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Standardised Sleeve Gastrectomy Without Reinforcement

Background and Objectives: Laparoscopic sleeve gastrectomy (LSG) has some unique complications, the most concerning of which is sleeve leak. Staple line reinforcement (SLR) has been suggested as a means of decreasing the risk of sleeve leak, but it increases the cost. However, there is little in the literature regarding the effect of standardized operative technique in reducing the complications and improving the outcomes in LSG. We sought to demonstrate that standardization of the operative procedure and perioperative care is the key to an excellent 30-day outcome and that SLR is not necessary to ensure a negligible staple line leak and bleeding rate. Methods: A prospectively maintained database was analyzed to identify 303 consecutive patients undergoing LSG between July 2010 and November 2017. Data on patient demographics, length of hospital stay, conversion to open surgery, perioperative complications, and mortality were analyzed. Standardized operative technique and postoperative protocol were followed in all cases. SLR was not used in any case. Results: Among 303 cases, there were 15 complications (5%), 5 (1.7%) of which were severe (Clavien-Dindo grade ≥3a). There were no conversions to open procedure, no staple line leaks, and no inpatient deaths in the cohort. No patient was readmitted with an early stricture. Conclusions: The use of a standardized operative and postoperative protocol led to an excellent early outcome in our LSG cases. Standardization may act to obviate the need for routine SLR techniques which are associated with a significant financial cost to both patient and hospital.


INTRODUCTION
The prevalence of obesity is continuing to increase worldwide, 1 and the effectiveness of bariatric surgery in treating these patients is widely accepted. 2 The improvement seen in diabetes control, blood pressure, and cardiovascular risk profile is also well documented. 3 Laparoscopic sleeve gastrectomy (LSG) has gained popularity as a stand-alone procedure because of its effectiveness and perceived ease of performing surgery. 4,5 LSG, although a safe procedure, has some unique complications, the most concerning of which is sleeve leak. Staple line reinforcement (SLR) has been suggested to be a method of decreasing the risk of sleeve leak and of staple line bleeding, 6 -8 although there is controversy about its effectiveness. 9 -11 Standardization of operative technique is another important determinant in optimizing outcomes and it is demonstrated to be effective in laparoscopic Roux-en-Y gastric bypass (LRYGB). 12 However, there are few publications in the literature regarding the effect of standardization in reducing the complications and improving the outcomes in LSG. 13 Our study, therefore, details our experience in performing LSG without SLR and using rigorous standardization of operative technique and postoperative protocol. We performed a retrospective case series analysis of 303 consecutive LSGs, using a prospectively collected database. LSGs were performed by a single surgeon who was beyond the learning curve. 14 We wanted to demonstrate that standardization of operative procedure and perioperative care is the key to excellent 30-day outcomes and that SLR is not necessary to ensure a negligible staple line leak and bleeding rate.
All procedures performed in studies involving human participants were in accordance with the ethics standards of the institutional and the National Research Committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. For this type of study, formal consent of patients is not required.

Operative Technique
LSG was performed with a 4-abdominal-trocar technique and Nathanson liver retractor. In 301 cases the greater omentum was dissected from the greater curve of stomach with a harmonic scalpel (Harmonic ACE; Johnson & Johnson, Wokingham, UK), whereas in 2 cases, a bipolar/ ultrasonic energy device was used (Thunderbeat; Olympus UK, Cardiff, Wales, UK) on a trial basis introduced by the hospital. The greater omentum was further treated with harmonic scalpel to produce a beaded appearance with the purpose of interrupting the epiploic arcade of vessels at multiple levels to reduce the risk of postoperative bleeding (Figure 1). A full fundus mobilization was performed until the left crus was identified.
An antrum-sparing sleeve commencing 2-4 cm from the pylorus was then created over a 30-French bougie, with sequential firings of a laparoscopic stapling device to form a sleeve with a capacity of 60 mL. The cartridge choice in all cases was standardized with an initial one 60-mm (4.4-mm staple height) black cartridge, followed by two 60 mm purple (4.0-mm staple height) (Medtronic Limited, Watford UK)/green (4.1-mm staple height) (Johnson & Johnson) cartridges (Figure 2). If the stomach was noted to be thick, a further 60-mm purple/green cartridge was used. LSG was then completed with 60-mm tan (3.0-mm staple height) (Medtronic Limited) or gold (3.8-mm staple height) (Johnson & Johnson) cartridges up to the gastroesophageal junction. To avoid angulation and potential stricture formation at the incisura, no angulation of stapling device was undertaken for the first 2 firings (Figure 3). This method ensured sufficient distance from the incisura. At the apex of the LSG, a distance of at least 1 cm from the gastroesophageal junction was ensured (Figure 4).
SLR was not used in any case in this series. A methylene blue test was used to assess any staple line leaks during surgery. Next, a hemostatic test was performed by artificially raising the patient's blood pressure to a supranormal level (Ͼ140 mmHg systolic). The isolated bleeding areas were then clipped with a laparoscopic clip applicator (Ligaclip 10 mm; Johnson & Johnson) to create a characteristic hedgehog appearance of the sleeve in situ ( Figure  5). A 20-or 24-French Robinson drain was placed alongside the staple line in all cases.
Enhanced-recovery principles were followed in all cases. All patients were encouraged to drink clear fluids with a straw from the recovery room and mobilized on the day of surgery, and a standardized medication plan was followed ( Table 1). Incentive breathing exercises were undertaken at the bedside. Patients were permitted free fluids via straw on the first postoperative day. Contrast studies were not obtained after surgery on a routine basis. Discharge was planned at postoperative day 2, if the criteria in Table  1 were fulfilled. All patients were followed up by the bariatric specialist nurse at 2 weeks after surgery and subsequently reviewed by the senior author.

RESULTS
A total of 303 LSGs were performed during the study period. The demographic characteristics are shown in Table 2. The mean age was 43.6 (SD 10.8) years, and body mass index was 47.8 (SD 7.41) kg/m 2 . Most patients were female (77.88%). The median American Society of Anesthesiologists grade was 2 (interquartile range [IQR] 2-3) and the median obesity surgery mortality risk score (OSMRS) was A (IQR A-B). The mean length of stay was 2.5 (SD 2.5) days. The 30-day or perioperative outcomes are shown in Table  3. Among 303 cases, there were 15 (5%) perioperative complications, of which 5 (1.7%) were defined as severe (Clavien-Dindo grade Ն3a). The rate of chest infection was 1.3%. Four patients were readmitted with dysphagia within 30 days. All investigations were normal, and no abnormality with regard to the sleeve was detected. There were no conversions to open procedure, no staple line leaks, and no inpatient deaths in the cohort. No patient was readmitted with an early stricture. Complications classified according to the Clavien-Dindo scale are shown in Table 4. One patient died within 30 days in a different institution.
Of 15 patients, 5 underwent reoperation, all procedures were performed laparoscopically. Two patients had a negative laparoscopy for abdominal pain. Two cases had a second laparoscopy with findings of intra-abdominal hematoma, but no active bleeding point was identified, therefore, the rate of bleeding in this series was 0.66%. In one case, a thermal injury to the sleeve from a bipolar ultrasonic energy device (Thunderbeat; Olympus UK) was identified.

DISCUSSION
In this study, we demonstrated that excellent results in terms of minimal complications and no sleeve leaks can be achieved, in our series of 303 consecutive LSGs. We believe that by applying a standardized operative technique and rigorous postoperative protocol, complications can be minimized.

Standardization of Technique
Attempts have been made to form a consensus as to a standard technique for LSG, 17 but there is still considerable variation between surgeons regarding elements of the operation, and a lack of data concerning standardization. Initial reports by Kueper et al 18 with their own standardized operative technique for LSG in a short case series (16 patients) demonstrated complication rates similar to those in their experience with laparoscopic adjustable gastric banding. Daes et al 19 reported that a standardized protocol resulted in a very low incidence of gastroesophageal reflux disease (1.5%) 6 -12 months after LSG, when focusing on technical details, including routine repair of hiatal hernia. A retrospective case series of 927 patients revealed that adopting a standardized operation to avoid excessive narrowing of the incisura in the final 489 cases resulted in no further episodes of gastric stenosis, compared with their initial experience. 20 Our own standardized technique has produced excellent outcomes in occurrence of early complications with an overall complication rate of 5%. Severe complications (Clavien-Dindo Ͼ3a) were seen in 1.7% of patients only.

Staple Line Reinforcement
The use of SLR is popular, with up to 80% of bariatric surgeons using it routinely 21 ; however, it remains an issue for debate. The potential benefit of lower leak and hemorrhage rates must be counterbalanced with the increased

Staple Line Leak
In our series, there were no staple line leaks and SLR was not used. Several meta-analyses have been performed to assess whether there is any difference in outcome with the use of SLR. The largest meta-analysis of patients was performed by Shikora and Mahoney 6 including 56,309 patients showed a benefit of SLR. Gagner and Buchwald 7 reported statistically   Our technique involved firing the first stapler at 2-4 cm from the pylorus. Commencing the firing at Ͻ2 cm from the pylorus can increase the leak rate. 31 The initial firing and the second firing of the stapler were always performed without angulation. The importance of avoiding narrowing of the incisura has been emphasized by Gibson et al. 31 Chang et al. 13 reported the positive effects of a technique change in stricture rates at the incisura. We believe that the rate of narrowing of the incisura is increased with angulation of the initial 2 firings of the stapler. In our series, the firings were always performed   without angulation and therefore may have prevented early strictures in all 303 cases. Also, s a 30-French tube was used in our series, and the propensity for narrowing the incisura with this tube size could have increased if the method of no angulation had not always been followed.

Hemorrhage
The hemorrhage rate in our series is 0.66%. We did not use SLR, but routinely performed a hemostatic test by raising the patients' blood pressure to supranormal levels. Metallic clips were used to control any areas of the staple line that bled after the hemostatic test, which creates a characteristic hedgehog appearance of the sleeve. We also treated the greater omentum with an ultrasonic device at multiple levels to create a beaded effect. We believe that the combination of these 3 factors acted to reduce the rate of bleeding seen in our series to levels equal to or lower than those in cases with SLR. Hemorrhage rates after LSG have been reported between 0.7%, 33 3.4%, 34 and 5.6%. 35 SLR seems to decrease the rate of both intraoperative and significant postoperative hemorrhage; Consten et al 36 reported an estimated decreased intraoperative blood loss of 90 mL with SeamGuard. Shikora and Mahoney 6 analyzed 41,864 patients and found a hemorrhage rate of 3.45% in patients without SLR compared to 1.23% with SLR. However, Simon et al 37 failed to show an advantage with SeamGuard. Saleh et al 38 reported 204 SLR cases with an overall complication rate of 6.9% and a risk of bleeding of 0.9%. This result is similar to our series, but we did not use SLR. Use of glue to reinforce the staple line has not been shown to reduce postoperative hemorrhage. 39 The use of tranexamic acid as a routine intraoperative method of reducing hemorrhage has been proposed. 40

CONCLUSION
The use of a standardized operative and postoperative protocols leads to excellent early outcomes in LSG. Standardization may act to obviate the need for routine SLR techniques,, which are associated with a significant financial cost to both patient and hospital.