2015-2019. A propensity-matched analysis was performed between different staple-line reinforcement (SLR) methods, specifically No reinforcement (NR), Oversewing (OS), and Buttressing (BR). The primary outcome of interest was complications within 30 days.

RESULTS

A total of 513,354 VSG cases were analyzed. The cohort was majority female (79.0%), with mean (SD) age of 44.2 ± 11.9 years and mean BMI of 45 ± 7.8 kg/m². Frequency of SLR methods used was 54%BR, 25.6%NR, 10.8% BR + OS, and 9.8%OS. There were no differences in rate of leaks among SLR methods. Compared to NR, BR was associated with decreased rate of reoperations, overall bleeding, and major bleeding (p < 0.05) but prolonged operative time and length of stay (LOS) (p < 0.05). OS was associated with decreased overall bleeding (p < 0.05) but prolonged operative times and length of stay (p < 0.05) compared to NR. Compared to BR, OS was associated with increased operative times, LOS, and rates of post-operative ventilator use, pneumonia, and venous thrombosis (p < 0.05). Patients with bleeding were associated with lower rate of BR (56% vs 61%) and higher rate of NR (34% vs 28%) compared to patients with no bleeding. Bleeding was associated with a greater frequency of leaks (4.4% vs 0.3%), along with higher morbidity and mortality (p < 0.05).

CONCLUSIONS

Of the reinforcement methods evaluated, BR and OS were both associated with decreased bleeding despite longer operative times. No method was found to significantly reduce incidence of leaks; however, bleeding was associated with increased incidence of leaks, morbidity, and mortality. The liberal use of SLR techniques is recommended for further optimization of patient outcomes after VSG.

Gastric Wall Thickness and Linear Staple Height in Sleeve Gastrectomy in Japanese Patients with Obesity

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a standard procedure due to its low complication rates and favorable outcomes. However, limited data are available regarding the optimal size of linear staplers in relation to gastric wall thickness (GWT).

METHODS

Between August 2016 and December 2020, we performed LSG in 70 patients with an average age, body weight, and body mass index of 42 years, 107 kg, and 40 kg/m², respectively. We measured the GWT at the antrum, body, and fundus using resected specimens. We used an endo-linear stapler, and the closed staple height (CSH) was 1.75 mm.

RESULTS

We found that the average GWT at the antrum was significantly thicker than the GWT at the body and fundus. There was a statistically significant relationship between body weight and the GWT at the antrum and body and obstructive sleep apnea and the GWT at the body. The average CSH/GWT ratios were 0.55, 0.62, and 0.90 at the antrum, body, and fundus, respectively. However, in 20 patients (29%), the CSH/GWT ratio at the fundus area was ≥ 1.0, and only preoperative body weight was a significant predictor for a CSH/GWT ratio of ≥ 1.0.

CONCLUSION

A light body weight may be related to a CSH/GWT ratio of ≥ 1.0 at the fundus.

Surprising neutral effect of shorter staple cartridges in laparoscopic sleeve gastrectomy

BACKGROUND

Consensus agreements regarding laparoscopic sleeve gastrectomy (LSG) advise against using staple loads less than 1.5 mm in closed staple height. However, few data exist to support this recommendation. We hypothesized that using staples with a shorter closed height would actually decrease incidence of intraoperative and postoperative bleeding during LSG, while not increasing the incidence of leak.

METHODS

All LSG cases for a single institution from 1/1/2014 to 12/31/2019 were exported for analysis. Two cohorts were established: 1. 'Green/Blue' group was cases in which no white cartridges were used and 2. 'White' group was cases in which any white cartridges were used. Demographic variables, procedural characteristics, hospital length of stay, and postoperative outcomes were compared between groups.

RESULTS

The study populations included 1710 patients, 974 in the green/blue group and 736 in the white cartridge group. There were no significant differences in postoperative leak, bleed, stricture, readmission, or death while using white staple loads as compared with the standard combination of blue and green loads.

CONCLUSION

Using staples with a shorter closed height during LSG did not impact the postoperative bleeding or leak rate. The impact from selection of shorter staples to achieve more tissue compression may be limited.

Primary Sleeve Gastrectomy and Leaks: The Impact of Fundus-Wall Thickness and Staple Heights on Leakage-An Observational Study of 500 Patients

Introduction: The most feared complication of laparoscopic sleeve gastrectomy (LSG) is staple-line leakage. Staple height and fundus-wall thickness might influence such leakage, and this study examined their possible impact on leak incidence. Factors including gender, age, comorbidities, and reinforcement of the staple line were also investigated.

Methods: A total of 500 patients between 17 and 71 years of age who were scheduled for LSG were selected to participate in the study. For technical reasons, 53 were excluded. The fundus-wall thickness of 447 patients after LSG was investigated. The impact of staple height, fundus-wall thickness, demographic and medical factors on leak incidence were investigated. Most of our patients (309) were female (69%), while 138 were male (31%).

Results: The mean thickness of the proximal fundus wall was 2,904 μm, 3,172 μm in men and 2,784 μm in women. The leak rate was 4.9%. Age, fundus-wall thickness, and BMI showed a strong influence on leak risk, but this effect was significant only for age (p = 0.01). Patient gender and staple size showed no significant influence on the correlation between fundus-wall thickness and leak risk. Gender displayed a small effect of influence on this correlation, with η2 = 0.05.

Discussion: Because older age had a significant effect on increasing the risk of staple-line leakage, there is a need for a more specific focus on these patients. Thinner fundus wall and female gender might predispose patients to staple-line leaks, but a significant value could not be reached. Therefore, staple size should remain the surgeon's choice based on clinical experience.

Endocutter Staple Height Auto-adjusts to Tissue Thickness

BACKGROUND

Surgeon choice of the appropriate staple height has been cited as a factor in the mechanical integrity of a staple line. However, tissue measured at the industry standard 8 g/mm² is usually thicker than the formed staple height of the staples that hold it together. This means that the pressure that the staples apply must be greater than 8g/mm². Additionally, formed staple heights in tissue may be different than formed staple heights of the same cartridge type when fired without tissue. This means that there is likely a compressive limit to the individual staples deployed by the stapling system. The purpose of this study is to establish the degree to which staple heights of endocutter staples auto-adjust to tissue and the compressive limit to tissue that this infers.

MATERIALS AND METHODS

Excised gastric remnants from laparoscopic sleeve gastrectomy were measured for tissue thickness at different external pressures. An optimized experimental staple line was then created in parallel to the clinical staple line. The doubly-stapled gastric sliver then underwent computed tomography with solid modeling software to measure staple heights.

RESULTS

Staple heights fired in gastric tissue were significantly different than industry labelled and control staple heights. Clinical staple heights were significantly shorter than measured tissue thickness at 8 g/mm². Staple height more closely approximated tissue thickness under 15 g/mm² of pressure, rather than the 8 g/mm² loading pressure used by industry for tissue thickness range labelling.

CONCLUSIONS

Staples deployed in human gastric tissue are taller than commercial labelling. The closed staple height corresponds to tissue thickness under 15g/mm² of pressure, not the labelled staple height. These results demonstrate that staple heights from modern endocutter staplers adjust to tissue, approximating a maximum compressive force just above 15g/mm².

Measurement of Stomach Wall Thickness to Guide Staple Selection during Sleeve Gastrectomy

BACKGROUND

Sleeve gastrectomy has been considered a primary bariatric surgery; however, surgeons concerned with staple line leakage often query whether staples selected during stomach resection are of an appropriate size. This study aimed to measure gastric wall thickness using pathology laboratory measurements and to identify variables correlated with stomach wall thickness in patients who had undergone laparoscopic sleeve gastrectomy.

METHODS

We obtained fresh resected stomach wall specimens from 30 patients. Stomach wall thickness was immediately measured postoperatively, comprising the muscle layer of the antrum, body, and fundus. Results were correlated with body mass index (BMI), age, and sex and with diagnoses of presurgical diabetes, hypertension, hyperlipidemia, and fatty liver.

RESULTS

Stomach wall thickness ranged from 3.4 ± 4.3 mm to 1.0 ± 9.6 mm at the antrum. Except for the whole layer at the body wall, there was no significant correlation between wall thickness and other factors. At the body wall, whole layer wall thickness was found to positively correlate with age, sex, diabetes, and smoking (r = 0.469, - 0.391, 0.396, and 0.349, respectively; p < 0.05 in all patients).

CONCLUSION

Stomach wall thickness varied among patients who had undergone laparoscopic sleeve gastrectomy according to samples taken at three stomach wall sites. The range in wall thickness was normal, and thus, surgeons need not hesitate in selecting the staple height. Also, our study may be helpful to guide surgeon choice concerning the third or fourth staple around the body area when considering a patient's independent factors.

Evaluation of staple line reinforcement after partial gastrectomy closure in an ex vivo canine model

OBJECTIVE

To determine the influence of stapling on leakage pressures after canine partial gastrectomy.

STUDY DESIGN

Ex vivo study.

SAMPLE POPULATION

Gastric specimens from 24 adult canine cadavers.

METHODS

Partial gastrectomy constructs were assigned to one of three closure techniques (n = 8 per group): group 1, stapled closure with a 90-mm thoracoabdominal stapling device and a 4.8-mm staple cartridge; group 2, hand-sewn double-layer inverting suture closure with 3-0 glycomer 631; and group 3, staple line reinforcement with an inverting Cushing suture pattern. Leakage and pressure testing were performed. Initial leakage pressure (ILP), maximal leakage pressure (MLP), and leakage location were recorded. Significance was set at P < .05.

RESULTS

Placement of a Cushing suture (group 3) increased ILP and MLP by 3.2-fold and 2.8-fold, respectively, compared with stapled closures alone (P < .001). Constructs closed with double-layer suture closure reached ILP and MLP 4.5-fold and threefold greater, respectively, compared with those with stapled closures alone (P < .001). Maximal leakage pressure did not differ between groups 2 and 3 (P = .14). Leakage occurred from the inverting suture line in all constructs of groups 2 and 3 and from staple holes in six of eight group 1 constructs.

CONCLUSION

Double-layer suture closure of canine partial gastrectomies achieved superior biomechanical properties compared with stapled closure techniques. Reinforcing staple closures with an inverting suture line improved resistance to leakage.

CLINICAL SIGNIFICANCE

Reinforcing single-layer closure of partial gastrectomies with an inverting Cushing pattern is recommended to improve resistance to leakage. In vivo investigation is warranted to evaluate influence of closure technique on gastric healing, postoperative stasis, ischemic injury, and postoperative dehiscence.

Increased staple loading pressures and reduced staple heights in laparoscopic sleeve gastrectomy reduce intraoperative bleeding

BACKGROUND

In laparoscopic sleeve gastrectomy, tissue thickness and closed staple height of the staple cartridge determine the pressure applied to the tissue. Prior studies have suggested 8 g/mm² to be ideal to minimize leaks or bleeding.

METHODS

We evaluated the relationship between staple loading pressure applied to gastric tissue and bleeding rate prospectively with a novel tissue measuring device and video-recorded operative findings for 116 patients undergoing laparoscopic sleeve gastrectomy performed by 2 surgeons at a single institution. Stapling protocol 1 was used for 64 cases, defined as standard practice, typically using green-blue-blue-blue Ethicon staple cartridges. Stapling protocol 2 was defined as blue-blue-white-white or gold-blue-white-white.

RESULTS

Tissue thickness measurements from 39 cases and staple load selection showed that surgeons preferred a median staple loading pressure of 15 g/mm². Tissue thickness measurements at 15 g/mm² had a mean of 1.86 mm at the antrum, 1.71 mm at the body, and 1.15 mm at the fundus, all significantly thinner than tissue thickness at 8 g/mm². For each 10 g/mm² increase in minimum pressure and maximum pressure value within each cartridge zone, there was a reduction in bleeding rate by 59.8% and 38.7%, respectively. Compared with stapling protocol 1, stapling protocol 2 had a lower intraoperative bleeding rate (90.2% vs 70.7%; P < .0001), usage of preventive hemostatic techniques (100% vs 10%; P < .0001), and hemostatic treatments (66% vs 46%; P = .04). In the 30-day postoperative period, there was 1 bleed in stapling protocol 1; there were no leaks.

CONCLUSION

Our data suggest using shorter closed staple heights to exert higher staple loading pressures decreases intraoperative bleeding rates in laparoscopic sleeve gastrectomy.

The influence of staple height on postoperative complication rates after laparoscopic gastric bypass surgery using linear staplers

BACKGROUND

The use of circular staplers with a low staple height is associated with a lower risk for complication when used to construct the gastroenterostomy in laparoscopic gastric bypass surgery. The influence of staple height on outcome when using linear staplers has not been studied.

OBJECTIVES

To investigate the influence of staple height when constructing the gastric pouch and gastroenterostomy using a linear stapler in laparoscopic gastric bypass surgery.

SETTING

Nationwide, Sweden.

METHODS

A retrospective, register-based cohort study, including all primary laparoscopic gastric bypass surgical procedures in Sweden registered in the Scandinavian Obesity Surgery Registry from January 2010 until January 2017, where linear staplers were used to construct the gastric pouch and the gastroenterostomy. Low stapler heights (closed height ≤1.0 mm) were compared with higher stapler heights (closed height ≥1.5 mm). The main outcome was postoperative complication within 30 days of surgery.

RESULTS

Within the study period, 27,975 patients were identified from the Scandinavian Obesity Surgery Registry. A closed staple height ≥1.5 mm was associated with higher risk for postoperative complication within 30 days of surgery compared with lower staple height. The risk was greater when used to construct the gastric pouch (adjusted odd ratio 1.30, 95% confidence interval 1.17-1.44, P < .001) as well as when constructing the gastroenterostomy (adjusted odd ratio 1.32, 95% confidence interval 1.20-1.45, P < .001).

CONCLUSION

The use of low staple height for construction of the gastric pouch and gastroenterostomy in laparoscopic gastric bypass surgery was associated with lower complication rates.

Factibilidade da gastrectomia vertical aberta no Sistema Único de Saúde

RESUMO Objetivo: analisar as características clínicas e epidemiológicas, as complicações pós-operatórias e a perda de peso em pacientes submetidos à gastrectomia vertical por via convencional, em uma instituição de saúde do Sistema Único de Saúde (SUS). Métodos: estudo transversal, longitudinal, retrospectivo realizado a partir da coleta de dados de prontuários para análise de variáveis em pacientes submetidos à gastrectomia vertical aberta, no SUS, no período de julho de 2013 a janeiro de 2017. Resultados: foram analisados 296 pacientes operados no período do estudo, dos quais 54% eram do sexo masculino; a média de idade foi de 39,9 anos ±11,4; o índice de massa corporal (IMC) médio no pré-operatório foi de 43,5kg/m² e no pós-operatório, de 30,3kg/m²; a perda de excesso de peso foi de 73,6%; 83,24% apresentaram uma perda de excesso de peso maior do que 50%; o IMC pré-operatório foi maior no grupo com perda de peso menor do que 50%. Observou-se uma taxa de complicações precoces com necessidade de internamento de 5,4% e um índice de mortalidade de 1%. Conclusão: a gastrectomia vertical aberta é uma técnica segura e eficaz para a perda de peso e que pode ser mais realizada no SUS. Dentre as variáveis avaliadas, o IMC prévio foi a única relacionada com o sucesso pós-operatório.

Complications after laparoscopic sleeve gastrectomy: can we approach a 0% rate using the largest staple height with reinforcement all along the staple line? Short-term results and technical considerations

BACKGROUND

Laparoscopic sleeve gastrectomy (SG) is gaining acceptance among bariatric surgeons as a viable option for treating morbidly obese patients. We describe the results of a single center's experience with SG, revealing a low complication rate.

OBJECTIVES

The aim of the study was to analyze the short-term results of laparoscopic SG using exclusively black staples with staple-line reinforcement.

SETTINGS

University hospital, tertiary referral center for bariatric surgery.

METHODS

SG was performed in 434 consecutive patients from December 2014 to March 2017. A technique is described where all operations were performed with attention to avoiding strictures at the incisura angularis and not stapling near the esophagus at the angle of His. All the interventions were performed using black cartridges and staple-line reinforcement using bioabsorbable Seamguard. A prospective chart review was conducted to determine the occurrence of early complications.

RESULTS

Follow-up data were collected for all patients at 90 days postoperatively. A total complication rate of 4.4% was observed. No leaks occurred in any of the patients. One case of bleeding occurred that necessitated a surgical exploration, which found the origin of the bleeding to be a diaphragmatic vessel. The 90-day mortality rate was 0%.

CONCLUSION

SG can be performed with a low complication rate. Selection of the appropriate staple height and reinforcement of the staple line could play a major role in optimizing the results of SG.

Initial Assessment of Mucosal Capture and Leak Pressure After Gastrointestinal Stapling in a Porcine Model

BACKGROUND

Anastomotic leak is a leading cause of morbidity and mortality in gastrointestinal surgery. The serosal aspect of staple lines is commonly observed for integrity, but the mucosal surface and state of mucosa after firing is less often inspected. We sought to assess the degree of mucosal capture when using stapling devices and determine whether incomplete capture influences staple line integrity.

METHODS

Porcine ileum was transected in vivo and staple lines were collected and rated for degree of mucosal capture on a 5-point scale from 1 (mucosa mainly captured on both sides) to 5 (majority of mucosa not captured). Mucosal capture was also assessed in ex vivo staple lines, and fluid leakage pressure and location of first leak was assessed. Stapling devices studied were Echelon Flex GST with 60-mm blue (GST60B) and green (GST60G) cartridges, and Medtronic EndoGIA Universal with Tri-Staple Technology™ with 60 mm medium (EGIA60AMT) reloads (purple).

RESULTS

GST60B and GST60G staple lines produced significantly better mucosal capture scores than the EGIA60AMT staple lines (p < 0.001, in all tests). Compared to EGIA60AMT, leak pressures were 39% higher for GST60B (p < 0.001) and 23% higher for GST60G (p = 0.022). Initial staple line leak site was associated with incomplete mucosal capture 78% of the time.

CONCLUSIONS

There are differences in degree of mucosal capture between commercial staplers, and the devices that produce better mucosal capture had significantly higher leak pressures. Further research is needed to determine the significance of these findings on staple line healing throughout the postoperative period.

Risk factors of perioperative morbimortality after laparoscopic sleeve gastrectomy: a club coelio multicenter study

OBJECTIVES

Postoperative complications after Laparoscopic sleeve gastrectomy (LSG) can dramatically compromise patient's outcome. The aim of this study is to analyze the per- and postoperative short-term outcomes after LSG and to assess predictive risk factors of complications.

METHODS

The study group consisted of 790 patients (610 women and 180 men) who underwent LSG In 2014. All interventions were performed by 18 experienced surgeons members of the Club Coelio. Data about preoperative work-up, surgical techniques, 30-days postoperative morbidity and mortality were collected. Endpoints were perioperative morbidity and mortality and assessment of potential risk factors for complications.

RESULTS

Mean age and body mass index were respectively 39 years and 41.5kg/m². Ninety-one patients (11.5%) had previous bariatric surgery. Morbidity rate was 4.7% (37/790) including 16 leaks (2.0%) and 9 bleedings (1.1%) and no deaths. Risk factors for leak were: previous adjustable banding (p = .0051), with no difference between removal of the banding and LSG in 1 or 2 steps, and type of endostapler (p = .0129).

CONCLUSIONS

Leakage after Sleeve was rare but still observed even in experienced hands. The leak rate is particularly high when LSG is performed after adjustable gastric banding removal.